Low indicated airspeed. Acting like a piston?
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Flying to the Arctic Ocean today and at 38,000ft I am getting an IAS of 137 and a TAS of less than 200. Also, at that altitude, the engines were losing power, my torq was at 52 and if I tried to get it back to 90/1600, the ITT would go red. What am I doing wrong? I figured these PT6As wouldn’t act like a piston at this altitude.
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Flying to the Arctic Ocean today and at 38,000ft I am getting an IAS of 137 and a TAS of less than 200. Also, at that altitude, the engines were losing power, my torq was at 52 and if I tried to get it back to 90/1600, the ITT would go red. What am I doing wrong? I figured these PT6As wouldn’t act like a piston at this altitude.
@dadgametime You can't do 90% torque at high altitudes. You will be limited by your ITT. At 37,000ft, you should have around 50% torque and 280 TAS. Your TAS is indeed low.
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Thats an IRL variable- especially during the summer, you will be ITT limited in most cases.
Just because the handle can go full forward, doesn't mean you should. Unlike jet engines, you can destroy an engine just by your hand. Back when I was flying Caravans, you spent most of the flight glued to that ITT gauge. It was the most important thing trying to "fly the engine"
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This is super helpful! Thank you! That’s what I’ve been doing, flying the ITT. So how far should I push it? Is it ok to run it just below redline or should I stay cooler to prolong the engine? I’ve found a POH, so I’ll check the charts, assuming it has some for cruise.
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This is super helpful! Thank you! That’s what I’ve been doing, flying the ITT. So how far should I push it? Is it ok to run it just below redline or should I stay cooler to prolong the engine? I’ve found a POH, so I’ll check the charts, assuming it has some for cruise.
@dadgametime there is a manual included with the aircraft that is very comprehensive.
Also includes power settings.
