A 320 Landing with abnormal landing gear

[Magnetic Iron]

1) If you were to have a Landing gear abnormal with one Landing gear abnormal.

Airbus says reduce fuel to a safe minimum. Which leaves a fair bit of latitude.

Airbus does not discuss the possibility of a low pass by the tower over the runway so ATC can have a good look at your undercarriage situation. ( Also you could burn excess fuel doing this ). Does anyone know why ?

As you are so sure not having a gear down from not having the Ldg gear memo and or green triangle ?

2) EASA AD No.: 2013-0288
How does compliance with these AD´s work ? How long does a operator have to fix such items ? Could one provide a link regarding AD compliance or it depends on the operators MCM ?

Have many of you out there experienced problems with the MLG door actuators ?


¨Prompted by these findings, EASA issued Emergency AD 2013-0132-E to require identification of the affected aeroplanes to establish the configuration and, for those aeroplanes, repetitive inspections of the opening sequence of the MLG door actuator and, depending on findings, replacement of the MLG door actuator. That AD also provided an optional terminating action by disconnection of the interlink for certain LGCIUs, or in-service modification of the aeroplane through Airbus SB A320-32-1407 (equivalent to production MOD 153655).



Some operators reported slow operation of the main landing gear (MLG) door opening/closing sequence, leading to the generation of ECAM warnings during the landing gear retraction or extension sequence.
Investigations showed that the damping ring and associated retaining ring of the MLG door actuator deteriorate. The resultant debris increases the friction inside the actuator which can be sufficiently high to restrict opening of the MLG door by gravity, during operation of the landing gear alternate (free-fall) extension system.
This condition, if not corrected, could prevent the full extension and/or down locking of the MLG, possibly resulting in MLG collapse during landing or rollout and consequent damage to the aeroplane and injury to occupants.
EASA AD 2006-0112R1 was issued to require repetitive inspections of the opening sequence of the MLG door in order to identify the defective actuators, and to introduce as an optional terminating action Airbus production Modification¨

Thanks in advance.

[Flo121142]

How does compliance with these AD´s work ? How long does a operator have to fix such items ? Could one provide a link regarding AD compliance or it depends on the operators MCM ?
It says in the AD itself...there are different times give for the different steps of the AD, starting at the bottom of the first page: http://ad.easa.europa.eu/blob/easa_ad_2013_0288.pdf/AD_2013-0288_1

[Longhitter]

A few considerations around question 1:

- A low pass over the runway is a non-standard flight maneuver in a non-standard configuration that little to no crews have practiced in real life or in a simulator. Most operators forbid the flying of such a maneuver as one can easily end up in low speed / high AoA / high thrust situations close to the ground (and remember: alpha floor is inhibited below 100 feet RA as was painfully demonstrated in France)

- ATC staff, or actually anybody, is not able, nor qualified, to assess if a gear leg is up/down and locked from the ground. Wrong assessment of gear position leads to false assumptions about gear position and safety (you could land with the expectation that the gear is safe and have a nasty surprise once on the runway).

No down and locked indication on wheel page or gear indicators after applying the appropriate procedure: assume the worst.

[Magnetic Iron]

Thanks for the answers

[FLEXPWR]

Longhitter,

As a side note, the example you give is not entirely correct. In that instance in France, the pilot deliberately de-activated the ATHR (not switched off, but de-activated for the remainder of the flight, without possibility to re-activate). Even above 100'RA, the alpha floor would not have worked anyway.

Back to the subject, a low pass can give an approximate evaluation of the gear position, but no ATC controller will put their a$$ on the line and confirm anything, and certainly not saying it's "down and locked"...

[Longhitter]

Exactly, and an "approximate evaluation of the landing gear position" is absolutely useless and not worth the non-standard maneuvering to get one...

[compressor stall]

Better to brief the gear abnormal and not need to use it than brief for the normal and need the abnormal.

[macdo]

Low pass over the tower is banned in our manual too. I believe the most problematic bit of the a320 gear is the nosewheel steering getting jammed hard over, theres a good video on youtube of a successful landing with that problem.
One green triangle on each leg on the SD page or the Green Ldg Gear Dn Memo are enough to confirm gear down and locked according to our AFM.

[Tech_Log]

At my carrier the MLG door actuator inspections are carried out every 7 days, aligned with the weekly check. It's an operational check inspection carried out on the ramp and requires a licensed engineer to stamp it off as done.
Hope that answers the question regards the AD.


Safe flying
Tech_Log