Sponsor Message:
Aviation Technical / Operations Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
How Stable Is The MD-11 On 2 Engines?  
User currently offlineNightFlier From United States of America, joined May 2004, 284 posts, RR: 2
Posted (10 years 5 months 1 week 6 days 6 hours ago) and read 8097 times:

I was watching a program on television one day and saw a pilot doing a demonstration with a Falcon 50, were he brought the # 1 engine to idle to simulate an engine failure. When he did this the airplane did not appear to be effected by the idling engine and the pilot explained how well the airplane handled on just 2 engines and how the effects of the #1 engine were not even felt by the passenger's and crew. So I was wondering even though the MD-11 has the #1 and #3 engines mounted below the wings, would it react similar to the Falcon if the MD-11 lost the #1 or #3 engine at any part of the flight ?


Airplanes are only as good as the people who fly&fix them.
19 replies: All unread, jump to last
 
User currently offlineNosedive From , joined Dec 1969, posts, RR:
Reply 1, posted (10 years 5 months 1 week 6 days 5 hours ago) and read 8018 times:

Well, I do know my dad had a bat go through his #1, when he landed the mech pointed to the fleshy stuff in the engine, coming out of Subic Bay. He said it felt more like the nose gear wasn't coming up quickly, and that the aircraft dragged a tad. So I guess the MD11 performs decent enough when it loses power to #1 or #3. I'll ask him for some more details later on.

User currently offlineCubsrule From United States of America, joined May 2004, 23294 posts, RR: 20
Reply 2, posted (10 years 5 months 1 week 6 days 5 hours ago) and read 8001 times:

From a merely qualitative point of view, I would imagine the MD-11 would be harder to control with no #1 or #3 engine because the thrust from the 2 working engines would be much further from being symmetric than that of the Falcon 50. I've been out of school for nearly 2 months and am thus far too lazy to do any calculations to give you a better idea of how severe the effect would be.


I can't decide whether I miss the tulip or the bowling shoe more
User currently offlineRiffedAAMech From United States of America, joined Jun 2004, 52 posts, RR: 0
Reply 3, posted (10 years 5 months 1 week 5 days 17 hours ago) and read 7593 times:

When I worked at McDonnel Douglas on the MD-11, we would always hear that the cargo carriers who used the MD-11 would shut down the #2 engine in flight to maximize fuel economy. Never verified if this was accepted operating procedure but it did sound like it was possible.

User currently offlineMD11Engineer From Germany, joined Oct 2003, 14137 posts, RR: 62
Reply 4, posted (10 years 5 months 1 week 5 days 17 hours ago) and read 7585 times:

AAMech,

No, you wouldn´t want to shut down an engine in flight without an emergency. Prolonged windmilling will damage the engine due to bad lubrication (You don´t have the internal bleed air to keep the bearing chambers sealed while windmilling). There is even a windmilling inspection in the AMM.
Throttle back, yes, but not shut down.

Jan


User currently offlineFDXmech From United States of America, joined Mar 2000, 3251 posts, RR: 34
Reply 5, posted (10 years 5 months 1 week 5 days 17 hours ago) and read 7567 times:

In addition, you would have to drift down to a lower altitude.

Reading the engine parameters on ACARS pretty much everyday, I've never seen this done. I suspect the flight crew would have to answer to his chief pilot, FAA, etc on violating established procedures.

I suspect this, urban legend.



You're only as good as your last departure.
User currently offlineNightFlyer From United States of America, joined Sep 2001, 95 posts, RR: 3
Reply 6, posted (10 years 5 months 1 week 4 days 15 hours ago) and read 7362 times:

Well, I've only flown it with the engines failed (1 and 2 engines at a time) in the simulator. It yaws a little more than the EMB145 that I used to fly but throw in a little rudder trim and you're good to go.

We don't shut the #2 engine down in flight to save fuel, we don't even shut one down for taxiing.


NightFlyer


User currently offlineMidnightMike From United States of America, joined Mar 2003, 2892 posts, RR: 14
Reply 7, posted (10 years 5 months 1 week 4 days 9 hours ago) and read 7284 times:

I would imagine that it will be very stable, all aircraft goes through a rigorous testing process. Then MD11 would have been tested with the #1 engine shutdown, #2 engine shutdown, #3 engine shut down, #1 & #3 engine shutdown, and so on.

All of this data is recorded and evaluated by the FAA, data is then gone over by the eningeers, and then this data is then uploaded into the databanks when they start building the full flight simulators.

Take for example the A380, they would perform months & months of inflight testing, shutting down the engines in every possible combinations, nothing is left to surprise.



NO URLS in signature
User currently offlineNightFlier From United States of America, joined May 2004, 284 posts, RR: 2
Reply 8, posted (10 years 5 months 1 week 3 days 6 hours ago) and read 7012 times:

Sounds good to me thanks for the help every one.  Big thumbs up


NightFlier



Airplanes are only as good as the people who fly&fix them.
User currently offlineAmericanAirFan From United States of America, joined Jun 2004, 408 posts, RR: 3
Reply 9, posted (10 years 5 months 1 week 2 days 8 hours ago) and read 6835 times:

Well I read a story about a Delta Airlines Flight 1141 August 1988 and they had up to an hour of taxi delays at DFW and requested to shut of # 2 engine and give thema 2 minute warning before takeoff to start the engine.(that was the Delta flight that crashed due to wrong fuel loads)
_Justin



"American 1881 Cleared For Takeoff One Seven Left"
User currently offlineNightFlyer From United States of America, joined Sep 2001, 95 posts, RR: 3
Reply 10, posted (10 years 5 months 1 week 2 days 7 hours ago) and read 6824 times:

AmericanAirFan,
If you're refering to the Delta 727 that crashed at DFW, it crashed because they forgot to set the flaps for takeoff.


NightFlyer


User currently offlineAmericanAirFan From United States of America, joined Jun 2004, 408 posts, RR: 3
Reply 11, posted (10 years 5 months 1 week 2 days 5 hours ago) and read 6794 times:

I got the story from a book called the black box and they hav all the transmitions and stements of the flight and there was a fuel gauage that did not work and the tanks were not filled equaly if you have a webpage to back it up prove me wrong Im not saying im right
_Justin



"American 1881 Cleared For Takeoff One Seven Left"
User currently offlineNightFlyer From United States of America, joined Sep 2001, 95 posts, RR: 3
Reply 12, posted (10 years 5 months 1 week 1 day 9 hours ago) and read 6618 times:

Here ya go: http://www.ntsb.gov/ntsb/brief.asp?ev_id=20001213X26528&key=1


NightFlyer


User currently onlineCrosswind From United Kingdom, joined Nov 2000, 2602 posts, RR: 58
Reply 13, posted (10 years 5 months 6 days 20 hours ago) and read 6485 times:
Support Airliners.net - become a First Class Member!

I have heard that in the early 1970s some US carriers experimented with a procedure to throttle back the #2 engine in the cruise, in order to try and save fuel, at the expense of a slower cruise speed. This was during the height of the fuel crisis when oil prices had risen sharply.

It was found to be counter-productive, as intake-drag from the #2 engine being throttled back prevented any increase in efficiency.

Regards
CROSSWIND


User currently offlineMD-90 From United States of America, joined Jan 2000, 8508 posts, RR: 12
Reply 14, posted (10 years 4 months 4 weeks 1 day 5 hours ago) and read 6263 times:

The 727 with the incorrect flap settings (basically, no flaps) was a Northwest aircraft, I believe.

I think that the 727 would be a better example to compare with a Falcon than the MD-11.


User currently offlineNightFlyer From United States of America, joined Sep 2001, 95 posts, RR: 3
Reply 15, posted (10 years 4 months 4 weeks 6 hours ago) and read 6210 times:

MD-90,
I believe you're thinking of the NW DC9 that crashed in Detroit.

NightFlyer


User currently offlineFreshlove1 From , joined Dec 1969, posts, RR:
Reply 16, posted (10 years 4 months 4 weeks 6 hours ago) and read 6206 times:

I never recall a DL flight crashing in AUG of 88' due to incorrect fuel loads. I do recall a DL flight crashing in DFW due to the flaps not being set correctly because the crew was to busy joking with the F/A's during the taxi. The NW flight was an MD-80 not a 727 and that did crash due to the flaps not being set.

User currently offlineMD-90 From United States of America, joined Jan 2000, 8508 posts, RR: 12
Reply 17, posted (10 years 4 months 3 weeks 6 days 3 hours ago) and read 6130 times:

DC-9, 727, same difference. Big grin

User currently offlineThrust From United States of America, joined Sep 2003, 2691 posts, RR: 10
Reply 18, posted (10 years 4 months 3 weeks 3 days 17 hours ago) and read 6033 times:

No matter how fuel-inefficient, you want to all the engines when flying an aircraft...I certainly would...you can fly faster...you are safer...and it is dangerous flying without one of your engines. I would certainly feel uncomfortable, don't know 'bout any of you daredevils though  Laugh out loud


Fly one thing; Fly it well
User currently offlineThrust From United States of America, joined Sep 2003, 2691 posts, RR: 10
Reply 19, posted (10 years 4 months 3 weeks 3 days 17 hours ago) and read 6046 times:

No matter how fuel-inefficient, you want to use all the engines when flying an aircraft...I certainly would...you can fly faster...you are safer...and it is dangerous flying without one of your engines. I would certainly feel uncomfortable, don't know 'bout any of you daredevils though  Laugh out loud


Fly one thing; Fly it well
Top Of Page
Forum Index

Reply To This Topic How Stable Is The MD-11 On 2 Engines?
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...
How Safe Is An MD-11 On A Scale Of 1-10 posted Tue Nov 5 2002 01:29:00 by Apollo13
Why Is The MD-11 Engine Tipped Up? posted Mon Jun 14 2004 20:31:38 by FrontierCPT
GE Engines On The MD-11 posted Fri May 10 2002 16:22:04 by N79969
Elevators On The MD-11 posted Fri Mar 3 2006 12:45:42 by Jeffry747
How Big Are The Overhead Bins On The E-Jets posted Thu Jul 6 2006 02:17:23 by Tangowhisky
Where Is The Trim Wheel On A380? posted Sat Nov 12 2005 16:02:47 by Keta
What Is The Errant Wire On This CO 757? Photo posted Tue Jun 7 2005 04:14:34 by FlyingTexan
Why Do Cargo Airlines Like The MD-11 So Much? posted Sun Mar 7 2004 12:09:49 by Mozart
How Much Is The Seperation posted Thu Feb 12 2004 12:31:36 by HAWK21M
How Hot Do The Breaks Get On The 747... posted Tue Apr 24 2001 22:27:17 by Tuffty

Sponsor Message:
Printer friendly format