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sudden Winds
29th Nov 2009, 19:35
Hi folks, got 3 questions for you all.

1) Leading edge flaps transit situation, no roll encountered, only one leading edge device extended or in transit according to the led annunciator panel. According to checklist, max speed 300 kts (280 for turb) or .65 mach. Now in this scenario, asumming we decide to continue our flight, do we climb to a FL less than FL200 because of that leading edge device not completely faired, or can we go up higher?
My thought is that we can go higher than FL200 for 2 reasons, one is, the MEL doesnīt prohibit dispatch higher than FL200 in that situation and 2, if a mach number limitation is provided, itīs being considered that the pilot may elect a higher FL.

2) One pack fails after takeoff, we reset it with the checklist, nothing happens, do we go up higher than FL250 or stay below that altitude?

My decision would probably be to stay lower than normal cruising FLs of 350-370, but I wouldnīt stay as low as 250. FL300-310 seems like a good compromise between remaining relatively fuel efficient (5% more fuel at optimum minus 4000 ft) and cautious in case a dual pack failure develops. Also going up a bit higher allows the pack to cool down more rapidly for a trip reset.

3) Youīre conducting a partial gear up landing, in this case the nose wheel was the one that refused to come out of her cave. You prepare for evac, burn fuel, emergency ' declared, everyone's waiting. Now, upon touch down, directional control remains perfect, you come to a complete stop. Tower and ground personnel inform you that there's no fire at all. Do you evacuate? Do you evacuate in a slower manner so as to avoid injuries, do you deplane ? Do you not evacuate at all? I know the most conservative thing to do is to evac, but can be the other options considered in this particular scenario?

I am all eyes !!!

The Real Slim Shady
29th Nov 2009, 19:40
What I do, and all the 737 rated pilots do, is follow the procedures in the QRH: that way we are fireproof. ;)

repulo
29th Nov 2009, 20:06
1.
If the QRH doesnīt limit your alt, you can go higher. Your max alt will be limited by the gradually increasing Mach number when climbing with 300 kts. So just climb and watch your Mach and stay below the given limits. Continued flight will make only sence when on a short sector that takes you back to you favorite maint. facility. (again a 1000 other facts that will make you decide different, avaiton is unpredictable)

2.

You have no alt limit. Watch your cab alt indicator and decide. Lots of contributing factors there. I had a dispatched flight with one pack inop and went in FL 250 from Germany to HEGN. On the way back we had so nasty CB weather over the alps, that I climbed for a short time to FL340 to get above. Itīs always a bargain. If it happens enrout and you are high, if the second pack fails you will have a gradual loss of pressure since the out flow valve will close, so no need for hectic. Just watch the cab and diff press indicator and arrange your descent accordingly. There is no need to leave your cruising FL.

3.

Too many contributing factors, so donīt concentrate on one solution.
Take all available facts into your decision making process like:
How many pax, what country, how good is their english, can the tower see the A/C, whatīs the WX, is the fire brigade next to the A/C, who is my purser:{

Hope it helps

Repulo

The Real Slim Shady
29th Nov 2009, 21:12
Sudden, thanks for your very polite, and informative, PM. Nice chap.

I was under the impression that 220Kts was the LE limit?

Denti
29th Nov 2009, 21:37
Nah, as mentioned above 300kts (280 in turbulent air) or M 0.65 if you have only one single leading edge device out, otherwise its 230kts.

For the third case it really depends on the situation, but if you do not have any immediate danger a controlled disembarkation might be better than a full blown evacuation. If you had the time to burn off fuel, do all the checklists, prepare the cabin all ground services will be on high alert and standing by and seconds after touch down you will have the fire service at your aircraft assessing the situation from the outside.

sudden Winds
1st Dec 2009, 02:16
anybody else folks? thank you guys so far!

Capt Chambo
1st Dec 2009, 04:55
1) Leading edge flaps transit situation, no roll encountered, only one leading edge device extended or in transit according to the led annunciator panel. According to checklist, max speed 300 kts (280 for turb) or .65 mach. Now in this scenario, asumming we decide to continue our flight, do we climb to a FL less than FL200 because of that leading edge device not completely faired, or can we go up higher?
My thought is that we can go higher than FL200 for 2 reasons, one is, the MEL doesnīt prohibit dispatch higher than FL200 in that situation and 2, if a mach number limitation is provided, itīs being considered that the pilot may elect a higher FL.

I would have no hesitation in going higher, but remember that 300Kts becomes M.65 by about FL250. Once you become Mach limited you may only be able to operate at about FL 350. (Variable of course depending on a/c weights, temps, a/c CoG etc). Also at these lower levels, and lower speeds, you need to consider your fuel usage.

2) One pack fails after takeoff, we reset it with the checklist, nothing happens, do we go up higher than FL250 or stay below that altitude?

The FL250 restriction is a MEL (dispatch) limitation. Pack failure in flight is a QRH NNC and there is no altitude restriction. The relevant authorities have deemed it acceptable to continue all the way up to FL410 on one pack. I would have no particular qualms about climbing all the way up to FL410 on one pack. (But I may just get the QRH out to remind myself of the emergency descent procedure ;))

3) Youīre conducting a partial gear up landing, in this case the nose wheel was the one that refused to come out of her cave. You prepare for evac, burn fuel, emergency ' declared, everyone's waiting. Now, upon touch down, directional control remains perfect, you come to a complete stop. Tower and ground personnel inform you that there's no fire at all. Do you evacuate? Do you evacuate in a slower manner so as to avoid injuries, do you deplane ? Do you not evacuate at all? I know the most conservative thing to do is to evac, but can be the other options considered in this particular scenario?

In this scenario I see no need to evacuate. (By evacuate I presume you to mean people leaping out the aeroplane onto slides). The chances of someone injuring themselves is too high. Deplane, but on the runway or do you taxi off the runaway? Your call! :)

sudden Winds
2nd Dec 2009, 01:19
thanks cap, good post.