Jump to content

Recommended Posts

Posted
A SINGAPORE Airlines plane has collapsed as an engineer conducted routine landing checks before a scheduled flight from Singapore to Hong Kong.No passengers or crew were on board at the time of the incident.

 

The airline said in a statement the nose gear of an Airbus A330-300 “retracted while the aircraft was undergoing a landing gear system check.”

 

“There were no passengers or crew on board at the time. One engineer who was on the aircraft was not injured. Singapore Airlines will be co-operating fully with the authorities in their investigations,” the statement said.

 

It said the damage to the plane would be assessed after it is removed from the gate.

 

The plane had been due to serve flight SQ890, scheduled to depart for Hong Kong from Singapore’s Changi Airport at 7.35am local time. It had arrived from Shanghai’s Pudong International Airport early on Sunday.

 

Another plane was used for the flight to Hong Kong, taking off more than 40 minutes after the scheduled departure time.

 

The collapsed plane had been in service for more than six years, according to records. Its maiden flight was in April 2009.

http://www.news.com.au/travel/travel-updates/singapore-airlines-plane-collapses-at-changi-airport-during-landing-checks/story-fnizu68q-1227565245640

 

 

Posted

I find it strange that only the nose gear collapsed. Any 'tom foolery' would have surely set the whole gear retract in operation although, whether the mains could actually move whilst the plane is stationary, I don't know.

 

 

Posted

It did happen to the earlier Jabiru's if you loaded the nosewheel up on landing. Been strengthened since. Nev

 

 

  • Informative 1
Posted

I remember doing retract tests during maintenance, but to be able to do this we had to disable the safety line that was often an air switch that prevented the retracts from being activated while it was on the ground.

 

 

Posted

There's usually a catch just below the wheel knob on the lever that you have to pull back to lift the gear lever. I imagine it is not operative if the wheels have weight on them using microswitches on the leg. I've never tried for obvious reasons. You need hydraulic pressure for anything to happen, in the retract phase. There's an overcentre function on the extension mechanism usually spring loaded for backup, when it's down. Nev

 

 

  • Agree 1
Posted

No physical catch or lever lock on the A330.

 

However the system air-ground logic won't let you retract on the ground.......unless you've overridden it for maintenance tests!

 

In which case you should have the gear pins in.......which I believe they did not!

 

It is possible/probable that the mains did not retract due to the weight on them and the way in which they need to move, plus the park brake was likely on too. The nose gear simply has to roll forward to retract, and it's not braked.

 

 

  • Agree 1
Guest Andys@coffs
Posted

Most large aircraft I've worked on had a weight on wheels sensor/switch(s)....if it was on the ground and the wings weren't lifting meaning the oleo's were compressed then the retract function was locked out....

 

For the F111's weight on wheels had a whole bunch of other functions as well related to airframe and avionics.......for example in the terrain following radar the radar heads aligned to ground track (logical) in flight but when weight on wheels was present they simply looked directly forward.... ground track with a stationary aircraft and an older inertial nav system could produce some interesting heading to ground track offsets when not flying and the inertial was drifting as they did..... I think if I recall correctly that spoiler deployment as part of the aerodynamic braking on landing was also triggered by weight on wheels....

 

 

Posted

The A330 has numerous inputs to the LGCIU (landing gear control interface unit) and weight on wheels is one of them to determine "air" or "ground" status.

 

This can normally (I'm fairly sure) be overridden through the maintenance computer to test certain systems. I saw this done on a B767 once to test the GPWS system, as the aircraft needs to think it's in the air before certain things will operate.

 

And just to clarify what I wrote previously, this is an interlock on the gear lever to prevent moving it up on the ground, but there's not a physical override catch like on some aircraft.

 

 

Posted

So back to back to my reference to Mr Honey - how was he able to drop the airplane onto the deck ? Or did they not have such interlocks in the 1950s? Refer No Highway in the Sky by Neville Shute.

 

 

Posted

Aviation wouldn't be where it is today (Nor Hollywood) , if it wasn't for Mr Honey and his tenacity to expose the faults

 

of the dreaded Reindeer aircraft.

 

Only old members will understand these posts (Really old)

 

 

Posted

Did my retract endo a couple of weeks ago, was told several times not to rely on the squat switch, and double check gear lever position before master on (and after looking at the mechanism that sounded like good advice, plenty of potential for it to get fauled).

 

At least on a A330 you're not gonna damage the prop 059_whistling.gif.a3aa33bf4e30705b1ad8038eaab5a8f6.gif

 

 

  • Like 2

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...