If dual eng. failure ditching had been a B737NG..what procedures would you consider?
If you are going to close the outflow valves manually, may I suggest turning off the packs or the bleeds FIRST. The evacuation procedure should go faster with the doors open.
I maybe an outlier, all else being equal, if given the choice, a water landing might be a better option that an off-airport landing. Off-airport landing spots will have some uneven terrrain, obstacles, all items that will cause the plane to "dig" and self-destruct. Look at the YYZ incident, while everyone got off, the airplane was in far worse shape and fire a major hazard. So, if given a lake or river or an open cornfield with trees, I'd take the water landing. Love to hear the counterarguments.
GF
I maybe an outlier, all else being equal, if given the choice, a water landing might be a better option that an off-airport landing. Off-airport landing spots will have some uneven terrrain, obstacles, all items that will cause the plane to "dig" and self-destruct. Look at the YYZ incident, while everyone got off, the airplane was in far worse shape and fire a major hazard. So, if given a lake or river or an open cornfield with trees, I'd take the water landing. Love to hear the counterarguments.
GF
ECON cruise, LR cruise...
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I agree, water beats NJ residential areas any day 
I think the best call the skipper made was declining the TEB option, despite ATC trying to be helpful. It looks might tempting from that position, but 24 is a bit short for a 320, and it's a long way around to final 01. I'd like to think that I'd have gone for the river as well
There but for the grace of God...
BTW, if both your engines are out (unless you're doing a engine bleeds off takeoff), the cabin should leak down very quickly. The overwings on an NG (and the bus AFAIK) will open, even with a partially pressurised cabin. Can't remember if the overwing locks will still be engaged in that config, though - jeez, you forget a lot when you don't fly the aircraft for 8 months
I think the best call the skipper made was declining the TEB option, despite ATC trying to be helpful. It looks might tempting from that position, but 24 is a bit short for a 320, and it's a long way around to final 01. I'd like to think that I'd have gone for the river as well
There but for the grace of God...
BTW, if both your engines are out (unless you're doing a engine bleeds off takeoff), the cabin should leak down very quickly. The overwings on an NG (and the bus AFAIK) will open, even with a partially pressurised cabin. Can't remember if the overwing locks will still be engaged in that config, though - jeez, you forget a lot when you don't fly the aircraft for 8 months
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From the pix on the barge, it appeared the A320 pressure vessel was surprisingly compromised in this apparently exemplary touchdown. If so, the Ditch switch could be done away with and the outflow valves ignored.
Was the belly of the 737 that ditched in Indonesia badly damaged, or was its pressure vessel intact?
GB
Was the belly of the 737 that ditched in Indonesia badly damaged, or was its pressure vessel intact?
GB
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I don't know where I'd find stall speed vs flap configuration published for the 747 (or any other transport airplane, for that matter). Therefore, I can only assume that flap maneuvering speed is based on a consistent margin above the stall speed for that configuration.
The "or two?" comment you make, however, is also relevant. The second increment of flaps on a 747 gives a total of 40 KT reduction in maneuvering speed, of the grand total of 80 KT reduction from clean to Flaps 30. So, in the case of the 747 it IS likely accurate to state that 50% of the stall speed reduction is attained in the first TWO "notches" of flap. Likewise, 75% is attained by the third "notch," with 3 "notches" remainin
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Intruder - the data I provided is from our AFM. That data is provided by Boeing. If it's not in your manuals the manuals I"ve seen at our training facilities have a lot more information in them then what is provided to the pilots.
I doubt that the last flap selection has the same stall protection as the first notch on a 747. On the 6 transport aircraft that I've flown the overwhelming stall reduction is provided at the first flap selection, while the last selection has more drag vs. stall protection.
The "or two?" comment you make, however, is also relevant. The second increment of flaps on a 747 gives a total of 40 KT reduction in maneuvering speed, of the grand total of 80 KT reduction from clean to Flaps 30. So, in the case of the 747 it IS likely accurate to state that 50% of the stall speed reduction is attained in the first TWO "notches" of flap. Likewise, 75% is attained by the third "notch," with 3 "notches" remainin
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Intruder - the data I provided is from our AFM. That data is provided by Boeing. If it's not in your manuals the manuals I"ve seen at our training facilities have a lot more information in them then what is provided to the pilots.
I doubt that the last flap selection has the same stall protection as the first notch on a 747. On the 6 transport aircraft that I've flown the overwhelming stall reduction is provided at the first flap selection, while the last selection has more drag vs. stall protection.
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Class consensus was as follows:
APU for hydraulic power for flight controls more desirable than manual reversion
In order to touch down with as much control as possible more important than
having the APU door remain open. A controlled touch down was very key to
the successful outcome.
Alternate flaps switch to fully extend leading edge devices to quickly widen
the stall margin. Standby hydraulic pump will automatically be activated as
a result which will assist rudder control.
Engine bleed switches off.
Outflow valve closed.
Flap and gear inhibit switches would be nice.
Aircraft sink rate could be a real issue with Flaps 40.
Trading altitude for energy at low level in order to plan as controlled a
touch down as possible certainly would be needed with Flap 40 and would
be disasterous if you got it wrong.
A tremendous amount of good luck and skillful flying and good decision making
played a very big role to the outcome as well.
Point of discussion: Systems knowledge and the need to be innovative as per
Boeing preamble to checklist points out, not all situations can be planned for
And several elements of checklist maybe required as well a thorough
knowledge of aircraft systems will be of great aid.
As pointed out, only 3 and a half minutes from thrust loss to touch down and
this event was done as far as preparing for ditching was concerned.
Truly remarkable event and a very lucky outcome.
Safe flying all.
ea306
APU for hydraulic power for flight controls more desirable than manual reversion
In order to touch down with as much control as possible more important than
having the APU door remain open. A controlled touch down was very key to
the successful outcome.
Alternate flaps switch to fully extend leading edge devices to quickly widen
the stall margin. Standby hydraulic pump will automatically be activated as
a result which will assist rudder control.
Engine bleed switches off.
Outflow valve closed.
Flap and gear inhibit switches would be nice.
Aircraft sink rate could be a real issue with Flaps 40.
Trading altitude for energy at low level in order to plan as controlled a
touch down as possible certainly would be needed with Flap 40 and would
be disasterous if you got it wrong.
A tremendous amount of good luck and skillful flying and good decision making
played a very big role to the outcome as well.
Point of discussion: Systems knowledge and the need to be innovative as per
Boeing preamble to checklist points out, not all situations can be planned for
And several elements of checklist maybe required as well a thorough
knowledge of aircraft systems will be of great aid.
As pointed out, only 3 and a half minutes from thrust loss to touch down and
this event was done as far as preparing for ditching was concerned.
Truly remarkable event and a very lucky outcome.
Safe flying all.
ea306
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There is one crucial thing everyone seems to be missing. What if those windmilling engines don't produce enough enough hydraulic pressure to extend flaps? Until the APU comes on you don't have any other way to do it (battery doesn't power ALT flap extention).
Here is a question that I can't find in our FCOM. Can you even extend flaps above flaps 15 with alternate flap extention?
I think QRH Ditching is very poorly written. it clearly assumes that engines are running. In Sully situation following that checklist blindly would make more harm than help. Putting yourself into manual reversion just for the purpose of closing the APU inlet??? That's madness.
We're used to flare with both engines running and putting it to IDLE at 20ft. Doing it with no engines would require relatively high elevator forces. In manual reversion that would be a recipy for disaster. I think flaps 30 would be a better idea.
Here is a question that I can't find in our FCOM. Can you even extend flaps above flaps 15 with alternate flap extention?
I think QRH Ditching is very poorly written. it clearly assumes that engines are running. In Sully situation following that checklist blindly would make more harm than help. Putting yourself into manual reversion just for the purpose of closing the APU inlet??? That's madness.
We're used to flare with both engines running and putting it to IDLE at 20ft. Doing it with no engines would require relatively high elevator forces. In manual reversion that would be a recipy for disaster. I think flaps 30 would be a better idea.
