747-600X
Topic Author
Posts: 2492
Joined: Wed Jan 05, 2000 3:11 am

Obviouse Problem ... Must Have Solution!?!?!

Sat May 06, 2000 3:45 am

I was just wondering - what do they do with a jet if they can't get the landing gear down? Esp. the majority low-wingers? Even a slow landing would still tear your engines and probably wings to peices! I'm thinking someone has to have some solution for this but I can't imgaine what.
 
Ralgha
Posts: 1589
Joined: Tue Nov 09, 1999 6:20 pm

RE: Obviouse Problem ... Must Have Solution!?!?!

Sat May 06, 2000 9:44 am

If they can't get the gear down using any of the backup/emergency extension systems, they land on the belly.
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
 
Guest

RE: Obviouse Problem ... Must Have Solution!?!?!

Sat May 06, 2000 10:11 am

If the emergency systems fail, the plane will re-route long enough for the runway to be covered with a thick layer of foam (to prevent explosions and fire), and the plane will come in as slowly as it can, then land on its belly.
 
Guest

RE: Potential Damage

Sat May 06, 2000 12:25 pm

Considering the the simplicity of most MLG alternate gear extension (release the uplocks and gravity free fall) the possibility of all the gear being locked up are pretty slim. I am only familiar with a 747-100 that had wing gear that did not lower. I have heard of aircraft landing with the nlg up that had very little damage (seen videos of a 747-400). The pylons are designed not to transfer excessive loads to the wing structure, so it is possible to isolate the damage to the engine and strut. Even the hull damage might not be too excessive, I have never actually seen it done, but I have heard that they foam the runway.
 
747-600X
Topic Author
Posts: 2492
Joined: Wed Jan 05, 2000 3:11 am

About Foamed Runways...

Sat May 06, 2000 12:49 pm

how do they keep the wings from getting torn off when the engines hit the ground???
 
Guest

RE: Obviouse Problem ... Must Have Solution!?!?!

Sat May 06, 2000 1:23 pm

I am speaking best case scenario, but the fuse pins in the pylon should shear without structural damage to the wing.
 
Guest

RE: Obviouse Problem ... Must Have Solution!?!?!

Sat May 06, 2000 1:25 pm

Couldn't they just land in water?  
 
747-600X
Topic Author
Posts: 2492
Joined: Wed Jan 05, 2000 3:11 am

Pedro757

Sun May 07, 2000 1:14 pm

A 747 did this once, actually it didn't land in the water, it slid off a runway into the water. It floated quite nicely, as I recall having heard, but at even the slowest speeds a water landing could be ungodly rough and painful for the passengers, not to mention that at high speeds water is like concrete, and a foamed up runway for a smooth skidded landing could be a lot nicer, even for the aircraft. The engine thing still gets me, I guess I always assumed if they were on tight enough to push an entire jumbo jetliner forward, they wouldn't just pop off that easily, but what do I know, it was my question after all!
 
F-WWAI
Posts: 129
Joined: Thu Dec 30, 1999 7:41 am

RE: Obviouse Problem ... Must Have Solution!?!?!

Tue May 09, 2000 12:21 am

Let's call it "wheels-up landing"
the aircraft are designed for it. Boeing uses fuse bolts so the engines drop off after impact, Airbus uses more rigid design so the engines stay on wing and the aircraft can slide on them to stop (they look different though after such manoeuver).
the pilot runs the fuel tanks as dry as recommendable, does a nice approach and shuts the engines down when the aircraft touches ground.
recent experience have shown that this usually works quite well, however I would prfer beçing on another flight that day.
 
MD-90
Posts: 7835
Joined: Mon Jan 17, 2000 12:45 pm

RE: Landing Gear-less Airliners

Tue May 09, 2000 5:51 am

I know of one Eastern 727 that landing in Miami (I think) with no gear. The runway was foamed and the 727 suffered only minimal damage. They had to replace a few belly skins, but that was it.

I wonder whatever happened to that Air Canada 767-200 that ran out of fuel. I remember seeing a picture of it with the nosegear collapsed. The engines didn't touch the ground. I wonder if the 737 Classics or NGs would. The Classics have flatter nacelles, the NGs taller landing gear. I'd want to be in a MD-80/90, 717, or 727 with a foamed runway if I was going to be in a no gear accident. Plus it's a shorter distance to the ground if the emergency slide at your door doesn't deploy.

Who is online