OUCH!!
Hope that you will not do this on your R/C Jets!!!

Should have used Robarts

Looks like it was a Emergency Stop ! (my guess caused the nose gear failure), Take a look at the storage tanks just ahead
Semper Fi
Joe
BTW where did this happen?

guess they ran out of gear pins :-)

Hi,

I don't think it's possible to tell how close the fuel tanks are from the picture. They could be close, or they could be far away. Besides, why would the NLG collapse in an Emergency Stop?? AFAIK, there is no braking on the NLG, so it wouldn't collapse unless it hit something.

There appears to be another plane parked close by, so my guess it that the accident happened in a parking/staging area while the aircraft was parked. It wouldn't be the first time that a ground crewman inadvertantly retracted the LG while attempting to release the parking brake.

John

BA reported an undercarriage collapse on a jumbo at Heathrow
support pins sheared as technicians were working on front leg

OOPS

Weasel33 , you beat me to the punch ! Here's the news article I saw about it :


Jumbo jet collapses at Heathrow

A 320-ton jumbo jet collapsed at Heathrow on Sunday while engineers were carrying out maintenance work.
No-one was injured when the nose of the Boeing 747 crashed to the ground as landing gear folded.

British Airways is investigating why safety pins, which should have secured the landing gear, apparently failed.

The plane, belonging to EVA Air of Taiwan, had been due to leave the west London airport on Saturday, but was delayed by hydraulics problems.

Passengers were sent to a nearby hotel while BA engineers checked the hydraulics systems.

Sorry about that 747drvr
but yours was the better explanation

some poor apprentice will probably be nailed to the hangar wall by his overalls
for a few weeks

Brian

Yes, it is the accident in London HRW on 22/05/04.
This B747-400 belongs to EVA in Taiwan.
According to news in Taiwan, when BA tech. performed troubleshooting for nose gear cyliner hydralic leakage, the nose gear retracted.

The gear pin could be removed without proper communication between operators.

The damage could be costly:

Frames and Skin or even side cargo door
The engine sleeves and nose cones
The body and wing gear cylinders and even struts
All wheels had been overloaded- inspection needed
Antennas
and much more

Why do I know above items? Because, I experience the same situation in my company. The nose gear of our 744 retracted in half trevel only, but we spend over one week to inspect and repair it!!! I hate that!!!

BA tech will lose much money if they are charged by the fault.
Robarts could not handle this accident as well.
The cost could afford all of us to buy the Jetcat P-200, BVMs, SUVs and much more!!! Ouch!!!!

[quote]ORIGINAL: ezflyr


Hi John,

It's not very likely that could happen. Squat switches on the landing gear energize a lockout mechanism on the landing gear lever that prevents it from being raised on the ground. Also the controls are quite different and far apart on this aircraft.

Marc

YES!!
The parking brake level release is just the job for your feet on B744!!
The landing gear retracting need your hand to override the lock and put the level up!!!

No one will confuse about hand and feet.

Gear pin could not be right position!!! I could not belive that gear pin collapsed at that time!!!

Marc,

Do the squat switches physically prevent the lever from being actuated, or do they prevent the gear from retracting even though the lever may be moved to the "retracted" position? I've heard tales of guys in other A/C hitting the gear lever on the take-off roll so the gear comes up the moment the weight comes off the wheels. It doesn't sound safe, but the stories persist...

BTW, I'm still good for a sortie on Friday if the weather holds...

i did that to my Roo!
pull pull streering cables a bit to tight and retract did not lock into place.
required much power to taxi back

Hi Kevin,

The squat switch prevents the gear lever from being actuated. After liftoff the pilot not flying calls "positive rate" when the aircraft is climbing. That's the cue for the PF to call "gear up". I know we've lifted off when I hear the click of the solenoid allowing the gear lever to be raised.

I'm gonna play hooky and fly little jets if you guys are into it. Weather might actually be OK !

Marc

747,

Thanks for the firsthand info on the 747 gear and brake handle placements! On GA aircraft the squat switches are notoriously unreliable, and I know of at least 2 langing gear collapses in Bonanza's where the PIC moved the gear handle to UP instead of retracting the flaps after landing! Oops!!

Happy Flying!

John

Marc-

Vision problems again???

Friday is looking up weather wise. I got the DIY Dean's installed in the F-16 and fixed the plumbing in the Facet, so I'm set.

Thanks for the clarificaiton on the lock-out.

You bet ! Can't see myself going to work !

Marc

During maintenance sometimes you will disconnect the weight on wheels switches and fool them into thinking the aircraft is airborne. Then you can do a "dummy retraction" with the gear pins in place and make sure all the hydraulics are working properly. The key is leaving the gear pins in! have seen this done many times, and only seen one dropped airplane. Most of the older generation of aircraft will allow you to raise the gear handle with the aircraft on the ground, the system is just locked out by the squat switches. Hope that is clear? Thought I would put my 2 cents in.

Man, that would be a drag to have to make that call of shame to the Boss.

How do you start that conversation? ? "Ummm had a little problem working on the jet today......