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View Full Version : B777 Overweight LND CHKLST--Help Pls


Hulabaloo
20th Oct 2009, 10:24
Hello all,

Would someone please clarify for me. Following an engine shut down (with the ACFT overweight for landing) eg Eng Svr damage/sep the checklist asks choose one....land flaps 20 or performance permitting land using flaps 30.

When looking at the overweight landing checlist it gives two options to choose from the first rules out a flap 30 landing and the second option requires both engines to be running.

How is it possible to get out of the overweight landing checklist and make a flap 30 landing single engine?

your thoughts would be most welcome

regards

Hulabaloo

ratarsedagain
20th Oct 2009, 10:41
Any particular reason why you want to do a F30 landing (unless it's a performance critical runway) when the aircraft will autoland quite happily with F20 (The recommended flap setting for a single engine approach/landing)?
In the overweight landing case, the checklist is quite specific that you use Flap 20 if you are over MLW and on one engine. There is no option in the checklist to land with F20 if you are over MLW with eng failure due to performance considerations in the event of a G/A.

Hulabaloo
20th Oct 2009, 10:51
Well yes....for instance it was a performance critical runway

Wizofoz
20th Oct 2009, 10:57
rats,

Flap 20 is not the "recomended" s/e landing flap on the 777- at least not by Boeing or the Carrier I work for (who happens to operate more 777s than anyone else).

It is optional flap 20 or 30. You can use flap 30 provided you can make the approach climb gradient. Are you saying the Eng Fail C/L prohibits flap 30 if over MLW, as mine most assuredly doesn't. Which operator are you with?

There has been a cultural bias towards using flap 20 in the Sim, but this has been recognised as negative training and is being changed.

You are unlikely to have any performance problems Flap 30 s/e in a return to landing situation. After all, you just took off from the same runway with sufficient performance to meet any obstacle clearence margins with a V1 cut, so you are not going to have any problems making the s/e climb gradient (I'm talking in general terms here, there will, of course, be exceptions.)

For the one and only s/e landing you are likely to make in you career, I for one would like the lowest Vref available. I'll risk the small chance that I'm going to have to go-around on this particular approach (if so, I'm having a REALLY bad day!!) and take the best landing performance I can get.

Hulabaloo,

Don't have the C/L in front of me, but I think you might be mis-interpreting. From memory the C/L gives the flap 30 option if you can make the approach climb gradient, which you can except in extreme cases.

I'll look it up and post a more definitive answer later.

ratarsedagain
20th Oct 2009, 11:22
Wiz,
We operate quite a few 777's too;)

I was quoting from the FCOM QRH:
"The recommended flap setting for landing is F20. F30 may be used if the landing distance available is critical & go around performance permits it"

F30 is permitted in the single engine case with the "performance permitting" caveat.

The overweight landing checklist however asks you to choose from:
-Landing gross weight is greater than landing climb limit weight or one engine is inoperative

-Landing gross weight is less than the landing climb limit weight andboth engines are running normally

Therefore the Boeing QRH directs you to use F20 if you are over max landing weight with engine inop.

Regards

Hulabaloo
20th Oct 2009, 11:48
Thats the crux of my question following an eng. shut down you are directed to land using flap 20 or performance permitting flap 30...........in the over weight scenario completing the O/W checklist does not permit Flap 30 single engine..... but what happens if you need to carry out a flap 30 landing?

Do you over ride the check list?

I think it should direct you to the landing climb limit weight for a flap 30 single engine landing which following a eng shut down its checklist asks....performance permitting land Flap 30?

FullWings
20th Oct 2009, 18:51
Thats the crux of my question following an eng. shut down you are directed to land using flap 20 or performance permitting flap 30
Yes, but if you were planning on landing overweight as well then you'd go into that (unannunciated) checklist which would put you back to F20.
in the over weight scenario completing the O/W checklist does not permit Flap 30 single engine..... but what happens if you need to carry out a flap 30 landing?

Do you over ride the check list?
If the 13kts increase in Vref is going to make the difference between stopping on the tarmac and going cross-country, then I think you've answered your own question. To be put in this position your chosen runway must be very short and/or heavily contaminated... To be landing overweight on a poxy little strip you must have some sort of nasty time-critical emergency on the go as well: it's not your day - make up your own rules! :ok:

Wizofoz
20th Oct 2009, 23:47
rats,

Just goes to show different operaters have different "Standard Boeing" procedures!!

There is no recomendation in our FCOM, QRH or FCTM regarding F20 v F30 S/E, just the choice, with the "Performance permitting" caveat.

Yoy are quite correct regarding the Overweight C/L and this seems to answer Hullaballoos question, not withstanding Fullwings excellent advice above. I find it odd, however, that as MLW is a Structural limit, the c/l should use it as a dividing line for performance considerations.

You are, after all, not guarenteed to make climb gradient at weights below MLW, but depending on altitude/temp/varient will very often easily make them at weights considerably in excess of MLW.

Still, that's what the book sayeth...

Intruder
21st Oct 2009, 02:50
Thats the crux of my question following an eng. shut down you are directed to land using flap 20 or performance permitting flap 30...........in the over weight scenario completing the O/W checklist does not permit Flap 30 single engine..... but what happens if you need to carry out a flap 30 landing?

Do you over ride the check list?

I think it should direct you to the landing climb limit weight for a flap 30 single engine landing which following a eng shut down its checklist asks....performance permitting land Flap 30?
Doesn't the CAA have a rule equivalent to the FAA's 91.3(b) or 121.557(a)?
In an in-flight emergency requiring immediate action, the pilot in command may deviate from any rule of this part to the extent required to meet that emergency.


In an emergency situation that requires immediate decision and action the pilot in command may take any action that he considers necessary under the circumstances. In such a case he may deviate from prescribed operations procedures and methods, weather minimums, and this chapter, to the extent required in the interests of safety.

Are you going to run off the end of the runway? Are you able to use your head?

Busserday
21st Oct 2009, 07:24
In delving into this case, I am in a bit of a quandary regarding the "Landing Climb Limit Weight" charts in my company 777 QRH and am wondering if anyone else has the same situation.

It is my understanding that Approach Climb is OEI, etc. and Landing Climb is both engines operative, etc. and the less restrictive chart may not be published.

I have two charts under the above title, one which is further labeled "Valid for approach with flaps 20 and landing with flap 30" and the other with less restrictive data (as I would expect) labeled "Valid for approach with flaps 20 and landing with flap 25".

Are these charts the same as what you other chaps have and it seems to me that I need a chart labeled "Valid for approach with flap 30 and landing flap 30" to determine if I can use flap 30 for OEI as directed by the "Performance Permitting" remark in the ENG FAIL L,R checklist.

Cheerio,
BD

john_tullamarine
21st Oct 2009, 23:54
Busserday, putting emergency situations to one side, if you are going to schedule a configuration, you will need to address all the normal certification requirements.

I can't speak to the detail of charts I haven't seen. However, expect that any scheduled sequence will have data which addresses both the approach and landing climb requirements.

Busserday
22nd Oct 2009, 03:06
Hi John,
That is my point, I don't see where I can get approach climb limitations for flap 30 OEI with the lack of data given, yet flaps 30 is listed in the Engine Fail L,R checklist with the proviso of performance permitting and also referenced in the advisory Information Non-Normal Configuration Landing Distance/Engine Shutdown (Flaps 30).
Seems that my company QRH is missing something or I am missing something.

john_tullamarine
22nd Oct 2009, 03:13
There should be a simple answer although I can't identify it without any specific 777 data. OS will probably see this thread and should be able to comment seeing he drives the bird for the purposes of putting food on the kitchen table.

However, suggest that you contact your Tech Services folk, in particular the performance/operations engineering group and ask the question. They should have the specific answers and, I would hope, should be only too happy to walk you through the maze.

Busserday
22nd Oct 2009, 05:32
Thanks John,
Prepping for my first sim after intial qual. on type in June and will definitely be discussing this with the tech. ops. to get this sorted.
Previously I had defaulted to flap 20 for OEI and this issue had not surfaced, as that seemed to be the "cultural" bias for the situation.

BD