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5150
5th May 2002, 10:58
Friend and I were watching the Black Box vid last night and were wondering if they stood more of a chance of remaining upright if they had kept the gear up, as oppose to landing at +200kts and 1600fpm?

Any ideas/experiences?

lomapaseo
5th May 2002, 11:25
At 1600 fpm you want the gear down. and as much between your butt and the hard ground as you can get.

Tinstaafl
5th May 2002, 12:39
The energy that gets used to compress the gear then deform it as the structure fails is no longer present to deform the passengers.

Georgeablelovehowindia
5th May 2002, 21:19
The aircraft involved was a DC-10-10. On the -30 you'd have to have the additional presence of mind to isolate the centre gear leg to avoid it punching up into the cabin...

lomapaseo
6th May 2002, 09:59
>The aircraft involved was a DC-10-10. On the -30 you'd have to have the additional presence of mind to isolate the centre gear leg to avoid it punching up into the cabin...<

Gears are attached to large box structures to absorb the loads. I doubt that any punching of these can occur into a cabin.

Wino
6th May 2002, 14:51
In the early days of a 747 a PANAM one dragged the lights a little short of the runway. The center mains were punched up through the cabin and killed a few people. The aircraft was repaired and returned to service.

Cheers
Wino

411A
6th May 2002, 15:54
On takeoff from SFO, actually....wrong flap setting. Should have been 20, but ten selected instead. After that, PanAm adopted a "configuration check" (flaps, spoilers, stab trim, compass heading) as the last item on the before takeoff checklist.
Have to admit that, altho have received training from several other airlines, PanAm training was the very best, IMHO.
No BS, just the facts.

Georgeablelovehowindia
6th May 2002, 20:00
lomapaseo: I used to be DC-10 type-rated. In the event of a left or right main gear failure to extend, isolating the centre gear leg is a consideration, for that very reason.

Shore Guy
6th May 2002, 20:25
411 and all,

Tried to find the NTSB link to the PanAm 747 SFO accident without any luck....As I recall, that aircraft went through the approach light stanchions at the opposite end of the runway.
One or more penetrated the fuselage. I believe this accident paved the way into research on frangible approach light stantions.

Yes, the aircraft was repaired and I believe is still operating (UPS).

InitRef
7th May 2002, 01:05
Shoreguy, you can find a copy (albeit a medium-quality scanned version) at ERAU online:
http://amelia.db.erau.edu/reports/ntsb/aar/AAR72-17.pdf

'%MAC'
7th May 2002, 01:20
Thanks 411A, that's a useful final check. I'll put that into my bag of tricks. Can think of several takeoff incidents/ accidents that might have been avoided had that been used; the Anchorage incident couple months ago, the NWA accident at DTW...

*Lancer*
8th May 2002, 09:53
5150, to remain upright the aircraft would obviously have to not cartwheel. With the gear up or down, the right wing would still have impacted and caused the left to lift up and over...

All things considered they did quite a remarkable job!

Lancer

5150
8th May 2002, 19:10
Absolutely!

Thanks for the interesting replies chaps

5150

Slasher
9th May 2002, 16:41
Yep 411A and I have a mental survivor-checklist when cleared to line up too: flaps set correct, V2 on MCP correct, stab-trim setting correct, T.O. power computation correct. The 4 things that could kill you if they arent right!

boofhead
12th May 2002, 22:24
I've wondered if the Sioux City airplane had managed to land, at over 200 knots and with no hydraulics (thus no brakes, no reverse, no speed brakes etc) how would the pilots have managed to stop it? One would hope that they could have landed on the grass, thus using the drag of the gear as it buried itself in the ground, but on a long, hard surface they would have seen the end of the runway, and the buildings located there, coming up pretty fast!
But they did save over half of the passengers, gotta give 'em credit.

Shore Guy
13th May 2002, 07:42
Slasher, 411, and all:

My "safety check" on the 757/767 is: Spoilers, Flaps, Trim (all three axis), RTO, runway on the EHSI (to confirm proper position, runway, and alignment), and "whiskers" on the EADI (on the 757l767 the Pitch Limit Indicator for Windshear guidance only appears when the flaps are out of the up position - another confirmation flaps are down). Normally also have departure runway localiser tuned also to confirm correct runway.

In the last six years, while jumpseating, I have witnessed two aircraft go into position and hold with the flaps up (and commented accordingly). Yeah, the warnings would have probably worked, but.........

KC-10 Driver
14th May 2002, 05:18
The Sioux City tower cleared UA 232 to land on a specific runway (I forget which runway), to which Captain Al Hanes replied, "You want us to make a certain runway? I just hope we make the airport." The whole crew showed immense skill in getting the aircraft as far as they did.

As far as braking, the aircraft would have had brake accumulator pressure, which would have been good for 3-6 manual applications of brakes. This might not have been enough to fully stop the aircraft. However, it would have at least slowed it immensely.

Personally, I have stopped an overweight KC-10 (DC-10-30) with 3 manual brake applications on accumulator pressure only (I must admit I've only had the displeasure to have to do this in the simulator -- and we all know the sim always flies exactly like the aircraft).

*Lancer*
14th May 2002, 11:49
Sioux City: United 232 heavy, winds currently 360 at 11, three sixty at eleven, you're cleared to land on any runway.

UAL 232: You don't want to be particular and make it a runway, huh?

Sioux City: ...010 at 11, and there's a runway that closed, sir, that
could probably work too, it runs northeast to southwest.

UAL 232: We're pretty much lined up on this one, here, I think we will be.

Sioux City: United 232 heavy, roger sir, that's a closed runway,
that'll work, sir. We're getting the equipment off the runway, and
they'll line up to that one.

UAL 232: How long is it?

Sioux City: At the end of the runway is just a wide open field, sir,
so the length won't be a problem.

UAL 232: OK.

[GPWS alarm on CVR]

The actual recording (time edited) is available from a number of sources on the net... it makes interesting listening!

Lancer

*Lancer*
14th May 2002, 11:58
"The first part of the video was taken by a home video camera, showing us in the air.

But that picture in the air is very deceiving. It looks like we have
everything pretty much in control. We were starting a down phugoid, and starting a right bank, 300' in the air. And we just, that's where our luck ran out. We just ran out of altitude, trying to correct it. We had the time in the air, trying to correct it. But that close to the ground, we didn't have time. In an attempt to stop the phugoid and the turn, Dennis added power, and unfortunately the left engine spooled up faster than the right, the first time in the day we noticed that it happened, and the bank increased. And in four seconds, we went from four degrees of right bank, to twenty degrees of right bank, and hit the ground. However, safety experts say the tumbling of the aircraft probably saved a lot of lives. It took up most of the inertia, most of the shock, and allowed the people to get out of the airplane."

- Captain Al Haynes

This is available at http://www.snowcrest.net/marnells/haynes.htm with a lot of other information...

Lancer