You don't set a rate of descent. You basically close thrust ( open descent on the Bus ) and then the Elevators control the speed that you have selected. Therefore the rate of descent will vary.

Would love to know right now if any windows in the cockpit had been replaced

We will see what role O2 played once the FDR is found and readable - should be today. Perhaps the holes in the cheese did line up: Structural failure and insufficient/no O2 supply.

Yes if the descent mode (OP DES) was pitching the nose up/down to maintain a selected MN/IAS. As the head/tail winds change during the descent the pitch attitude (and vertical speed) will change to maintain the selected speed.

I was thinking the same thing, i was also thinking that maybe the decompression occurred in/near the cockpit leading to other reasons why the pilots were incapacitated

All these decompression/pressurisation ideas are all well and good.
However, they do not explain why an experienced flight crew would then go and select a FL below 10,000ft when they know they are over the Alps and make no course alteration whatsoever before then becoming incapacitated.

This makes no sense to me.

O2 in the lavatories
 

This seems a suitable occasion to re-float a question that I tabled about one month ago (and subsequently modded out) - Garuda domestic are currently issuing instructions in their safety briefings that in-toilet O2 systems have been removed from their aircraft (738) and "in the event of cabin depressurisation, please return to your seat and use the overhead O2 mask".
These systems were removed apparently as the result of an NTSB(?) directive a couple of years ago, that directive since reversed - but not by Garuda.
I wonder how many other operators removed those systems world-wide?

As for the concept of the crew member in the toilet at the time of de-compression returning to the flight deck with the O2 bottle and mask, I doubt that would be possible even if the aircraft does still have the system installed.
Not unless he has oven gloves available.


However, back to my unanswered question. What is the likelihood that a person could actually make it back to their seat (or back to the flight deck) from a lavatory with or without O2 system installed.
We will presume that said crew member was in a fully-clothed condition when the de-pressurisation occurred.

The answer is: zero likelihood - you stay there with the mask on until at a reasonable altitude...

Maybe the Alt selector was in the 1000's range, wound it down to get the descent going but incapacitated before being able to fine tune them on the second loop

@Liveryman

The AB procedure is to initiate the descent first and then when established in the descent set the appropriate altitude.

If on oxygen this should work but if not.......

last a/c I flew was b767. before starting engines ck list we always checked emer o2 set 100 per cent and push to test while watching bottle pressure. first flight of day, don and restow.

o2 is a very important emergency system and very much respected by professional pilots.

many rules re o2.

far 121 requires single pilot on oxygen if other pilot leaves crew position above fl250. europe similar.

Nope, not similar in europe. There is no such rule since JAR OPS came around, up to FL410 nobody needs to sniff oxygen if the other leaves the flightdeck.

I would not be surprised to hear that a recommendation would be made for one flight crew member to be on Oxygen at all times above 10000". Following the AirAsia and MH370 it wouldn't be just airbus a/c.
Pretty uncomfortable for LH and I guess more O2 required.:sad:

Never understood why you wouldn't just set FL100/MEA in the window straight away instead of setting something to come back and fine tune later. A few extra clicks is adding fractions of a second and by that time you should be on oxygen having completed the most vital and time critical memory actions anyway.

Unlikely, I would venture, since the everyday impact on SA and crew comms would create more issues than it would resolve.

Well that is just wrong. Unsafe and illogical.

Yep - I my daily work I decided for myself to discard that piece of the procedure and always set a safe target on the first loop for exactly the reason, that there is a risk of becoming incapacitated. Usually its FL100 but before entering higher terrain I will brief my "first target" to the chap next to me...

I regard the current procedure as dangerous...

That seems the most reasonable thing to do to me. Any other way seems to invite mistakes and possibly less healthy results!

Can anyone with Airbus experience let us know how many "clicks" the alt knob gives you in say half a turn - a quick flip? Even on 1000ft/click, I find it strange that you'd get 30 or more, as some seem to be implying. How on earth would you be able to set an accurate altitude?