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AQ737Driver
14th Oct 2010, 10:42
Scenario:

You are flying an aircraft with no fuel dumping capability. You are taking off right at your MGTOW which is higher than your MLW. Your engine flames out at 400 feet and doesn't auto-relight (if you have that capability).

Runway length/terrain not an issue. Weather is VFR. You are going to be put in the hold about 15 miles away from the airport to sort things out.

Are you going to make an overweight landing? If so, why not burn off fuel? If not, why not?

We got into a discussion about this today, and I'm really curious to see other people's opinions... also which type of airplane you're flying, and what segment of the industry you're in.

hetfield
14th Oct 2010, 10:44
Your engine flames out at 400 feet How many engines does the aeroplane have?

reivilo
14th Oct 2010, 10:52
With a 'normal' engine failure, our company SOP advise us to make an overweight landing. No rush so we land after completing all the checks etc. in the holding near the airfield. Why land overweight? Because you've just lost redundancy, with just 1 operative engine remaining (B737). Same with all other faults/failures, for example if you've just got 1 hydraulic/electrical source remaining: land nearest suitable airport. Boeing has written this in the chapter 'Checklist introduction'.

Fliegen_Inlander
14th Oct 2010, 10:56
I guess my Bus could hold up to MTOW for its landing capabilities, so I my answers:

Troubleshoot, ( prefer to go to Holding area ), preparation that include the Overweight ldg Cx, approach, write the problem and Overweight Landing on Maintenance log book,

hetfield
14th Oct 2010, 11:02
Troubleshoot, ( prefer to go to Holding area ), preparation that include the Overweight ldg Cx, approach, write the problem and Overweight Landing on Maintenance log book

How many engines do you have F_I ?

Wizofoz
14th Oct 2010, 11:02
I doubt there is any operator of twin Boeing's anywhere that would advise anything other than to land overweight. It should even be considered in aircraft that DO have fuel jettison capability.

From my POV if the engine "Just flamed out" for no apparent reason, you have no way of knowing if whatever caused it to stop won't cause the other to do likewise.

MLW is simply a structural consideration. If you regularly landed over it, you would excessively stress the airframe and reduce it's life.

Do it rarely in emergency situations, and all that it will mean is an inspection before the aircraft flys again, so it's a no-brainier.

Wirbelsturm
14th Oct 2010, 11:07
Bus',

Turn the packs off (reduce demand on the remaining engine), select Flap 3 (reduce drag if the LDA allows) and land it. 319 is certified for overweight autoland (as it was demonstrated and certified by the Airbus test pilots), 320 + 321 needs CAT 1 conditions for overweight landing.

Not a problem.

Fliegen_Inlander
14th Oct 2010, 11:10
2, and no fuel dumping A320,

hetfield
14th Oct 2010, 11:16
Okay, my 2 cents

Troubleshoot, ( prefer to go to Holding area ), preparation that include the Overweight ldg Cx, approach, write the problem and Overweight Landing on Maintenance log bookTroble shoot ? Holding? Maintenance Log book?:=

Man, you are on single engine!

Declare Emergency! Try to stay overhead or near the airport (ATC) prepare for approach and get the dam thing down..

Fliegen_Inlander
14th Oct 2010, 11:42
ah yeah you are correct, of course emergency, and do the ECAM/ Emergency Cx/ and log book, obviously after landing, to mention that we've done Overweight landing

AQ737Driver
14th Oct 2010, 12:08
Hetfield, I should have mentioned - 2 engines.

hetfield
14th Oct 2010, 12:22
@AQ737Driver

Yeep, so please refer to my last post.

3 or 4 engines different situation, 'cause not time critical/less risk so no need to land overweight.

Exaviator
14th Oct 2010, 12:30
3 or 4 engines different situation, 'cause not time critical/less risk so no need to land overweight.

Regardless of its fuel dumping capabilities the B-747 is certified for overweight landing if conditions dictate an immediate landing.:ok:

hetfield
14th Oct 2010, 12:34
Yeah, most commercial planes are.

Herod
14th Oct 2010, 13:01
A thought about landing ASAP. Don't forget that the maintenance team who serviced the one that's just failed probably serviced the one you're relying on. The Queen's Flight 146 springs to mind. Don't rush things;you'll get it wrong, but get down fastish.

bcgallacher
14th Oct 2010, 13:48
From a maintenance point of view an overweight landing inspection is usually no big deal - an overweight heavy landing might cause a wrinkle or two but just because the landing is overweight there is no need to panic.

captjns
14th Oct 2010, 13:55
Part of the certification process is to demonstrate that the aircraft can land at it's intended MTOGW.

Anyway talk to maintrol and see what they want you to do. Long runway, cost of fuel, overweight landing? It's a non event event.

Done it on long runways a few times on the 727, and the breaks didn't sweat a bit. But then again, the thrust reverse on the 727 is much more effective than on the slugs of today.

TopBunk
14th Oct 2010, 16:17
Boeing Commercial Aeromagazine did an article a few years ago that some may find useful reading from a company that has some knowledge in the matter.

I won't cut and paste excerpts, as it is useful background reading.

http://www.boeing.com/commercial/aeromagazine/articles/qtr_3_07/AERO_Q307_article3.pdf

GlueBall
14th Oct 2010, 21:57
Don't forget that the maintenance team who serviced the one that's just failed probably serviced the one you're relying on.

I'm not an ETOPS driver, but can one clarify that on ETOPS missions the same maintenance person(s) may not service both engines . . . ? :confused:

Capt Turbo
14th Oct 2010, 23:52
There are two main considerations, if the situation warrants an overweight landing:
- Performance; LDA etc. and in case of a go around.
- Structural. All commercial (FAR/JAR 25) jets are certified with a certain max touchdown g-load equal to approximately 600`/min ROD at Maximum Landing Mass. This load is reduced linearly to approximately 200/min touchdown ROD at Maximum Takeoff Mass. There are a few exeptions ( e.g. upgraded A340s).

So unless you smash the heavy bird into the ground, the structure is capable of an overweight landing witout major problems. As a rule-of-thumb you can always land on the T/O runway with the same weight.

The decision to wait and burn off fuel or not lies with the risk of loosing a non-redundant system or being on a time critical system only:
- On batteries only: Land
- On fire: Land
- On one engine: Land
- Loss of cabin pressure: Wait
- Gear problems: Wait

So to answer the original question : Do not hurry, but land with the overweight since the conditions are favourable.
T

MurphyWasRight
15th Oct 2010, 16:59
Quote:
]3 or 4 engines different situation, 'cause not time critical/less risk so no need to land overweight.


Regardless of its fuel dumping capabilities the B-747 is certified for overweight landing if conditions dictate an immediate landing.


I seem to recall a certain British airline rather famously burning off fuel (all most) all the way home in the 747 single engine out scenario. :)

TopBunk
15th Oct 2010, 17:56
Murphy

and that adds what exactly to the debate:=

duelinput
15th Oct 2010, 18:36
JAR25 commercial jet certification :
- 600 fpm max at MLW
- 360 fpm max at MTOW