Hi Juan, I’m a licensed engineer with an Australian airline. We’ve been carrying out fan blade re-lubes for a long time. It started in the 80’s on CF6 type engines on A300B4 aircraft in an attempt to alleviate odd N1 vibrations that intermittently plagued these engines. Very often, these inspections are carried out during overnight service where time to complete the job is an obvious factor. There is a lot of work to do. The blades can be removed in about 30 to 45 minutes. However, after removal they must be cleaned and inspected before re-lubing can be done. This is what takes all the time. It takes 10 minutes to wash each blade in denatured alcohol plus another 5 minutes to inspect. That’s 240 minutes plus 120 minutes. In addition, the fan disk must also be washed and inspected. When all is satisfactory, we re-lube the dovetails and the fan disk with two coats of spray molybdenum disulphide lubricant and wait for it to dry. It’s very easy to see how this simple procedure can quickly become a ‘rush job’ with the fan being reassembled almost as they’re waiting to tow the aircraft back on line. The tendency is to rush parts of the job: cleaning is not carried out properly making inspection more difficult. In short, it is easy to see how cracks that are potentially visible to the naked eye can be missed.
Thank you Juan for this clear and easily understandable summary of the extremely detailed and technical NTSB investigation report. I'm continually amazed at how much the NTSB can "reverse engineer" a disaster. When you said that they found that the blade failed at the 6 o'clock position, I was blown away. Anyway, thanks again for your no-nonsense reporting!
It wasn't that for me. It was the ability to envision its exit path. Lots of us who have worked with machinery have looked for witness marks from items that shouldn't meet but do. However when something has gone bang and let go in a fraction of a second and people can trace the component exit routes. That is way beyond my comprehension.
Chris Holt The NTSB did computer simulations using the actual design for the NG fan cowling, and found that the six o'clock impact caused forces that exceed the design criteria. A long-standing error that was only revealed by this accident, will require retrofitting of thousands of jet engines.
@@alleycatvietnam And I get frustrated when the NTSB comes up with a conclusion with no real evidence. Mostly, they do well. Also, many recommendations would cost tens or millions of dollars; in some cases, they'd render perfectly good airplanes no longer economical to fly. Aviation business runs on the edge of a razor, and often goes the wrong way.
It is why fly is so safe in this country, many of these type of investigations during the bloody years (plane designed and built from the 60s probably into the late 80s) had hundreds of minor engineering errors that were corrected. You look at the flight crash shows and many were before 2000 or planes built before 2000, many engineering and pilot corrections were done based on accidents and near accidents. The MAX accidents is an example of the type of things that happened a lot as they moved large aircraft designs developed during WW2 into passenger carriers, crashes with major airlines killing everyone were relatively common back then when compared to today and allowing people to bring or store bombs on the plane was one of those bugs.
Wow, what an amazing report Juan. This is one of your best ever. By the way if by chance you can't pass your medical, I'm damned sure that AIM would hire you as a curriculum advisor immediately. You are really good at this. What surprised me about this whole thing was that the stewardi, gave up their jump seats, the wing lost hydraulics, and the captain focused on keeping control. Aviate, Navigate, Communicate. All of these people are heroes! As a physics nut, and an aviation enthusiast and former controller, with a son in pilot training, thank you sir! I love these subjects, and you do a great job at it! Take care!
Another very informative video! Great job!. I am an AMT and have performed that blade lube on the CFM several times, although it has been years since the last lube I've been involved with. The process was done by removing all fan blades, laying them out on a large workbench, removing the old lube with alcohol, reapplying three coats of Dri-Moly lube from a spray can. Lube was applied to the dovetail of each blade, the spacer, and retainer. The blades then are reinstalled back into the engine in the same order as removed. An engine run is performed to check vibration before the next flight. This work was done on a routine "B" check overnight, one engine at a time. A visual inspection was accomplished but no NDT was involved.
blancolirio Juan as a 30 yr AMT @ UAL I would like to add to Mr. Behring”s statement that at UNITED ultrasound inspections are performed on each fan blade in addition to a DETAILED VISUAL INSPECTION of the fan hub assembly. Keep up the good work gents.....
Just read entire com, CVR. She did an amazing job not fully realizing what was wrong until on the ground. Thank God she (and FO) had the experience to make good decisions, despite scrapping checklists. To much going on. We all learn it early on -- Fly the Airplane, Fly the Airplane, Fly the Airplane. If necessary, fly it all the way through the crash sequence.
Lubricant is very thick grey lubricant of graphite grease so once they are removed they have to be stored in a specific sequence so that once they are reinstalled and run they will meet the vibration limits. This paste prior to inspecting the blades have to be thoroughly cleaned, then inspected then lubed again and installed lots of work.
Another "home run" Mr Juan!! You keep knocking them out of the park one after another!! Always learning tons of cool aviation stuff from your great videos!! Muchas gracias!!
Juan, your best one yet. Kudos to this fine crew again, the flaps 5 call and speed was a great call on their part. Max brakes will stop a 700 at 180 knots in Philly no problem. Professionals in the cockpit, and Juan to communicate clearly just why that matters. Great video!
Love it Juan. Great information. As the former ALPA Air Safety Chairman for my airline, you should wind up at the NTSB or start your own consulting company. I know John Cox from USAirways did this.
Juan, I'm not a pilot nor am I involved in air travel. I just wanted to say your presentation is so spot-on that I enjoy listing to you. You are a treasure! YT should feature you and your presentations as an example of how to correctly deliver content.
Heartfelt video, especially near the end -- our condolences to Jennifer Riordan's family. Kudos to the crew for doing all they could to land safely. Thx for the detailed explanation, Juan. Take good care!
She was the right captain to have on that flight at that time. Her experience as a Naval fighter pilot was a great asset to have in this situation. If you go to the Flight Channel and search for SWA 1380 you will see a flight simulation of what happened and hear the radio transmission. Condolences to the family of the passenger that died.
The level of detail in your videos continues to impress me. Also I keep learning how amazing the flight crew is on your average airliner. And, the unsung heroes are the cabin crew. Excellent video!
@@jimallen3392 But there’s nothing wrong with giving kudos for a job well done, in any field. Frankly, the flying public could stand to do a better job, by actually paying attention to the safety briefings, following crew instructions, not being disruptive, etc. (in general, I mean; seems like the folks on this flight did fairly well).
If you ever decide to hang up the wings, I'll bet the NTSB would love to get someone such as you on staff Juan. A 'hobby' becomes work type of thing. Hmmm Excellent, fact filled report here. Thanks 👍👍
I agree Juan has the respect of the aviation industry and a growing public image, exactly the type of person needed to convey in terms understood by 'laymen' the findings or otherwise of the NTSB.
He should have 1M subs within 2 years. At that point, he'll be viewed more than the NTSB at their preas releases. It would do the NTSB good to have them as their PR guy. It would do news oulets good to have them as a talking head when anything aviation related goes down, but youtube is still a big threat to most MSM.
I will chime in here. too. Juan does his research, AND speaks in pilot terms of course...so maybe as a pilot I might be biased because I know what he's saying? BUT? I think the layperson can understand what Juan says and explains.
Excellent report Juan. You have a great talent for analyzing these events and relaying the facts to those of us who know nothing about the mechanics of jet engines, but are willing to listen.
Thank you for the link to the transcript. Quite a moment when the Captain mutters, ''Heavenly Father.' The crew deserves praise for a job very well done!
Juan, All that I find surprising is that you do not have more followers. Another report hit out of the park, clear, concise and in a way that the less technical of us can easily follow. Thank you, for all of your reports, on so many subjects!
I have zero aviation experience yet I find your explanations so easy to understand. I pray that every commercial pilot I fly with has the depth of caring and knowledge that you have Juan! You are doing a fantastic job and I think you should be considered for a NTSB chairperson!
efox2001 I recently learned the term “moose stalls”. Apparently the term was coined in Alaska because of stall-spin crashes by pilots doing turns around moose while either observing or hunting them and the plane gets too slow for the bank angle (a higher speed stall) and they are unable to recover because of the low above ground altitude.
Great breakdown and explanation. I think it would be difficult for a flight attendant to tell pax to vacate the jump seat and sit on the floor so crew can be seated. Maybe they could find a way to add a 4th belt to certain rows and squeeze some skinny people together for emergencies. BTW, the flight # is transposed in the title.
ShooterReady...I can hear it now....flight attendants are sued for discrimination because they judged some passengers to be fatter than other passengers..OH MY..!! Don't tell CNN, they will pounce on this and run with it for 6 months..!!
That conflict (a flight attendant having to tell a passenger that the FA is more important than the passenger) was noted, at least during the hearing. However, it should also be noted that in this incident, _nobody_ was seated in the forward jumpseats during landing. There was room for two of the flight attendants to sit there, and the third could've pushed the deadheading employee out of one of the aft jumpseats. I'm not judging... there must've been a lot of chaos in the cabin, and the landing occurred much sooner than expected (after the flight crew was advised of the passenger's condition). But I think the NTSB is right to suggest that FAs be reminded that it's crucial that they be seated and strapped in during landings, especially emergency landings.
@@DougPardee This situation reminds me of the protocol if the oxygen masks have to be used and their is a child sitting next to it's mother or an adult. The protocol is for the mother/adult to put their oxygen mask on first and then putting the child's mask on them. The reason, I think, is that if the adult were to try and get the child's oxygen mask on first, there could be the chance that the adult could pas out before being able to get it on the child and both could suffer oxygen deprivation, or worse, as a result.
I know that technically the flight attendants should have been in their jump seats, but really, can you imagine kicking out traumatized passengers so they can sit in safety? Sometimes you need to make judgement calls appropriate to the situation.
Thanks Juan, we’ve all heard the ATC communication aboard this flight and saw the aftermath of the destruction. Today I have a much better understanding of the horror in the cockpit. The crew did a great job, considering the totality of the failures and the lack of time to comprehend them. 👍🏻👍🏻
The outer pane is taking all the pressure. Its the main structural element. The middle pane has the hole in it. Its just a backup. Either pane can take the pressure. The inner pane keeps the passenger rash off the middle and outer. The inner pane has no hole. I have assembled quite a few.
A reminder for anyone traveling on a plane. If you see the inner pane coming out from the sidewall. Please do not be alarmed. The inner pane is just trim and a very thin plastic window. Its there to keep passengers from scratching the real window. Nothing structural. Kindly let a flight attendant know after the flight is over and line maintenance can address the the issue.
As always, thank you for your clear, concise, no nonsense explanations. We appreciate the effort you obviously put into these reports and the respect for the victims. We’re praying for your return to excellent health!
The passenger cabin windows are one piece They are larger than the window opening the widow is held in position with clips and the cabin pressure keeps them sealed against the inner skin. the panel on the inside is approximately 1/16 inch thick and is part of the cabin interior decorative side wall. the entire interior side wall panel is easily removed . The function of the inner panel is to keep passengers from scratching the inside of the pressure window with sharp objects and diamond rings because scratches will create stress riser, which could cause the window to fail. the other purpose is provide a cavity between the inner and outer windows for cabin air to keep the outer window defrosted. the small hole is to allow that cabin air to bleed back into the cabin.
Again just an excellent explanation of a very involved issue. You just amaze me with your ability to explain very technical issues in a manner most every one can understand. Keep up the good work. Thanks
Thank you, Juan. Your experience, knowledge, and dedication in all the work you put into this channel are a great service to aviation. You dig in and explain so that we may try to follow and understand. With deep appreciation from a pilot with a shortened career, who follows your schedules and inquiries, /romain (Continental Airline, 1966-1981, Captain and Check Airman, 1977-1981; Sr. Pilot, USAF, SD and Cal.ANG, 1957-1971)
As a product designer, I'm stunned at the image of people with the mask only over their mouth and not their nose. Note to the designers of these systems: All you have to do is add a small nose-shaped indentation in the rim of the cup and that will automatically tell people to cover their nose. Yes, you'll have to redesign the mould. Yes, the mould will be slightly more expensive. Yes, people WILL use the oxygen mask correctly as a result.
Great explanation of the NTSB findings Juan. The crew did a great job given the multiple problems that they were faced with they got the plane down quickly and choosing a fast landing rather than extending unknown stuff into the wind on an aircraft that was displaying wonky handling was a good call given the long runway. Anyway, thanks Juan for the as always detailed briefing from a pilot's point of view, way more informative than a reporter with no airline knowledge.
Thank you Juan for your passion and tribute to Jennifer, who lost her life. It's easy to "just do your job". I know my friends and relatives who pilot are like you. Airline pilots are still a breed apart for the most part and I am thankful every time I fly.
Thanks for the in-depth explanation of this event. It was a lot more complicated than I had realized. My compliments and admiration to the flight crew, in their handling of the situation. Makes me, worried about future flights with the pilot shortages and the low time aircrew coming on line. I am afraid that not only inexperienced, but they don't fully understand what they are doing.
Very well done Juan... and it's good to be reminded of the professionalism of all our pilots, especially USN & USAF (I'm watching this on a challenging day -12/6/19)
As usual, you add to my list of skills to help keep myself calm during an emergency and trust the flight professionals, fore and aft, to do whatever can be done to get us all on the ground safely. You are still contributing a lot to the industry, even during your furlow. Thanks.
Congrats on such a fabulous upday Juan...so much information presented so a layman can understand. Thanks for that. So sad this woman lost her life...RIP
Thanks Juan for the great explanation and expert insights into a complex and difficult accident. I appreciate the way you make this information accessible to those of us who aren’t professional airline aviators.
This is my fist time to comment a video ever. Great job on presenting facts, lessons learned, combined with respect to the the victim of this incident. Hat off for you
Brilliant explanation, so well explained. Juan, if you ever get the time to write, a book from you would be a 'must have'. There would be a lesson in it for everyone.
I'm beginning to see a pattern in complex aircraft emergencies. Emergency checklists are practically useless. Emergencies are chaotic, and can't be rehearsed. Aviate, navigate, communicate. Also, delegate! One pilot should fly the plane, the other should handle the rest.
Emergency checklists and training assume a textbook scenario. They are useful in that they give very good guidance in situations that, if incorrectly handled, can become very chaotic indeed. EXPERIENCE, however, is the factor that determines weather the checklist/recurrent training guidance is applicable in non-textbook scenarios such as this one. The vast majority of non-normals are simple, textbook scenarios that work very well with checklists. Very little experience required. These non-normals happen every day and don't make the news as they are non-events. Multiple unrelated failures rely on the experience of the pilots to do the right thing given the scenario. We are very lucky in North America that we still have very experienced pilots flying our airplanes. In the case of SW 1380, an inexperienced crew may have been the catalyst to a very large disaster indeed. YOU GET WHAT YOU PAY FOR!
You are clearly wrong. It is directly because of emergency checklists practiced over and over again that directly resulted in the pilot correctly managing and responding automatically and correctly to multiple emergencies without having to refer to the checklist. But because she practiced these emergencies and checklists many times she knew exactly how to react and what to do without referring to a checklist and utilizing parts of checklists automatically that helped her emergency, saved the plane, passengers and crew directly because checklists exist and were practiced. Agsin your dead worng, check lists are critical
@@n6mz Very well said. DIA installed a very expensive automated baggage handling system that never worked. Robots are good for redundant tasks, but are complete failures with the unexpected. All tjhey do is shut down. The MCAS system is a good example.
@@n6mz I do think about this. A computer would be able go through a checklist almost instantly (and continously) and never forget anything or do it in the wrong order.
Thank you for another amazing report. Main stream media just can’t dedicate such time to an amazing report. Nor would they find it news worthy. But you do and that’s why we appreciate the time you put into sharing and educating all of us....
Juan, thanks for taking a complex topic of great importance and explaining it in clear, understandable terms. The graphics also help to see where the parts are located and to see the damage after knowing where everything fits together. Great job as always. Thanks!! - Dean from Minnesota
The amount of research, testing and resulting complexity of airliners never cease to amaze. It's sad that these masterpieces of engineering are often taken for granted. I'm really impressed by your to-the-point delivery and content quality. Even if your clips were 1 hour long, they'd seem too short.
In addition to Air Force and Navy pilots, I have worked with Marines who fly and manage a crew exceptionally well. I’ve also worked with civilian pilots who are easily at the same level. The learning never stops. It is the personality that determines the result, not the source of the initial training.
Nice creative writing, but fan blades don't oscillate. Need to come up with something better. Maybe "when the fan blades break and puncture the defication holding tanks, you want a Naval carrier pilot controling the yoke."
@@pawswet9476 Marine pilots are trained by the Navy. Navy and Marine pilots are basically the same just different uniforms and missions. The vast majority of the ones I have worked with in my 42+ years in aviation are top notch and would fly with them anytime, anywhere, under any circumstances.
I was a ship's company officer on a carrier during Vietnam. Watching the planes land on a moving, bobbing, very short deck that is at an angle to the direction of travel, at night .... adds another level of skill, required concentration … I always thought other pilots should at least get a cockpit ride onto a carrier just for the experience. Juan??
I learned so much from your report. Thank you for the context you provided and carefully described for each of the multiple and simultaneous emergencies. I can only react with enormous respect for the crew, the engineers and crafts persons who design and manufacture the parts, and having your level head, practical experience and voice that broadens our view and understanding.
The clanking sound while the blades are windmilling is coming from a midspan shroud. Theres a little raised protrusion in the middle of the blade. This keeps the blades in relative position and lowers stress on the root. The blades actually sling outwards in the hub. The blade arrangement expands ever so slightly once at speed. The lube helps the blades seat in the dovetail. This arrangement also has a abradeable material near the tips on the case. The case is there hold this material. This material is cut by the blades at initial runup of the engine. It provides a positive seal between the tip of the blade and the case. It makes it so you dont have air pressure leaking past the outside of the blade. Just like a winglet tries to limit the vortex. This material completely eliminates the vortex. Makes the engine more efficient and highers the compression ratio.
Great job, Juan. I usually get my info from reading these reports, but I very much enjoy your take on them. One correction based on your comment at 5:09: The 737-100 and 200 were powered by P&W JT8D turboFAN engines, albeit low bypass by today's standards. The JT8D was based on the military JT8, military designation J52 -- an actual turboJET that powered the A-4D and later series as well as the A-6 series and the Hound Dog missile. A fan was added to make the commercial engine, much as a larger fan was added to the F101 engine that powers the B-1 bomber to make the CFM56 series.
Having spent a lifetime working as an engineer I greatly appreciate your attention to detail and facts when discussing engineering matters. This is very much a part of our culture that, although not universal - because nothing is universal - is ubiquitous. Again, although not perfect, most engineered systems become safer and more reliable over time. This doesn't happen of its own accord, but because engineers lay awake at night worrying about safety and reliability. It's great to hear a non-engineer take considerable trouble to speak accurately about a field that is not his own.
An excellent, informative, and respectful analysis of this tragic event. It's truly a pleasure, even in these circumstances, to be able to listen to a consummate professional go through this analysis, thanks Juan.
As usual, a clear explanation with all the details. One correction re windows. The outer pane carries all the pressurisation loads. The middle pane carries no loads at all as long as the outer pane is intact. The small hole at the bottom of the middle pane is to allow the cabin pressure to be felt on the outer pane, and also gives a telltale of outer pane seal leakage. The middle pane will take pressurisation loads in the event of outer pane failure. The inner, or scratch, pane is to prevent the middle pane being scratched or damaged from within the cabin and also has holes to allow pressure to equalise across the pane.
Juan your an awesome pilot... And a great educator... thanks for giving us the straight scoop... I fly alot on both 737 NG and Airbus 319 to 321 series as well as a few SD80 and MD80 and B717aircraft. Also regularly... fly on board Embraer 175 and CRJ thanks for the information... and the respect for the woman that was hurt... you are the best thing on youtube for all what you do
The lubricant is a molybdenum disulfide lacquer spray or a molybdenum disulfide paste (GN lube) The primary hard coat on the blade Root is CU-NI-IN (Copper nickle indium) flame spray coating. Over that is a coating of "MolyDag" a Epoxy molly paint that is baked on, the the hand applied lube that is renewed about every 1000 cycles. Another minor error is the 737-200 had JT8D -9A "low bypass turbofan engines not "Turbojet engines" Great reporting as usual.
I'll start at the bare Titanium of the blade root; that is stripped of the old coatings then Eddy current inspected. (The Fan disk slots have the same process). The new Cu-Ni-IN is flame sprayed on (this is an anti galling coating as Titanium develops a protective oxide skin when exposed to air and the oxides of Titanium are very good abrasives ; nothing wears away like TI on TI ) However, when sprayed on, the coating has a relativity rough finish. The make it smooth it is coated with molly-dag which fills in the roughness and provides a long lasting wear surface. The last coating of Molly paste slows the wear rate of the CU-NI-IN. The shim shown may or not be there and is used to allow re-broaching of the disk slots while maintaining the blades original fit. As the CFM56-7B has "wide chord" fan blades, to eliminate the mid span shrouds seen on earlier models ;the blades move around in the slots a lot more than the earlier engines. Your comment on the "blade" out testing is a little inaccurate. The final testing is done in a test stand and is a "full up" test of the entire engine Inlet, reverser and all. The fan blade chosen to fail is rigged with a weakened blade root with a small shaped charge The location the blade will impact is chosen as the "worst case location and the rig is able to detonate the shaped charge at exactly the chosen location. the engine is operated at standard day rated T/O power. Success is when no engine parts leave the engine except out the inlet or out the exhaust. My thought is that the air-stream is not modeled on the "standard" failure Scenario which is Failure at Rotation. You do an incredible job covering a mired of subjects. and you are on my must watch list. Doug
Hello Juan, just read through the whole voice recorder transcript and I'd be willing to bet that you hope you;ll never have to go through something like that. I can't begin to imagine what it must be like to know that hundreds of peoples lives depend on your actions on the flight deck. Flying military planes where what, three to twelve people are depending on you would be stressful enough but hundreds? I can't begin to imagine what that must be like especially when some sort of emergency occurs. God bless Tammie Jo Shults and all of you brave people that strive to get us to our destinations safely and on time! George
I would say the lubrication of the stem of the blade is to prevent wear. You don't think any fake parts were use considering both happened in the same place, were those blades changed in the past under maintenance. Aeroplane parts that are fake is more common than you think well used to be 20 years ago I don't know if it's the same.
Unlikely any of those blades were “fake” parts. Those are very safety critical parts and are individually identified and have an unbroken paper trail that stretches almost all the way back to the dirt they dug out of the ground to make the metal in those blades. If they were found to be fake, there would have been a big deal to dig out any others which would have made it into any more of those engines. Fake turbine blades coming apart is very bad for business and airline industries reputation and bottom line.
So clear and erudite. I am a surgeon and an aviation enthusiast; i use checklists in my daily job in the operating theatre. Occasionally you need to wing it ( forgive the pun) and just remember to keep the patient alive. Hats off to the crew in this situation, saving nearly 150 lives. Also condolences to the family of the lady that died.
Very thick paste and i have seen a spray too. We usually soak the blades in isopropyl alcohol clean it off and then ndt can inspect and then relube. Its very important to maintain blade position. Everything is labelled as to where it goes. Its labor intensive and theres a lot of engines. The industry is in need of mechanics and pilots. I encourage anybody that has any interest to get involved. Its not hard. Everything in aviation has a manual telling you exactly what steps to do. Schooling was approx 15 months for a a&p. Simple math. No hard math. No english classes.
@@MrEkg98 Pilots do have some English proficiency requirements, although being native to an English speaking country will waive the testing requirement.
The thrust reverses cowls are called fan ducts. Changed a few on Alaska and Sun Country's NG's. I have replaced many blades on CFM56-3's and -7's. In the USAF the CFM-56-2b on the KC-135 when a engine on the wing is new or rebuilt from the Depot we perform a operation called a trim balance. It's more or less a vibration check, if out of balance there the computer will spit out which weights in the spinner to swap. We have after numerous attempts on some engines we call out the back shop to come out with new blades and perform a restack. Most the time it goes through with no problems but there is always that one problem child.
CFM fan blade lube comes in 2 forms paste and aerosol. Spray on is easy to apply . Spray on let dry job done. Paste is applied by hand and upon first engine run can cause fan unbalance. Cured by high power run to fling off excess paste restoring fan balance...
Juan, when I heard about the great job that the pilot had done in handling this emergency, I immediately thought of the fact that our military has terrific training. There's a lot of simulator work, and there's a lot of flying in actual airplanes that happens in order to maintain proficiency for emergencies just like this, and all of those passengers were very fortunate to have someone in the left seat that had that kind of background and experience in training. For me, it also raises the idea that in the civilian world, training costs money that has to come off of balance sheets, and especially in smaller operators, I find that training becomes something that people don't want to do because they have to pay for it, and that is one of the reasons that the smaller operations that don't have the money to spend on training only do the minimum amount that's required by regulations.... so what we need to do in the field of aviation is to make sure that training happens, and with a sufficient frequency that proficiency is achieved. I know of one air crew that was lost, and the information that I received about it suggested that they had gone to a particular training company for recurrent training and they had failed......so they went to a different training company where they passed..... and those types of things need to be prevented in our business. Without the excellent training that the pilot had, this could have actually turned out differently.
That's why we need experienced pilots flying our airliners. When something like this happens, you need to know what the feel of that airplane is telling you. Someone trained to fly the boxes just can't do that. Thanks Juan for another well thought out, fact filled update.
Juan, the area in front of the fan is an acoustic structure to help absorb the noise generated by the fan. The area directly around the circumference of the fan blades is a area, also contains core, but if filled with a light weight micro balloon filled epoxy as a wear surface. It's design is to keep the gap between the fan and case as close as possible which increases efficiency. The green part @ 4:57 is a mid cowling which is just an aerodynamic structure that allows for engine service. Aft of that is the thrust reverser. In the case of the CFM56-7, the reverser is a translating sleeve cowling which when extended pulls a set of blocker doors into the C-duct air-stream and exits through a set of cascade vanes that point forward to provide reverse thrust. The translating cowling blocker door thrust reverser is the most effective thrust reverser design.
Another great update Browne! Just a little detail, you mentioned the altitude warning horn at 14,500 feet. The warning horn comes on at 10,000 feet, the passenger masks come down at 14,000 feet.
17:05 I get why you need the trained people kept safe so they can do their job, but the optics/PR of telling a passenger to sit on the floor put pressure on them to deviate from SOP
It would be interesting to know whether the blade failed as a result of a fault in the material itself (ie, impurities in the material) or as a result of the processes used to form/machine that material propagating the crack. Thank you for your commentary and sharing what you know and what you are constantly learning Juan.
Years ago I worked at a titanium recycling facility in Richland WA & was amazed at the thousands of new looking fully machined turbine fan blades. Obviously rejected because of some flaw, most noted by the notes written on the rejected parts
Juan, Thank you so much for that video! Your explanations and attention to details were excellent. I appreciate your thoroughness, knowledge, and professionalism in these matters. God bless Paul (in MA)
Was thinking about the extra seating. You would not want to block exits or corridors, so even extra restraints that could be added galley corridors is not going to work. My only thought would be to use the lavatories as emergency seating. With added hard points for restraints that could be installed in an emergency, or have them in place. While not somewhere you may want to be, it is a seat, and it is not blocking any exits.
AgentJayZ and blancolirio have some good history together on TH-cam. I don't think they've ever done a collaboration video, but AgentJayZ did a video response to something blancolirio said a few months ago. It may have been related to this very crash, but I'm not sure. Anyway, the two know of each other and I would venture to say their relationship is friendly.
Thank you Jaun for showing respect to the woman who tragically passed away on this flight.
She was traveling on business as many of us do and left family members behind. A tragic loss.
Broke my heart when i saw her picture!! God bless her family!!
ABQ NM family..
Rest In Peace, Jennifer.
Condolences to the family.
Hi Juan, I’m a licensed engineer with an Australian airline. We’ve been carrying out fan blade re-lubes for a long time. It started in the 80’s on CF6 type engines on A300B4 aircraft in an attempt to alleviate odd N1 vibrations that intermittently plagued these engines. Very often, these inspections are carried out during overnight service where time to complete the job is an obvious factor. There is a lot of work to do. The blades can be removed in about 30 to 45 minutes. However, after removal they must be cleaned and inspected before re-lubing can be done. This is what takes all the time. It takes 10 minutes to wash each blade in denatured alcohol plus another 5 minutes to inspect. That’s 240 minutes plus 120 minutes. In addition, the fan disk must also be washed and inspected. When all is satisfactory, we re-lube the dovetails and the fan disk with two coats of spray molybdenum disulphide lubricant and wait for it to dry. It’s very easy to see how this simple procedure can quickly become a ‘rush job’ with the fan being reassembled almost as they’re waiting to tow the aircraft back on line. The tendency is to rush parts of the job: cleaning is not carried out properly making inspection more difficult. In short, it is easy to see how cracks that are potentially visible to the naked eye can be missed.
Thank you Juan for this clear and easily understandable summary of the extremely detailed and technical NTSB investigation report. I'm continually amazed at how much the NTSB can "reverse engineer" a disaster. When you said that they found that the blade failed at the 6 o'clock position, I was blown away. Anyway, thanks again for your no-nonsense reporting!
It wasn't that for me. It was the ability to envision its exit path. Lots of us who have worked with machinery have looked for witness marks from items that shouldn't meet but do. However when something has gone bang and let go in a fraction of a second and people can trace the component exit routes. That is way beyond my comprehension.
@@LTVoyager
Are you implying there is a force beyond centrifugal force at such speeds?
Chris Holt The NTSB did computer simulations using the actual design for the NG fan cowling, and found that the six o'clock impact caused forces that exceed the design criteria. A long-standing error that was only revealed by this accident, will require retrofitting of thousands of jet engines.
@@LTVoyager
Would you go so far as to say to reinforce (or less) reinforce the 6 o'clock position on the cowling as a reasonable precaution?
@@alleycatvietnam And I get frustrated when the NTSB comes up with a conclusion with no real evidence. Mostly, they do well. Also, many recommendations would cost tens or millions of dollars; in some cases, they'd render perfectly good airplanes no longer economical to fly. Aviation business runs on the edge of a razor, and often goes the wrong way.
Excellent explanation from an experienced and knowledgeable pilot.
It is why fly is so safe in this country, many of these type of investigations during the bloody years (plane designed and built from the 60s probably into the late 80s) had hundreds of minor engineering errors that were corrected. You look at the flight crash shows and many were before 2000 or planes built before 2000, many engineering and pilot corrections were done based on accidents and near accidents. The MAX accidents is an example of the type of things that happened a lot as they moved large aircraft designs developed during WW2 into passenger carriers, crashes with major airlines killing everyone were relatively common back then when compared to today and allowing people to bring or store bombs on the plane was one of those bugs.
Wow, what an amazing report Juan. This is one of your best ever. By the way if by chance you can't pass your medical, I'm damned sure that AIM would hire you as a curriculum advisor immediately.
You are really good at this. What surprised me about this whole thing was that the stewardi, gave up their jump seats, the wing lost hydraulics, and the captain focused on keeping control.
Aviate, Navigate, Communicate. All of these people are heroes!
As a physics nut, and an aviation enthusiast and former controller, with a son in pilot training, thank you sir! I love these subjects, and you do a great job at it!
Take care!
Another very informative video! Great job!. I am an AMT and have performed that blade lube on the CFM several times, although it has been years since the last lube I've been involved with. The process was done by removing all fan blades, laying them out on a large workbench, removing the old lube with alcohol, reapplying three coats of Dri-Moly lube from a spray can. Lube was applied to the dovetail of each blade, the spacer, and retainer. The blades then are reinstalled back into the engine in the same order as removed. An engine run is performed to check vibration before the next flight. This work was done on a routine "B" check overnight, one engine at a time. A visual inspection was accomplished but no NDT was involved.
Thanks Robert!
blancolirio Juan as a 30 yr AMT @ UAL I would like to add to Mr. Behring”s statement that at UNITED ultrasound inspections are performed on each fan blade in addition to a DETAILED VISUAL INSPECTION of the fan hub assembly. Keep up the good work gents.....
Just read entire com, CVR. She did an amazing job not fully realizing what was wrong until on the ground. Thank God she (and FO) had the experience to make good decisions, despite scrapping checklists. To much going on. We all learn it early on -- Fly the Airplane, Fly the Airplane, Fly the Airplane. If necessary, fly it all the way through the crash sequence.
Lubricant is very thick grey lubricant of graphite grease so once they are removed they have to be stored in a specific sequence so that once they are reinstalled and run they will meet the vibration limits. This paste prior to inspecting the blades have to be thoroughly cleaned, then inspected then lubed again and installed lots of work.
They likely self center via centrifical forces, the lube assists it.
I would love to do that, but then I wouldn't be able to sleep at night anymore...
Another "home run" Mr Juan!! You keep knocking them out of the park one after another!! Always learning tons of cool aviation stuff from your great videos!! Muchas gracias!!
Juan, your best one yet. Kudos to this fine crew again, the flaps 5 call and speed was a great call on their part. Max brakes will stop a 700 at 180 knots in Philly no problem.
Professionals in the cockpit, and Juan to communicate clearly just why that matters. Great video!
Love it Juan. Great information. As the former ALPA Air Safety Chairman for my airline, you should wind up at the NTSB or start your own consulting company. I know John Cox from USAirways did this.
Juan, I'm not a pilot nor am I involved in air travel. I just wanted to say your presentation is so spot-on that I enjoy listing to you. You are a treasure! YT should feature you and your presentations as an example of how to correctly deliver content.
Thank You Juan for such a detailed and professional explanation. My heartfelt condolences to the family.
Heartfelt video, especially near the end -- our condolences to Jennifer Riordan's family. Kudos to the crew for doing all they could to land safely. Thx for the detailed explanation, Juan. Take good care!
Yes, who else was triggered by that sparse but calm piano?
Maestro, your videos are like a symphony of tecnical details and logic. Bravo.
She was the right captain to have on that flight at that time. Her experience as a Naval fighter pilot was a great asset to have in this situation. If you go to the Flight Channel and search for SWA 1380 you will see a flight simulation of what happened and hear the radio transmission. Condolences to the family of the passenger that died.
The level of detail in your videos continues to impress me. Also I keep learning how amazing the flight crew is on your average airliner. And, the unsung heroes are the cabin crew.
Excellent video!
Thanks Jay!
The flying public DEMANDS only the most competent top guns up front. Anything less is criminal. They don't deserve applause. It's their job.
@@jimallen3392 But there’s nothing wrong with giving kudos for a job well done, in any field. Frankly, the flying public could stand to do a better job, by actually paying attention to the safety briefings, following crew instructions, not being disruptive, etc. (in general, I mean; seems like the folks on this flight did fairly well).
@@blancolirio oo8j9[
@@jimallen3392 👍
You my friend, are a class act! No BS, straight to the point reporting as usual. Many thanks Juan for your contribution to this industry.
If you ever decide to hang up the wings, I'll bet the NTSB would love to get someone such as you on staff Juan. A 'hobby' becomes work type of thing. Hmmm
Excellent, fact filled report here. Thanks 👍👍
I agree Juan has the respect of the aviation industry and a growing public image, exactly the type of person needed to convey in terms understood by 'laymen' the findings or otherwise of the NTSB.
Supreme court of the airline industry.
He should have 1M subs within 2 years. At that point, he'll be viewed more than the NTSB at their preas releases. It would do the NTSB good to have them as their PR guy. It would do news oulets good to have them as a talking head when anything aviation related goes down, but youtube is still a big threat to most MSM.
I'll second that!
I will chime in here. too. Juan does his research, AND speaks in pilot terms of course...so maybe as a pilot I might be biased because I know what he's saying? BUT? I think the layperson can understand what Juan says and explains.
Excellent report Juan. You have a great talent for analyzing these events and relaying the facts to those of us who know nothing about the mechanics of jet engines, but are willing to listen.
Thank you for the link to the transcript. Quite a moment when the Captain mutters, ''Heavenly Father.' The crew deserves praise for a job very well done!
I was totally captivated by your explanation of the NTSB findings. An excellent tutorial. I hold an A&P certificate.
He does also!
Juan, All that I find surprising is that you do not have more followers. Another report hit out of the park, clear, concise and in a way that the less technical of us can easily follow. Thank you, for all of your reports, on so many subjects!
ginvr TH-cam does not promote these kind of videos, due to the 'sad' content which does not attract advertiser revenue.
I have zero aviation experience yet I find your explanations so easy to understand. I pray that every commercial pilot I fly with has the depth of caring and knowledge that you have Juan! You are doing a fantastic job and I think you should be considered for a NTSB chairperson!
“…speed is life.” Excellent.
Actually that's almost the opposite of what the judge said today in traffic court :-(
@@Miata822 😆
efox2001 I recently learned the term “moose stalls”. Apparently the term was coined in Alaska because of stall-spin crashes by pilots doing turns around moose while either observing or hunting them and the plane gets too slow for the bank angle (a higher speed stall) and they are unable to recover because of the low above ground altitude.
Bruce John Shourt Juan left out the 2nd part:
Speed is life, and altitude is life insurance (corrected).
Nice touch at the end. Very respectful.
Wow, Juan you have such a passion for this industry and we are all safer for it! Thank you!
Much respect to the crew!!!!! Thank you for all your training !
Thank you, Juan for this update. Condolences to the family of Jennifer Riordan.
Great breakdown and explanation. I think it would be difficult for a flight attendant to tell pax to vacate the jump seat and sit on the floor so crew can be seated. Maybe they could find a way to add a 4th belt to certain rows and squeeze some skinny people together for emergencies. BTW, the flight # is transposed in the title.
Thanks!
ShooterReady...I can hear it now....flight attendants are sued for discrimination because they judged some passengers to be fatter than other passengers..OH MY..!! Don't tell CNN, they will pounce on this and run with it for 6 months..!!
That conflict (a flight attendant having to tell a passenger that the FA is more important than the passenger) was noted, at least during the hearing. However, it should also be noted that in this incident, _nobody_ was seated in the forward jumpseats during landing. There was room for two of the flight attendants to sit there, and the third could've pushed the deadheading employee out of one of the aft jumpseats. I'm not judging... there must've been a lot of chaos in the cabin, and the landing occurred much sooner than expected (after the flight crew was advised of the passenger's condition). But I think the NTSB is right to suggest that FAs be reminded that it's crucial that they be seated and strapped in during landings, especially emergency landings.
@@DougPardee This situation reminds me of the protocol if the oxygen masks have to be used and their is a child sitting next to it's mother or an adult. The protocol is for the mother/adult to put their oxygen mask on first and then putting the child's mask on them. The reason, I think, is that if the adult were to try and get the child's oxygen mask on first, there could be the chance that the adult could pas out before being able to get it on the child and both could suffer oxygen deprivation, or worse, as a result.
I know that technically the flight attendants should have been in their jump seats, but really, can you imagine kicking out traumatized passengers so they can sit in safety? Sometimes you need to make judgement calls appropriate to the situation.
Good job by the crew. They flew the jet, no panic.
Thanks Juan, we’ve all heard the ATC communication aboard this flight and saw the aftermath of the destruction. Today I have a much better understanding of the horror in the cockpit. The crew did a great job, considering the totality of the failures and the lack of time to comprehend them. 👍🏻👍🏻
The outer pane is taking all the pressure. Its the main structural element. The middle pane has the hole in it. Its just a backup. Either pane can take the pressure. The inner pane keeps the passenger rash off the middle and outer. The inner pane has no hole. I have assembled quite a few.
A reminder for anyone traveling on a plane. If you see the inner pane coming out from the sidewall. Please do not be alarmed. The inner pane is just trim and a very thin plastic window. Its there to keep passengers from scratching the real window. Nothing structural. Kindly let a flight attendant know after the flight is over and line maintenance can address the the issue.
Thanks again Juan for your fine reports like this. So much more than what I can find elsewhere.
As always, thank you for your clear, concise, no nonsense explanations. We appreciate the effort you obviously put into these reports and the respect for the victims. We’re praying for your return to excellent health!
The passenger cabin windows are one piece They are larger than the window opening the widow is held in position with clips and the cabin pressure keeps them sealed against the inner skin. the panel on the inside is approximately 1/16 inch thick and is part of the cabin interior decorative side wall. the entire interior side wall panel is easily removed . The function of the inner panel is to keep passengers from scratching the inside of the pressure window with sharp objects and diamond rings because scratches will create stress riser, which could cause the window to fail. the other purpose is provide a cavity between the inner and outer windows for cabin air to keep the outer window defrosted. the small hole is to allow that cabin air to bleed back into the cabin.
Great information. I’ve worked on these windows and Engines for more than 30 years.
Again just an excellent explanation of a very involved issue. You just amaze me with your ability to explain very technical issues in a manner most every one can understand. Keep up the good work. Thanks
Easily one of your best videos. Thank you! This video pushed me over the patreon cliff. See you there.
Thank you, Juan. Your experience, knowledge, and dedication in all the work you put into this channel are a great service to aviation. You dig in and explain so that we may try to follow and understand. With deep appreciation from a pilot with a shortened career, who follows your schedules and inquiries, /romain (Continental Airline, 1966-1981, Captain and Check Airman, 1977-1981; Sr. Pilot, USAF, SD and Cal.ANG, 1957-1971)
As a product designer, I'm stunned at the image of people with the mask only over their mouth and not their nose. Note to the designers of these systems: All you have to do is add a small nose-shaped indentation in the rim of the cup and that will automatically tell people to cover their nose. Yes, you'll have to redesign the mould. Yes, the mould will be slightly more expensive. Yes, people WILL use the oxygen mask correctly as a result.
Great explanation of the NTSB findings Juan. The crew did a great job given the multiple problems that they were faced with they got the plane down quickly and choosing a fast landing rather than extending unknown stuff into the wind on an aircraft that was displaying wonky handling was a good call given the long runway. Anyway, thanks Juan for the as always detailed briefing from a pilot's point of view, way more informative than a reporter with no airline knowledge.
Thank you Juan for your passion and tribute to Jennifer, who lost her life. It's easy to "just do your job". I know my friends and relatives who pilot are like you. Airline pilots are still a breed apart for the most part and I am thankful every time I fly.
Thanks for the in-depth explanation of this event. It was a lot more complicated than I had realized. My compliments and admiration to the flight crew, in their handling of the situation. Makes me, worried about future flights with the pilot shortages and the low time aircrew coming on line. I am afraid that not only inexperienced, but they don't fully understand what they are doing.
Very well done Juan... and it's good to be reminded of the professionalism of all our pilots, especially USN & USAF (I'm watching this on a challenging day -12/6/19)
As usual, you add to my list of skills to help keep myself calm during an emergency and trust the flight professionals, fore and aft, to do whatever can be done to
get us all on the ground safely. You are still contributing a lot to the industry, even during your furlow. Thanks.
Congrats on such a fabulous upday Juan...so much information presented so a layman can understand. Thanks for that. So sad this woman lost her life...RIP
Great to have honest reporting, that in itself carries a great respect, keep it up and have a Merry Christmas.
Thanks Juan for the great explanation and expert insights into a complex and difficult accident. I appreciate the way you make this information accessible to those of us who aren’t professional airline aviators.
This is my fist time to comment a video ever. Great job on presenting facts, lessons learned, combined with respect to the the victim of this incident. Hat off for you
Brilliant explanation, so well explained. Juan, if you ever get the time to write, a book from you would be a 'must have'. There would be a lesson in it for everyone.
I'm beginning to see a pattern in complex aircraft emergencies. Emergency checklists are practically useless. Emergencies are chaotic, and can't be rehearsed. Aviate, navigate, communicate. Also, delegate! One pilot should fly the plane, the other should handle the rest.
Emergency checklists and training assume a textbook scenario. They are useful in that they give very good guidance in situations that, if incorrectly handled, can become very chaotic indeed. EXPERIENCE, however, is the factor that determines weather the checklist/recurrent training guidance is applicable in non-textbook scenarios such as this one.
The vast majority of non-normals are simple, textbook scenarios that work very well with checklists. Very little experience required. These non-normals happen every day and don't make the news as they are non-events.
Multiple unrelated failures rely on the experience of the pilots to do the right thing given the scenario. We are very lucky in North America that we still have very experienced pilots flying our airplanes. In the case of SW 1380, an inexperienced crew may have been the catalyst to a very large disaster indeed.
YOU GET WHAT YOU PAY FOR!
Right. Remember this every time some bozo talks about "pilotless airliners."
You are clearly wrong. It is directly because of emergency checklists practiced over and over again that directly resulted in the pilot correctly managing and responding automatically and correctly to multiple emergencies without having to refer to the checklist. But because she practiced these emergencies and checklists many times she knew exactly how to react and what to do without referring to a checklist and utilizing parts of checklists automatically that helped her emergency, saved the plane, passengers and crew directly because checklists exist and were practiced. Agsin your dead worng, check lists are critical
@@n6mz Very well said. DIA installed a very expensive automated baggage handling system that never worked. Robots are good for redundant tasks, but are complete failures with the unexpected. All tjhey do is shut down. The MCAS system is a good example.
@@n6mz I do think about this. A computer would be able go through a checklist almost instantly (and continously) and never forget anything or do it in the wrong order.
Thank you for another amazing report. Main stream media just can’t dedicate such time to an amazing report. Nor would they find it news worthy. But you do and that’s why we appreciate the time you put into sharing and educating all of us....
Juan, thanks for taking a complex topic of great importance and explaining it in clear, understandable terms. The graphics also help to see where the parts are located and to see the damage after knowing where everything fits together. Great job as always. Thanks!! - Dean from Minnesota
The amount of research, testing and resulting complexity of airliners never cease to amaze. It's sad that these masterpieces of engineering are often taken for granted.
I'm really impressed by your to-the-point delivery and content quality. Even if your clips were 1 hour long, they'd seem too short.
When the defecation hits the rotating oscillator....you want a Naval Aviator or Air Force Pilot in the pointy end!
Just listened to her CVR, cool as ice.
In addition to Air Force and Navy pilots, I have worked with Marines who fly and manage a crew exceptionally well. I’ve also worked with civilian pilots who are easily at the same level. The learning never stops. It is the personality that determines the result, not the source of the initial training.
Nice creative writing, but fan blades don't oscillate. Need to come up with something better. Maybe "when the fan blades break and puncture the defication holding tanks, you want a Naval carrier pilot controling the yoke."
@@pawswet9476 Marine pilots are trained by the Navy. Navy and Marine pilots are basically the same just different uniforms and missions. The vast majority of the ones I have worked with in my 42+ years in aviation are top notch and would fly with them anytime, anywhere, under any circumstances.
I was a ship's company officer on a carrier during Vietnam. Watching the planes land on a moving, bobbing, very short deck that is at an angle to the direction of travel, at night .... adds another level of skill, required concentration … I always thought other pilots should at least get a cockpit ride onto a carrier just for the experience. Juan??
I learned so much from your report. Thank you for the context you provided and carefully described for each of the multiple and simultaneous emergencies. I can only react with enormous respect for the crew, the engineers and crafts persons who design and manufacture the parts, and having your level head, practical experience and voice that broadens our view and understanding.
Thanks Juan for the excellent report on the NTSB report. It's great info and from a commercial pilot's perspective.
The clanking sound while the blades are windmilling is coming from a midspan shroud. Theres a little raised protrusion in the middle of the blade. This keeps the blades in relative position and lowers stress on the root. The blades actually sling outwards in the hub. The blade arrangement expands ever so slightly once at speed. The lube helps the blades seat in the dovetail. This arrangement also has a abradeable material near the tips on the case. The case is there hold this material. This material is cut by the blades at initial runup of the engine. It provides a positive seal between the tip of the blade and the case. It makes it so you dont have air pressure leaking past the outside of the blade. Just like a winglet tries to limit the vortex. This material completely eliminates the vortex. Makes the engine more efficient and highers the compression ratio.
Thanks ekg!
I listened to this vlog first, watched it second. Excellent work Juan. Thank you.
Great job, Juan. I usually get my info from reading these reports, but I very much enjoy your take on them. One correction based on your comment at 5:09: The 737-100 and 200 were powered by P&W JT8D turboFAN engines, albeit low bypass by today's standards. The JT8D was based on the military JT8, military designation J52 -- an actual turboJET that powered the A-4D and later series as well as the A-6 series and the Hound Dog missile. A fan was added to make the commercial engine, much as a larger fan was added to the F101 engine that powers the B-1 bomber to make the CFM56 series.
Having spent a lifetime working as an engineer I greatly appreciate your attention to detail and facts when discussing engineering matters. This is very much a part of our culture that, although not universal - because nothing is universal - is ubiquitous. Again, although not perfect, most engineered systems become safer and more reliable over time. This doesn't happen of its own accord, but because engineers lay awake at night worrying about safety and reliability. It's great to hear a non-engineer take considerable trouble to speak accurately about a field that is not his own.
GREAT Video! Lots of interesting detail. Fabulous job as always Juan.
An excellent, informative, and respectful analysis of this tragic event. It's truly a pleasure, even in these circumstances, to be able to listen to a consummate professional go through this analysis, thanks Juan.
As usual, a clear explanation with all the details. One correction re windows. The outer pane carries all the pressurisation loads. The middle pane carries no loads at all as long as the outer pane is intact. The small hole at the bottom of the middle pane is to allow the cabin pressure to be felt on the outer pane, and also gives a telltale of outer pane seal leakage. The middle pane will take pressurisation loads in the event of outer pane failure. The inner, or scratch, pane is to prevent the middle pane being scratched or damaged from within the cabin and also has holes to allow pressure to equalise across the pane.
Juan your an awesome pilot... And a great educator... thanks for giving us the straight scoop... I fly alot on both 737 NG and Airbus 319 to 321 series as well as a few SD80 and MD80 and B717aircraft. Also regularly... fly on board Embraer 175 and CRJ thanks for the information... and the respect for the woman that was hurt... you are the best thing on youtube for all what you do
The lubricant is a molybdenum disulfide lacquer spray or a molybdenum disulfide paste (GN lube) The primary hard coat on the blade Root is CU-NI-IN (Copper nickle indium) flame spray coating. Over that is a coating of "MolyDag" a Epoxy molly paint that is baked on, the the hand applied lube that is renewed about every 1000 cycles.
Another minor error is the 737-200 had JT8D -9A "low bypass turbofan engines not "Turbojet engines"
Great reporting as usual.
Thanks Hitech. What is the purpose of the lube? vibration? protection?
I'll start at the bare Titanium of the blade root; that is stripped of the old coatings then Eddy current inspected. (The Fan disk slots have the same process). The new Cu-Ni-IN is flame sprayed on (this is an anti galling coating as Titanium develops a protective oxide skin when exposed to air and the oxides of Titanium are very good abrasives ; nothing wears away like TI on TI ) However, when sprayed on, the coating has a relativity rough finish. The make it smooth it is coated with molly-dag which fills in the roughness and provides a long lasting wear surface. The last coating of Molly paste slows the wear rate of the CU-NI-IN. The shim shown may or not be there and is used to allow re-broaching of the disk slots while maintaining the blades original fit. As the CFM56-7B has "wide chord" fan blades, to eliminate the mid span shrouds seen on earlier models ;the blades move around in the slots a lot more than the earlier engines.
Your comment on the "blade" out testing is a little inaccurate. The final testing is done in a test stand and is a "full up" test of the entire engine Inlet, reverser and all. The fan blade chosen to fail is rigged with a weakened blade root with a small shaped charge The location the blade will impact is chosen as the "worst case location and the rig is able to detonate the shaped charge at exactly the chosen location. the engine is operated at standard day rated T/O power. Success is when no engine parts leave the engine except out the inlet or out the exhaust. My thought is that the air-stream is not modeled on the "standard" failure Scenario which is Failure at Rotation.
You do an incredible job covering a mired of subjects. and you are on my must watch list.
Doug
Excellent video Juan!! Thank you for your research and preparation to present this video. Great work!
excellent thorough review Juan. Thank you for your time and diligence in reporting
Thanks again Juan for an informative report.
Thanks, Juan. I always appreciate your thoroughness and how you make it easy to understand.
Once again Warren your Report is Qualified and concise . Thank you so much .
Hello Juan, just read through the whole voice recorder transcript and I'd be willing to bet that you hope you;ll never have to go through something like that. I can't begin to imagine what it must be like to know that hundreds of peoples lives depend on your actions on the flight deck. Flying military planes where what, three to twelve people are depending on you would be stressful enough but hundreds? I can't begin to imagine what that must be like especially when some sort of emergency occurs.
God bless Tammie Jo Shults and all of you brave people that strive to get us to our destinations safely and on time!
George
Cargo planes can hold hundreds of troops
You do an excellent job of explaining everything, thank you.
Extraordinary report! It is amazing how much one learns. And the emotional tribute to the crew and to the unfortunate passenger. Congratulations Juan.
I would say the lubrication of the stem of the blade is to prevent wear.
You don't think any fake parts were use considering both happened in the same place, were those blades changed in the past under maintenance.
Aeroplane parts that are fake is more common than you think well used to be 20 years ago I don't know if it's the same.
Unlikely any of those blades were “fake” parts. Those are very safety critical parts and are individually identified and have an unbroken paper trail that stretches almost all the way back to the dirt they dug out of the ground to make the metal in those blades. If they were found to be fake, there would have been a big deal to dig out any others which would have made it into any more of those engines. Fake turbine blades coming apart is very bad for business and airline industries reputation and bottom line.
Thanks Juan, for making the complicated a little easier to understand.
Outstanding video sir and much respect ! Stay safe sir.
Awesome report and informative context! Thank you, Juan...
I am sorry Juan - tough one. Stay safe.
Nicely done. The seating issue is going to be a tough one to solve.
When the fan hits the stuff
Hornet135. That was a pretty bad dad joke. I gave you a thumbs up. I would have said the same thing. LOL
I thought the same thing, haha
Don't you just hate when the stuff hits the fan.
J Hutch not sure how it was a dad joke though, thought it was more ironic than anything.
So clear and erudite. I am a surgeon and an aviation enthusiast; i use checklists in my daily job in the operating theatre. Occasionally you need to wing it ( forgive the pun) and just remember to keep the patient alive. Hats off to the crew in this situation, saving nearly 150 lives. Also condolences to the family of the lady that died.
Last time i lubed blades i believe it was a dark grey moly type lubricant.
Very thick paste and i have seen a spray too. We usually soak the blades in isopropyl alcohol clean it off and then ndt can inspect and then relube. Its very important to maintain blade position. Everything is labelled as to where it goes. Its labor intensive and theres a lot of engines. The industry is in need of mechanics and pilots. I encourage anybody that has any interest to get involved. Its not hard. Everything in aviation has a manual telling you exactly what steps to do. Schooling was approx 15 months for a a&p. Simple math. No hard math. No english classes.
@@MrEkg98 Pilots do have some English proficiency requirements, although being native to an English speaking country will waive the testing requirement.
Another well thought out explanation of the events, thank you for your hard work Juan. RIP Jennifer Riordan, bless her Family
Great explanation Juan. It is amazing what we know compared to what there is yet to learn. Sometimes tragically.
The thrust reverses cowls are called fan ducts. Changed a few on Alaska and Sun Country's NG's. I have replaced many blades on CFM56-3's and -7's. In the USAF the CFM-56-2b on the KC-135 when a engine on the wing is new or rebuilt from the Depot we perform a operation called a trim balance. It's more or less a vibration check, if out of balance there the computer will spit out which weights in the spinner to swap. We have after numerous attempts on some engines we call out the back shop to come out with new blades and perform a restack. Most the time it goes through with no problems but there is always that one problem child.
CFM fan blade lube comes in 2 forms paste and aerosol.
Spray on is easy to apply . Spray on let dry job done.
Paste is applied by hand and upon first engine run can cause fan unbalance.
Cured by high power run to fling off excess paste restoring fan balance...
Juan, when I heard about the great job that the pilot had done in handling this emergency, I immediately thought of the fact that our military has terrific training. There's a lot of simulator work, and there's a lot of flying in actual airplanes that happens in order to maintain proficiency for emergencies just like this, and all of those passengers were very fortunate to have someone in the left seat that had that kind of background and experience in training.
For me, it also raises the idea that in the civilian world, training costs money that has to come off of balance sheets, and especially in smaller operators, I find that training becomes something that people don't want to do because they have to pay for it, and that is one of the reasons that the smaller operations that don't have the money to spend on training only do the minimum amount that's required by regulations.... so what we need to do in the field of aviation is to make sure that training happens, and with a sufficient frequency that proficiency is achieved.
I know of one air crew that was lost, and the information that I received about it suggested that they had gone to a particular training company for recurrent training and they had failed......so they went to a different training company where they passed..... and those types of things need to be prevented in our business. Without the excellent training that the pilot had, this could have actually turned out differently.
That's why we need experienced pilots flying our airliners. When something like this happens, you need to know what the feel of that airplane is telling you. Someone trained to fly the boxes just can't do that. Thanks Juan for another well thought out, fact filled update.
I‘m convinced the Ethiopian passengers would have wanted more experienced pilots as well.
Juan, the area in front of the fan is an acoustic structure to help absorb the noise generated by the fan. The area directly around the circumference of the fan blades is a area, also contains core, but if filled with a light weight micro balloon filled epoxy as a wear surface. It's design is to keep the gap between the fan and case as close as possible which increases efficiency.
The green part @ 4:57 is a mid cowling which is just an aerodynamic structure that allows for engine service. Aft of that is the thrust reverser. In the case of the CFM56-7, the reverser is a translating sleeve cowling which when extended pulls a set of blocker doors into the C-duct air-stream and exits through a set of cascade vanes that point forward to provide reverse thrust.
The translating cowling blocker door thrust reverser is the most effective thrust reverser design.
Another great update Browne! Just a little detail, you mentioned the altitude warning horn at 14,500 feet. The warning horn comes on at 10,000 feet, the passenger masks come down at 14,000 feet.
Ahh! Thanks! You are correct.
17:05 I get why you need the trained people kept safe so they can do their job, but the optics/PR of telling a passenger to sit on the floor put pressure on them to deviate from SOP
It would be interesting to know whether the blade failed as a result of a fault in the material itself (ie, impurities in the material) or as a result of the processes used to form/machine that material propagating the crack. Thank you for your commentary and sharing what you know and what you are constantly learning Juan.
Years ago I worked at a titanium recycling facility in Richland WA & was amazed at the thousands of new looking fully machined turbine fan blades. Obviously rejected because of some flaw, most noted by the notes written on the rejected parts
Juan,
Thank you so much for that video! Your explanations and attention to details were excellent. I appreciate your thoroughness, knowledge, and professionalism in these matters.
God bless
Paul (in MA)
Was thinking about the extra seating.
You would not want to block exits or corridors, so even extra restraints that could be added galley corridors is not going to work.
My only thought would be to use the lavatories as emergency seating. With added hard points for restraints that could be installed in an emergency, or have them in place.
While not somewhere you may want to be, it is a seat, and it is not blocking any exits.
Excellent overview of the entire incident keep up the good work and thank you for your insite.
"AgentJZ" is good channel about engine topics.
@ ty
@ thanks for the correction.
AgentJayZ and blancolirio have some good history together on TH-cam. I don't think they've ever done a collaboration video, but AgentJayZ did a video response to something blancolirio said a few months ago. It may have been related to this very crash, but I'm not sure. Anyway, the two know of each other and I would venture to say their relationship is friendly.
Juan, this is a great presentation. Thank you, brother.
Excellent and thorough analysis and explanation of the events and data. Thank you.
I worked for SWA from 1983 until 2009 and everyday I wish I was still there.