deltajet757
Posts: 228
Joined: Sat Sep 16, 2006 1:26 pm

Engine Smoke Question

Mon Feb 05, 2007 2:19 pm

I was browsing through a bunch of NW 744 pics and videos recently and as I was watching a video of a NW 744 taking off to NRT from DTW I saw a lot of black smoke coming out of it's engines.

http://www.flightlevel350.com/aviation_video.php?id=7832&s=y

Is it common for the PW4000 engines to do that or are they in need of a coke wash? Perhaps both?

I also came upon a photo of a UA 744 departing SYD with a little bit of smoke noticably coming off engines 3 & 4 (1 & 2 if you look closely enough)


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Photo © Jackson Qiu



-DeltaJet757
FLY DELTA JETS
 
RandyWaldron
Posts: 215
Joined: Tue Mar 21, 2006 9:40 am

RE: Engine Smoke Question

Mon Feb 05, 2007 4:14 pm

Quoting DeltaJet757 (Thread starter):
I saw a lot of black smoke coming out of it's engines.

It's all about perception. Yes, you observed exhaust gases, but there is nothing overly exciting about them. Current weather conditions also contribute to the appearance of exhaust gases...No, the engines are not in need of a washup, and no, that was not "a lot" of black smoke.

[Edited 2007-02-05 08:16:15]
"Flaps 20, gear down, landing checklist please..."
 
deltajet757
Posts: 228
Joined: Sat Sep 16, 2006 1:26 pm

RE: Engine Smoke Question

Tue Feb 06, 2007 11:48 am

Really? I never would have thought of that.

-DeltaJet757
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EMBQA
Posts: 7797
Joined: Sat Oct 25, 2003 3:52 am

RE: Engine Smoke Question

Tue Feb 06, 2007 11:59 am

ALL engines smoke.... some more then others. It is most notiable during take off as the engine is under its biggest load. 'Coke washing' will do nothing for a smokey engine. Coke washing is done only to remove build up of material... most likely carbons...from inside the engine. It is also done rarely as it will reduce the life of the engine. Compressor washes are more common and done on a schedules basis. Compressor washing is the application of a water based 'degreaser' to the internals of the engine. It helps remove the build ups from inside the engine, but is far less agressive then coke cleaning.

If you want to see smokey engines, just look at some of the pices from the 1960's...!!

[Edited 2007-02-06 04:00:49]
"It's not the size of the dog in the fight, but the size of the fight in the dog"