This story is written by an anonymous Jetprop owner who unintentionally damaged his engine. Both of us are hopeful we will be able to educate pilots so they can avoid this expensive mistake. Here’s the story…
While not a true “pro-pilot”, I do take my aviation experience seriously. I’ve steadily moved up in airplanes over the years, doing so only when armed with as much knowledge and wisdom as I could gain. I flew an A-36 Bonanza for 13 years prior to buying a Jetprop and it took me over two years to find the right aircraft. I almost bought a Meridian and did three pre-buys on three different Jetprops. While seeking the right airplane, I spent hours on the phone with Rocket Engineering, Kevin Mead, other mechanics, and Jetprop owners. I even flew in other owners airplanes just to make sure I was making a good decision.
Finally, I found the right airplane and closed a deal. After returning home from the required training I hired my local instructor to be a safety pilot and continued to practice until I felt completely confident in the Jetprop in instrument conditions. I’ve trained with him for years. He is an accomplished instructor and corporate Citation and King Air driver.
In addition, my background is agriculture. I have been around equipment and engines my whole life. As my dad was an ag pilot, I was raised in the shadow of airplane wings since I can remember. I even built my first V-8 engine at 13 yrs of age. I understand mechanical things very well.
My point is whole introduction…I’m an mechanically-minded guy, did my homework, got some good training, and believe my approach to aviation is quite professional. So with that background, how does a guy like me make a $200k mistake? It’s quite easy with a turbine…and that’s the point of this story.
After Initial Training (with an approved instructor who was really pretty good), I started working with my local instructor. The subject of how fast the Jetprop taxied kept coming up in our conversations. The folks at Rocket Engineering told me to, “bring the throttle just over the gate”. But, that didn’t seem to work as well as desired (although I’ve since learned that proper engine rigging is critical!). When all else failed, my local instructor told me I could, “Pull back the fuel Condition Lever to low idle”. So, we began pulling the Condition Lever back a bit while taxiing. That procedure seemed to work OK, and it became part my normal routine.
Then, one day as I was preparing for a departure, my engine began to shut down on the taxi ramp. I thought I must have pulled the condition lever back too far and so I pushed it all the way forward. This is the part of the story where all the knowing souls are laughing, crying, or screaming! But understand, at the time, I didn’t give it a second thought. I was following the combined, paid for, professional instruction I had been given.
You can probably guess what happened. The engine stalled briefly and then the fuel reignited and caused a significant over-temp event. Oddly enough, I really didn’t think anything big had happened. The event only took 8 seconds, during which my main concern was, “how was I to get towed back to the ramp if I could not restart the engine?” As an afterthought, I called Kevin Mead with the MMOPA hotline to get his thoughts. He nearly passed out when I asked, “Is 1200 ITT for 8 seconds a problem?”
In hopes that Kevin might be overreacting, I called a few other PT6 gurus to get their opinion. Everyone I called listened to my story and then responded with a tone as if someone had died. The air was so thick…“Gasp”, “Rot-Roh”, and “I’m so sorry” typified most responses. It was as if they knew something that I didn’t know, but everyone knew I was about to get an expensive education. One mechanic literally asked me, “why would you do something so stupid”.
The first quote from Pratt and Whitney was $225,000 and that was just the initial quote over the phone. They had not even seen the engine yet. In the end I received incredible support from the people with Covington Aircraft. My bill, while still considerable, was much less. I got an early Hot Section Inspection (HSI) with many parts that had to be replaced. Now my engine should be good to well beyond TBO.
Lessons Learned/Confirmed:
* Know your engine! Pilots need to know that a turbine is not a piston, and experience in one does ensure success in the other. I’ve flown 3 piston engines to TBO with not even a valve replacement, but this does not mean that I knew how to operate a turbine. I’ve since become quite an expert at the inner-workings of a PT6, but this education came a great cost.
* Problems can get costly with a turbine! There are 52 CT blades on a PT6-35. If one blade overheats, they all do…and they cost $1500 each. If the over-temp is bad enough you could end up changing PT blades (as well as vanes and other parts). My advice to future turbine wannabes? If you don’t know a CT blade from a PT blade you need to find out before you take over the bill paying!
* Type-specific training is a must! Although my CFI at my home airport is a super pilot and an all-around great guy, he knew little about the installation of the PT6-35 on a PA-46. His advice, although sincere and well-meaning, was absolutely wrong. Some King Air’s do have a “low idle” and a “high idle”, but this does not exist in a PA-46. Make sure you get good training from someone who knows your specific type of PA-46.
* Jetprop’s have little protection of the Condition Lever: The “stop” or “detent” on the Jetprop’s is arguably inadequate. If the Condition Lever is brought back, the engine will cease running. If the condition lever is brought back forward quickly, then someone will spend $200+K. If this happens in flight, a true emergency could exist. The Condition Lever should be mentally guarded at all times when flying. A pilot should know exactly which lever is being moved so the wrong one is not pulled. If a child rides in the front seat, extra care should be given so he/she doesn’t touch that lever. If someone moves to/from the front seat, a hand should be placed on the throttle quadrant to ensure clothing (or jewelry) doesn’t snag on a lever. Although not official, I’m under the impression that there have been quite a few errant movements of the Condition Lever by Jetprop owners, possibly even some in-flight.
* Get “Piston to Turbine” Training: My initial Training was good. I was taught to fly the plane well and my instructor covered all the systems in as much detail as is possible in the time frame allotted. What was missing is the class on “Piston to Turbine” training. Both engines turn a prop, but that is where the similarities end. I now have a fully paid for crash education on the engine and have completed my own hands-on HSI. Screw this up and you can spend $200,000 in 8 seconds…just a little more than two brand new piston engines…Humph!!
* I’m not the only one!!! I live near a military base and know the owner of a local engine shop that serves the military. When I discussed this problem with him, I learned that there are LOTS of military pilots that make the same mistake I did with your hard-earned tax dollars. This engine-shop owner said he sees “over-temped” engines from condition lever mishandling often, much to his business-enjoyment.
My hope in writing this essay is to educate and inform, not to throw darts at anyone or any company. What happened to me can happen to anyone that is not informed. Many pilots don’t know this, but the Red Lever in a Jetprop is connected to banker!! Don’t make the mistake I made!
