421 Fatal Probable Cause Released

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  • #84760
    bthomason
    Participant

      The NTSB has released the Probable Cause statement of the fatal accident that took the life of TTCF member Tim Johnson in Dec. ’12:

      The pilot’s failure to follow established engine-out procedures and to maintain a proper airspeed after the total loss of engine power on one of the airplane’s two engines during the initial climb. Contributing to the accident was the total loss of engine power due to a loss of torque on the crankcase bolts for reasons that could not be determined because of impact- and fire-related damage to the engine.

      Full report is here: http://www.ntsb.gov/aviationquery/brief2.aspx?ev_id=20121208X53119&ntsbno=ERA13FA082&akey=1

      Many of you know, I owned this airplane and sold it to Tim. He was a great guy and although new to twins, he seemed to be doing everything right from a training and safety standpoint. I wish the cause of the engine failure could have been determined. But what really troubles me is the report of the nose pitching up after the engine failure. That’s the kiss of death in an engine-failure-on takeoff situation. Speed (and control) bleeds off at an alarming rate. Sims are very good at demonstrating this. I just interviewed a check pilot for a 135 operation that flies 421’s. They train their pilots with low level engine cuts using the mixture knob. He said the first time most pilots experience this, they never get in enough rudder or lower the nose enough. “You have to see ground in the windshield”, he said.

      If there is ever time for aggressive action, it is in this type of situation. I think we all know what to do: train, practice and expect an engine failure on every takeoff. It’s the price we have to pay to fly twins safely.

      #102747

      Bob,

      Will the interview of the check pilot appear in the magazine soon?

      #102749

      From the accident report:

      “The item 98 write-up on the most recent annual inspection invoice stated, “Investigate no oil pressure on left engine; reprime left oil pump, filter, standpipe.“When interviewed, the proprietors at the maintenance facility said that the airplane’s engines sat idle for an extended period (weeks) due to the annual inspection and the painting of the airplane. Because engine oil has a tendency to “settle” in the sump, and cause the oil pump to lose its prime, the engines were motored. When motored, the left engine showed no oil pressure. The oil system was then primed, and oil pressure was restored prior to engine start.”

      I wonder how long the left engine ran before it was noticed that there was no oil pressure? The mechanic’s post-accident interview says that the zero oil pressure was discovered during a precautionary motoring. Since motoring requires the removal of 6 spark plugs, the motoring precaution is one that very few shops take the time to do.

      Unless the paint shop did a lot of GTSIO work, it may not have known that GTSIOs are notorious for losing prime. If the paint shop was familiar with GTSIOs losing prime and expected there to be no oil pressure, why did the invoice say “investigate no oil pressure”? Wouldn’t the invoice simply say that the oil pump was primed?

      I wonder if the invoice mentioned motoring the right engine to confirm oil pressure?

      #102750

      Seems like a good place for the market to have digital Oil Pressure data that can be an alert and display.

      Engine information warning that there was no oil pressure at X date and time for X time. I know that some of the engine monitors are setup to do this like the 960’s but not sure it’s displayed on the screens.

      My plane will sit for a couple weeks pretty often (414) wonder if this is a danger to us all who have them sit for 2-3 weeks?

      #102752

      There is also the question of whether that truly mattered or caused the engine failure. If it was run for an extended period without oil pressure, obviously that’s bad.

      I wonder if there will be a deeper investigation into the engine as to why it failed.

      No matter what, very sad, and a reminder of the vigilance we all must maintain with our planes.

      #102753

      GTSIO’s are funny about this. Some will lose oil pressure after sitting or oil changes, other don’t. Mine doesn’t do this.

      #102754
      Gerald T. Alves
      Participant

        A friend of mine bought a 1982 421C and took it straight to the paint and avionics shop. Plane was there about 4 months. He went to pick it up and taxied to the run up area. No oil pressure and taxied back so the engines could be primed. About 100 hours later he was in the middle of a pre take off run up when the left engine just suddenly froze up solid, could not turn the prop. If this would have happened 3 minutes later right after TO?.. Engine was replaced and 100 hours later the right engine suddenly started making a lot of metal and was replaced.

        There is a very good possibility damage was done on that first start up at the paint shop.
        Jerry

        #102758

        I found it strange that fuel selector was off and the gear was down and locked? You’ve got to wonder what was happening.

        #102761
        quote BThomason:

        Many of you know, I owned this airplane and sold it to Tim. He was a great guy and although new to twins, he seemed to be doing everything right from a training and safety standpoint.

        Tim and his dad sat at the table behind me at the TTCF Engine/Frame seminar at Defiance. I knew he was new to 421 but he knew the plane and systems. He just did not have much time in this airplane or multi engine planes. It was obvious he was interested in learning or he would not have flown up from Florida to be there for two days of learning. Tim was proud of that plane, it was an impressive 421. I really enjoyed talking about flying with both of them.

        I was so sad to learn about his death, especially for his dad as they were both shared the love of aviation. Plus he left a young family without him.

        It really hit me how much trouble can happen in just a quick few seconds. I think about Tim’s accident every time I line up for take off.

        Jim

        #102762
        quote SGERBER:

        I found it strange that fuel selector was off and the gear was down and locked? You’ve got to wonder what was happening.

        One thought: maybe he quickly identified the failed engine and feathered it then was working on securing it, but hadn’t selected the gear up. Then tried to keep climbing at the cost of airspeed, resulting in the single engine stall/spin or Vmc roll.

        #102775

        It’s easy to reflect on these things from the comfort of our living room couch, and a very different thing to be at the controls when something like this happens so I don’t want to pass judgment on Tim or the outcome of this sad accident. I am sure he did everything he thought possible to get out of a bad spot, sadly without success.

        However, I would like to provide some reflections regarding technique.

        There are many experienced Twin Cessna pilots on this forum, and I surely don’t want to be preaching to the choir or attempting to teach something to someone with more experience than myself. Nonetheless, I hope these reflections provide some food for thought.

        The “official” training curriculum for twins is – CONTROL (yaw, roll, airspeed)– POWER (everything full forward) – DRAG (clean up) – IDENTIFY (failed engine) – VERIFY (reduced throttle on suspected failed engine) – FEATHER (fail engine prop) – SECURE (complete checklist) – LAND.

        I just returned from my yearly recurrent at Simcom and the experienced and knowledgeable instructor who gave me the class shared the same thoughts I have about this method.

        The thesis is that if the day comes when any of us actually have to deal with an engine failure after takeoff at low altitude like Tim’s accident and we try this, we will surely die. Low on altitude and low on speed, with one engine out, you just don’t have time to be farting around with all this baloney. You have a few seconds to react and extract whatever little performance your sick bird may give you.

        What we practiced over and over ad-nauseum until I convinced myself once again that there are better ways to at least have a fighting chance, is the following:

        Turboprop aircraft usually have sufficient thrust and power to get out of an engine loss emergency on takeoff easily due to the excess power a turboprop engine provides. They also have an important safety feature called Auto-Feather. If you ever lose an engine in almost every turbo-prop I know of, the prop will automatically feather itself and allow you to react quickly and climb without the good engine killing you.

        The technique is you (the pilot) become the airplane’s auto-feather, and it boils down to this:

        1. You lose the engine with the gear down before or after rotation – power comes back and if you’re in the air, make a controlled landing/descent right side up. This is better than any other alternative.

        2. After rotating and having pulled the gear up, your hand should go immediately to the prop controls – not the power controls or anywhere else. If you lose an engine, the airplane will swerve to the side where you have the bad engine. Immediately pull the prop control of the engine on that side and fly blue line like your life depends on it – it does. You essentially become the airplane’s auto-feather.

        3. Then – do everything else you would typically do to get back on the ground safely.

        If you can, I would suggest you try this in the simulator and see how it works. There may be other ways, but we tried this in various scenarios and timed our reaction times. Both my training buddy and I were able to regain control of the airplane and get it to start climbing with the least amount of altitude or directional control loss than trying anything else.

        If there is something we can gain from these unfortunate situations, is to learn, practice and be prepared in case it happens to us.

        #102776

        Alex, great feedback. I have a sim at home that I have built and I have posted my information in the forum. It was a bit costly to build it out to support a Twin Engine with a good setup.

        The complication gets even more so when you throw in going IMC at 300-400ft and then loosing the engine. It’s good to do this training in VFR and IMC right after takeoff. I think learning to watch what happens when IFR and you loose the engine is also a good way to train your brain about what engine to feather.

        The other thing I’ve been toying with is trying to find a 402 freight plane in my area that I can go out with them.. Usually they run around all the time, do a missed approach, etc when they are training their 400 freight pilots. I heard one guy in my area has as much single engine time in a multi engine airplane as I do ASEL total. That would be a good guy to fly with. He practically fly’s the 402 like it doesn’t have a second engine.

        I would agree that I would never make any judgment of any accident. It’s a difficult thing that I hope I never have to deal with on take off for sure, but in the event I do I want myself and my family to live.

        #102779

        Alex, I agree with your method of handling engine outs when low. That’s what I’ve practiced for years and I believe it’s much better than the initial multi curriculum.

        My trip to SimCom last year seemed to indicate that. The 310’s previous owner and I went, and we both do this (actually he taught it to me). We successfully flew out of every engine failure, no matter how heavy and how hard he tried to make it for us.

        Then we went into the 425 Conquest sim. That plane has an autofeather. One of the reasons turboprop have them is the increased propensity to Vmc roll when a prop is windmilling. Since we don’t have autofeather, we disabled it. The instructor protested, saying “You can’t do that in this plane, it’ll flip over. I’ve never seen anyone fly out of it with a failed autofeather.”

        Both of us flew out of every engine failure on the plane. He started at Vyse, then kept on making it lower and lower on airspeed. Still flew out of it.

        We have no way of knowing what Tim did exactly, and like Alex I certainly don’t want to second guess his actions or presume that it can’t happen to me. But if we all remember that it can happen to us, maybe it will happen to fewer of us.

        This brings up another question. Has anyone ever considered coming up with a pre-oiler for our planes? I would buy them. It wouldn’t need much, just enough to make sure the system had oil prior to start.

        #102784

        http://www.oilamatic.com

        Currently certified for 414 & 414A. I am trying to work with George to get it certified on the 421. The system itself is very reasonably priced. The only pricey item on the 421 is that an oil plug needs to be welded into the drain pan which requires lifting the engine off the bolts to remove.

        You essentially just hold the switch down, let the pressure build, release and start like normal.

        #102786

        By the way – one thing I forgot to mention on my post, is my technique is – do not rotate and climb at blue line. Speed is a better friend than altitude. I normally rotate and accelerate in a shallower climb building up speed (maybe 120-130) rather than pitch it up to blue line. If you lose one, by the time you get your act together (and if you happen to be slow that day), this will bite you and you’ll find yourself quickly losing speed – so any extra airspeed will be a welcome safety net.

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