Airbus A320 Nosewheel turned 90 degrees 17 times

[Jimmy Hoffa Rocks]

Here is the link to the interim report in which the Nosewheel turned 90 degrees on a A-320 on landing.

It has happened at least 17 times, With 7 different failure modes, this appears to be the 8th.
Curiously not mentioned in the report they also lost Autothrust, Why ?
Also any comments on the electrical interconnectivity issue ?
Sorry, but we need more info from Airbus on this.


http://www.fomento.gob.es/NR/rdonlyr...N_PROV_ENG.pdf

[27ace]

Not sure if it happened again last week to Egyptair A320. Have a look at the link below and judge for yourself.

Incident: Egyptair A320 at Nairobi on Jun 6th 2012, veered off runway on landing

[Airbus_a321]

Thanks 27,
that was also my thinking as I saw this picture

http://www.pprune.org/african-aviati...r-overrun.html

http://www.pprune.org/african-aviati...r-overrun.html

[EEngr]

I'm not an Airbus or landing gear authority. But I recall reading somewhere that having the nose gear fail over to the 90 degree position for steering system faults is intentional. Better to land with the wheel at 90 degrees and scrub some rubber off than to have it fail at some lesser angle and provide an unwanted (and uncontrollable) steering force.

Either that or Airbus employed an ex-shopping cart wheel designer.

Airbus experts feel free to jump in and comment.

[fantom]

I am fairly certain they have all been attributed to maintenance wrongdoings.

[Airbus_a321]

@EEngr

but if they did it maybe intentionally at 90 degrees, why not make it intentionally to center in straight forward position ?
just my 2 cents

[Beeline]

I read it as two unrelated faults.

The generator cables being one and the nose landing gear suffering a centering cam failure.

I remember having to perform lots of inspections on the NLG lugs 5 or 6 years ago for this problem. Can't remember the incident off the top of my head.

In addition I think a NLG shock absorber fault TSM ref is to perform a lug inspection.

[EEngr]

but if they did it maybe intentionally at 90 degrees, why not make it intentionally to center in straight forward position ?

The way I remember it, it has something to do with the steering control unit doing some sort of centering test prior to landing. There is some interaction between the mechanical failures and the control s/w sensing (or failing to sense) the gear being in a straight ahead position. So it drives the gear to 90 degrees (to a mechanical stop?) rather than leaving it in some unknown configuration.

The mechanical failure results in the gear not centering. The s/w picks this up and forces it hard over. Something like that. It sounded like the mechanical failure alone could leave the gear in some unknown position (that's bad).