Turtlesfly
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Spoiler alert – I was in a multi, but still.
This is a bit of a long story, but hopefully something in here will help somebody someday.
I am the owner of a Piper Seneca II, but I haven’t had it that long – only about 3 years and with 150 hours on it (though I had some more Seneca time from many years ago at a flight school). This event happened in the cold of this most recent winter. The night before the incident, I drove to the hangar to plug in the Tanis engine pre-heaters. At the time of engine start the next day, the engine oils were 75 and 77 degrees F with the OAT being about 34 degrees. The taxi-out and run-up were normal. The power and propeller RPM performance during takeoff were normal. After selecting gear up, I got a flashing “TIT” high-temperature warning coming from the right engine JPI monitor, as the TIT had reached 1696 degrees (later determined, through engine monitor download, to have resulted from an uncommanded 3.5 GPH increase in the right engine fuel flow). Not only was the TIT about 250 degrees hotter than the left engine, but every right-engine cylinder’s EGT was considerably hotter than the left engine. Since the plane was light and the air was cold, I was climbing well to traffic pattern altitude, so I decided I had extra performance available to pull the power back a little bit to bring the temperature down on the right engine, but that did not do much of anything. I decided to discontinue the flight because I know my airplane well enough to know that those temperatures were not normal.
About on crosswind, and approaching traffic pattern altitude, the right engine and propeller felt like it was surging once in response to a power change, though I wasn’t touching any engine controls. A few seconds later, as I was turning to the downwind, all power was lost in the right engine. It was surreal: you feel an emergency should only happen on a “dark and stormy night” in icing with a plane full of passengers who are rushing into Aspen, or something. That you’re thrust into a situation where you’re on a peaceful flight, but now suddenly struggling all by yourself, can’t be explained. It definitely had a, “Uhh, okay, so this is really happening?” feel. It took many seconds to snap out of the mindset of, “Okay, plane. You’re joking. Come on. It’s ME, you’re owner here! I know you don’t act like this!”
I forced myself to go through the drill of “mixtures props throttles flaps-up gear-up identify verify,” but that did nothing since everything is where it already should have been. When I got to the step of “troubleshoot or feather,” I made an interesting decision (pay attention to this part): I decided to touch nothing until after I landed. I wasn’t on fire, and I didn’t need to feather the prop for performance. I was petrified of shutting down the wrong engine, or doing something that would somehow make the problem worse. And maybe the engine could come back? For at least a little bit of thrust? I continued the traffic pattern single-engine and landed somewhat uneventfully, though with great excitement. Upon opening all of the engine cowlings, no obvious engine damage showed. The engine remained “intact,” and did not shed parts, self-destruct, explode, or catch on fire, that I am aware.
After some investigation (that was only completed recently), the cause of the failure was determined: when the main fuel line comes into the fuel flow divider (or, “spider”), there are 6 nozzles that go to the 6 cylinders. Then there is the vent to the atmosphere. But there is also, what they apparently call in the industry, the “7th nozzle,” which is the line that goes back to the cockpit fuel flow gauge. When that line traversed the firewall, the connection had come loose. Very loose. Wasn’t even finger tight. When that line is loose, then it has the effect of sort-of “depressurizing” the spider, and can result in erratic fuel flows, up to a condition where the solenoid closes entirely, starving the engine of fuel. The mechanic who discovered this said that when he teaches his new mechanics, he even demonstrates that disconnecting that exact connection will kill an engine. The high EGT/TIT on takeoff was therefore correct: the engine was basically running lean because of the de-pressurizing spider. The engine surge later then, also made sense: the engine was running out of fuel. This was all discovered during troubleshooting, when the cowlings were off, by turning on the standby electric fuel pump (used only in an emergency in the Seneca), and when that was turned on, fuel sprayed everywhere, out of the loose connection coming from the 7th nozzle.
Going back to the actual event: had I decided to troubleshoot in-flight by trying the electric boost pump (which would have been a reasonable decision), it would have sprayed fuel everywhere and probably started a fire. It was probably a life-saving decision that I decided not to touch anything, and just let it windmill to the ground. It probably stemmed from my simulator training: no instructor ever tells you to go faster during an emergency; they always tell you go to slower. The saying in the sim is frequently stated as, “Enjoy the emergency.”
If I were in a Continental-powered single, I would probably would have tried the boost pump for sure, because you’re obviously more desperate. In a single, I would have either been doomed to an off-airport landing (if I didn’t try it), or doomed to a fire (if I did). I feel obligated to say at this point that twins are safer than singles, hands down. Period. Paragraph.
The fortunate element in success here, I feel, was that I was as well prepared as I could be for the event. I don’t mean to pat myself on the back, but just speaking factually: I am a former 17-year captain at a regional airline, and I am now a corporate jet captain, with about 12,000 hours of flight time. I recently finished my recurrent simulator training, and I had added a Hawker type rating last year. I have therefore done a significant amount of recent real-world flying as well as simulator emergency training. Additionally, in this incident I was flying my own aircraft out of my home base, at light weight with no significant terrain or weather on a cold morning. I had slept well, felt rested and healthy, and was not in a rush. The engines were already warm, and I had a lot of fuel on-board. It was daylight. I feel like all of these factors that I just listed all added “solid cheese” to the “Swiss cheese” model of accident causes, putting enough blockers in the way to prevent this from easily being able to have ended in an accident.
The shocking element in this is that the airplane only has about 100 hours since a major maintenance project was conducted on the airplane, soon after I bought it, where we conducted “firewall-forward” overhauls on both engines, propellers, mounts, hoses, accessories . . . everything. Additionally, just 5 flights prior to this, the airplane came out of an annual. Unfortunately, it sort-of proves Mike Busch’s theory of “maintenance-induced failure” as being more hazardous than to just let high-time engines run. But that’s a debate for another thread.
In the end, the fix was easy: 4 turns of a wrench and the problem was solved, and she has flown great since. I’m not sure if that gives me a warm and fuzzy feeling, though, for the mechanic then told me, “Don’t worry – every airplane you ever ride on – even airliners -- are just 4 turns of a wrench away from an engine failure, or some other major problem.”
I guess that is the risk we take every time we go up. We must be very trustworthy people in general. Or crazy. Or maybe both.
After this incident, I have learned my lesson: I have changed my mindset now, in that I view the maintenance shop as another thing in aviation that is constantly trying to kill me. Instead of blind trust, I now see myself as the last line of defense in everything.
Fly safe everybody. And put a wrench on all your connections yourself from time-to-time.
This is a bit of a long story, but hopefully something in here will help somebody someday.
I am the owner of a Piper Seneca II, but I haven’t had it that long – only about 3 years and with 150 hours on it (though I had some more Seneca time from many years ago at a flight school). This event happened in the cold of this most recent winter. The night before the incident, I drove to the hangar to plug in the Tanis engine pre-heaters. At the time of engine start the next day, the engine oils were 75 and 77 degrees F with the OAT being about 34 degrees. The taxi-out and run-up were normal. The power and propeller RPM performance during takeoff were normal. After selecting gear up, I got a flashing “TIT” high-temperature warning coming from the right engine JPI monitor, as the TIT had reached 1696 degrees (later determined, through engine monitor download, to have resulted from an uncommanded 3.5 GPH increase in the right engine fuel flow). Not only was the TIT about 250 degrees hotter than the left engine, but every right-engine cylinder’s EGT was considerably hotter than the left engine. Since the plane was light and the air was cold, I was climbing well to traffic pattern altitude, so I decided I had extra performance available to pull the power back a little bit to bring the temperature down on the right engine, but that did not do much of anything. I decided to discontinue the flight because I know my airplane well enough to know that those temperatures were not normal.
About on crosswind, and approaching traffic pattern altitude, the right engine and propeller felt like it was surging once in response to a power change, though I wasn’t touching any engine controls. A few seconds later, as I was turning to the downwind, all power was lost in the right engine. It was surreal: you feel an emergency should only happen on a “dark and stormy night” in icing with a plane full of passengers who are rushing into Aspen, or something. That you’re thrust into a situation where you’re on a peaceful flight, but now suddenly struggling all by yourself, can’t be explained. It definitely had a, “Uhh, okay, so this is really happening?” feel. It took many seconds to snap out of the mindset of, “Okay, plane. You’re joking. Come on. It’s ME, you’re owner here! I know you don’t act like this!”
I forced myself to go through the drill of “mixtures props throttles flaps-up gear-up identify verify,” but that did nothing since everything is where it already should have been. When I got to the step of “troubleshoot or feather,” I made an interesting decision (pay attention to this part): I decided to touch nothing until after I landed. I wasn’t on fire, and I didn’t need to feather the prop for performance. I was petrified of shutting down the wrong engine, or doing something that would somehow make the problem worse. And maybe the engine could come back? For at least a little bit of thrust? I continued the traffic pattern single-engine and landed somewhat uneventfully, though with great excitement. Upon opening all of the engine cowlings, no obvious engine damage showed. The engine remained “intact,” and did not shed parts, self-destruct, explode, or catch on fire, that I am aware.
After some investigation (that was only completed recently), the cause of the failure was determined: when the main fuel line comes into the fuel flow divider (or, “spider”), there are 6 nozzles that go to the 6 cylinders. Then there is the vent to the atmosphere. But there is also, what they apparently call in the industry, the “7th nozzle,” which is the line that goes back to the cockpit fuel flow gauge. When that line traversed the firewall, the connection had come loose. Very loose. Wasn’t even finger tight. When that line is loose, then it has the effect of sort-of “depressurizing” the spider, and can result in erratic fuel flows, up to a condition where the solenoid closes entirely, starving the engine of fuel. The mechanic who discovered this said that when he teaches his new mechanics, he even demonstrates that disconnecting that exact connection will kill an engine. The high EGT/TIT on takeoff was therefore correct: the engine was basically running lean because of the de-pressurizing spider. The engine surge later then, also made sense: the engine was running out of fuel. This was all discovered during troubleshooting, when the cowlings were off, by turning on the standby electric fuel pump (used only in an emergency in the Seneca), and when that was turned on, fuel sprayed everywhere, out of the loose connection coming from the 7th nozzle.
Going back to the actual event: had I decided to troubleshoot in-flight by trying the electric boost pump (which would have been a reasonable decision), it would have sprayed fuel everywhere and probably started a fire. It was probably a life-saving decision that I decided not to touch anything, and just let it windmill to the ground. It probably stemmed from my simulator training: no instructor ever tells you to go faster during an emergency; they always tell you go to slower. The saying in the sim is frequently stated as, “Enjoy the emergency.”
If I were in a Continental-powered single, I would probably would have tried the boost pump for sure, because you’re obviously more desperate. In a single, I would have either been doomed to an off-airport landing (if I didn’t try it), or doomed to a fire (if I did). I feel obligated to say at this point that twins are safer than singles, hands down. Period. Paragraph.
The fortunate element in success here, I feel, was that I was as well prepared as I could be for the event. I don’t mean to pat myself on the back, but just speaking factually: I am a former 17-year captain at a regional airline, and I am now a corporate jet captain, with about 12,000 hours of flight time. I recently finished my recurrent simulator training, and I had added a Hawker type rating last year. I have therefore done a significant amount of recent real-world flying as well as simulator emergency training. Additionally, in this incident I was flying my own aircraft out of my home base, at light weight with no significant terrain or weather on a cold morning. I had slept well, felt rested and healthy, and was not in a rush. The engines were already warm, and I had a lot of fuel on-board. It was daylight. I feel like all of these factors that I just listed all added “solid cheese” to the “Swiss cheese” model of accident causes, putting enough blockers in the way to prevent this from easily being able to have ended in an accident.
The shocking element in this is that the airplane only has about 100 hours since a major maintenance project was conducted on the airplane, soon after I bought it, where we conducted “firewall-forward” overhauls on both engines, propellers, mounts, hoses, accessories . . . everything. Additionally, just 5 flights prior to this, the airplane came out of an annual. Unfortunately, it sort-of proves Mike Busch’s theory of “maintenance-induced failure” as being more hazardous than to just let high-time engines run. But that’s a debate for another thread.
In the end, the fix was easy: 4 turns of a wrench and the problem was solved, and she has flown great since. I’m not sure if that gives me a warm and fuzzy feeling, though, for the mechanic then told me, “Don’t worry – every airplane you ever ride on – even airliners -- are just 4 turns of a wrench away from an engine failure, or some other major problem.”
I guess that is the risk we take every time we go up. We must be very trustworthy people in general. Or crazy. Or maybe both.
After this incident, I have learned my lesson: I have changed my mindset now, in that I view the maintenance shop as another thing in aviation that is constantly trying to kill me. Instead of blind trust, I now see myself as the last line of defense in everything.
Fly safe everybody. And put a wrench on all your connections yourself from time-to-time.
