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airsp
3rd Dec 2011, 11:02
Hello,

I'm not working with the Airbus SOP.

- What's written about the use of REV and ABRK for landing ?
Example : is it permitted to use IDLE REV + LOW ABRK on wet runways ?

- Engine Anti-ice
With +9°C, no precipitation, but the taxiway is damp.
Are the engine anti-ice mandatory ?

Thank you

Nick 1
3rd Dec 2011, 12:36
FCOM:
ICING CONDITIONS Applicable to: ALL

Icing conditions may be expected when the OAT (on ground and for takeoff), or when the TAT (in flight) is at or below 10 °C, and there is visible moisture in the air (such as clouds, fog with low visibility of one mile or less, rain, snow, sleet, ice crystals) or standing water, slush, ice or snow is present on the taxiways or runways. WARNING Pilots must turn on the engine anti-ice system, when temperature and visible moisture meet these criteria, and should not wait until they see ice building up.

FOLLOWING LANDING PROCEDURES.................................................. ..........................CONSIDER ‐ Avoid landing on contaminated runways if the antiskid is not functioning. The use of autobrake LOW or MED is recommended provided that the contamination is evenly distributed. ‐ Approach at the normal speed. ‐ Make a positive touchdown after a brief flare. ‐ As soon as the aircraft has touched down, lower the nose wheel onto the runway and select maximum reverse thrust. Do not hold the nose wheel off the ground. ‐ If necessary, the maximum reverse thrust can be used until the aircraft is fully stopped.
This is for Cont. RWY .

Use your judgment , why on, maybe, short and wet runway you want to use just a little of your braking capability? Start with MAX-REV and AB-MED , then see the progress and , if needed adjust it manually.

Bus Driver Man
3rd Dec 2011, 14:34
Example : is it permitted to use IDLE REV + LOW ABRK on wet runways ?

The autobrake will give a constant deceleration.
For LOW: 1,7m/s2 (5.6ft/s2)
For MED: 3m/s2 (9.8ft/s2)

So if you select LOW for a dry or a wet runway, your stopping distance will be the same since your rate of deceleration is the same.

(However, on slippery runways, due to anti-skid operation, it is possible that you do not have this deceleration rate.)

Example:
Autoland distance with autobrake (For 60t, conf FULL):
Dry/LOW = 2130m
Wet/LOW = 2130m
No change for with or without reversers.

However,
Dry/MED = 1520m
Wet/MED = 1570m
No change for with or without reversers.

I assume this is due to anti-skid operation? Somebody correct me if I'm wrong.

airsp
3rd Dec 2011, 15:48
OK, thank you

And what about the reversers on wet runway ?
any sepcification ?

C212-100
3rd Dec 2011, 16:06
Those figures are not the ALD for those specific situations. The figures are merely the value to account for for landing planning. On the safe side... Hence the REV not being considered.