At request of the safety reps, Eurocopter have prepared this 5 minute video that explains the key manufacturing processes of the Bevel Gear Vertical Shaft.
You would not believe something so big could be built with such precision, I worked in a factory that supplied aeronautical components ,the attention to detail is phenomenal ,the thought of one months work at a cost of millions not passing final inspection and end up being scrapped concentrates the mind.The manufacturing engineers and assembly mechanics are not your average Joes
Yeah, there is a good reason why manufacturing for this particular gear is explained. That weld is messed up properly. 10 May 2012: G-REDW, an EC225 LP, carried out a controlled ditching following indications of a failure of the main gearbox (MGB) lubrication system and a subsequent failure indication warning on the emergency lubrication system. An investigation by the Air Accidents Investigation Branch (AAIB) identified a 360° circumferential crack in the bevel gear vertical shaft in the main gearbox, in the vicinity of a manufacturing weld, causing disengagement of the drive to both mechanical oil pumps.[70] 22 October 2012: G-CHCN, an EC225 LP of CHC Scotia, ditched in the North Sea 32 miles south west of Shetland whilst en route from Aberdeen to the West Phoenix drilling rig. All 19 on board were rescued. A special bulletin issued by the Air Accidents Investigation Branch (AAIB) said the main and standby oil pumps were not working; a 360-degree crack found on the bevel gear vertical shaft of the gearbox had prevented the oil pump gears from being driven. A worldwide grounding of the type was initiated in response.[35] In both of the 2012 incidents, although the main gearbox lubrication system had failed, the backup system was working correctly but displaying an erroneous warning light, due to an incorrect specification of a pressure switch, which led to the helicopters being ditched.[71] 29 April 2016: LN-OJF, an EC225 LP of CHC Helikopter Service, crashed at an islet near Turøy in the Bergen archipelago, en route to Bergen Airport, Flesland, from the Gullfaks B platform in the North Sea. The helicopter was carrying 11 passengers and 2 crew members; there were no survivors. Eyewitnesses reported that the main rotor separated from the hull immediately before the crash. Due to the crash, all commercial flights by EC225 helicopters, excluding search and rescue flights, were grounded by both Norwegian and British civil aviation authorities.[72][73][74]
2018/7/17 korean marine helicopter (MUH-1, surion variant, developed by airbus helicopters, used same gearbox with super puma) crashed due to gearbox problem. maker of this gear, "Aubert ＆ Duval" admitted they did wrong about cooling processes of the gear. it had to be air cooled, but they used water which made strength degradation.
yep, and I loved AH presentation on EASA Rotorcraft symposium couple of years ago. To protect you from our MGB problems we will forbid you to repare it any where else but AH fascilities and TBO and other maintenance periods will make shorter... much shorter. We love our customers=)
It actually impressed to think of that the gear set is made to reduce the speed and increase the torque coming from the engines and yet the rotor spins like crazy at speed.
"Non-destructive testing" is what you do to ensure that "production" parts are made "correctly" when "finished" AFTER developing the "manufacturing process" using DESTRUCTIVE TESTING OF "PROTOTYPE PARTS" and even then you still keep DESTRUCTIVELY "TESTING" PRODUCTION PARTS TO MAKE SURE "FAMILIARITY" HASN'T TURNED INTO "COMPLACENCY".
Thank the engineers back in the 40's with slide rules and sand casting. Absolute geniuses back in that era. Absolute gorgeous Shaft Gear. Easily $25k for that one part.
Playa you are 100% right slide rules I was a tool maker in Detroit back in the day hated running this machine it was hot dirty but I loved the smell of the factory. Now gears are produced on CC machines I work on machines that make drugs far cry from Detroit and the auto factory But I am at the end of my time except in Florida they are building a steel factory in Frostproof. Florida I hope they will hire a old dude like me. They are from North Carolina and hiring and will put people to school have a good day be safe.
@@nickleggett2101 Big 3 family here too. Tool and die, etc...That machine shop smell: High sulfur cutting oils, Chlorinated solvents all that, agreed. Pill press machinery or actual reaction vessels and stuff?.. Nothing replaces experience. The fact you type fluently and understand manual machining, you Will get your new job. Make sure to include all those attributes in your resume and willing to study.. I had the people at the career center help me with mine, was hired the next day lol. I love all of central Fla. I miss it.. You have a great day too Nick, good luck on that dream job okay. Get out their on one of those lakes and soak up the fresh air for me too eh.. Peace
@@flaplaya got your tx Monday morning thank u for the encouraging remarks it's good to hear from a brother from the old school of machining where backlash of .020 or more was a part of the day to day grind I live about 6 miles from treasure island beach I think I will go there today. Be safe take care and have a good day.●●●●●●●.
@@nickleggett2101 Twenty thousandths worked. 20 microns nowadays is just amazing.. Treasure Island near Clearwater? That's all deep sea charters and an amazing stretch right through there... Great to see others encouraging, positive additives as well. Hope you had fun I went freshwater fishing on Ft Loudon Lake caught one stripper it was nice. Keep enjoying life.. I'm teaching that buddy how to run a 60 year old Craftsman mini lathe. Belt driven and that little thing was built well. Feed screw with all the SAE ratios and everything. Pretty neat machine.
@@flaplaya got your message this am thanks Yes treasure island is about 15 minutes. From Clearwater beach but beach is to small and new large hotels put more people in a high tourist area, it's a hot spot for spring breakers. Now on this cool old lathe have fun surprised the motor still runs but things were made to last back in those days, old finds like that one could bring the owner some quick cash just keep her oiled and do not use air hose to blow off the chips it could jam the carriage and drive screws . Have some fun. Good day.
The gearbox is the weak link in a helicopter. Always has been lubrication of the system is vital. Rotation and identity numbers on the components within the gearbox should be part of the service history.
We did a lot of EB (electron beam) welding of rocket motor casings (high strength 4135 steel) back in the late 1980’s at Goodyear Aerospace in Akron, Ohio. That EB weld on the ring gear did NOT look very robust to me.
@@JimLem To be fair, videos of this kind will tend to draw one of two types of people, random curious people and people who're familiar with the processes involved who want to see how it is done in other settings.
@@jimmydesouza4375 I agree, but I'm not sure how that relates to my comment. Eurocopter (or Airbus Helicopters as they're now known) is a very well established aerospace brand which has been around for decades. They spend billions on research and development. Yet one self-proclaimed expert viewing a poor quality video clip thinks they have it all wrong.
@@JimLem I work for the largest insulation manufacturer in the world, that has been around since the 17th century, that has been making fiberglass since the 1920's. The factory where I work bursts into flames due to improper process at least 20 times a year and we get approximately 4% of our shipped output returned due to flaws that are not detected. Of course, we don't have the same QA standards as an airbus factory, but just because something is established and spends billions doesn't mean there can't be flaws.
@@jimmydesouza4375 I didn't say that either. I simply stated that it's absurd to think you can provide a professional opinion on something you've seen in a poor quality video clip. Your example with two factory fires a month isn't the same thing. Most businesses would investigate what went wrong the first time, then implement steps and processes to minimise the risk of it happening again. If you know procedures are not being followed, yet nothing is being done to correct that, that's just blatant irresponsibility. I'm pretty sure Airbus don't employ a "It's fine, it'll do" attitude. Failures occur. They make improvements to minimise repeated failures.
I was on one of these choppers when the bevel gear failed and it ditched in the North Sea (g-chcn) the part has now been redesigned but only time will tell if it works.
The Hughes Helicopter and Enstrom has one of same dimensions as this showed in video , the gears of the Hughes is manufactured per great company General Eletric in USA.
BOMTOGL. Unimpressive tensile test at 49sec. The test specimen necking outside the extensometer test zone. Tensile tests are usually only considered valid if the break is in the middle third of the test zone between the extensometer points. Broke Outside Middle Third Of Gauge Length. BOMTOGLE.
This vertical bevel gear shaft was redesigned after 2 accidents in 2012 and replacements should start medio 2014. Today a terrible accident in Norway with an EC225 (LN-OJF) heading home from an offshore rig. 13persons killed.. (: R.I.P. I indeed hope the new modified part was onboard.
That's not a "two-piece gear" unless they're "friction welding" the "pieces" together post-machining of the "ring gear". If those "genius" engineers would simply use a "bolt-on" ring gear and carrier and treat that rotor gearbox like a simple "differential" ring & pinion set-up in the axle or transaxle of any and every "land vehicle" bigger/more complex than a motorcycle or "trike" built whether on tires or tracks, they wouldn't need those fancy "surface grinder" stones to "machine" gear teeth because they wouldn't have to BE that "precisely" finished and ground. When dealing with a RING AND PINION SET the "final machining" is done BY THE PARTS THEMSELVES. They could properly "match" the ring gear and its pinion(s) before assembly and let the parts lap and "finish machine" each other BEFORE the whole gearbox is assembled and its too late to properly inspect and observe the "break-in" process. And if that "chrome plated" gear is for anything but a "cutaway display" gearbox its no wonder "Eurocopters" have so many "gearbox" failures and crashes. You don't CHROME PLATE POWERTRAIN PARTS BECAUSE CHROME PLATING "HARDENS" THE SURFACE OR RATHER ADDS A "HARDENED" SURFACE TO THE EXISTING "STEEL" AND THAT CHROME SURFACE IS FAR TOO THIN AND BRITTLE AND "RETAINS" STRESSES IN THE METAL ITS PLATED ONTO AND WILL "FRACTURE" INEVITABLY WHEN SUBJECTED TO HIGH "UNIT LOADS" AND IT ALSO DOESN'T "RETAIN" LUBRICANT PROPERLY AND WILL LET HEAT "IN" TO THE GEAR BUT WON'T LET IT BACK OUT. And if they have to "vacuum remelt" the "steel" before making their "blanks" they're using RECYCLED "steel" and that is EPIC STUPIDITY AND ENGINEERING IDIOCY AT ITS FINEST. USING "RECYCLED" STEEL FOR "CAST IRON" CASTINGS AND "LOW-LOAD" PARTS IS ONE THING. AND EVEN THEN IT NEEDS TO BE VERY PRECISELY "MIXED" TO PRODUCE "NODULAR IRON" OF THE PROPER "TYPE". BUT YOU NEVER "RECYCLE" STEEL/IRON FOR SOMETHING LIKE GEARS OR OTHER HIGH-LOAD/HIGH-FRICTION PARTS THAT ARE IN "MESH" WITH OTHER PARTS BECAUSE "GRADING" IT BY "TENSILE STRENGTH" AS IS SHOWN IN THE VIDEO ONLY TELLS YOU THAT THE METAL RESISTS "STRETCHING" PROPERLY AND DOESN'T PROVE ANYTHING ABOUT HOW IT PERFORMS UNDER "PRESSURE" BEING "COMPRESSED". AND SINCE THERE ARE OTHER METALS BESIDES "IRON" IN "STEEL" AND MANY OF THEM HAVE "HIGHER TENSILE STRENGTH" AND ARE "HARDER" THAN IRON, IF YOU GO BY "TENSILE STRENGTH" AND "HARDNESS" ALONE YOU CAN END UP WITH METAL THAT "EXCEEDS SPECIFICATIONS" BUT IS DESTINED TO FAIL IN SERVICE WHERE "TENSILE STRENGTH" AND "HARDNESS" OVER AND ABOVE THE "SPECIFICATION" ARE A VERY, VERY BAD THING. The ONLY way to know what's in "high speed steel" for powertrain parts and other parts that lives literally depend on is to "MIX" it from "SCRATCH" SINCE YOU CAN'T "UN-MIX" METALS WHEN "REMELTING" THEM. Its also IMPOSSIBLE to "melt" ANY metal in a "vacuum" since as the metal "melts" the "contaminants" in it with a melting/boiling point LOWER than its melting point will "boil off" and vaporize and you no longer HAVE a "vacuum". Nor do you WANT ONE since "air pockets" in a "casting" aren't "air pockets" at all but are "vacuum pockets" once the casting cools. And "hydrogen inclusions" and "nitrogen pockets" and other "casting defects" once though to occur during "casting" USUALLY OCCUR DURING COOLING BECAUSE OF THOSE "VACUUM POCKET" DRAWING IN "AIR" AND WATER VAPOR AND BEING HOT ENOUGH TO "DISSOCIATE" THE HYDROGEN AND OXYGEN IN THE WATER VAPOR. THEN WHEN ONE HYDROGEN MOLECULE AND ONE OXYGEN MOLECULE "BURN" TOGETHER THERE IS A SINGLE HYDROGEN MOLECULE LEFT TO GET DRAWN INTO THOSE "VACUUMS". NITROGEN CAN DO THE SAME THING BEING AN INERT GAS AND MAKING UP SO MUCH OF OUR ATMOSPHERE. BUT WHEN METAL IS ACTUALLY COMPLETELY "MELTED" WHEN CAST IT WON'T FORM "POCKETS" AND IS VERY DENSE AND INCREASES IN DENSITY IF ALLOWED TO "AIR COOL" NORMALLY. "AIR-COOLING" USING "COMPRESSED AIR" IS WHAT CREATES THOSE "POCKETS" AS AIR/WATER VAPOR ARE "INJECTED" INTO THE CAST PART OR BILLET. ESPECIALLY WHEN "HEAT TREATING" AND JUST HEATING TO IT'S PLASTIC TRANSITION TEMPERATURE (A DULL CHERRY RED FOR STEEL) WHERE ITS MOST "POROUS" AND "LEAST DENSE". THAT'S WHY SMART "METALLURGISTS" HEAT-TREAT AND "QUENCH" WITH WATER OR OIL IN A "NON-AEROBIC" AIR-FREE LIQUID AND "QUENCHING" WITH "AIR" IS AN OBSOLETE AND HORRIBLE WAY TO PRODUCE ANY "CASTING" THAT'S A "BLANK" OR "BILLET" PARTS WILL BE MACHINED FROM. It IS done as a way to "cheaply" and "cleanly" and "safely" quench castings/blanks/billets by "manufacturers" and "suppliers" ALSO trying to "save money" by producing "near-net castings" that are the "rough" shape of the "finished part" because it allows a rapid enough "quenching" to produce a "heat treated" part of the proper "surface hardness" without having "dimensions" change to the point the part has to be made larger to "distort" and still have enough metal in the right places. But you don't make high-load, high-quality parts/billets/blanks CORRECTLY and SAFELY FOR THE "CONSUMER" BY "SAVING MONEY" DURING MANUFACTURING AND YOU DAMNED SURE DON'T WANT A "HARD" PART ON THE SURFACE AND A BUNCH OF "STRESS" CAST INTO AND "TRAPPED" INSIDE A PART/CASTING/BILLET/BLANK BY A "NEAR-NET" PROCESS AND "AIR QUENCHING" ALL DONE TO HAVE A "MAX-NET PROFIT MARGIN" IF YOU WANT TO NOT GET BANKRUPTED/SUED/JAILED FOR MAKING SHITTY, CHEAP PARTS FOR EXPENSIVE, COMPLEX MACHINES THAT PEOPLE'S LIVES ARE DEPENDING ON.
Deeremeyer is correct in all of his comments. That explaination is one of the best written, unlike this missive , technical descriptions I have ever read. Simply excellent. Note to suppliers: listen to your engineers and technicians. Tell your bean counters to count beans and stay the hell out of the way of producing as near to perfect parts as possible.
Surprised the employees are allowed to lug what surly must be a heavy & delicate component from station to station. But OUTSTANDING PROCESS none the less. 👍😎
itu tidak asing bagiku sejak aku bayi gear setelah diserut,gigi gear lebih tinggi dari kedalaman cetakan gear dipanaskan hingga membara kemudian gear dimasukkan ke cetakan yang sesuasi dengan motif gear kemudian dipres ini bertujuan untuk mendapat lebih kerapatan besi hingga gigi gear tak mudah rontok setelah dingin gear dipoles dan dibalancing langkah terakhir dicelup kedalam cairan anti karat. SOEDIRAN, SETYAWAN TULUS RAHARJO BLORA CENTRAL JAVA INDONESIA
This gearbox has a history of catastrophic failures that have resulted in crashes. I had to chuckle while listening to all the commentary about polishing and such. Polishing a turd results in a very smooth turd.
Didn't realize it took so much to do this. Will electric motors simplify this in the future (similar to Tesla cars)? The engines would overall generic electricity to drive a large motor for the blades. It would reduce the need for large gearbox.
+CheapSushi , doubtful. Electrics in aircraft will still use gearboxes and require extreme tolerances and intense inspection. No doubt the electric motors themselves will be well-inspected just as recip engines and turbines are today. They have to, since people's lives depend on ALL aircraft powertrain parts being reliable.
I doubt that electric motors will catch on any time soon for helicopters, the battery energy density is nowhere near that of gasoline or kerosene. That being said, there have been a few successful electric airplanes for flight training and recreational flight; they only fly about an hour or so on a charge, but that's fine for training flights where you stay near the airport that you took off from. Electric motors drive the propeller directly, there's no need for a gearbox because the motor can be designed to run at the RPM required by the propeller. As for electric helis, if such a thing ever materializes, it very well may be possible to power the rotor directly without using a gearbox. A large-diameter 'pancake' motor with a high pole count would run at very low RPM and provide the torque required for the rotor, and the tail rotor could be powered with it's own smaller motor, saving the weight and driveline losses of the gearboxes and tail rotor driveshaft.
The more complicated something is the more things that can go wrong. My truck has crank up windows, not much to go wrong with them, and if the windows fail my truck will not fall thousands of feet and burn me into little pieces.
Well there we have it people. The answer to offshore personnel transfers. A truck powered by a hand cranked window mechanism. I wonder how long that would last if it was worked an average of 8-10 hours each day for several years. You can keep your S92, Super Puma and H175s, I'm getting myself on the hand cranked farm truck for my next offshore hitch. Apparently it will get me there with no issues at all.
NCLUSA "you don't good sense". A profound statement that makes absolutely no sense, straight from an inbred yank country hick who thinks that a manual window winder mechanism is comparable to a helicopter gearbox. Whatever you say Cleetus.
When you continue to type like a brain damaged hick, you will continue to be treated as such. No clue where you're getting the socialism chat from. I don't think you even know what the word means. Mind you, you do think that a window winding mechanism is comparable to an aircraft gearbox, so that says plenty about your intelligence, or lack thereof.
1:35 "Machining limitations require that all shaft bevel gears be made in two parts". Could the teeth be shaped (broached) instead? Even if you had to invent a totally new cutting process, elimination of that weld would be worth it.
@@josephastier7421 in 2012 two of these gearbox models failed at that mainshaft weld, which resulted in crashes according to the wikipedia page on the EC225. The company replaced these shafts in many units across the world, which is probably the reason for this QC video. No documented crashes because of that weld since. I guess the cost to add all this QC is less than changing the machining process
"Quality" parts and processes but yet the "test bench" is in a "test cell" with big, heavy steel doors separating it from the "factory floor" like somebody thinks or knows there could be flying parts at some point...
Is there any chance of survival if the main rotor was to seperate from a Collision of the teeth as you know 🤔 again as we know what caused the accidents before .a good solution would be to install a parachute system for it the unthinkable was to happen again .
That rotorhead is way too high up from the fuselage considering those blades don't droop very much. I bet that's a contributing factor of some of the Puma crashes. All that stress on the main gearbox housing. Puma is a death trap.
Исключение из редуктора конической передачи сильно упрощает вертолет. Когда уже сделают вертикальную турбовальную установку с простьіми планетарками.? Летать хочется и безопасно и дешево. Ролик информативньій.
Holy crap! That's one expensive gear. How many flight hours do you get before the tranny gets swapped out, assuming no chip lights or anything like that?
You mean Europe, the region with the lowest aviation fatality statistics on earth? Fact: the 28 countries that make up the European Union have the world's lowest rate of fatal accidents, at 1.8 per million commercial flights-CNN
+staslig Redo the hole Gearbox/Shaft. Airbus: FIX IT, OR TRASH IT, -FOR FUCKS SAKE..! How manny more shall you kill ? I hope Norway bans this shite FOREVER ! ExEMTNor
+400 CC you obviously havent read the reports coming out from the investigation. the latest news is that the gearbox was involved in an car accident while being transported from Airbus. possible fatigue fracture. nothing to do with the design
the overwhelming majority of rotary wing crashes stems from operator error and bad maintenance. It is quite rare that a properly manufactured, maintained and operated craft crashes. safety statistics per flight hour for rotary wing craft may not be as good as passenger airlines, but they are still far better than roadbound vehicular traffic.
@@joeystar8888 sikorsky shoots their shippimg containers with a howitzer cannon then drops it from 30000 ft from an airplane then NDT's the intire thing no damage. Buy Sikorsky
I'm no aircraft engineer, but that looks a flimsy part for such a critical component, I was expecting to see something more substantial for the size of aircraft, and making it in 2 parts and welding it seems ludicrous.
In a (fixed wing) plane at least the pilot has a chance to glide back to Earth, but in these machines when the engine fails (or gear box, or any other complicated parts) the machine just falls to the ground. I would never bet my life on one of these things.
Nhìn trực thăng châu âu và Mỹ thấy thèm nhểu nước dãi : kiểu dáng hiện đại , cân đối... nhìn trực thăng của nga THẤY MUỐN ...ÓI :NẶNG NỀ , KIỂU DÁNG CỔ LỖ , KHÔNG CÂN ĐỐI --- ĐẦU CAO ĐÍT THẤP ( MI.8 , MI.17 ...)
Any thoughs on how a EC225 could lose the rotor and crash and killing 13 people? Se video of rotor falling through the sky (norwegian): www.tv2.no/v/1039640/
The transmission assembly had several issues, not just one. Metallurgical fatigue of planetary gears, poor assembly discipline (the main gear was dropped and was not logged or inspected), poor maintenance discipline. This comedy of errors led to the incident. Improvements on all aspects of manufacturing, quality control during transport and assembly, impounding and investigation of suspect parts that were involved in impact type accidents, increased maintenance checks of the transmission and overhaul procedures of aged components.
Yeah I'm no engineer either, but I always thought that the whole shaft through the hub was solid right way through not hollow like that. Then the hub is just sleeved into a fitting in the gearbox is it?? Looks flimsy to me or such a large helicopter!
+Mel D Hi Mel, it depends on what duty the part is carrying out on how thick it needs to be. At 0:29 you can see what it does. All the torque and stress gets put through the bevel gear at the top, and the rest of the part only supports the gear and provides drive for small oil pumps. In aviation you are always trying to save weight, so you only reinforce the most highly stressed parts. However, the rest of the video explains that the supporting section and bevel gear are welded together (chosen because its lighter), and this weld is very close to the highly stressed bevel gear. All the failures have been around that weld. Welds tend to be weaker than the parent metal and this is where you would expect a fatigue failure of this sort. If the metal was thicker you would still need to attach the two parts, and would ultimately only delay a failure, so long as the vulnerable weld exists. In the L2 revision, they did thicken the section around the weld. Its not yet clear if this is what failed this time, and it may not be (see below) Without the weld its possible the failure would not occur. A fundamental redesign may be needed, a "design for manufacture" that eliminates the need for two parts. That is true for the previous failures that only disabled the oil pumps but left power intact. In this new failure, the whole rotor has come off, which suggests a failure of another part of the gear or other part entirely
@@Mirandorl A proper weld is usually stronger than the base metal. It's the heat affected zone that usually fails. This is why welding technology always strives to minimize the size of the heat affected zone by increasing the power density (can't think of how to phrase it better) of the process and minimizing the time the workpiece is being heated. From gas torch to electric arc to laser beam to electron beam.
It's the only way to produce it. The video shows why--the main gear and hub extension together don't allow clearance for necessary machining operations. This is how it's done, and it has always been done this way for vital reasons. Nuclear reactors have critical components welded together as well. So does your car :)
@+Devil's Offspring: True, but in either case your life wouldn't come in danger within the minute. A car you can stop, a nuclear reactor will take minutes to hours to overheat and there are backups (that should be working).
You would not believe something so big could be built with such precision, I worked in a factory that supplied aeronautical components ,the attention to detail is phenomenal ,the thought of one months work at a cost of millions not passing final inspection and end up being scrapped concentrates the mind.The manufacturing engineers and assembly mechanics are not your average Joes
Yeah, there is a good reason why manufacturing for this particular gear is explained. That weld is messed up properly.
10 May 2012: G-REDW, an EC225 LP, carried out a controlled ditching following indications of a failure of the main gearbox (MGB) lubrication system and a subsequent failure indication warning on the emergency lubrication system. An investigation by the Air Accidents Investigation Branch (AAIB) identified a 360° circumferential crack in the bevel gear vertical shaft in the main gearbox, in the vicinity of a manufacturing weld, causing disengagement of the drive to both mechanical oil pumps.[70]
22 October 2012: G-CHCN, an EC225 LP of CHC Scotia, ditched in the North Sea 32 miles south west of Shetland whilst en route from Aberdeen to the West Phoenix drilling rig. All 19 on board were rescued. A special bulletin issued by the Air Accidents Investigation Branch (AAIB) said the main and standby oil pumps were not working; a 360-degree crack found on the bevel gear vertical shaft of the gearbox had prevented the oil pump gears from being driven. A worldwide grounding of the type was initiated in response.[35] In both of the 2012 incidents, although the main gearbox lubrication system had failed, the backup system was working correctly but displaying an erroneous warning light, due to an incorrect specification of a pressure switch, which led to the helicopters being ditched.[71]
29 April 2016: LN-OJF, an EC225 LP of CHC Helikopter Service, crashed at an islet near Turøy in the Bergen archipelago, en route to Bergen Airport, Flesland, from the Gullfaks B platform in the North Sea. The helicopter was carrying 11 passengers and 2 crew members; there were no survivors. Eyewitnesses reported that the main rotor separated from the hull immediately before the crash. Due to the crash, all commercial flights by EC225 helicopters, excluding search and rescue flights, were grounded by both Norwegian and British civil aviation authorities.[72][73][74]
The one in 2016 was due to a bearing defect inside one of the planet gears. Not the bevel gear weld. th-cam.com/video/zPX7NJe1Mog/w-d-xo.html
2018/7/17 korean marine helicopter (MUH-1, surion variant, developed by airbus helicopters, used same gearbox with super puma)
crashed due to gearbox problem.
maker of this gear, "Aubert ＆ Duval" admitted they did wrong about cooling processes of the gear. it had to be air cooled, but they used water which made strength degradation.
Aren't the Super Puma gears made by gearbox manufacturer Schaeffler USA?
yep, and I loved AH presentation on EASA Rotorcraft symposium couple of years ago. To protect you from our MGB problems we will forbid you to repare it any where else but AH fascilities and TBO and other maintenance periods will make shorter... much shorter. We love our customers=)
@Stanley Banks it is okay because it cools down faster that makes production cheaper instead of letting it sit
Beautiful engineering! My wife might disagree but I would love one as a centrepiece on my table if it was not such a waste of engineering.
I wonder if it's possible to buy a rejected one ? Might have "not for flight" engraved on it, but it might also be cheaper.
You are gay and should be ashamed of yourself.
@@TheNefastor Nope. Non conforming parts must be destroyed or otherwise made completely inoperable.
@@elanjacobs1 makes sense... too many crooks would definitely try to install it on a helicopter. That's why we can't have nice things.
This is beyond just engineering.....its art
It actually impressed to think of that the gear set is made to reduce the speed and increase the torque coming from the engines and yet the rotor spins like crazy at speed.
Neat Vid.
Probably need more of this to get our confidence back in these models.
Thank you for video.
Cool accuracy on such radius.
The guy doing the final inspection is an interesting step in the overall process.
😄
"Non-destructive testing" is what you do to ensure that "production" parts are made "correctly" when "finished" AFTER developing the "manufacturing process" using DESTRUCTIVE TESTING OF "PROTOTYPE PARTS" and even then you still keep DESTRUCTIVELY "TESTING" PRODUCTION PARTS TO MAKE SURE "FAMILIARITY" HASN'T TURNED INTO "COMPLACENCY".
2:20
I bet that that operator hates his desk with a passion, as it’s angle makes the keyboard and mouse slide down.
This is a true material technology I am a technician and I like to see this manufacturing
Thank the engineers back in the 40's with slide rules and sand casting. Absolute geniuses back in that era. Absolute gorgeous Shaft Gear. Easily $25k for that one part.
Playa you are 100% right slide rules I was a tool maker in Detroit back in the day hated running this machine it was hot dirty but
I loved the smell of the factory. Now gears are produced on CC machines I work on machines that make drugs far cry from Detroit and the auto factory
But I am at the end of my time except in Florida they are building a steel factory in Frostproof. Florida I hope they will hire a old dude like me. They are from
North Carolina and hiring and will put people to school have a good day be safe.
@@nickleggett2101 Big 3 family here too. Tool and die, etc...That machine shop smell: High sulfur cutting oils, Chlorinated solvents all that, agreed.
Pill press machinery or actual reaction vessels and stuff?..
Nothing replaces experience. The fact you type fluently and understand manual machining, you Will get your new job. Make sure to include all those attributes in your resume and willing to study.. I had the people at the career center help me with mine, was hired the next day lol.
I love all of central Fla. I miss it..
You have a great day too Nick, good luck on that dream job okay. Get out their on one of those lakes and soak up the fresh air for me too eh.. Peace
@@flaplaya got your tx Monday morning thank u for the encouraging remarks it's good to hear from a brother from the old school of machining where backlash of .020 or more was a part of the day to day grind I live about 6 miles from treasure island beach I think I will go there today. Be safe take care and have a good day.●●●●●●●.
@@nickleggett2101 Twenty thousandths worked. 20 microns nowadays is just amazing.. Treasure Island near Clearwater? That's all deep sea charters and an amazing stretch right through there... Great to see others encouraging, positive additives as well. Hope you had fun I went freshwater fishing on Ft Loudon Lake caught one stripper it was nice. Keep enjoying life.. I'm teaching that buddy how to run a 60 year old Craftsman mini lathe. Belt driven and that little thing was built well. Feed screw with all the SAE ratios and everything. Pretty neat machine.
@@flaplaya got your message this am thanks Yes treasure island is about 15 minutes. From Clearwater beach but beach is to small and new large hotels put more people in a high tourist area, it's a hot spot for spring breakers. Now on this cool old lathe have fun surprised the motor still runs but things were made to last back in those days, old finds like that one could bring the owner some quick cash just keep her oiled and do not use air hose to blow off the chips it could jam the carriage and drive screws . Have some fun. Good day.
The gearbox is the weak link in a helicopter. Always has been lubrication of the system is vital. Rotation and identity numbers on the components within the gearbox should be part of the service history.
Magnifique élaboration. J'adore.
We did a lot of EB (electron beam) welding of rocket motor casings (high strength 4135 steel) back in the late 1980’s at Goodyear Aerospace in Akron, Ohio. That EB weld on the ring gear did NOT look very robust to me.
I love how the comments are always full of "experts."
@@JimLem To be fair, videos of this kind will tend to draw one of two types of people, random curious people and people who're familiar with the processes involved who want to see how it is done in other settings.
@@jimmydesouza4375 I agree, but I'm not sure how that relates to my comment. Eurocopter (or Airbus Helicopters as they're now known) is a very well established aerospace brand which has been around for decades. They spend billions on research and development. Yet one self-proclaimed expert viewing a poor quality video clip thinks they have it all wrong.
@@JimLem I work for the largest insulation manufacturer in the world, that has been around since the 17th century, that has been making fiberglass since the 1920's. The factory where I work bursts into flames due to improper process at least 20 times a year and we get approximately 4% of our shipped output returned due to flaws that are not detected.
Of course, we don't have the same QA standards as an airbus factory, but just because something is established and spends billions doesn't mean there can't be flaws.
@@jimmydesouza4375 I didn't say that either. I simply stated that it's absurd to think you can provide a professional opinion on something you've seen in a poor quality video clip.
Your example with two factory fires a month isn't the same thing. Most businesses would investigate what went wrong the first time, then implement steps and processes to minimise the risk of it happening again. If you know procedures are not being followed, yet nothing is being done to correct that, that's just blatant irresponsibility.
I'm pretty sure Airbus don't employ a "It's fine, it'll do" attitude. Failures occur. They make improvements to minimise repeated failures.
I was on one of these choppers when the bevel gear failed and it ditched in the North Sea (g-chcn) the part has now been redesigned but only time will tell if it works.
mechanical engineering brilliant I love this sort of stuff
My confidence in helicopter engines is boosted!!
The Hughes Helicopter and Enstrom has one of same dimensions as this showed in video , the gears of the Hughes is manufactured per great company General Eletric in USA.
Great work and great video...l love it thanks for posting...
La Ingenieria Mecanica una vez mas llevada al maximo...hermosas Maquinas...lo dice un Ing.Mec.
Although many of these parts looks similar to automotive parts, the cost is about 10-20x higher, as well as its durability.
Феноменальный завод, феноменальное производство!
BOMTOGL. Unimpressive tensile test at 49sec. The test specimen necking outside the extensometer test zone. Tensile tests are usually only considered valid if the break is in the middle third of the test zone between the extensometer points. Broke Outside Middle Third Of Gauge Length. BOMTOGLE.
geez! thazts crazy. I never realized how much went into making and checking thoes
+Kris Kahle and still they are killing people
Look at how small it is for the amount of torque it handles.
This vertical bevel gear shaft was redesigned after 2 accidents in 2012 and replacements should start medio 2014. Today a terrible accident in Norway with an EC225 (LN-OJF) heading home from an offshore rig. 13persons killed.. (: R.I.P. I indeed hope the new modified part was onboard.
+trollkremvideo www.verticalmag.com/features/features_article/EASAcertifiesredesignedEC225gearshaft
+trollkremvideo Heat Affected Zone ?Fatigue
+trollkremvideo the gearbox and rotor was changed this year and had 1300 flight hours.
+staslig Still a question for the changed rotor; Heat Affected Zone ?Fatigue
trollkremvideo I have no idea.
My money is on a total gearbox failure due to loss of oil, but that is just speculation at this point.
Nice video I'm very happy
nice video , good luck ! from Mongolia.
Can the electron beam welding process be substituted with friction welding (in this instance?).
That's not a "two-piece gear" unless they're "friction welding" the "pieces" together post-machining of the "ring gear". If those "genius" engineers would simply use a "bolt-on" ring gear and carrier and treat that rotor gearbox like a simple "differential" ring & pinion set-up in the axle or transaxle of any and every "land vehicle" bigger/more complex than a motorcycle or "trike" built whether on tires or tracks, they wouldn't need those fancy "surface grinder" stones to "machine" gear teeth because they wouldn't have to BE that "precisely" finished and ground. When dealing with a RING AND PINION SET the "final machining" is done BY THE PARTS THEMSELVES.
They could properly "match" the ring gear and its pinion(s) before assembly and let the parts lap and "finish machine" each other BEFORE the whole gearbox is assembled and its too late to properly inspect and observe the "break-in" process. And if that "chrome plated" gear is for anything but a "cutaway display" gearbox its no wonder "Eurocopters" have so many "gearbox" failures and crashes. You don't CHROME PLATE POWERTRAIN PARTS BECAUSE CHROME PLATING "HARDENS" THE SURFACE OR RATHER ADDS A "HARDENED" SURFACE TO THE EXISTING "STEEL" AND THAT CHROME SURFACE IS FAR TOO THIN AND BRITTLE AND "RETAINS" STRESSES IN THE METAL ITS PLATED ONTO AND WILL "FRACTURE" INEVITABLY WHEN SUBJECTED TO HIGH "UNIT LOADS" AND IT ALSO DOESN'T "RETAIN" LUBRICANT PROPERLY AND WILL LET HEAT "IN" TO THE GEAR BUT WON'T LET IT BACK OUT.
And if they have to "vacuum remelt" the "steel" before making their "blanks" they're using RECYCLED "steel" and that is EPIC STUPIDITY AND ENGINEERING IDIOCY AT ITS FINEST. USING "RECYCLED" STEEL FOR "CAST IRON" CASTINGS AND "LOW-LOAD" PARTS IS ONE THING. AND EVEN THEN IT NEEDS TO BE VERY PRECISELY "MIXED" TO PRODUCE "NODULAR IRON" OF THE PROPER "TYPE". BUT YOU NEVER "RECYCLE" STEEL/IRON FOR SOMETHING LIKE GEARS OR OTHER HIGH-LOAD/HIGH-FRICTION PARTS THAT ARE IN "MESH" WITH OTHER PARTS BECAUSE "GRADING" IT BY "TENSILE STRENGTH" AS IS SHOWN IN THE VIDEO ONLY TELLS YOU THAT THE METAL RESISTS "STRETCHING" PROPERLY AND DOESN'T PROVE ANYTHING ABOUT HOW IT PERFORMS UNDER "PRESSURE" BEING "COMPRESSED". AND SINCE THERE ARE OTHER METALS BESIDES "IRON" IN "STEEL" AND MANY OF THEM HAVE "HIGHER TENSILE STRENGTH" AND ARE "HARDER" THAN IRON, IF YOU GO BY "TENSILE STRENGTH" AND "HARDNESS" ALONE YOU CAN END UP WITH METAL THAT "EXCEEDS SPECIFICATIONS" BUT IS DESTINED TO FAIL IN SERVICE WHERE "TENSILE STRENGTH" AND "HARDNESS" OVER AND ABOVE THE "SPECIFICATION" ARE A VERY, VERY BAD THING.
The ONLY way to know what's in "high speed steel" for powertrain parts and other parts that lives literally depend on is to "MIX" it from "SCRATCH" SINCE YOU CAN'T "UN-MIX" METALS WHEN "REMELTING" THEM. Its also IMPOSSIBLE to "melt" ANY metal in a "vacuum" since as the metal "melts" the "contaminants" in it with a melting/boiling point LOWER than its melting point will "boil off" and vaporize and you no longer HAVE a "vacuum". Nor do you WANT ONE since "air pockets" in a "casting" aren't "air pockets" at all but are "vacuum pockets" once the casting cools. And "hydrogen inclusions" and "nitrogen pockets" and other "casting defects" once though to occur during "casting" USUALLY OCCUR DURING COOLING BECAUSE OF THOSE "VACUUM POCKET" DRAWING IN "AIR" AND WATER VAPOR AND BEING HOT ENOUGH TO "DISSOCIATE" THE HYDROGEN AND OXYGEN IN THE WATER VAPOR. THEN WHEN ONE HYDROGEN MOLECULE AND ONE OXYGEN MOLECULE "BURN" TOGETHER THERE IS A SINGLE HYDROGEN MOLECULE LEFT TO GET DRAWN INTO THOSE "VACUUMS".
NITROGEN CAN DO THE SAME THING BEING AN INERT GAS AND MAKING UP SO MUCH OF OUR ATMOSPHERE. BUT WHEN METAL IS ACTUALLY COMPLETELY "MELTED" WHEN CAST IT WON'T FORM "POCKETS" AND IS VERY DENSE AND INCREASES IN DENSITY IF ALLOWED TO "AIR COOL" NORMALLY. "AIR-COOLING" USING "COMPRESSED AIR" IS WHAT CREATES THOSE "POCKETS" AS AIR/WATER VAPOR ARE "INJECTED" INTO THE CAST PART OR BILLET. ESPECIALLY WHEN "HEAT TREATING" AND JUST HEATING TO IT'S PLASTIC TRANSITION TEMPERATURE (A DULL CHERRY RED FOR STEEL) WHERE ITS MOST "POROUS" AND "LEAST DENSE". THAT'S WHY SMART "METALLURGISTS" HEAT-TREAT AND "QUENCH" WITH WATER OR OIL IN A "NON-AEROBIC" AIR-FREE LIQUID AND "QUENCHING" WITH "AIR" IS AN OBSOLETE AND HORRIBLE WAY TO PRODUCE ANY "CASTING" THAT'S A "BLANK" OR "BILLET" PARTS WILL BE MACHINED FROM.
It IS done as a way to "cheaply" and "cleanly" and "safely" quench castings/blanks/billets by "manufacturers" and "suppliers" ALSO trying to "save money" by producing "near-net castings" that are the "rough" shape of the "finished part" because it allows a rapid enough "quenching" to produce a "heat treated" part of the proper "surface hardness" without having "dimensions" change to the point the part has to be made larger to "distort" and still have enough metal in the right places. But you don't make high-load, high-quality parts/billets/blanks CORRECTLY and SAFELY FOR THE "CONSUMER" BY "SAVING MONEY" DURING MANUFACTURING AND YOU DAMNED SURE DON'T WANT A "HARD" PART ON THE SURFACE AND A BUNCH OF "STRESS" CAST INTO AND "TRAPPED" INSIDE A PART/CASTING/BILLET/BLANK BY A "NEAR-NET" PROCESS AND "AIR QUENCHING" ALL DONE TO HAVE A "MAX-NET PROFIT MARGIN" IF YOU WANT TO NOT GET BANKRUPTED/SUED/JAILED FOR MAKING SHITTY, CHEAP PARTS FOR EXPENSIVE, COMPLEX MACHINES THAT PEOPLE'S LIVES ARE DEPENDING ON.
You should apply for eurocopter ...its hiring...
Deeremeyer is correct in all of his comments. That explaination is one of the best written, unlike this missive , technical descriptions I have ever read. Simply excellent.
Note to suppliers: listen to your engineers and technicians. Tell your bean counters to count beans and stay the hell out of the way of producing as near to perfect parts as possible.
...and: where have you been before? :D:D
Truly Art !!
This part is more critical than the engine(s).
Total engine failure is manageable but if this part fails, you fall like a rock.
☠BLACK BARON☠ I recommend ... hardened steel high quality pinion gears for RC helicopters as well. 1:26
This helicopter is grounded forever today.
de la haute précision!!!!pas unseulcoup de lime manuelle !!!!!!!
In Vietnam they're still rotating :))
@black zebra www.change.org/p/civil-aviation-authority-remove-the-airbus-225-super-puma-from-service?recruiter=305505445
I remember when I worked for Alcoa we had a lot control so that the price is expensive
@black zebra :))
Very interesting sir!
Showing gear case assembly of heavy engineering on display picture.
And showing Video about vertical bevel.
i'm glad someone noticed that this video is about something completely different than the thumbnail
Surprised the employees are allowed to lug what surly must be a heavy & delicate component from station to station. But OUTSTANDING PROCESS none the less.
👍😎
Betcha there was some things not photo worthy.
Great video.
itu tidak asing bagiku sejak aku bayi
gear setelah diserut,gigi gear lebih tinggi dari kedalaman cetakan
gear dipanaskan hingga membara kemudian gear dimasukkan ke cetakan yang sesuasi dengan motif gear kemudian dipres ini bertujuan untuk mendapat lebih kerapatan besi hingga gigi gear tak mudah rontok
setelah dingin gear dipoles dan dibalancing langkah terakhir dicelup kedalam cairan anti karat.
SOEDIRAN, SETYAWAN TULUS RAHARJO
BLORA CENTRAL JAVA INDONESIA
This gearbox has a history of catastrophic failures that have resulted in crashes. I had to chuckle while listening to all the commentary about polishing and such. Polishing a turd results in a very smooth turd.
What a masterpiece 🔥🔥🔥😍😍
Mesmo com este rigor de controle de qualidade a natureza ainda desafia a tecnologia humana.
Richtig geil alda! Sehr wild
I'm surprised they don't rotary friction weld the parts.
How I wish my country owned such a factory
Культура производства у арабов слишком низкая.
Не дано на текущем историческом этапе!
Sadly low IQ culture, won’t evolve until it leaves Islam behind
Didn't realize it took so much to do this. Will electric motors simplify this in the future (similar to Tesla cars)? The engines would overall generic electricity to drive a large motor for the blades. It would reduce the need for large gearbox.
+CheapSushi , doubtful. Electrics in aircraft will still use gearboxes and require extreme tolerances and intense inspection. No doubt the electric motors themselves will be well-inspected just as recip engines and turbines are today. They have to, since people's lives depend on ALL aircraft powertrain parts being reliable.
I doubt that electric motors will catch on any time soon for helicopters, the battery energy density is nowhere near that of gasoline or kerosene.
That being said, there have been a few successful electric airplanes for flight training and recreational flight; they only fly about an hour or so on a charge, but that's fine for training flights where you stay near the airport that you took off from. Electric motors drive the propeller directly, there's no need for a gearbox because the motor can be designed to run at the RPM required by the propeller.
As for electric helis, if such a thing ever materializes, it very well may be possible to power the rotor directly without using a gearbox. A large-diameter 'pancake' motor with a high pole count would run at very low RPM and provide the torque required for the rotor, and the tail rotor could be powered with it's own smaller motor, saving the weight and driveline losses of the gearboxes and tail rotor driveshaft.
Мне кажется эту деталь стоило немного надфилем поправить,видел небольшой заусенчик)))Да...такие технологии, да на автоваз!
Very lucky persons in that factory
MARAVILLOSO ... SUPER INTERESANTE ...!!
The more complicated something is the more things that can go wrong. My truck has crank up windows, not much to go wrong with them, and if the windows fail my truck will not fall thousands of feet and burn me into little pieces.
Well there we have it people. The answer to offshore personnel transfers. A truck powered by a hand cranked window mechanism. I wonder how long that would last if it was worked an average of 8-10 hours each day for several years. You can keep your S92, Super Puma and H175s, I'm getting myself on the hand cranked farm truck for my next offshore hitch. Apparently it will get me there with no issues at all.
Do you live in a hut in some shit hole country Sport?, you don't good sense!.
NCLUSA "you don't good sense". A profound statement that makes absolutely no sense, straight from an inbred yank country hick who thinks that a manual window winder mechanism is comparable to a helicopter gearbox.
Whatever you say Cleetus.
Keep making fun of Farmers Sport, you're making a lot of friends here ( : . How's that Socialism working for you?.
When you continue to type like a brain damaged hick, you will continue to be treated as such. No clue where you're getting the socialism chat from. I don't think you even know what the word means. Mind you, you do think that a window winding mechanism is comparable to an aircraft gearbox, so that says plenty about your intelligence, or lack thereof.
Nice but all without handgloves to provide rust?
very good work
Great Video, however there are other issues re the safe flight of helicopters going offshore in bad weather that needs addressing
Aren't the Super Puma gears made by gearbox manufacturer Schaeffler USA?
1:35 "Machining limitations require that all shaft bevel gears be made in two parts". Could the teeth be shaped (broached) instead? Even if you had to invent a totally new cutting process, elimination of that weld would be worth it.
Does it ever break at that weld ?.
@@TheSRBgamer63 I don't know. But I would do whatever was possible to eliminate it anyway.
@@josephastier7421 in 2012 two of these gearbox models failed at that mainshaft weld, which resulted in crashes according to the wikipedia page on the EC225. The company replaced these shafts in many units across the world, which is probably the reason for this QC video. No documented crashes because of that weld since. I guess the cost to add all this QC is less than changing the machining process
it's beautiful!!!
Anyone see how thick those test cell doors were?
"Quality" parts and processes but yet the "test bench" is in a "test cell" with big, heavy steel doors separating it from the "factory floor" like somebody thinks or knows there could be flying parts at some point...
Awesome Cool Video
Good Video 👌
Is there any chance of survival if the main rotor was to seperate from a Collision of the teeth as you know 🤔 again as we know what caused the accidents before .a good solution would be to install a parachute system for it the unthinkable was to happen again .
very good
Elecon engineering co.ltd
Anand gujarat india.
Manufacturing such world class spiral bevel wheel and pinion.
They case harden with hair lice egg shells? Novel! Is that better than the nitrogen everyone else uses?
i ride the super puma everyday at work offshore ! great helicopter ! even like it more than the sircorsky s92 !
....Said no offshore worker ever.
That rotorhead is way too high up from the fuselage considering those blades don't droop very much. I bet that's a contributing factor of some of the Puma crashes. All that stress on the main gearbox housing. Puma is a death trap.
Исключение из редуктора конической передачи сильно упрощает вертолет. Когда уже сделают вертикальную турбовальную установку с простьіми планетарками.? Летать хочется и безопасно и дешево. Ролик информативньій.
Entiendo por que son carísimos los helicópteros. Además puro guey verg trab ahí!!
Holy crap! That's one expensive gear. How many flight hours do you get before the tranny gets swapped out, assuming no chip lights or anything like that?
+spaight711 2000h+10% margin. Sometimes you get to extend this another 10 %
In what situation is a "life-limited" part allowed a "10% margin" let along "another 10%"? Oh wait. We're talking about Europe. Never mind.
You mean Europe, the region with the lowest aviation fatality statistics on earth? Fact: the 28 countries that make up the European Union have the world's lowest rate of fatal accidents, at 1.8 per million commercial flights-CNN
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#$
I thought Nitriding was pronounced 'Nightriding'
It's a dead giveaway that the narrator has no idea what these various manufacturing processes are and why they are used.
Helicopters are awesome and I love them for the amount of precision and quality but at the same time they scare the sh*t out of me.
and still these things keep dropping from the sky.
+staslig
Redo the hole Gearbox/Shaft. Airbus: FIX IT, OR TRASH IT, -FOR FUCKS SAKE..!
How manny more shall you kill ? I hope Norway bans this shite FOREVER !
ExEMTNor
+400 CC you obviously havent read the reports coming out from the investigation. the latest news is that the gearbox was involved in an car accident while being transported from Airbus. possible fatigue fracture. nothing to do with the design
the overwhelming majority of rotary wing crashes stems from operator error and bad maintenance. It is quite rare that a properly manufactured, maintained and operated craft crashes. safety statistics per flight hour for rotary wing craft may not be as good as passenger airlines, but they are still far better than roadbound vehicular traffic.
Vanklow what ever fuck head
@@joeystar8888 sikorsky shoots their shippimg containers with a howitzer cannon then drops it from 30000 ft from an airplane then NDT's the intire thing no damage. Buy Sikorsky
I'm no aircraft engineer, but that looks a flimsy part for such a critical component, I was expecting to see something more substantial for the size of aircraft, and making it in 2 parts and welding it seems ludicrous.
Looks alot like the ring and pinon out of a Dana 60 .
In a (fixed wing) plane at least the pilot has a chance to glide back to Earth, but in these machines when the engine fails (or gear box, or any other complicated parts) the machine just falls to the ground. I would never bet my life on one of these things.
helicopters can land safely without engine power, its a maneuver called auto rotation
@@TheNinjaRichie Only if a gearbox is still working.
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I assume this is the way the ones that are failing are made. This doesn't offer a cause or solution to the problem.
Why not doing hardness direct nitriding is nothing suitable for good result
Isn’t that a CVT transmission from a Nissan?
And the lubrication of gears?
Oh yeah wait they forgot that!
But also if you dont shut up im gonna lubricate your gears! (Just kidding i just wanted to say that)
Any thoughs on how a EC225 could lose the rotor and crash and killing 13 people?
Se video of rotor falling through the sky (norwegian): www.tv2.no/v/1039640/
The transmission assembly had several issues, not just one. Metallurgical fatigue of planetary gears, poor assembly discipline (the main gear was dropped and was not logged or inspected), poor maintenance discipline.
This comedy of errors led to the incident.
Improvements on all aspects of manufacturing, quality control during transport and assembly, impounding and investigation of suspect parts that were involved in impact type accidents, increased maintenance checks of the transmission and overhaul procedures of aged components.
"neetriding"... oh come on, you couldn't get an engineer to tell you how to pronounce this stuff ? :-D
Yeah I'm no engineer either, but I always thought that the whole shaft through the hub was solid right way through not hollow like that. Then the hub is just sleeved into a fitting in the gearbox is it?? Looks flimsy to me or such a large helicopter!
+Mel D Hi Mel, it depends on what duty the part is carrying out on how thick it needs to be. At 0:29 you can see what it does. All the torque and stress gets put through the bevel gear at the top, and the rest of the part only supports the gear and provides drive for small oil pumps. In aviation you are always trying to save weight, so you only reinforce the most highly stressed parts.
However, the rest of the video explains that the supporting section and bevel gear are welded together (chosen because its lighter), and this weld is very close to the highly stressed bevel gear. All the failures have been around that weld. Welds tend to be weaker than the parent metal and this is where you would expect a fatigue failure of this sort. If the metal was thicker you would still need to attach the two parts, and would ultimately only delay a failure, so long as the vulnerable weld exists. In the L2 revision, they did thicken the section around the weld. Its not yet clear if this is what failed this time, and it may not be (see below)
Without the weld its possible the failure would not occur. A fundamental redesign may be needed, a "design for manufacture" that eliminates the need for two parts. That is true for the previous failures that only disabled the oil pumps but left power intact. In this new failure, the whole rotor has come off, which suggests a failure of another part of the gear or other part entirely
@@Mirandorl A proper weld is usually stronger than the base metal. It's the heat affected zone that usually fails. This is why welding technology always strives to minimize the size of the heat affected zone by increasing the power density (can't think of how to phrase it better) of the process and minimizing the time the workpiece is being heated. From gas torch to electric arc to laser beam to electron beam.
ÓTIMO TRABALHO, BRASIL OK
Magnífico
AMAZING... You could say that is a fairly important piece eh ?
They must be kicking themselves for not trying harder to figure out a way to cut the cogs in that gear so it could be made in one piece.
Color me impressed :)
They just want to be shure that they are shure of being shure
You dont think the factory knows how to put in the rotor head assembly?
muito bom!
Bom trabalho pra vc fica com deus
'
very good helicoptercraft...
very well...
workers are good using clothes / dresses codes while working at the helicopter company
VERY VERY NICE BEVEL NICE
mechanical/ materials engineering by deffinition
2piece shaft showed its weakness in norway.........
It had nothing to do with the shaft. A planetary gear failed catastrophically.
So many testing done on the gear before using it in helicopter.
M whshl,? #29#;*;3//
Speuysbsa
Khnz. ,aa whshl n , z
Aa khsheyr ,mawlow
. ahjzhrk
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K snswwled
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Good perfection
A million $ gearbox?
Welding two critical components together bad idea.
should've been carbon fibre ages ago IMO
It gets to hot for such laminates inside the Gearbox. The gears themselves are still best when made from metal
@+Meddlemoe? What are you trying to say? ppl are trying to say that the whole thing should be machined from a complete thing and not welded..
It's the only way to produce it. The video shows why--the main gear and hub extension together don't allow clearance for necessary machining operations. This is how it's done, and it has always been done this way for vital reasons.
Nuclear reactors have critical components welded together as well. So does your car :)
@+Devil's Offspring: True, but in either case your life wouldn't come in danger within the minute. A car you can stop, a nuclear reactor will take minutes to hours to overheat and there are backups (that should be working).