FNG1

My post refers to a "chated" DH not the procedure for fail passive. Its is my understanding that in a cat III (app. Plate) there is not suppose to be any vertical mins. Well, there are in Amsterdam

Adlerdriver

I'm not sure why you're seeing that on EHAM approaches. All the Fedex CAT-3b approaches into EHAM have a 100' alert height and no requirement to see to land. Perhaps it's a company requirement per OPSPECS?

There are CAT-3 approaches out there with a DH and require see to land. It can be a country rule, airport specific or even a company requirement.

Paris (LFPG) has a 50' DH because the country rules and regs of France require all CAT-3 A&B approaches to have a DH.

Hong Kong has a DH on the ILS 25R CAT-3A approach (at least on our approach plates). I don't know what everyone else shows for mins there. It's not a country rule from what I can see.

FNG1

Thanks for the imput. How do you guys setup the plane then?....what do you put in the radar altimeter? And how does this change fail passive and so on??....for us is not company rule.

Adlerdriver

For a normal CAT-3b approach in the MD-11, we have RVR mins of 300/300/300 with no requirement to see-to-land. We set an alert height (AH) of 100 feet in the radar altimeter. It is flown as a monitored approach with the F/O flying until just prior to AH. The Captain then takes control while the F/O calls "alert height" at 100' as well as monitors aircraft performance with respect to the ILS alignment, etc. Unless the F/O sees a problem, the Captain allows the aircraft to autoland.

With a DH of 50', the procedures and call-outs are the same except when the CAWS system announces "50", the Captain must have sufficient visual references to allow the autoland to continue.

One correction to my earlier post: We recently received a waiver from the French government to conduct CAT-3b approaches without a DH. That raised our RVR mins from 75 meters to 100 meters, but now we are no longer required to use a DH. This waiver is only for Fedex.

I'm not sure I understand your question about fail passive. Under normal conditions, with all equipment operational, the MD-11 is fail operational, not fail passive. I don't believe it is legal to fly a CAT-3b approach with no see-to-land requirement in a fail-passive aircraft.
Maybe you could clarify what you mean by "how does this change fail passive".

DirectTo

I'm not a FedEx'er, and I haven't stayed at a Holiday Inn Express in a few nights...but that seems awfully iffy to be swapping who's flying at 100 feet?

I guess being on autopilot it doesn't change a thing for you guys except who's inside?

Adlerdriver

Correct. The autopilot is on and the transfer actually occurs at 300' (200' prior to alert height). It's very scripted with clearly defined duties and call-outs, especially in the short hairs. Not a big deal (except for the whole letting an aircraft land itself in visibility less than twice the length of the aircraft) - besides that, it's no big deal.

This allows common procedure between our CAT 2 and 3 approaches. Since the CAT 2's require see-to-land, the Captain can be looking outside as the pilot monitoring while the F/O is still heads down flying (monitoring the autopilot). If the Captain see's what he likes prior to DH, he takes the aircraft and lands it (or allows the AP to autoland). If he doesn't take the aircraft, the F/O keeps the jet and goes missed at minimums.
Same thing in the case of a CAT-3 with a DH except the Captain's taking the aircraft automatically at 300 foot RA and going missed if he doesn't see what he needs at 50'.

FNG1

Thanks for the clarification, the question regarding fail passive, was tailor to understand the changes to CAT III having a DH. Since Im familiar with the normal CAT III with no DH, I was wondering if there was any change to fail passive/operational procedure.But you have clarified very well how everything works.

Ava Mendez

my first CAT IIIB was in the A320 at KBGR, was a non event to be honest. practiced it so much in the sim, I felt nothing out of the ordinary.

Bilsch

Do you guys ever think about the FAA Specialists that maintain the LOC/GS?

Hopefully after the nice CATIII rollout...

They are a forgotten bunch. As someone who has maintained the aircraft and ground portions, it does seem that the ground guys get little attention.

EMAW

I didn't like it at first either, but at ExpressJet we could do CATII monitored approaches. FO flys to visual contact, or missed approach; captain only takes over with runway in sight. Minimums at 100ish feet, autopilot off by 85 ft. It actually worked well, IF you know and follow the SOPs.