Sponsor Message:
Aviation Technical / Operations Forum
My Starred Topics | Profile | New Topic | Forum Index | Help | Search 
Can One Land With Extended Gear Doors?  
User currently offlineA380900 From France, joined Dec 2003, 1118 posts, RR: 1
Posted (5 years 10 months 1 week 2 days 5 hours ago) and read 5179 times:

Is it a design requirement that you could land a plane with the gear doors extended without damage to them? Or do engineers disregard this? Does it depend on the plane?

18 replies: All unread, jump to last
 
User currently offlineEMBQA From United States of America, joined Oct 2003, 9364 posts, RR: 11
Reply 1, posted (5 years 10 months 1 week 2 days 4 hours ago) and read 5160 times:

Yes... you can. Aircraft that have body doors are designed to clear the ground. If you look in the data base there are several pictures of just that case. 757 is a biggie.....


"It's not the size of the dog in the fight, but the size of the fight in the dog"
User currently offlineTristarSteve From Sweden, joined Nov 2005, 4069 posts, RR: 33
Reply 2, posted (5 years 10 months 1 week 2 days 4 hours ago) and read 5136 times:

When the undercarriage is extended in emergency by using the freefall handles/switches, the gear doors will open and not close again.
In many cases the main gear doors will touch the runway when the aircraft lands, but there are rub strips built into the doors for this.
On the B747, if you open the body gear doors on the ground, it is very possible that they will hit the wheels if the aircraft is heavy. Good catch this. You open them on arrival, refuel the aircraft, then can't close them again!


User currently offlineBroke From United States of America, joined Apr 2002, 1322 posts, RR: 3
Reply 3, posted (5 years 10 months 1 week 2 days 3 hours ago) and read 5117 times:

The main gear doors on the DC-9's will drag if the airplane lands with them open. The reason for landing with the doors open would be a manual gear extention with no hydraulics. Douglas designed a system of cranks, cables, and pulleys to manually closed the doors; the system was unwieldy and unreliable.
The final fix was to install a skid on each main landing gear door. If you landed with the doors open, just change the skids.


User currently offlineDH106 From United Kingdom, joined Jun 2005, 626 posts, RR: 1
Reply 4, posted (5 years 10 months 1 week 2 days 2 hours ago) and read 5096 times:

The new A380 has all sorts of little fillets on it's gears doors designed to allow them to be opened in various scenarios. General retraction/extention with oleos extended & bogies tilted requires a little fillet on the inner body gear doors to fold to clear the rear wheels of the tilted 6 wheel bogie. There's a similar fillet further forward on the same door that I speculate is for when the doors need to be opened on the ground with bogie flat & oleos compressed - to clear the center axle wheels of the body gear bogie. Also, the inner wing gear doors have a fillet at their rear edge that doesn't open with the rest of the door but folds up into the fuselage. This is so the door edge clears the body gear front wheels which protrude slightly into the wing gear well area.


...I watched c-beams glitter in the dark near the Tanhauser Gate....
User currently offlinePGNCS From United States of America, joined Apr 2007, 2858 posts, RR: 48
Reply 5, posted (5 years 10 months 1 week 1 day 23 hours ago) and read 5048 times:



Quoting A380900 (Thread starter):
Is it a design requirement that you could land a plane with the gear doors extended without damage to them?

It's not a requirement, though in most cases the doors won't contact the ground.

Quoting EMBQA (Reply 1):
Yes... you can. Aircraft that have body doors are designed to clear the ground.

Not all do. DC-9/MD-80/MD-90 gear doors sit on the ground after manual extension (loss of right hydraulic system being the common scenario). They are designed to be aerodynamic to an extent and as the aircraft slows they gradually lower to the ground onto big blocks of metal which are all that gets scraped (if it all works correctly, and it usually does). Of course maintenance will come and pin the gear and stow the doors before the aircraft moves off the runway.

Of course the 737 gets around the issue altogether by not having main gear doors.

Quoting Broke (Reply 3):
The main gear doors on the DC-9's will drag if the airplane lands with them open. The reason for landing with the doors open would be a manual gear extention with no hydraulics.

 checkmark  Or without the right system, anyway.


User currently offlineBoeing767mech From United States of America, joined Dec 2000, 1031 posts, RR: 3
Reply 6, posted (5 years 10 months 1 week 1 day 18 hours ago) and read 4940 times:



Quoting A380900 (Thread starter):
Is it a design requirement that you could land a plane with the gear doors extended without damage to them?

The flight test airplanes of the Convair 880's had the MLG gear doors openned until the gear was retracted, during flight test the sequence valve for the doors was changed.

http://www.youtube.com/watch?v=BsRcRxXv1V8

you can see it in this video.

David



Never under-estimate the predictably of stupidty
User currently offlineAvt007 From Canada, joined Jul 2000, 2132 posts, RR: 5
Reply 7, posted (5 years 10 months 1 week 1 day 14 hours ago) and read 4857 times:

The F28 doors hit the ground, so there was a crank and pulley system for the crew to use to raise them enough not to drag. Some had the pulley in the galley floor, but that might upset the pax. Others had the pulley in the flight deck.

User currently offlineDeltaGuy From , joined Dec 1969, posts, RR:
Reply 8, posted (5 years 10 months 1 week 1 day 13 hours ago) and read 4847 times:

You can land a Gulfstream doors-down as well.

Now how about a 737? Wait...not a problem.

DeltaGuy


User currently offlineDH106 From United Kingdom, joined Jun 2005, 626 posts, RR: 1
Reply 9, posted (5 years 10 months 1 week 1 day 10 hours ago) and read 4801 times:

The British 1-11 had the same problem as the DC-9/MD-80/90 - open doors will drag as the aircraft sits low on the ground.


...I watched c-beams glitter in the dark near the Tanhauser Gate....
User currently offlineHAWK21M From India, joined Jan 2001, 31712 posts, RR: 56
Reply 10, posted (5 years 10 months 1 week 1 day 9 hours ago) and read 4777 times:

Sure can on a B757.If the Alt gear extension is utilised,there is no means of retracting the doors.
regds
MEL



Think of the brighter side!
User currently offlineAvt007 From Canada, joined Jul 2000, 2132 posts, RR: 5
Reply 11, posted (5 years 10 months 1 week 17 hours ago) and read 4617 times:

For that matter, an F28 can land with the cabin door open with only minor scrapes.

User currently offlineKELPkid From United States of America, joined Nov 2005, 6428 posts, RR: 3
Reply 12, posted (5 years 10 months 1 week 11 hours ago) and read 4563 times:



Quoting A380900 (Thread starter):
Is it a design requirement that you could land a plane with the gear doors extended without damage to them?

Certainly not the case with the Cessna 210...I was on board one once when a hydraulic gear sequencer acted up, and the doors remained open. Shower O' Sparks time  Wow! The aircraft had to have the gear doors to be replaced after that incident.



Celebrating the birth of KELPkidJR on August 5, 2009 :-)
User currently offlineDH106 From United Kingdom, joined Jun 2005, 626 posts, RR: 1
Reply 13, posted (5 years 10 months 1 week 10 hours ago) and read 4560 times:

Quoting KELPkid (Reply 12):
Certainly not the case with the Cessna 210...I was on board one once when a hydraulic gear sequencer acted up, and the doors remained open. Shower O' Sparks time The aircraft had to have the gear doors to be replaced after that incident.

Really? Didn't think the 210 had doors on the mains - don't they just pivot back into holes in the rear fuz?



No, you're right on checking photos - some do have doors.  Smile

[Edited 2009-02-17 22:52:44]


...I watched c-beams glitter in the dark near the Tanhauser Gate....
User currently offlineKELPkid From United States of America, joined Nov 2005, 6428 posts, RR: 3
Reply 14, posted (5 years 10 months 1 week 10 hours ago) and read 4553 times:



Quoting DH106 (Reply 13):
Really? Didn't think the 210 had doors on the mains - don't they just pivot back into holes in the rear fuz?

Depends on the model. The last 210's built didn't have gear doors (on the mains), and a popular STC mod is to remove the gear doors and replace them with the flush fitting skin from later 210's. The 1962 210B definitely has gear doors on the mains, and another door for the gear legs. It is very similar to an airliner, in that the main gear doors are only supposed to be open during the extension and retraction sequences. If you know what you are doing, you can even open them on the ground for a pre-flight inspection (I don't remember how to do this without making her end up on the belly).



Celebrating the birth of KELPkidJR on August 5, 2009 :-)
User currently offlineHAWK21M From India, joined Jan 2001, 31712 posts, RR: 56
Reply 15, posted (5 years 10 months 1 week 10 hours ago) and read 4553 times:



Quoting DH106 (Reply 13):
some do have doors.

Why the option?
regds
MEL...



Think of the brighter side!
User currently offlineKELPkid From United States of America, joined Nov 2005, 6428 posts, RR: 3
Reply 16, posted (5 years 10 months 6 days 22 hours ago) and read 4491 times:



Quoting HAWK21M (Reply 15):
Why the option?
regds
MEL...

Hi MEL, it wasn't really an option, Cesnna deleted main gear doors (and the gear leg doors, too) on most late-production (1979-1986) single retracts. The door mechanism system is inordinately complex (a hydraulic plumbing and micro-switch nightmare), and prone to failure. Mechanics who know the Cessna retract system well are sought after by the owners of such birds for this reason...  Wink

However, a few people have STC'ed refitting earlier Cessna retract single gear doors with the "wheel slots" from later models, which significantly improves the system from a maintenance point of view.



Celebrating the birth of KELPkidJR on August 5, 2009 :-)
User currently offlinePC12Fan From United States of America, joined Jan 2007, 2466 posts, RR: 5
Reply 17, posted (5 years 9 months 2 weeks 2 days 17 hours ago) and read 3999 times:

I've actually seen a couple emergency landing on the DC-9/MD-80 series when the main doors are down. Makes a neat show but they are designed to handle those scenarios.


Just when I think you've said the stupidest thing ever, you keep talkin'!
User currently offlineHAWK21M From India, joined Jan 2001, 31712 posts, RR: 56
Reply 18, posted (5 years 9 months 2 weeks 1 day 8 hours ago) and read 3743 times:



Quoting KELPkid (Reply 16):
However, a few people have STC'ed refitting earlier Cessna retract single gear doors with the "wheel slots" from later models, which significantly improves the system from a maintenance point of view.

Interesting.
Also a def weight saving here too.How much approx?
regds
MEL.



Think of the brighter side!
Top Of Page
Forum Index

Reply To This Topic Can One Land With Extended Gear Doors?
Username:
No username? Sign up now!
Password: 


Forgot Password? Be reminded.
Remember me on this computer (uses cookies)
  • Tech/Ops related posts only!
  • Not Tech/Ops related? Use the other forums
  • No adverts of any kind. This includes web pages.
  • No hostile language or criticizing of others.
  • Do not post copyright protected material.
  • Use relevant and describing topics.
  • Check if your post already been discussed.
  • Check your spelling!
  • DETAILED RULES
Add Images Add SmiliesPosting Help

Please check your spelling (press "Check Spelling" above)


Similar topics:More similar topics...
Landing With Gear Doors Open- Emergency Landing? posted Tue Jun 24 2008 17:30:31 by JoePatroni
CRJ Nose Gear Doors posted Tue Dec 11 2007 08:14:15 by Pilotboi
DC-8 Landing Gear Doors Open On Ground. Why? posted Tue Apr 17 2007 01:50:02 by Jeffry747
KingAir 350 With Extended Nose? posted Fri Dec 8 2006 02:38:30 by ATCT
Runway 1000ft Shorter Than Usual, Can You Land? posted Sun May 21 2006 11:55:44 by JulianUK
A380 Gear Doors - Missing Fillet posted Tue Dec 13 2005 15:11:25 by DH106
No Power To Landing Gear Doors? posted Thu Jul 14 2005 22:33:52 by DColeMAN
A380 Main Gear Doors posted Thu Jun 23 2005 09:27:08 by DH106
Boeing / Douglas Gear Doors Don't Close? posted Thu Apr 21 2005 00:36:31 by AA737-823
Can A LearJet Land And Takeoff On A 2500 Foot Runway posted Wed Feb 16 2005 05:37:35 by AirWillie6475

Sponsor Message:
Printer friendly format