Reduced power takeoffs in an ATR?

[dwcaviator]

Does anyone out there know of any carriers that conduct reduced power takeoffs in the ATR? I know that every takeoff is reduced to roughly 90% -- the ATPCS will "uptrim" the good engine in event you lunch one on takeoff. I'm looking to find out if anybody takes the torque down further. If so, how so?

 

[dwcaviator]

Alright, let me ask this question. Do you fly ATR's and your company does not do reduced power takeoffs?

 

[OPECJet]

Torque could be 90, but Nh / Nl could be in the high 90s rendering a non-reduced power takeoff.

 

[A1FlyBoy]

uh.... deleted

 

[ehaecker]

I asked this same question in training. I was told that all takeoffs, more or less, are "reduced 'thrust'".

 

[dwcaviator]

I mistyped above. A typical sea level takeoff is conducted using about 91% torque, a number you get from performance tables. The target torque bugs set themelves to around 100%. In the event of an engine failure, uptrim boosts the torque on the good engine to around 100%. So the $64,000 question remains, are there any ATR operators out there who have an SOP to reduce torque even lower than the performance table value?

 

[Mike man]

reduce torque even lower than the performance table value?

Why would anyone reduce torque lower than the manufacturers performance table?

Let me see if I am getting this correct...

ATR operators get REDUCED takeoff performance from manufacturers performance table...you are asking if some operators REDUCE the REDUCED takeoff performance?

The correct answer to your question is...NO.

 

[dwcaviator]

My company operates ATR-42-320's--no notch, but thanks for the input. Our company is thinking of using less than the approx 90% takeoff power. I'm trying to find out if there are any ATR operators who do so.

 

[ultrarunner]

..So the $64,000 question remains, are there any ATR operators out there who have an SOP to reduce torque even lower than the performance table value?

How on earth could you flex below a minimum number set by the manufacture via an SOP????

 

[BobbyBiplane]

A number of operators have received approval to use the "Assumed Temperature" method of flex to a minimum of 80% maximum rated take-off power. A guy who used to work at Pan Am and later ATR first established and received approval to use this procedure back in Philadelphia in the 1980s.

Bob

 

[Brasilia Pup]

I thought the ATR was already at Reduced Torque. It sure flew slowly enough to feel like that. Kinda like the Brasilia was fuel critical the moment you pushed out of the gate.

 

[unwashed]

I did assumed temp TO with a Dash 8 100/200/400 all the time. I do them all the time now in a Jet. Not a big deal. Are they safe, hell yea they are. It saves the engines for when you might need them most, on a real emergence, not just taking off day to day.

 

[dwcaviator]

Assumed temperature is exactly what I was getting at. Interesting that the min flex was 80%. The performance tables I'm looking at would make as low as 75% possible, but I like that margin. Any current ATR operators out there do it?

 

[unwashed]

25% reduction is the maximum allowable under the FAA.

 

[BobbyBiplane]

The issue with ATRs at lower than 80% is that at certain atmospheric condiitions it is possible to have the assumed temp minimum power point at a PL angle where the ATPCS does not arm invaledating the entire process.

Bob