Sponsor Message:
Aviation Technical / Operations Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
Dirty Exhaust From Engines, Just Old?  
User currently offlinesmartt1982 From United Kingdom, joined Nov 2007, 225 posts, RR: 0
Posted (1 year 5 months 3 weeks 1 day 3 hours ago) and read 3782 times:

Anytime I see some of the older jets take off e.g. older MD 80 series etc. I notice a fiar amount of what I would describe as a very smokey oily exhaust trail.

Now I realise that the aircraft and engines are probably not the newest but is this just the way the engines are, even with the necessary and required maintenance these older engines will allows produce more a s smokey oily exhaust trail?

11 replies: All unread, jump to last
 
User currently offlinePolot From United States of America, joined Jul 2011, 2129 posts, RR: 1
Reply 1, posted (1 year 5 months 3 weeks 1 day 2 hours ago) and read 3766 times:

Quoting smartt1982 (Thread starter):
Now I realise that the aircraft and engines are probably not the newest but is this just the way the engines are, even with the necessary and required maintenance these older engines will allows produce more a s smokey oily exhaust trail?

Yes- because the smokey trails stem from design, not maintenance. They just don't burn as cleanly as newer engine designs, and no amount of maintenance can fix that.


User currently offlinercair1 From United States of America, joined Oct 2009, 1308 posts, RR: 52
Reply 2, posted (1 year 5 months 3 weeks 1 day 1 hour ago) and read 3738 times:
AIRLINERS.NET CREW
CUSTOMER SERVICE & SUPPORT

It is amazing how we have changed. I remember I used to like those trails - but now they look very dirty.


rcair1
User currently offlinesrbmod From , joined Dec 1969, posts, RR:
Reply 3, posted (1 year 5 months 3 weeks 1 day ago) and read 3687 times:

Quoting Polot (Reply 1):
Yes- because the smokey trails stem from design, not maintenance. They just don't burn as cleanly as newer engine designs, and no amount of maintenance can fix that.

Case in point:


View Large View Medium
Click here for bigger photo!

Photo © Charlie Atterbury



Early jet engines at times required water injection in order to product the needed thrust for takeoff. As technology improved, the need for water injection was lessened as engines were able to produce the necessary thrust without having to use water injection.

The MD-80s are really the last of the "smoky" airliners as the engine tech has improved even further. The engines on the MD-80 are updated versions of the same engine they used on the DC-9 as well as the 727 and the 737-100 and 737-200.


User currently offlineHAWK21M From India, joined Jan 2001, 31667 posts, RR: 56
Reply 4, posted (1 year 5 months 3 weeks 23 hours ago) and read 3666 times:

Amazing Improvement with regards to sound and pollution.
From the turbojet age to the low bybass turbofan to the current high bypass turbofan.



Think of the brighter side!
User currently offlinefuelfool From United States of America, joined Feb 2011, 138 posts, RR: 0
Reply 5, posted (1 year 5 months 3 weeks 20 hours ago) and read 3592 times:

Between the nasty exhaust of the huffer and the engines on the DC8, I used to feel like I could feel cancer cells forming in my body every time we fired one up.


I love the smell of jet fuel in the morning...Smells like victory!
User currently offlinejetstar From United States of America, joined May 2003, 1642 posts, RR: 10
Reply 6, posted (1 year 5 months 2 weeks 5 days 20 hours ago) and read 3081 times:
Support Airliners.net - become a First Class Member!

The black smoke you see coming from the exhaust of jet engines in carbon. One of the effects of these carbon particles was erosion of the turbine blades. The jet engine manufacturers redesigned the combustion chambers to burn up the carbon internally instead of it coming out of the exhaust and this basically eliminated exhaust blade erosion.

Many years ago when I was working on the turboprop Grumman Gulfstream 1, the RR Dart engines would build up a clump of carbon within the combustion chamber and when it grew large enough, it would let go and come out the exhaust pipe, you would see these on takeoff as a puff of black smoke. I believe the term RR used was clingers and it was causing erosion problems on the turbine blades, RR redesigned the combustion chamber and it solved the problem.

When I was flying the JetStar and ATC called out traffic and if the visibility was clear enough you could spot the airplane by the black smoke, especially if they were climbing out on takeoff.

It was in the late 1970’s or so when due to FAA, I believe under pressure from the EPA the engine manufacturers redesigned the combustion chambers and they had to be installed whenever the engine was overhauled.

JetStar


User currently offlineAaron747 From Japan, joined Aug 2003, 8032 posts, RR: 26
Reply 7, posted (1 year 5 months 2 weeks 5 days 14 hours ago) and read 2953 times:

Gotta love it. There just isn't enough smoke these days. For awhile longer we can enjoy these over on this side of the Pacific:


View Large View Medium
Click here for bigger photo!

Photo © Ryotaro Shinozaki




If you need someone to blame / throw a rock in the air / you'll hit someone guilty
User currently offlineBlueJuice From United States of America, joined Jun 2010, 242 posts, RR: 0
Reply 8, posted (1 year 5 months 2 weeks 4 days 11 hours ago) and read 2683 times:

Did someone say smoke?

http://www.youtube.com/watch?feature...er_detailpage&v=isP1LVVZ6nU#t=353s


User currently offlineKELPkid From United States of America, joined Nov 2005, 6346 posts, RR: 3
Reply 9, posted (1 year 5 months 2 weeks 4 days 11 hours ago) and read 2680 times:

Under certain conditions, the IAE V2500 gives off a little bit of smoke trail, guess it is the Pratt & Whitney heritage of the combustor showing through  


Celebrating the birth of KELPkidJR on August 5, 2009 :-)
User currently offlineLH707330 From United States of America, joined Jun 2012, 732 posts, RR: 0
Reply 10, posted (1 year 5 months 2 weeks 3 days 12 hours ago) and read 2368 times:

Quoting KELPkid (Reply 9):
Under certain conditions, the IAE V2500 gives off a little bit of smoke trail, guess it is the Pratt & Whitney heritage of the combustor showing through

Often that's due to dirt in the combustor, I've seen CFM56s and other new engines do this as well.


User currently offlinebhill From United States of America, joined Sep 2001, 954 posts, RR: 0
Reply 11, posted (1 year 5 months 2 weeks 2 days 23 hours ago) and read 2227 times:

Wow....wonder if pilots had to change regimes from VFR to IFR being behind a few of those birds after takeoff....  


Carpe Pices
Top Of Page
Forum Index

Reply To This Topic Dirty Exhaust From Engines, Just Old?
Username:
No username? Sign up now!
Password: 


Forgot Password? Be reminded.
Remember me on this computer (uses cookies)
  • Tech/Ops related posts only!
  • Not Tech/Ops related? Use the other forums
  • No adverts of any kind. This includes web pages.
  • No hostile language or criticizing of others.
  • Do not post copyright protected material.
  • Use relevant and describing topics.
  • Check if your post already been discussed.
  • Check your spelling!
  • DETAILED RULES
Add Images Add SmiliesPosting Help

Please check your spelling (press "Check Spelling" above)


Similar topics:More similar topics...
Airliner Crashes From Helo Wake Vortex.. OLD posted Mon Apr 23 2012 22:02:00 by HaveBlue
Modern Jetliner Exhaust - When Is It Too Dirty? posted Tue Nov 3 2009 22:00:30 by Reggaebird
What Is This "Smoke" From Under A340 Engines? posted Sat Aug 22 2009 04:30:22 by Ambanmba
"Wang" Noise On Take-off From Jet Engines posted Tue Sep 16 2008 20:16:06 by FlyASAGuy2005
Do Modern Piston Engines Have Flames In Exhaust? posted Sun Feb 18 2007 17:07:38 by N231YE
How RR Get So Much Power From Smaller Engines? posted Thu Aug 17 2006 04:43:49 by 747400sp
New Exhaust Standard For Airplane Engines posted Fri Apr 7 2006 16:06:24 by Azstagecoach
Why Do Old Jet-engines Smoke So Much? posted Sun Dec 25 2005 23:02:10 by TheSonntag
Jet Engines And "dirty" Runways posted Mon Apr 26 2004 21:05:53 by KjBersas
Lotsa Smoke Coming From ASA CRJ Engines posted Tue Sep 16 2003 02:13:39 by BR715-A1-30

Sponsor Message:
Printer friendly format