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dantealighieri
22nd Nov 2014, 12:45
please....some body knows where the official written doc is located concerning the engine warm up time before take off b 737 ?

IFixPlanes
22nd Nov 2014, 13:08
FCOM "Before Takeoff Procedure"

Johnny F@rt Pants
22nd Nov 2014, 16:07
Which is where you would expect to find it:ugh:

IFixPlanes
22nd Nov 2014, 16:43
No, where i find it:
FCOM B737
(http://www.directupload.net/file/u/51580/jj478xzg_jpg.htm)

dantealighieri
22nd Nov 2014, 17:26
could it be the same warm up time for all jets?

tubby linton
22nd Nov 2014, 17:37
CFM and IAE have different warm up times, it depends upon the time interval from previous use.

4Screwaircrew
22nd Nov 2014, 20:45
I was at a presentation given by a rep from CFM some years ago who said that in an ideal world they would like to see their engines run for 10 minutes prior to setting take off thrust. He maintained that this would be of great benefit to the engines longevity.

tubby linton
22nd Nov 2014, 20:51
Ten minutes, really? the CFM is almost indestructible in comparison to the IAE which we have to baby.

Amadis of Gaul
22nd Nov 2014, 21:22
I've heard GE people say the same thing about the CF34 a couple of airlines back.

tdracer
22nd Nov 2014, 23:02
SOP on the Boeing flightline is 5 minutes after a 'cold' start before advancing to high power. Doesn't matter what engine type.

Skyjob
23rd Nov 2014, 23:11
Shame many operators omit this SOP from their own manuals

plhought
24th Nov 2014, 08:12
The warm up prior to take off power on 146/RJs with ALF502/507 is three minutes.

If the engine has been shut down for less that 30 mins then no warm-up required.

Not really Boeing related but if those temperamental engines can be okay after three min I'm sure the CFM's on the Boeings are good...hahaha

lomapaseo
24th Nov 2014, 15:09
No need to judge good or bad about engines and warm ups.

As the efficiency of the engine designs improved over 50 years, the clearances over the blade tips needed to get tighter. Unfortunately differences in thermal expansions between parts works to defeat the exactness of this clearance either too little and it rubs causing permanent wear. While too much and the efficiency and/or stability goes to hell.

Be kind to your engine and follow the instructions that came with it :)

barit1
24th Nov 2014, 21:09
The "bowed rotor" phenomenon is discussed on the last half of this thread (http://www.pprune.org/tech-log/359845-turbine-starting-hot-starts.html).

Amadis of Gaul
24th Nov 2014, 22:34
The 146 has no engines, only 5 APUs. Would have had 7, if there was the room.

RAT 5
25th Nov 2014, 09:28
146 has no engines, only 5 APUs. Would have had 7, if there was the room.

The old joke are still the best; Ha ha: it must be the way ya tell 'em. Hee hee!

plhought
27th Nov 2014, 07:28
1 Airplane
4 Engines
6 Required


Ohh I havnt had a 146 joke-fest in a while :p

misd-agin
27th Nov 2014, 13:24
When in doubt five minutes works for most modern engines.

tdracer
28th Nov 2014, 04:18
There is hurting the engine, and there is HURTING the engine. On the Boeing flight line, the engines are brand new and the focus is minimizing any deterioration before we hand over to the customer. 5 minutes is pretty good for that. Making sure the engine doesn't surge or do something similarly unpleasant is different and is more engine dependent.