PDA

View Full Version : Question: What is idle fuel flow (at ISA) for a PT6A-67 engine?


V1... Ooops
15th Dec 2009, 21:27
Hello All:

Does anyone know approximately (with accuracy within about 20 PPH) what idle fuel flow is on a PT6A-67 engine, assuming ISA conditions? I am primarily interested in governed idle fuel flow, however, if anyone happens to know what the 'minimum flow' value is (meaning, idling at minimum flow value, rather than idling on governed fuel), I would be most grateful for that figure as well.

I don't need to "bet the rent money" on these figures, I just need a reasonably accurate approximation to enable me to compare the value for the -67 (any variant) to the smaller PT6A engine series.

Many thanks in advance,

Michael

rigpiggy
16th Dec 2009, 01:05
If you mean the min flow valve with an fcu failure approx90pph @50% N1, otherwise around 210pph

V1... Ooops
16th Dec 2009, 03:27
Rigpiggy:

Thanks very much for that answer. 90 PPH at 50% Ng is pretty similar to idle fuel flow for the smaller PT6A series.

About the 210 PPH figure you give - approximately what Ng does that result in?

Cardinal
16th Dec 2009, 18:11
Normal Idle, 210pph, 65-67% N1.

Idle at FL250 can get down as low as 120pph.

As stated the Min Flow Adjustment is 90pph, which you only see at startup.

rigpiggy
16th Dec 2009, 18:20
or with a failure of p3air to the pneumatic bellows. MOR!!!!

V1... Ooops
16th Dec 2009, 21:51
Cardinal and Rigpiggy:

Thanks very much, between the two of you my question has been fully answered. Let me know if I can ever return the favour.

Michael