Fail Passive B777

[Spooky 2]

I know we have been down this road several times but if could ask one more time for your indulgence;

Can anyone think of a scenario where the pilot could execute at CATllla Fail Passive approach and use an AH in lieu of a DH. If so, is this unique to OPS1 criteria.

Why do they make this so damn hard? :confused:

[Wizofoz]

Might be crossing regulatory jurisdictions here, but no- CatIIIa is a DH less than 100', greater or equal to 50', and I'm not aware of any other way it can be done.

[B737NG]

No it remains general that way: CAT IIIa DH, usualy 50ft or higher. Remind you that the HUD Airplanes = B737, B787, EMB´s can do manual CAT IIIa Approaches with 50ft DH.

The chain must be strong enough to hold the weakest part. CAT IIIb has as well some DH´s at the discretion of the regulatory Authorithy. You have a AH and they require you also a DH in some cases. I do not agree with the 25ft that some Desk flyer decide, the moment the AT walks to idle and the G/A takes even longer to accelerate if you opt for the G/A. We discussed that issue with the DGCA but the opposite result was offered: DH 50 ft for CAT IIIb, a clear sign of not understanding what the system is capable for and how it is designed. It was just to show muscle.... but no brain.

Fly safe and land happy

NG

[rudderrudderrat]

Hi B737NG,
I do not agree with the 25ft that some Desk flyer decide,
That's the was the way it was in the 80s. Only the UK CAA permitted us to do NO DH approaches - everywhere else we were required to have a mini DH and be able to see at least one runway centre line light before continuing to Land.

On the GA - we thumped the runway with the gear before climbing away, so we would have squashed whatever was beneath us hiding the centre line light anyway.

[Denti]

And then there is the case of having a fail operational autoflight system with fail passive rollout, which is labeled as CAT IIIb under EU-OPS but requires 50ft DH and 125m RVR. Always some odd exceptions to the rule.

[B737NG]

Yes the good old times, when systems where not as reliable as today and the man was the flying equipment and not the equipment the man......

But with the sources we have today (technical reliability) we could easy run by no DH and AH alone at the CAT IIIb. You still find guy´s who try to convert the decision G/A into a land when the wheel bump .... calls for desaster !!!

Just my humble opinion: Eliminate all sources of error at the root.


Fly safe and land happy

NG