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teto
9th Apr 2011, 18:49
Hello

a quick question, after wtb locks flaps or slats, what category do you need as a minimum to land?
Looks like CAT 1 ONLY relates only to Flaps/Slats FAULT on the FCOM

thanks

Rubber Dog
9th Apr 2011, 23:25
From the QRH, with slats/flaps jammed, the procedure mentions Auto Pilot use only to 500ft. This is because the system isn't tuned for abnormal configurations. With no AP for landing then you are limited to Cat 1 according to the equipment required for autolands table.

michelda
10th Apr 2011, 04:35
Hi guys,

if flaps are stucked at 3 or more, you are allowed to fly cat II/III approach and landing otherwise only cat I.

Michelda

Torque2
10th Apr 2011, 08:49
Michelda can you provide a reference to back up that statement? If not then I think Rubber Dog has it right.

hetfield
10th Apr 2011, 09:02
Autoland with CONFIG3 on A320?

Torque2
10th Apr 2011, 11:45
A320 FCOM 3.01.22

AUTOMATIC LANDING
CAT II and CAT III autoland are approved in CONF 3 and CONF FULL.

michelda
10th Apr 2011, 17:52
Hi guys,

FCOM 4.05.70 p16 plus FCTM plus instructor manual...etc
nice evening

Michelda

crwjerk
10th Apr 2011, 18:16
Who touches the Aircraft clock anyway??????

9.G
10th Apr 2011, 18:17
michelda, maybe in Italy but not in the rest of Europe that's for sure...

PENKO
10th Apr 2011, 18:25
Is flap stuck in config 3 an abnormal landing config?

Max Angle
10th Apr 2011, 19:40
As long as you have at least Config 3 (rather than just flaps 3, there is a difference) you are perfectly OK to do an autoland. How about stuck between 3 and FULL?, its not a normal landing config so not really allowed but could be very close to 3 or FULL depending when they stopped.

9.G
10th Apr 2011, 20:31
well, now we know FLAP 3 isn't the same a config 3. What if we have config 3 and both channels failed at exactly this position. Still an auto land? :confused:

michelda
10th Apr 2011, 20:56
Ok 9G. I'll land with flaps stuck between 3 and full (according to italian from) and if you want you can go around and proceed to alternate with flap stuck. Have fun.... I hope you have plenty of fuel.....

Michelda

Rubber Dog
10th Apr 2011, 21:51
Cat II and Cat III autolands are approved in Conf 3 and Conf Full. Both being normal landing flap positions. However the original question asked about a wtb problem with no specific info regarding flap or slat positions.

Bus Driver Man
10th Apr 2011, 22:43
well, now we know FLAP 3 isn't the same a config 3. What if we have config 3 and both channels failed at exactly this position. Still an auto land? :confused:

If both flaps channels or both slats channels fail, you lose AP 1 & AP 2.



In my opinion, having your flaps locked at exactly Config 3 or Full seems quite remote.
If it would happen, refering to 3.02.27 p1 (talks about less than config 3) and 4.05.70 p16 (talks about abnormal config), you can autoland if really needed, if your flaps are not at an abnormal config (So only at exactly Config 3 or Full)
Personally, I would only do it if there is absolutely no other option.

zonnair
11th Apr 2011, 06:22
What is the chance, that your flap and slats are jammed by the WTB in the perfect landing config :}

9.G
11th Apr 2011, 08:35
How bout we all read relevant checklist FCOM 3.2.27 in abnormals? :ok:

Max Angle
11th Apr 2011, 18:20
It is a remote possibility I agree but we had a sim. scenario a while back which basically caused a go-around during a CAT3 (runway blocked I think) and the flaps stick at 3 with the WTB brakes on, slats retract as normal. Not a huge amount of fuel left so divert will leave you pretty short with all that drag. Moving the lever back to 3 runs the slats back out and you get a nice "green" conf 3 displayed. As Michelda says, an autoland is a much better (or least worst) option than diverting with the flaps out even if you can get there.

Anything less than conf 3 and you are certainly in uncharted waters which is not a good place to be.

As Bus Driver says some flap faults are going to put you into direct law when the gear goes down so then you are snookered and it really isn't your day. An excellent reason to gas it up when the weather is s**te. :ok:

Bolty McBolt
12th Apr 2011, 01:29
Airbus and the WTB

If the Wing Tip Brakes WTB are engaged in flight it means that the SFCC 1/2 has detected a difference in flap or slat torque drive shaft asymmetry i.e. that the amount of turns input into the flap or slat drive shaft by the Flap/Slat PDU at the inboard end of the shaft has not been replicated at the wingtip. (Asymmetry, Runaway or shaft over speed) Therefore if the WTB are engaged it is probably due to a detected shaft shear in the flap or slat drive system
The WTB will hold the outboard end of the drive shaft to prevent the remaining slats or flaps being driven by air loads to prevent asymmetrical lift.

With this in mind,
The question I ask. Does the book say do an autoland with a WTB message and do you want with this kind of defect?

n.b. Please do not say WTB can come on during flight by changing the clock.

As Max Angle says if the weather is Sh**e you have no choice

9.G
12th Apr 2011, 06:39
FLAPS fault during approach, excerpt from the FCTM:

FAILURE DURING THE APPROACH

The detection of a slat or flap failure occurs with the selection of flap lever during the approach. With A/THR operative, the managed speed target will become the next manoeuvring characteristic speed e.g. S speed when selecting flap lever to 1. At this stage, if a slat or flap failure occurs, the crew will:
. Pull the speed knob for selected speed to avoid further deceleration
. Delay the approach to complete the ECAM procedure
. Refer to LANDING WITH FLAPS OR SLATS JAMMED paper check list.
. Update the approach briefing
In the QRH, the line, "SPEED SEL............VFE NEXT - 5kt" is designed to allow the crew to configure the aircraft for landing whilst controlling the speed in a safe manner. This procedure may involve reducing speed below the manoeuvring speed for the current configuration which is acceptable provided the speed is kept above VLS. The speed reduction and configuration changes should preferably be carried out wings level. The landing distance factors and approach speed increments are available in the QRH. (See FCTM 03.010) Assuming VLS is displayed on the PFD, VAPP should be close to VLS+wind correction, since this speed is computed on the actual slat/flap position.
The AP may be used down to 500 ft AGL. As the AP is not tuned for the abnormal configurations, its behaviour can be less than optimum and must be monitored.
During the approach briefing, emphasis should be made of: . Tail strike awareness . The go-around configuration . Any deviation from standard call out
. The speeds to be flown, following a missed approach
. At the acceleration altitude, selected speed must be used to control the acceleration to the required speed for the configuration. Consider the fuel available and the increased consumption associated with a diversion when flying with flaps and/or slats jammed. Additionally, when diverting with flaps/slats extended, cruise altitude is limited to 20,000 ft.:ok: Auto land really?

I-2021
13th Apr 2011, 09:09
Hi,

the original question was about which landing capability you get with a slat/flap locked, which is CAT 1 as you can understand by reading the landing with slats/flaps jammed paper checklist. Now it is obvious that as a commander you will choose the safest course of actions, in the event that you get a slat/flap locked and you don't have enough fuel to reach an alternate airport with CAT I minimums. What happens from now on, it's PIC judgement. The top one priority is always to be safe. But for the original question, A/P down to 500 ft AGL. Can't see many other ways of reading it.

Cheers.

zonnair
15th Apr 2011, 10:04
What about the hypothetical situation of Max Angle, that actually happened in his sim?

It is a remote possibility I agree but we had a sim. scenario a while back which basically caused a go-around during a CAT3 (runway blocked I think) and the flaps stick at 3 with the WTB brakes on, slats retract as normal. Not a huge amount of fuel left so divert will leave you pretty short with all that drag. Moving the lever back to 3 runs the slats back out and you get a nice "green" conf 3 displayed.

If the capability is still there......

Microburst2002
15th Apr 2011, 19:32
The procedure clearly states that autopilot must be disconnected above 500 ft.

If the WTB actuate just after selecting flaps full so that you remain in CONF 3, then I would consider it as normal config.

But if there is an intermediate position, the autopilot is not certified for autoland.

I-2021
16th Apr 2011, 11:52
The sim scenario of Max Angle is a kind of scenario where you have to evaluate the actual situation rather than just applying the checklist without thinking of what could happen. If you do not have enough fuel to divert in that configuration, the safest option would be performing a Conf 3 autoland as they did. It is a way of checking sound judgement.