This was absolutely fantastic. You are a gifted teacher - among your many other talents. Every PT-6 pilot could learn a lot from this. I’d bet my hat on that. Thanks a lot.
Just want to say that I have been enjoying your lectures for a long time and have learned lots about the machines that keep my humble butt alive at work. You are appreciated and respected! Thank you.
hey, this talk reminds me of a helicopter monitoring system that i built for north sea operators, in 1986...recorded and checked for temperature and rpm on twin-turbine aircraft, and used a time/temp/rpm algorithm to turn on warnings for exceedences of 'caution'/alarm/'please land now!' ... thanks for showing how this well-known turbine works!
Years ago you were the very first channel ever watched because I was curious about jet engines and rediscovering you today after not seeing your channels for a couple years and I'm familiar with the Mike patey situation and it was refreshing to hear your take on it
really very clear explanation of how a PT6 engine works, and also the dangers of hot starts and sudden shut down from high power. Also a very clear reason for boroscope inspection of the hot parts of the engine. brilliant thanks.
I’m glad you have healed enough to ride to Oshkosh. Now that I’m older I find don’t photograph as many planes as I used to. I began to realize I’m missing the show by looking through the viewfinder.
I saw Mike Mike's vid and it was great to get a follow-up from and engine guy. Turbines are wonderful, and everything you stipulated about the cool down makes perfect sense.
P&W stipulates stabilization times during test as minimums in the F100 world - can be more never less i.e. 5-minute warm-up @ idle, 5-minute cool-down at idle before shutdown are two examples. Many other test points are also time-based and again minimum stabilizations
Great video and very informative. I don't fly or know anything about power plants but really enjoy learning about them. They way you presented this information gave me a greater understanding of turbine engines. I have a lot of respect for you and Mike on your expertise in your respective fields. Thanks for the video. I really enjoyed it.
Had a pt6 grenade on me, in a caravan c208. Audio of it destroying itself in the background on my mayday call on my channel. Good times. It was sulfidation corrosion on the compressor turbine locking the blade in place on the fir tree area of the disc. This stopped the oscillation in place that would normally happen and made the blade bend until it failed and cleared out the engine. The gas generator moved back 3/4’s of an inch in its mount. It actually triggered an AD that affected all engines with the same wheels.
Hi AgentJayZ, I'm pleased to hear you're recovered after your injury and that it didn't stop you getting to Oshkosh. I've taken a look at Mike Patey's video, all 42 minutes of it. He's obviously very grateful and very relieved that, with plenty of altitude, he was able to glide into an airport, rather than plough a furrow in a cornfield, or do an emergency landing on a highway (see below). However, we don't get too much of the engine itself and he does keep describing the event as an "explosion" when it was clearly an uncontained engine failure. No doubt P&W Canada(?) will be able to home in on the root cause of the failure, but it does appear to have been a power turbine stage 2 blade failure, with possibly one blade causing a 'haircut', hence all the 'shrapnel'. As the aircraft was landed safely at an airport, will the NTSB become involved? We had our own emergency landing locally at around 1800BST on Thursday. A light aircraft on short finals into Gloucestershire Airport (30 minutes north on the M5 from my home) had a suspected engine failure just a few hundred metres out and landed on the Armco in the middle of the A40 Golden Valley bypass, presumably because the road would have been really busy at that hour. Fortunately, the pilot walked away unhurt.
Nice to see back and healthy! I follow Mike Patey (Draco is probably my favorite plane EVER!) , but also enjoy your videos, and am looking forward to your insights.
Way back in the late 70s we had a J52 turbine disk disassemble itself in flight. It effectively cut the A-4s tail into pieces, penetrated the wing fuel tank, and caused the pilot to have to eject on fire and out of control. Fortunately the pilot was not hurt and it happened over ranch land so no damage or injuries on the ground. It was the first crash I was on. It was obvious what happened as soon as we saw the enjine. Everything behind T2 disk was gone. 2 turbines, their guide vanes, seals and other assorted goodies successfully and rapidly disassembled themselves in flight. This was a excellent video and description for people who donot know jets and how they work. Well done.
Love that you rode your motorcycle there. Love it! I have a FJR 1300 and that's another bike that goes thousands of miles with not many issues ever. Thanks for the video.
As a retired pilot and survivor of near 12,000 hrs as Capt of helicopters, both single and twin, I can tell you engines fail. Twice after maintenance ! Once the engineer lost a bolt whist refitting the engine intake after a 100 hr. You could see the new bolt fitted in the 12 o'clock position. A search was made and the missing bolt successfully found hiding in the corner or the engine intake. later in flight some hours later it made its way into the engine causing a failure with massive vibration. After the emergency landing another engineer found the offending bolt chewed up and back in its natural hiding place in the lowest corner of the intake. It had repeatedly bounced off the compressor blades, breaking bits off all over the place, those went through the engine. The 100 hr engineer lied about the situation, saying he never replaced the bolt. saying he never lost the bolt. yet we had the "old" bolt and the evidence of the newly fitted replacement ... Its colour was like new the others were darkened with dirt and soot. Then with other evidence and the passage of an ongoing legal dispute and 5 years later he confessed. The claim against his insurers was eventually met. Is this form of dishonesty unusual ???? No... the conflict of interest is there. Disciplinary action or a white lie ??? The second was in a single engine type. A hired helicopter, I noticed on first start it was slow to spin up and hung a bit. The engineer said it did that !! I was inexperienced at the time, and noticed it was maybe 5 seconds over the start max on first start of the day and quicker in subsequent starts. But it flew well and made the power. 2 days later, cruising at 2000 it exploded. The only word for it. Massive bang, yaw and instant lost of power auto landing and perfect short run on on smooth grass !!! Some blades had cut through the airframe and exited beyond, some had gone through the baggage compartment, some had hit the rotor blades. Did I say it went with a bang ??? I collected a handful of blades scooped out of the engine bay as souvenirs. Then the other two were in petrol types. The first the very next day after maintenance and the fitting of a new engine! Of course everyone pointed to the pilot as cause, yet the set up in my opinion lead to the waste gate not being calibrated properly meaning partial power or in my case, a restriction of air, insufficient for sustained flight. Again engineering told the truth as they knew it saying it was impossible, yet it happened and all evidence pointed to a faulty install. The next was my fault ..crop spraying an underpowered petrol heli running on minimum fuel all the time, dipping the tanks for accurate quantity reads and frequent refuels every 15 minutes, and error occured, My ground guy dipped the tank (it had two interconnected) the procedure was we only dipped one tank. I had landed in the corner of a field, it was ever so slightly out of level yet allowed the dip to be in error. The dipped tank gaining a benefit of fuel from the other slightly higher tank. Not quite on level ground gave a false dip stick reading .... at the 12 minute stage the engine stopped, whilst I was in the middle of a torque turn with a bucket close coupled below on the hook. It went quiet whilst the nose was up at 70 degrees in the turn, I saved the bucked and the helicopter and landed perfectly in the last seconds cutting loose the bucket and kicked the tail of the helicopter to one side so I did not land on it. Later as an owner of helicopters engaged in public transport flights we flew without incident for years, except I came across dishonesty more than once. Again this conflict of interest came into play, after damaging the helicopter the engineering out fit tried to cover it up, without simply saying what had happened. So in nearly 49 years I found dishonesty amongst engineers common and expensive. Their motivation to cover up being paramount.
I’ve experienced one engine failure in flight due to mechanic error, numerous issues right after a maintenance event. Some could have been serious. One time we where transferring fuel and deducted that the fuel harness was wired incorrect after the event.
Sounds like a much better time than the last time the trip was attempted. Rubber side down check. Quarantine restrictions, wtf? Keep posting. I'll keep watching.
I feel you may be spot on. I'm retired now but had worked on the PT6A series engines for many years. I started in 1980 for the Pratt & Whitney Canada Service Center Network in Burlington (Vermont) and retired in 2013. I have many fond years working on PT6 engines!
We at Orange Coast Collage got to take apart a PT-6 and an Allison-250 for the A&P program. Both are incredible designs. The Gas flow in the PT-6 is trick.
I’m proud of you for making the journey on the bike. I just sold my 1985 k100 RT with 123000 miles and it still ran great and ever leaked or burned oil. Great bike brand. Replaced it with a R1150rt with 98000miles and I love it. Keep them coming brother. I always learn from your videos.
You're supposed to borescope them every 400h or so. We borescope our -42s when we do the nozzle changes. Again, he's experimental so he doesn't have to follow the same MSA as we do on engines operating under CAR 703. Also the nomenclature we use on PT6s on aircraft is Ng and Np for the different speeds in the engine. It says in the King Air POH that you should idle the engine until ITT stabilizes for about 1:30... almost no one does it despite being written. We can tell when we do a Hot Section inspection because you can see the tip rub marks on the segments.
How involved is the boroscope inspection? Can you do it easily and routinely, or do you have to remove a ton of stuff for hours to stick your camera and look at the naughty bits?
@@nraynaud Depends greatly on the engine. Pretty much anything made in the past 60yrs had borescope plugs that makes the job easier. Getting to the plugs and getting the borescope inside where you want it can be difficult. PT6's are pretty easy.
@@mytmousemalibu I'm still thinking of Mike's airplane. If it easy, he might do it routinely without mentioning it on video because it's not a topic on his mind.
@@nraynaud It depends on how easy his cowlings are to get off. While its not that hard of a job after that, its not practical to do frequently and with failure like this, there is likely no visual indication of impending failure.
@@nraynaud on the PT6 it's fairly easy. we can remove a couple of the fuel nozzles and with a long enough borescope, go right the way around the circumference of the engine. removing the cowlings for access is usually the most annoying part.
Thx Agent Z for an informative and entertaining video. Glad to see you made it to Oshkosh EAA fly in inspite of your injuries. MP was lucky He didn't have a fire during his engine out. I like that you road your GS there. FWIW I ride also currently have RFS 525 Katoom and '14 Duc Mutley PP. I've been riding since childhood and have 3 daugters and 5 G'kids with all riders 6th one is 3yrs old but were working on it. Have ridden in So Pacific in USN and road Mex2Can off road in Y2k+1 and about 15 LA2Barstow 500m DS rides. Enjoy that GS.
It's luxury to have a teacher that know that exact engine Mike Patey use that well giving a great explanation that even I who have absolutely zero experience with jet/turbine engines could follow, and I'm confident you'll keep your cap. I'd love to watch a collaborative video with @AgentJayZ and @MikePatey where you discuss, among other things, the engine failure Mike had. I am confident it will go viral in the aviation community on TH-cam.
Another fascinating video. My plane has the Czech PT6ski turboprop, aka, the Walter 601. Very similar design as the PT6. In addition to the borescope inspection every 100hrs we also have a combustion chamber rivet check done. Like you mentioned, something coming loose in the combustion chamber can cause a domino effect in the turbines.
Thanks for the very interesting video. I had never really thought about how that engine was laid out but it looks like a clever design and you did a great job explaining it.
Nice video explaining what might have happened with Mike's Pt6 engine (I saw his video as well). It will be interresting to see the result of the investigation of the Pt6.
You're talking about Mike being a big deal, well don't put yourself down like that, you're a pretty big deal too! Very few people can do what you do. I'm sure Mike would absolutely love to talk shop with you.
Thanks for another very interesting video Sir. Equal Thanks for your respectful acknowlegment for Mikes skill & professionalism. Both of you have great descriotive information.
Mike also I believe stated that that engine was not the original engine because he removed the original and sent it to P&W because of a HOT START and the engine that (BLEW UP) was from P&W and had a total of 5 hours in Turbulence but very High time.
HA! That's almost word for word what I said too. I know he's being really nice about it, but if I bought an engine and it blew up five operating hours later I'd be having a serious conversation with the people I bought it from. I doubt he buys things from anyone "as is" and without any reasonable expectation of quality.
First time watching your vids, I like your presentation style and the way you present your info. Thanks for the great breakdown of MP’s engine failure.
I'm from Houston, Texas and 38C(100F) is hot for anybody and everybody, especially with high humidity. Houston is the most air conditioned city in the world for a reason. Anyways, it's great to hear your thoughts on Mike's issue. I always enjoy your videos! Keep 'em comin'.
I've been to Houston once, in January. It was too warm for me, but I was impressed with the size of it. My town is four minutes from the south end to the north... five in rush hour.
@@AgentJayZ Too warm in January?! That's about as cold as it gets here😂. As far as Houston's size, I love living here, but we could make it a more walkable city. If you don't have a car here, you're totally out of luck...
They're not even complex, but when you consider the operating temps and tight tolerances, they are amazing. Germany's first turbojets needed overhaul after a flight or two.
@@NotSure416 Advanced materials don't create complexity. Tolerances or temperatures don't create complexity. Engineering 101. Parts count or mechanical complexity does. A PT6 or non-variable stator turbine is way less complex than the piston powerplant in the typical GA aircraft, unless you're flying a 2 cycle engine.
Even though I assume you mean "car" engine, jet engines are much less complex. As you mentioned, some of the materials have to be esoteric with tighter tolerances, and the temp and centrifugal stresses are higher, but the fixed stator jet engine is about the simplest powerplant out there, both in theory and in practice. The ubiquity of the internal combustion 4 cycle engine just makes them seem simpler as they're more accessible. Watch one of AgentJayZ's turboshaft engine teardowns. I think he has a few associated with jetboats he crewed. If size is intimidating, YT channel Just Think has a Williams WR24-7 axial turbojet all torn down on a bench. Count the parts. It isn't a dud--he gets it running again. Or look at a few of the minis like the new Czech TJ100-series turbojet engines. The Czech engines are actually powering piloted aircraft like the Sub Sonex.
At 23:53… …also air changes at least 90 degrees at every guide vane/compressor/turbine stage as it navigates the labyrinth. It’s path definitely doesn’t go straight thru.
Just a question - Is a visual inspection really adequate to detect these cracks or is it more of the case that it is "better than nothing" if you are not going to actually tear the engine down? Does the borescope provide increased magnification to allow better detection?
1 - Visual inspection is the procedure specified by the manufacturer, providing it is performed at the required hours of service interval, and providing there have been no overtemp events. Engine teardown is done at the specified overhaul interval. 2 - Boroscopes have adjustable magnification, and adjustable...extremely bright illumination.
Been a while since I've chimed in! I do watch Mike and was hopeful you would respond Jay. I pretty much had the same conclusions. A little ironic but last month I saw a JT8D on an MD-88 let go right before my eyes. A loud bang, smoke, and a cloud of very expensive metal ejecting from the exhaust duct. We found out it lost a nozzle segment via borescope investigation. Combustors and compressor were fine. It was violent enough that the cases swelled and it blew a number of nozzle segments out into the turbines and wiped it out. I have a few souvenirs from that. Luckily it was a ground run. No fire, no injuries. Quite a thing to see. Our borescope is pretty tricked out. It can take dimensions and 3D model images. Full 360 articulating head, all the good tricks!
@@AgentJayZ You could say that! Our hangar doors were open and I like watching & listening to those old low-bypass engines make smoke & thunder. He was slowly advancing the throttles, not quite to takeoff EPR when it let go. Boom! It spooled down pretty quick and seized. Took a good long while to get the ramp cleaned up. Some of the guys had nearly full turbine blade or stator blades for souvenirs, mangled of course. That engine had just had some hot section work done on it by an outside vendor. It was more than likely a maintenance error that caused it rather than a true engine failure. Not good but quite a rare spectacle to have witnessed!
I'm not even subscribed to Mike Patey's channel but have watched some of his videos about the Turbulence. Watched the engine failure emergency video yesterday... and here I am, absolutely fascinated and glued to the screen, watching some other channel's possible failure analysis.
1:44 That was my favorite part of the video. Cheers my CanAm counterpart from way too sunny and miserably hot South Florida. I know Sun-N-Fun is a TRIP for you, but if you do make it to Lakeland I will definitely drive over. Till then my Friend.
Hello from Australia; your comments at around 20:00 regarding letting the engine cool before shutting down. As a model turbine flier, I have often been asked by other modelers why I throttle up to about 30 to 40% before shutting down; why I do this is when the data terminal is plugged in I have noticed that the EGT drops to the low 500 degrees rather than the 600 degrees at idle power setting. Am I wasting my time or does this make a difference to the longevity of the turbine? Thanks.
You are doing exactly what's best for the engine, and exactly what all the warbird jet pilots do. Shutting down from the minimum EGT places the least thermal stress on the hot parts. "Ground idle" is set to minimize thrust and fuel consumption. If you can afford the fuel and have good brakes, find min EGT, run there for a couple minutes and then shut down. Well done, sir!
@@AgentJayZ Thanks for the reply; I have already had one with a catastrophic failure of a cast compressor wheel (only 47 starts and 4.6 hours of run time), so the more that I can conserve the engines, the better. I have only been letting the temperature stabilize and then shut down, but I will keep it running longer. After shutdown, I use a battery air blower in the intake duct for a couple of minutes also. Thanks again for the reply.
Remember the EGT is showing the temp of the exhaust gases, but what you are really interested in is the temp of the metal parts in those gases. Give them time to reach the temp of the gases. I would not blow air through the engine after shutdown. That speeds up the cooling. You want the temp change to be nice and slow. After shutdown it will not heat up again unless it's on fire.
I’ve been watching you for a number of years now. With that said, I no more watched Mikes video thirty minutes before running across yours. Definitely got my attention with the subject matter. Yeah he kinda exploded the fan disk or maybe two. Peppered his airframe all over with nice coin sized holes. It’s good he was able to make it to a nearby airport and put her down safely. The one big take away I got from the event is he stressed taking safety seriously and practicing emergency procedures over and over so your well versed in piloting your way down.
AgentJayZ, glad you felt better in time to go to EAA. The heat and rain were a bit brutal this year. This video is another great perspective, one of the reasons why I have been following your channel for years. I hope you enjoy your boxer for hundreds of thousands of Km miles. We sure did ; )
Worked on CH-135 Twin Hueys with 408 Tac Hel Squadron back in the day. P&W Canada PT6 twin pack in those venerable choppers. If not mistaken its replacement the CH-146 Griffon that replaced it uses a later version of the PT6 twin pack. Robust, proven power plants. Don't hear about many failures so this is very interesting.
Great analytics of a serious subject. Anxious to hear what went catastrophically wrong with Mikes PT-6. And I agree completely with your sense of the build quality and research that went into the assembly of parts and pieces that became the world’s fastest turboprop. It’s amazing, as is the pilot. Textbook procedures culminating in a well thought out process of safely landing and zero injuries ( probably slightly elevated heart rate, but no data on that one)😂. Again, great video, and I know that he would gladly send you a cap!
At 23:37 you mentioned that you saw a compressor blade that broke off and moved upstream and the upstream compressor was taken out. Could you please say a little bit more about how it was determined that a broken downstream blade hit an upstream blade as didn’t that upstream compressor send a lot of bits all over the place (as in downstream). This is not about questioning anyone about the determination but to learn about something that probably has an interesting story. It would seem plausible that a compressor blade is loaded towards the upstream direction. This is similar to fan blade fragments being ejected out of the front of a turbofan engine upon breakage under certain conditions (the NTSB review of the Southwest flight that had a fan blade break talked about that and a 777 that had hull damage forward of the damaged engine was traced back to the titanium fan blade). I find such things that at first seem counterintuitive but on more rigorous inspection to be possible, to be fascinating.
Was a long time ago in an industrial LM1500 (J79), but one stage of compression, and all behind it, was completely gone, and the one in front of it was fine. The stage in front of that one had impact damage to the back of the blades... the shapes of the impact on the back of those blades had threads that matched a 1/4-28 bolt, which must have been the cause of the initial damage...
I went to Oshkosh. I talked to P&W at show (they know the Patey and sold them upgraded engine for their PC12). The 1st hot section turbine disk failed. Yes UT blew parts out exhaust.
I was up at Oshkosh on Friday and Saturday. Got to see the MiG-23 on static display, and watched it taxi out for take-off... and then taxi back. 😞 Saw the restored P-47 fly on Saturday, and it was gorgeous! I took pics, but there are some great youtube channels with excellent videos. I recommend AirShowStuff videos and Airailimages. The Dronescapes channel has some of the Warbirds in Review lectures/talks too, which is usually excellent.
It will be interesting to see if that indeed was the cause. The PT-6 is arguably the most reliable engines ever produced, and for it to happen to Mike is even more statistically unlikely. Am thankful he was ok.
Amazing engine and explanation of what made it blow. Thank God he didn't crash and burn so now they'll be able to ascertain what caused that engine to explode..! Oorah, Bud
Excellent explanation as to root causes of failure Agent JayZ.... I hope Mike Patey watches your video explanation of failure causes..... I am betting someone "claimed" the engine got a complete visual inspection that wasn't done properly, or, the history of the engine, being used was lost, and a couple of hot starts by the previous owner/ pilot did the damage.
There is at least one program for life extension of a pt-6 that I know of. The one I know is called MORE, which takes a 3600 tbo and moves it to 7200. For the higher time, you are required to do certain maintenance at a lower time interval, ie 300 in stead of 400 hours and more inspections of the hot section. Fed ex was the creator of the MORE program if I remember correctly.
As a Canadian passionate by aviation, IT geek/DYO mechanic/you name it, I absolutely love to watch your videos. You mentioned that you highly suggest to do a borescope inspection of the hot parts especially when buying a second hand engine. Understanding how critical this process is, should that be done by the seller and comes as an mandatory step when selling this type of engine (i.e. inspection certification)?
very good video.... me thinks you have a very valid point and I am going to say Mike did not tear that engine down far enough to prove/disprove the theory... But betting you have it nailed...
Point of information from undergraduate level metallurgy: metal doesn’t crystallize from being overheated after annealing. The grains of metal are in a lattice structure that is already a “crystalline” structure. Overheating to 0.3 to 0.5 of melting temp can cause reorganization of the crystalline grain structure usually discontinuous to where one section has a different grain structure than another section of the piece of metal. Viewing the surface of a break reveals what is clearly a crystalline structure so observers may deduce “Aha! It crystallized causing it to break.”. In a sense, but it was always crystalline.
You may not have learned the specialized stuff in school yet... like the fact that aviation gas turbine blades are usually one single crystal of metal. I was in error using that word however. The overheated blades change from having a smooth surface texture to having a surface that looks and feels like sandpaper. They seem to become more brittle, and you can often find tiny cracks in that surface. The video linked to in the description called Removing Blades shows an example of this.
I kinda wonder if the engine had a hot start at one time or another i know my engines have to be spolled up to cool them down before starting some times after a heat soak when getting fuel ? Gary K
Mike said that the prop instantly stopped in his video. I had this happen to me in a Twin Otter with PT6-21 engines. Yes it gave me warning signs. When I shut the engine down between flights I cut hear a ticking sound. Had a mechanic take a look and was told it was a tach or accessory drive making noise and it would be fine. LOL 4000 feet after takeoff next flight the prop instantly stopped, Broke all the motor mounts except 1. Turned out to be a gearbox failure. If the engine fails on a PT6 the prop should continue to spin until you feather the prop. Maybe this was his issue?
I saw his video and he clearly said the prop stopped instantly. If he didn't mean to use those words, maybe he needs to clear that up??? A prop on a PT6 does not stop instantly unless the gear box is damaged. It will free spin until you feather the prop, then it will stop. He is leading non experienced pilots down the wrong road if it didn't stop instantly. @@AgentJayZ
@@isprouse The Propeller/transmission is directly connected to the power turbine, so if the engine seizes, so would the prop. Unless it has a one way bearing like that in a helicopter.
Chippy... the PT blades broke, stuff was mangled, but I'll bet you the PT turned at least a thousand revs until it stopped moving altogether, down from 34,000 rpm to zero in a screeching, grinding end. That is not what I call instantly. You?
I actually caught a break and at least got to watch the live stream of the flights this year. We'd just gotten back from a southwestern museum tour of old warbirds, with our final stop in San Marcos to see a still-flying C47 (not a jet, but Very cool!) Speaking of iron butts, I just saw the story of the german fellow who cycled (like pedal powered) from New York to Oshkosh! Holy cow, that's a feat at any age, but this guy easily had 15 years on me! Glutton for Punishment mode engaged!
It's absolutely critical that you allow the engine to cool down before you shut it down...just like the manufacturer calls for. The PT-6 engines are extremely reliable.
Mike clearly states it in his most recent video that it was the PT2 blades gone (PT1 damaged but not gone) and that the engine while used had come from P&W.
Excellent video Agent Jay Z! Glad you made airventure 23’ wish I crossed paths with ya I was tenting with my wife in Paul’s woods campground. Very good man love your new bike. ✌️✌️
Professor JZ comes through again with his honest opinion of Mike's engine out. I'd bet my Bengal season tickets that engine had a hot start earlier in it's life rearing it's ugly head later at 30.000 feet. The forensic wrenches will find the problem and share their findings with the community. We live through the past.
Maybe you should give your opinion on the Titan DSV. Just kidding. Seems like every youtuber is capitalizing on that. I like that you're an engine tech that makes youtube videos rather than a "youtuber". Anyway, thanks for this video. Very easy to understand!
My Honda ST1100 motorcycle had 142,000 miles on it when I hit a deer around Eagleville, California back in 2003. The bike hummed like an absolute sewing machine. In addition, I didn't baby it... I flogged it mercilessly up and down the full range of the tachometer during tens of thousands of miles of Appalachian mountain twisties tip-over wing dragging. My Suzuki Bandit, the 600cc version, has over a 100k on the clock too. It's an air cooled engine that gets beat on far worse than the ST1100. It still runs like a scalded greyhound even though I've been through numerous sets of footpegs. Modern major marquee motorcycles rot more from sitting unused than constantly piling them up with mileage.
Mike Patey... An incredible experimental aircraft personality. But, like Alex Honnold, the incredible free soloist rock climber, pushing the envelope eventually breaches the envelope. Hopefully, they'll both be with us for a long long time... But, flying too close to the sun, too often, and too long has its predictable conclusion.
I like the riding position of the ST1300 so much more... but the engine of the CTX is retuned. It only makes 84 Hp, but it makes locomotive torque. If I had the time and space, I would put the CTX engine in an ST... Maybe it's just cams and the ECU...
This was absolutely fantastic. You are a gifted teacher - among your many other talents. Every PT-6 pilot could learn a lot from this. I’d bet my hat on that. Thanks a lot.
Thanks!
Every pt6 driver should download and read know your pt6 (key new owner wisdom).
I'd be surprised if Mike Patey wasn't one of your subscribers. Honestly, he should fly himself up to the great white north to visit your shop.
That would be great!
He would be an honored guest.
He’s gotta be
Sometimes I wonder how much time Mike has for TH-cam considering he is always getting back to work.
@@wild_lee_coyote yes, but how can he always be getting back to work, when he’s always working???
Just want to say that I have been enjoying your lectures for a long time and have learned lots about the machines that keep my humble butt alive at work. You are appreciated and respected! Thank you.
Thanks for the kind words!
hey, this talk reminds me of a helicopter monitoring system that i built for north sea operators, in 1986...recorded and checked for temperature and rpm on twin-turbine aircraft, and used a time/temp/rpm algorithm to turn on warnings for exceedences of 'caution'/alarm/'please land now!' ... thanks for showing how this well-known turbine works!
Years ago you were the very first channel ever watched because I was curious about jet engines and rediscovering you today after not seeing your channels for a couple years and I'm familiar with the Mike patey situation and it was refreshing to hear your take on it
Well you made that completely digestible and easy to understand. You have an educational gift (I'm sure you've heard this 1000 times).
really very clear explanation of how a PT6 engine works, and also the dangers of hot starts and sudden shut down from high power. Also a very clear reason for boroscope inspection of the hot parts of the engine. brilliant thanks.
"air turns corners better than rocks and sticks and little birds".....classic JayZ
Big Bird turns corners quite well, but the yellow feathers mess up the combustors.
Thank you for that very clear exposition of the PT-6 flow path and general arrangement. Good stuff!
This is exactly the take I wanted *while* watching Mike’s video. Thanks for breaking it down and I look forward to Mike’s response.
I’m glad you have healed enough to ride to Oshkosh. Now that I’m older I find don’t photograph as many planes as I used to. I began to realize I’m missing the show by looking through the viewfinder.
Exactly!
I saw Mike Mike's vid and it was great to get a follow-up from and engine guy. Turbines are wonderful, and everything you stipulated about the cool down makes perfect sense.
P&W stipulates stabilization times during test as minimums in the F100 world - can be more never less i.e. 5-minute warm-up @ idle, 5-minute cool-down at idle before shutdown are two examples. Many other test points are also time-based and again minimum stabilizations
Great video and very informative. I don't fly or know anything about power plants but really enjoy learning about them. They way you presented this information gave me a greater understanding of turbine engines. I have a lot of respect for you and Mike on your expertise in your respective fields. Thanks for the video. I really enjoyed it.
You are the very person I wanted to analyze this event that happened to Mike's engine
Had a pt6 grenade on me, in a caravan c208. Audio of it destroying itself in the background on my mayday call on my channel. Good times. It was sulfidation corrosion on the compressor turbine locking the blade in place on the fir tree area of the disc. This stopped the oscillation in place that would normally happen and made the blade bend until it failed and cleared out the engine. The gas generator moved back 3/4’s of an inch in its mount. It actually triggered an AD that affected all engines with the same wheels.
THE best teacher on the internet imho. Great post.
Thank you JZ, great info as always. Glad you’re on the mend.
Hi AgentJayZ,
I'm pleased to hear you're recovered after your injury and that it didn't stop you getting to Oshkosh.
I've taken a look at Mike Patey's video, all 42 minutes of it. He's obviously very grateful and very relieved that, with plenty of altitude, he was able to glide into an airport, rather than plough a furrow in a cornfield, or do an emergency landing on a highway (see below). However, we don't get too much of the engine itself and he does keep describing the event as an "explosion" when it was clearly an uncontained engine failure.
No doubt P&W Canada(?) will be able to home in on the root cause of the failure, but it does appear to have been a power turbine stage 2 blade failure, with possibly one blade causing a 'haircut', hence all the 'shrapnel'. As the aircraft was landed safely at an airport, will the NTSB become involved?
We had our own emergency landing locally at around 1800BST on Thursday. A light aircraft on short finals into Gloucestershire Airport (30 minutes north on the M5 from my home) had a suspected engine failure just a few hundred metres out and landed on the Armco in the middle of the A40 Golden Valley bypass, presumably because the road would have been really busy at that hour. Fortunately, the pilot walked away unhurt.
Really amazing analysis and a great explanation of how the PT-6 works.
Mike is probably one of the smartest men alive! Great man!
Nice to see back and healthy! I follow Mike Patey (Draco is probably my favorite plane EVER!) , but also enjoy your videos, and am looking forward to your insights.
Way back in the late 70s we had a J52 turbine disk disassemble itself in flight. It effectively cut the A-4s tail into pieces, penetrated the wing fuel tank, and caused the pilot to have to eject on fire and out of control. Fortunately the pilot was not hurt and it happened over ranch land so no damage or injuries on the ground. It was the first crash I was on. It was obvious what happened as soon as we saw the enjine. Everything behind T2 disk was gone. 2 turbines, their guide vanes, seals and other assorted goodies successfully and rapidly disassembled themselves in flight. This was a excellent video and description for people who donot know jets and how they work. Well done.
Always a pleasure to hear you about jet engines, keeping everything tight on the vocabulary used to describe various parts and processes.
Sorry you got hurt. Really glad you’re on the mend, up and around.
Love that you rode your motorcycle there. Love it! I have a FJR 1300 and that's another bike that goes thousands of miles with not many issues ever. Thanks for the video.
Your videos are some of the best…and enjoyable from this A&P/ pilot👍
Thanks. Your opinion counts a lot!
Thank you for your video! Feel like a lecture and I enjoyed every seconds of it.
As a retired pilot and survivor of near 12,000 hrs as Capt of helicopters, both single and twin, I can tell you engines fail. Twice after maintenance ! Once the engineer lost a bolt whist refitting the engine intake after a 100 hr. You could see the new bolt fitted in the 12 o'clock position. A search was made and the missing bolt successfully found hiding in the corner or the engine intake. later in flight some hours later it made its way into the engine causing a failure with massive vibration. After the emergency landing another engineer found the offending bolt chewed up and back in its natural hiding place in the lowest corner of the intake. It had repeatedly bounced off the compressor blades, breaking bits off all over the place, those went through the engine. The 100 hr engineer lied about the situation, saying he never replaced the bolt. saying he never lost the bolt. yet we had the "old" bolt and the evidence of the newly fitted replacement ... Its colour was like new the others were darkened with dirt and soot. Then with other evidence and the passage of an ongoing legal dispute and 5 years later he confessed. The claim against his insurers was eventually met. Is this form of dishonesty unusual ???? No... the conflict of interest is there. Disciplinary action or a white lie ??? The second was in a single engine type. A hired helicopter, I noticed on first start it was slow to spin up and hung a bit. The engineer said it did that !! I was inexperienced at the time, and noticed it was maybe 5 seconds over the start max on first start of the day and quicker in subsequent starts. But it flew well and made the power. 2 days later, cruising at 2000 it exploded. The only word for it. Massive bang, yaw and instant lost of power auto landing and perfect short run on on smooth grass !!! Some blades had cut through the airframe and exited beyond, some had gone through the baggage compartment, some had hit the rotor blades. Did I say it went with a bang ??? I collected a handful of blades scooped out of the engine bay as souvenirs. Then the other two were in petrol types. The first the very next day after maintenance and the fitting of a new engine! Of course everyone pointed to the pilot as cause, yet the set up in my opinion lead to the waste gate not being calibrated properly meaning partial power or in my case, a restriction of air, insufficient for sustained flight. Again engineering told the truth as they knew it saying it was impossible, yet it happened and all evidence pointed to a faulty install. The next was my fault ..crop spraying an underpowered petrol heli running on minimum fuel all the time, dipping the tanks for accurate quantity reads and frequent refuels every 15 minutes, and error occured, My ground guy dipped the tank (it had two interconnected) the procedure was we only dipped one tank. I had landed in the corner of a field, it was ever so slightly out of level yet allowed the dip to be in error. The dipped tank gaining a benefit of fuel from the other slightly higher tank. Not quite on level ground gave a false dip stick reading .... at the 12 minute stage the engine stopped, whilst I was in the middle of a torque turn with a bucket close coupled below on the hook. It went quiet whilst the nose was up at 70 degrees in the turn, I saved the bucked and the helicopter and landed perfectly in the last seconds cutting loose the bucket and kicked the tail of the helicopter to one side so I did not land on it. Later as an owner of helicopters engaged in public transport flights we flew without incident for years, except I came across dishonesty more than once. Again this conflict of interest came into play, after damaging the helicopter the engineering out fit tried to cover it up, without simply saying what had happened. So in nearly 49 years I found dishonesty amongst engineers common and expensive. Their motivation to cover up being paramount.
No different from any other skilled trade. Unfortunately from experience this type of behavior includes doctors/surgeons as well.
I’ve experienced one engine failure in flight due to mechanic error, numerous issues right after a maintenance event. Some could have been serious. One time we where transferring fuel and deducted that the fuel harness was wired incorrect after the event.
Wow respect
Sounds like a much better time than the last time the trip was attempted. Rubber side down check. Quarantine restrictions, wtf? Keep posting. I'll keep watching.
I feel you may be spot on. I'm retired now but had worked on the PT6A series engines for many years. I started in 1980 for the Pratt & Whitney Canada Service Center Network in Burlington (Vermont) and retired in 2013. I have many fond years working on PT6 engines!
Great to hear from you. You opinion is worth a thousand times more than most of what seems to floating in from the inexperienced advisors...
Thanks for the perspective of a guy with experience.
We at Orange Coast Collage got to take apart a PT-6 and an Allison-250 for the A&P program. Both are incredible designs. The Gas flow in the PT-6 is trick.
I’m proud of you for making the journey on the bike. I just sold my 1985 k100 RT with 123000 miles and it still ran great and ever leaked or burned oil. Great bike brand. Replaced it with a R1150rt with 98000miles and I love it. Keep them coming brother. I always learn from your videos.
You're supposed to borescope them every 400h or so. We borescope our -42s when we do the nozzle changes.
Again, he's experimental so he doesn't have to follow the same MSA as we do on engines operating under CAR 703.
Also the nomenclature we use on PT6s on aircraft is Ng and Np for the different speeds in the engine. It says in the King Air POH that you should idle the engine until ITT stabilizes for about 1:30... almost no one does it despite being written. We can tell when we do a Hot Section inspection because you can see the tip rub marks on the segments.
How involved is the boroscope inspection? Can you do it easily and routinely, or do you have to remove a ton of stuff for hours to stick your camera and look at the naughty bits?
@@nraynaud Depends greatly on the engine. Pretty much anything made in the past 60yrs had borescope plugs that makes the job easier. Getting to the plugs and getting the borescope inside where you want it can be difficult. PT6's are pretty easy.
@@mytmousemalibu I'm still thinking of Mike's airplane. If it easy, he might do it routinely without mentioning it on video because it's not a topic on his mind.
@@nraynaud It depends on how easy his cowlings are to get off. While its not that hard of a job after that, its not practical to do frequently and with failure like this, there is likely no visual indication of impending failure.
@@nraynaud on the PT6 it's fairly easy. we can remove a couple of the fuel nozzles and with a long enough borescope, go right the way around the circumference of the engine.
removing the cowlings for access is usually the most annoying part.
Missed your vids mate-used to watch you for hours during Covid. -love your refurbs of engines.
Hope you're healing up Jay! good to see your face.
Thx Agent Z for an informative and entertaining video. Glad to see you made it to Oshkosh EAA fly in inspite of your injuries. MP was lucky He didn't have a fire during his engine out. I like that you road your GS there. FWIW I ride also currently have RFS 525 Katoom and '14 Duc Mutley PP. I've been riding since childhood and have 3 daugters and 5 G'kids with all riders 6th one is 3yrs old but were working on it. Have ridden in So Pacific in USN and road Mex2Can off road in Y2k+1 and about 15 LA2Barstow 500m DS rides. Enjoy that GS.
It's luxury to have a teacher that know that exact engine Mike Patey use that well giving a great explanation that even I who have absolutely zero experience with jet/turbine engines could follow, and I'm confident you'll keep your cap.
I'd love to watch a collaborative video with @AgentJayZ and @MikePatey where you discuss, among other things, the engine failure Mike had. I am confident it will go viral in the aviation community on TH-cam.
Well that sounds like a great idea. Let's see what Mike has to say about it.
I can't believe I actually found this video entertaining... well done!
Another fascinating video. My plane has the Czech PT6ski turboprop, aka, the Walter 601. Very similar design as the PT6. In addition to the borescope inspection every 100hrs we also have a combustion chamber rivet check done. Like you mentioned, something coming loose in the combustion chamber can cause a domino effect in the turbines.
I really enjoy your videos. You know your craft well and you do an excellent job of explaining it to us novices.
Thanks for the very interesting video. I had never really thought about how that engine was laid out but it looks like a clever design and you did a great job explaining it.
Fantastic, thanks! As soon I saw Mike's video I thought, "I'd love to hear AgentJayZ's thoughts on that."
Nice video explaining what might have happened with Mike's Pt6 engine (I saw his video as well). It will be interresting to see the result of the investigation of the Pt6.
You're talking about Mike being a big deal, well don't put yourself down like that, you're a pretty big deal too! Very few people can do what you do. I'm sure Mike would absolutely love to talk shop with you.
Thanks for the kind words!
Thanks for another very interesting video Sir. Equal Thanks for your respectful acknowlegment for Mikes skill & professionalism. Both of you have great descriotive information.
Got it. Clear explanation appreciated and I learned which is something I always enjoy.
Thanks from Ottawa.
Mike also I believe stated that that engine was not the original engine because he removed the original and sent it to P&W because of a HOT START and the engine that (BLEW UP) was from P&W and had a total of 5 hours in Turbulence but very High time.
HA! That's almost word for word what I said too. I know he's being really nice about it, but if I bought an engine and it blew up five operating hours later I'd be having a serious conversation with the people I bought it from. I doubt he buys things from anyone "as is" and without any reasonable expectation of quality.
You are simply terrific. A pleasure to witness even without me knowing anything about such fascinating subjects. Cudos Agent Z...
First time watching your vids, I like your presentation style and the way you present your info.
Thanks for the great breakdown of MP’s engine failure.
Great to see you again JZ, thanks for the explanation. Glad you are doing well.
Learned a lot in A&P classes, especially about the PT6 A/B. Very nice breakdown and analogy of how they work.
Dr. Turbine, another amazing video for engine failure analysis! ❤❤❤❤
Thank you for the kind words.
I'm from Houston, Texas and 38C(100F) is hot for anybody and everybody, especially with high humidity. Houston is the most air conditioned city in the world for a reason. Anyways, it's great to hear your thoughts on Mike's issue. I always enjoy your videos! Keep 'em comin'.
I've been to Houston once, in January. It was too warm for me, but I was impressed with the size of it.
My town is four minutes from the south end to the north... five in rush hour.
@@AgentJayZ Too warm in January?! That's about as cold as it gets here😂. As far as Houston's size, I love living here, but we could make it a more walkable city. If you don't have a car here, you're totally out of luck...
I love how turbine engines are both the simplest things and most complex things at the same time.
They're not even complex, but when you consider the operating temps and tight tolerances, they are amazing. Germany's first turbojets needed overhaul after a flight or two.
@@davemedin1113 The design is complex. Take for example single crystal turbine blades. Considered one of the greatest feats of modern engineering.
@@NotSure416 Advanced materials don't create complexity. Tolerances or temperatures don't create complexity. Engineering 101. Parts count or mechanical complexity does. A PT6 or non-variable stator turbine is way less complex than the piston powerplant in the typical GA aircraft, unless you're flying a 2 cycle engine.
@@davemedin1113 Car engines are also both complex and simple, but to a lesser degree than a jet engine.
Even though I assume you mean "car" engine, jet engines are much less complex. As you mentioned, some of the materials have to be esoteric with tighter tolerances, and the temp and centrifugal stresses are higher, but the fixed stator jet engine is about the simplest powerplant out there, both in theory and in practice. The ubiquity of the internal combustion 4 cycle engine just makes them seem simpler as they're more accessible. Watch one of AgentJayZ's turboshaft engine teardowns. I think he has a few associated with jetboats he crewed. If size is intimidating, YT channel Just Think has a Williams WR24-7 axial turbojet all torn down on a bench. Count the parts. It isn't a dud--he gets it running again. Or look at a few of the minis like the new Czech TJ100-series turbojet engines. The Czech engines are actually powering piloted aircraft like the Sub Sonex.
Excellent analysis as always. Thank you, Jay Zulu.
At 23:53…
…also air changes at least 90 degrees at every guide vane/compressor/turbine stage as it navigates the labyrinth. It’s path definitely doesn’t go straight thru.
Just a question - Is a visual inspection really adequate to detect these cracks or is it more of the case that it is "better than nothing" if you are not going to actually tear the engine down? Does the borescope provide increased magnification to allow better detection?
1 - Visual inspection is the procedure specified by the manufacturer, providing it is performed at the required hours of service interval, and providing there have been no overtemp events. Engine teardown is done at the specified overhaul interval.
2 - Boroscopes have adjustable magnification, and adjustable...extremely bright illumination.
Been a while since I've chimed in! I do watch Mike and was hopeful you would respond Jay. I pretty much had the same conclusions. A little ironic but last month I saw a JT8D on an MD-88 let go right before my eyes. A loud bang, smoke, and a cloud of very expensive metal ejecting from the exhaust duct. We found out it lost a nozzle segment via borescope investigation. Combustors and compressor were fine. It was violent enough that the cases swelled and it blew a number of nozzle segments out into the turbines and wiped it out. I have a few souvenirs from that. Luckily it was a ground run. No fire, no injuries. Quite a thing to see. Our borescope is pretty tricked out. It can take dimensions and 3D model images. Full 360 articulating head, all the good tricks!
Did you witness the engine spitting chiclets? That is a rare and awful privelidge. I've seen it once.
@@AgentJayZ You could say that! Our hangar doors were open and I like watching & listening to those old low-bypass engines make smoke & thunder. He was slowly advancing the throttles, not quite to takeoff EPR when it let go. Boom! It spooled down pretty quick and seized. Took a good long while to get the ramp cleaned up. Some of the guys had nearly full turbine blade or stator blades for souvenirs, mangled of course. That engine had just had some hot section work done on it by an outside vendor. It was more than likely a maintenance error that caused it rather than a true engine failure. Not good but quite a rare spectacle to have witnessed!
I'm not even subscribed to Mike Patey's channel but have watched some of his videos about the Turbulence. Watched the engine failure emergency video yesterday... and here I am, absolutely fascinated and glued to the screen, watching some other channel's possible failure analysis.
1:44 That was my favorite part of the video. Cheers my CanAm counterpart from way too sunny and miserably hot South Florida. I know Sun-N-Fun is a TRIP for you, but if you do make it to Lakeland I will definitely drive over. Till then my Friend.
Hello from Australia; your comments at around 20:00 regarding letting the engine cool before shutting down. As a model turbine flier, I have often been asked by other modelers why I throttle up to about 30 to 40% before shutting down; why I do this is when the data terminal is plugged in I have noticed that the EGT drops to the low 500 degrees rather than the 600 degrees at idle power setting. Am I wasting my time or does this make a difference to the longevity of the turbine? Thanks.
You are doing exactly what's best for the engine, and exactly what all the warbird jet pilots do.
Shutting down from the minimum EGT places the least thermal stress on the hot parts.
"Ground idle" is set to minimize thrust and fuel consumption.
If you can afford the fuel and have good brakes, find min EGT, run there for a couple minutes and then shut down.
Well done, sir!
@@AgentJayZ Thanks for the reply; I have already had one with a catastrophic failure of a cast compressor wheel (only 47 starts and 4.6 hours of run time), so the more that I can conserve the engines, the better. I have only been letting the temperature stabilize and then shut down, but I will keep it running longer. After shutdown, I use a battery air blower in the intake duct for a couple of minutes also. Thanks again for the reply.
Remember the EGT is showing the temp of the exhaust gases, but what you are really interested in is the temp of the metal parts in those gases. Give them time to reach the temp of the gases.
I would not blow air through the engine after shutdown. That speeds up the cooling. You want the temp change to be nice and slow.
After shutdown it will not heat up again unless it's on fire.
@@AgentJayZ Thank you for the information, I will change the cool-down procedure. Thanks again.
Thanks for the great explanation!
I’ve been watching you for a number of years now. With that said, I no more watched Mikes video thirty minutes before running across yours. Definitely got my attention with the subject matter. Yeah he kinda exploded the fan disk or maybe two. Peppered his airframe all over with nice coin sized holes. It’s good he was able to make it to a nearby airport and put her down safely. The one big take away I got from the event is he stressed taking safety seriously and practicing emergency procedures over and over so your well versed in piloting your way down.
AgentJayZ, glad you felt better in time to go to EAA. The heat and rain were a bit brutal this year. This video is another great perspective, one of the reasons why I have been following your channel for years. I hope you enjoy your boxer for hundreds of thousands of Km miles. We sure did ; )
Worked on CH-135 Twin Hueys with 408 Tac Hel Squadron back in the day. P&W Canada PT6 twin pack in those venerable choppers. If not mistaken its replacement the CH-146 Griffon that replaced it uses a later version of the PT6 twin pack. Robust, proven power plants. Don't hear about many failures so this is very interesting.
Great analytics of a serious subject. Anxious to hear what went catastrophically wrong with Mikes PT-6. And I agree completely with your sense of the build quality and research that went into the assembly of parts and pieces that became the world’s fastest turboprop. It’s amazing, as is the pilot. Textbook procedures culminating in a well thought out process of safely landing and zero injuries ( probably slightly elevated heart rate, but no data on that one)😂. Again, great video, and I know that he would gladly send you a cap!
OH NO! Glad to hear you are on the mend!
THOSE ARE FANTASTIC MOTORCYCLES!
At 23:37 you mentioned that you saw a compressor blade that broke off and moved upstream and the upstream compressor was taken out. Could you please say a little bit more about how it was determined that a broken downstream blade hit an upstream blade as didn’t that upstream compressor send a lot of bits all over the place (as in downstream). This is not about questioning anyone about the determination but to learn about something that probably has an interesting story. It would seem plausible that a compressor blade is loaded towards the upstream direction. This is similar to fan blade fragments being ejected out of the front of a turbofan engine upon breakage under certain conditions (the NTSB review of the Southwest flight that had a fan blade break talked about that and a 777 that had hull damage forward of the damaged engine was traced back to the titanium fan blade). I find such things that at first seem counterintuitive but on more rigorous inspection to be possible, to be fascinating.
Was a long time ago in an industrial LM1500 (J79), but one stage of compression, and all behind it, was completely gone, and the one in front of it was fine. The stage in front of that one had impact damage to the back of the blades... the shapes of the impact on the back of those blades had threads that matched a 1/4-28 bolt, which must have been the cause of the initial damage...
@@AgentJayZ
Many thanks, curiosity satisfied, have learned so much from your videos, can never get too much!
@@AgentJayZ Immediate compressor surge from the loss of compression when the trailing stages were destroyed?
I went to Oshkosh. I talked to P&W at show (they know the Patey and sold them upgraded engine for their PC12). The 1st hot section turbine disk failed. Yes UT blew parts out exhaust.
Simplest explanation is usually the best.
It was a lot of fun. I saw Mike looking around the amateur kit sellers on Saturday I believe. He has incredible energy and ability.
His energy level makes me wonder who he has on his payroll to sleep for him.
I was up at Oshkosh on Friday and Saturday. Got to see the MiG-23 on static display, and watched it taxi out for take-off... and then taxi back. 😞 Saw the restored P-47 fly on Saturday, and it was gorgeous! I took pics, but there are some great youtube channels with excellent videos. I recommend AirShowStuff videos and Airailimages. The Dronescapes channel has some of the Warbirds in Review lectures/talks too, which is usually excellent.
ILMFAO! The "rocks and sticks and little birds" comment is a classic!
Thank you for this update on Mike Patey's video.
It will be interesting to see if that indeed was the cause. The PT-6 is arguably the most reliable engines ever produced, and for it to happen to Mike is even more statistically unlikely.
Am thankful he was ok.
Amazing engine and explanation of what made it blow. Thank God he didn't crash and burn so now they'll be able to ascertain what caused that engine to explode..! Oorah, Bud
Excellent explanation as to root causes of failure Agent JayZ.... I hope Mike Patey watches your video explanation of failure causes..... I am betting someone "claimed" the engine got a complete visual inspection that wasn't done properly, or, the history of the engine, being used was lost, and a couple of hot starts by the previous owner/ pilot did the damage.
There is at least one program for life extension of a pt-6 that I know of. The one I know is called MORE, which takes a 3600 tbo and moves it to 7200. For the higher time, you are required to do certain maintenance at a lower time interval, ie 300 in stead of 400 hours and more inspections of the hot section. Fed ex was the creator of the MORE program if I remember correctly.
As a Canadian passionate by aviation, IT geek/DYO mechanic/you name it, I absolutely love to watch your videos. You mentioned that you highly suggest to do a borescope inspection of the hot parts especially when buying a second hand engine. Understanding how critical this process is, should that be done by the seller and comes as an mandatory step when selling this type of engine (i.e. inspection certification)?
The rules are very relaxed in the experimental aviation category.
very good video.... me thinks you have a very valid point and I am going to say Mike did not tear that engine down far enough to prove/disprove the theory... But betting you have it nailed...
Glad to hear you're on the mend!
I was hoping you'd chime in on Mike's PT6, your expertise is appreciated. Hopefully @MikePatey sees it!
Point of information from undergraduate level metallurgy: metal doesn’t crystallize from being overheated after annealing. The grains of metal are in a lattice structure that is already a “crystalline” structure. Overheating to 0.3 to 0.5 of melting temp can cause reorganization of the crystalline grain structure usually discontinuous to where one section has a different grain structure than another section of the piece of metal. Viewing the surface of a break reveals what is clearly a crystalline structure so observers may deduce “Aha! It crystallized causing it to break.”. In a sense, but it was always crystalline.
You may not have learned the specialized stuff in school yet... like the fact that aviation gas turbine blades are usually one single crystal of metal.
I was in error using that word however. The overheated blades change from having a smooth surface texture to having a surface that looks and feels like sandpaper. They seem to become more brittle, and you can often find tiny cracks in that surface.
The video linked to in the description called Removing Blades shows an example of this.
Great analysis. I think you are spot on.
It will be interesting to see the inspection report.
Thanks for the great video.
B58 guy.
I kinda wonder if the engine had a hot start at one time or another i know my engines have to be spolled up to cool them down before starting some times after a heat soak when getting fuel ? Gary K
Great job on explaining the reverse flow engine like the PT & the Walter! Awesome Job!
Mike said that the prop instantly stopped in his video. I had this happen to me in a Twin Otter with PT6-21 engines. Yes it gave me warning signs. When I shut the engine down between flights I cut hear a ticking sound. Had a mechanic take a look and was told it was a tach or accessory drive making noise and it would be fine. LOL 4000 feet after takeoff next flight the prop instantly stopped, Broke all the motor mounts except 1. Turned out to be a gearbox failure. If the engine fails on a PT6 the prop should continue to spin until you feather the prop. Maybe this was his issue?
Have a look at his vid about it. "instantly" is a word with many different meanings, depending on who you ask.
I saw his video and he clearly said the prop stopped instantly. If he didn't mean to use those words, maybe he needs to clear that up??? A prop on a PT6 does not stop instantly unless the gear box is damaged. It will free spin until you feather the prop, then it will stop. He is leading non experienced pilots down the wrong road if it didn't stop instantly. @@AgentJayZ
@@isprouse The Propeller/transmission is directly connected to the power turbine, so if the engine seizes, so would the prop. Unless it has a one way bearing like that in a helicopter.
Chippy... the PT blades broke, stuff was mangled, but I'll bet you the PT turned at least a thousand revs until it stopped moving altogether, down from 34,000 rpm to zero in a screeching, grinding end.
That is not what I call instantly.
You?
@@AgentJayZ I doubt instantly. The inertia of the prop alone stopping instantly would cause more damage.
Good explanation of the working engine
I actually caught a break and at least got to watch the live stream of the flights this year. We'd just gotten back from a southwestern museum tour of old warbirds, with our final stop in San Marcos to see a still-flying C47 (not a jet, but Very cool!)
Speaking of iron butts, I just saw the story of the german fellow who cycled (like pedal powered) from New York to Oshkosh! Holy cow, that's a feat at any age, but this guy easily had 15 years on me! Glutton for Punishment mode engaged!
It's absolutely critical that you allow the engine to cool down before you shut it down...just like the manufacturer calls for. The PT-6 engines are extremely reliable.
Mike said that he got the engine from the manufacturer of that engin . It was used my question is did they inspect it befor they sold it to Mike?
Mike clearly states it in his most recent video that it was the PT2 blades gone (PT1 damaged but not gone) and that the engine while used had come from P&W.
Excellent video Agent Jay Z! Glad you made airventure 23’ wish I crossed paths with ya I was tenting with my wife in Paul’s woods campground. Very good man love your new bike. ✌️✌️
Always like your videos. Another well done explanation. Thanks for sharing!
Very interesting, thank you for posting
Professor JZ comes through again with his honest opinion of Mike's engine out. I'd bet my Bengal season tickets that engine had a hot start earlier in it's life rearing it's ugly head later at 30.000 feet. The forensic wrenches will find the problem and share their findings with the community. We live through the past.
Maybe you should give your opinion on the Titan DSV. Just kidding. Seems like every youtuber is capitalizing on that. I like that you're an engine tech that makes youtube videos rather than a "youtuber". Anyway, thanks for this video. Very easy to understand!
My Honda ST1100 motorcycle had 142,000 miles on it when I hit a deer around Eagleville, California back in 2003. The bike hummed like an absolute sewing machine. In addition, I didn't baby it... I flogged it mercilessly up and down the full range of the tachometer during tens of thousands of miles of Appalachian mountain twisties tip-over wing dragging.
My Suzuki Bandit, the 600cc version, has over a 100k on the clock too. It's an air cooled engine that gets beat on far worse than the ST1100. It still runs like a scalded greyhound even though I've been through numerous sets of footpegs.
Modern major marquee motorcycles rot more from sitting unused than constantly piling them up with mileage.
Mike Patey... An incredible experimental aircraft personality. But, like Alex Honnold, the incredible free soloist rock climber, pushing the envelope eventually breaches the envelope.
Hopefully, they'll both be with us for a long long time... But, flying too close to the sun, too often, and too long has its predictable conclusion.
I like the riding position of the ST1300 so much more... but the engine of the CTX is retuned. It only makes 84 Hp, but it makes locomotive torque.
If I had the time and space, I would put the CTX engine in an ST...
Maybe it's just cams and the ECU...
Awesme class room session Jay, Hi from NZ
Great to hear your take on the engine failure of Mr. Patey, very educational thx so much this!