BA
Topic Author
Posts: 10133
Joined: Fri May 19, 2000 11:06 am

What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 11:09 am

Enlarge the photo below:

View Large View Medium
Click here for bigger photo!

Photo © Philipp Brumann


Look right underneath the Rolls-Royce Trent 772B. What is that small puff of smoke or steam coming out the bottom? I have never seen this before.

Any feedback would be greatly appreciated.

Regards
"Generosity is giving more than you can, and pride is taking less than you need." - Khalil Gibran
 
Q330
Posts: 1425
Joined: Sat Dec 13, 2003 5:30 pm

RE: What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 11:11 am

Looks like tire smoke to me. I don't think it's coming from the engine.

-Q
Long live the A330!
 
Q330
Posts: 1425
Joined: Sat Dec 13, 2003 5:30 pm

RE: What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 11:18 am

Oh, wait, it might not be on the runway!  Nuts If it's not, I have no idea what it is.

-Q

[Edited 2004-03-10 03:20:52]
Long live the A330!
 
AJ
Posts: 2295
Joined: Wed Nov 03, 1999 3:54 pm

RE: What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 11:21 am

Most likely steam from the oil breather.
 
srbmod
Posts: 15446
Joined: Tue Mar 20, 2001 1:32 pm

RE: What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 11:21 am

A Rolls-Rolls engine that smokes?  Wow! What a novel concept.
 
OPNLguy
Posts: 11191
Joined: Tue Jun 15, 1999 11:29 am

RE: What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 11:25 am

Ah, yes, the glorious days of airline steam...  Big grin

(Probably an oil breather....)

ALL views, opinions expressed are mine ONLY and are NOT representative of those shared by Southwest Airlines Co.
 
LHcapt2007
Posts: 227
Joined: Tue Mar 09, 2004 3:55 pm

RE: What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 11:30 am

Any possibility of the shifting hydraulic loads imposed from slats/flaps/landing gear contributing to the smoke? Steam from the oil breather sounds ligit, but was this pic on landing or TO(I know the reversers arent deployed but maybe just at touchdown or rollout if a landing, prob TO)?

LHcapt2007

[Edited 2004-03-10 03:32:27]
TNCM
 
BA
Topic Author
Posts: 10133
Joined: Fri May 19, 2000 11:06 am

RE: What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 11:35 am

Thanks for the feedback everyone!

LHcapt2007,

It's on a taxiway, it could have either landed and gotten of the runway and is taxiing now or it could be taxiing to the runway for take-off. It certainly can't be taking off on the taxiway.  Smile

Regards
"Generosity is giving more than you can, and pride is taking less than you need." - Khalil Gibran
 
LHcapt2007
Posts: 227
Joined: Tue Mar 09, 2004 3:55 pm

RE: What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 11:38 am

LOL shouldve looked at the BIG TAXIWAY LINE right under the nose gear... duh thanks!

cheers
TNCM
 
BR715-A1-30
Posts: 6525
Joined: Thu May 30, 2002 9:30 am

RE: What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 12:20 pm

That is the smoke from the Oil Breather Vent. A Common sight on BR715s too.
Puhdiddle
 
Q330
Posts: 1425
Joined: Sat Dec 13, 2003 5:30 pm

RE: What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 12:36 pm

LOL shouldve looked at the BIG TAXIWAY LINE right under the nose gear... duh thanks!

I should have noticed that too, before I made that first post. Of course, taxiway lines do start on the runway and then curve off where there is a runway exit, but the plane is probably on a taxiway.

-Q
Long live the A330!
 
broke
Posts: 1299
Joined: Wed Apr 24, 2002 8:04 pm

RE: What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 9:16 pm

On all jet engines there is some leakage of high pressure air past the seals at the bearings into the oil system. This usually occurs at the bearings that are in the high pressure compressor/high pressure turbine assembly. The oil breather allows this air to dump overboard and not pressurize the oil system. The air is vented through a fixed devise that centrifuges the oil out of the air so, usually, there is little or no loss of oil out of the breather.
What I believe you are looking at is the air coming out of the breather. The air is warm and in humid or cold areas you may see condensation forming in the exhaust. If the engine losing oil out of the breather, the color of the breather air will be darker and there is generally staining on the cowling at the exhaust port.
 
VC-10
Posts: 3546
Joined: Tue Oct 26, 1999 11:34 am

RE: What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 9:53 pm

On all jet engines there is some leakage of high pressure air past the seals at the bearings into the oil system

That's what keeps the oil in! The rotor bearings are in a sump which is basically a box with the rotor shaft passing through it. Oil jets spray oil on the bearings in the sump and higher pressure air is fed into another 'box' around the sump. This air leaks into the sump through the seals and so keep the oil in the sump.

Both the oil and the air is extracted from the sump through the scavenge oil pumps and the mixture eventually finds its way to the oil tank in which there is a de-airator. Once separated from the oil the air is vented to the gearbox and vents to atmosphere via the centrifugal oil breather that removes any remaining oil from the air. It is this oil/air vapour you see in the picture.

You generally see the vapour when an engine is accelerating or decelerating as the internal pressures are unbalanced at this time.
 
User avatar
HAWK21M
Posts: 29867
Joined: Fri Jan 05, 2001 10:05 pm

RE: What Is This Smoke Coming Out Of The Engine?

Wed Mar 10, 2004 11:18 pm

Looks like Air from the Breather.
regds
HAWK
I may not win often, but I damn well never lose!!! ;)

Who is online

Users browsing this forum: Baidu [Spider] and 8 guests