polaris
Pre-takeoff checklist
- Joined
- Oct 6, 2013
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- 132
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polaris
I got in a DA20 at my flight school yesterday and saw a note that I need to make sure to lean the mixture "a good distance back" during ground operations. I found it strange that it said "three full twists on the mixture," considering that the DA20's mixture lever does not involve turning anything. I suspected it must have been a blanket message to all aircraft in the fleet (most are Cessnas). But since I was not certain, I interpreted the message to mean something along the lines of: "This particular plane has been having problems with inadequate leaning by pilots. Please lean more than you usually would." I thought maybe the mixture lever was mis-calibrated so that I would need to lean farther than I am used to. Anyway, heeding the advice of the note, I made sure to lean pretty far back during my taxi. The engine ran fine, so I decided that it was properly leaned.
But about three minutes later, while I was taxiing to the runway, the engine suddenly stopped. (My girlfriend on board was not pleased.) I figured I must have leaned too far back (try explaining this to your girlfriend) and restarted the engine. It was still unsettling; why did it take so long for the engine to stop? If I had leaned too much, wouldn't I hear the engine sputter as a warning sign before completely seizing? Why would it keep running for three whole minutes and then stop?
After I restarted the engine, I resumed my taxi, but this time I leaned the mixture only about 3/4 inch. I knew leaning 3/4 inch wouldn't do much for ground ops because I know you need to lean pretty far back for it to do much of anything. But whatever. I kept taxiing, but this time, in about 30 seconds, the engine stopped again. At this point, I decided to turn back and call it a day.
When I returned to the flight school, the dispatcher (who is not a pilot) called maintenance. I was asked whether I had the fuel pump on. I am positive I had the fuel pump on during the initial taxi (I remember it; it's on the checklist). But I am not sure if I had it on during my second taxi attempt. I may have inadvertently turned it off in my rush and confusion to restart the engine (I was stalled in the middle of two intersecting taxiways at a busy controlled airport). I am not sure about this.
The fuel pump is REQUIRED during ground ops in the DA20. But I was not aware that if I did not have the fuel pump on, my engine would seize within 30 seconds. I have flown a lot of Pipers before, and they require fuel pump during ground ops. I've accidentally left the fuel pump off during ground ops and the engine did not seize 30 seconds into my taxi.
Do this all seem consistent with my failure to lean the mixture properly and my failure to turn on the fuel pump the second time around?
I am an instrument/commercial with about 300 hours in Cessnas, 200 hours in Pipers, and 50 miscellaneous -- and I have never run into any of these problems before. That is why I am confused and would like some clarification. Thanks in advance.
But about three minutes later, while I was taxiing to the runway, the engine suddenly stopped. (My girlfriend on board was not pleased.) I figured I must have leaned too far back (try explaining this to your girlfriend) and restarted the engine. It was still unsettling; why did it take so long for the engine to stop? If I had leaned too much, wouldn't I hear the engine sputter as a warning sign before completely seizing? Why would it keep running for three whole minutes and then stop?
After I restarted the engine, I resumed my taxi, but this time I leaned the mixture only about 3/4 inch. I knew leaning 3/4 inch wouldn't do much for ground ops because I know you need to lean pretty far back for it to do much of anything. But whatever. I kept taxiing, but this time, in about 30 seconds, the engine stopped again. At this point, I decided to turn back and call it a day.
When I returned to the flight school, the dispatcher (who is not a pilot) called maintenance. I was asked whether I had the fuel pump on. I am positive I had the fuel pump on during the initial taxi (I remember it; it's on the checklist). But I am not sure if I had it on during my second taxi attempt. I may have inadvertently turned it off in my rush and confusion to restart the engine (I was stalled in the middle of two intersecting taxiways at a busy controlled airport). I am not sure about this.
The fuel pump is REQUIRED during ground ops in the DA20. But I was not aware that if I did not have the fuel pump on, my engine would seize within 30 seconds. I have flown a lot of Pipers before, and they require fuel pump during ground ops. I've accidentally left the fuel pump off during ground ops and the engine did not seize 30 seconds into my taxi.
Do this all seem consistent with my failure to lean the mixture properly and my failure to turn on the fuel pump the second time around?
I am an instrument/commercial with about 300 hours in Cessnas, 200 hours in Pipers, and 50 miscellaneous -- and I have never run into any of these problems before. That is why I am confused and would like some clarification. Thanks in advance.