B737 Rapid Depessurisation headset or speakers on?

[A37575]

Question re use of headsets on during emergency descent after rapid depressurisation. My understanding is that the correct procedure for establishing communication once the oxy masks are on is to use the loud-speakers for comms between the pilots. On recent sim session the instructor required that headsets should be used over the masks. Is there a correct answer? Or is it left to the captain to decide the policy?

[Flying Wild]

My company SOP is for headsets to go back on once the Oxygen masks have been donned. It's pretty noisy in a rapid depressurisation, so you'd could be hard pressed to communicate over the flight deck speaker.

[Amadis of Gaul]

Crew's choice with us.

[Skyjob]

For those who are wearing ANR it would make a lot of sense to put back on their headset, the Telex wearers among us may not get its benefit though.

In light of the amount of crew wearing ANR I think it would only make sense not to use the speakers.
Also it can be extremely noisy and flight deck compartment speaker may not be heard as well as a headset speaker located a few cm's from your ear.

[RAT 5]

Some one many years ago asked the question, "is there enough air pressure at high FL's. for the speakers to work effectively?" I never heard an answer. Perhaps those of us who are more knowledgeable about the physics of air molecules might have the answer. Those ex-miltitary who have experienced decompression training might know for fact.

[Andrewgr2]

No problem hearing the radio speaker or audio vario in a glider at FL300, so I don't suppose a decompressed flight deck speaker would be any different

[Flying Wild]

The sound of air rushing past the cockpit as the aircraft descends at MMo/VMo to FL100 could impact somewhat on speaker effectiveness.

[ElitePilot]

I don't see any problem hearing the speakers on a rather tasty high speed descent approach why should it be any different unless you've lost one of the flightdeck windows for example?

[Bergerie1]

Some people who have experienced a rapid decompression have reported they couldn't hear anything because the pressure sudden change had rendered them temporarily deaf. Just a thought.

[bubbers44]

We all have quick donning oxygen masks to insure an immediate emergency descent can be initiated with oxygen to remain alert without delay.

Please don't complicate matters with which sounds better, speakers or headset. Just do memory items and descend until you have time to deal with other items.

[Denti]

Isn't step 2 "establish crew communications"? In that light it is not quite unimportant if one crewmember can hear the other.

We use the headset after the mask is on.

[Rick777]

The speakers need to be up so you can hear if the headset gets knocked off or has to be removed to get the mask on. It only makes sense to put the head set back on when you get a chance.

[galdian]

RICK777 hit the nail on the head.

In my present organisation guys come out of the SIM with a "touchy, feely" mentality where they will calmly:
- move the headset to around their neck;
- place the mask on and select "mask";
- return the headsets to ear positions;
- establish comms.

Whilst I have never had one I can only imagine in the worst case situation - explosive - I suspect getting the mask on could well see the headphones go flying.
As a discussion point about this during training I suggest always setting the loudspeaker volume to a high setting (assuming presently "off") and in a depressurisation select both "mask" and "speaker", that way comms will be established in any circumstances; if not required, when time permits, deselect "speaker".
I am told some SIM Instructors discuss this, some don't. Inconsistent.

Bubbers44

I'm sure your procedures acknowledge this, only mention as in my present organisation certain "poetry" has evolved in the Rapid Depressurisation Memory Items so that after the cabin is uncontrollable the PIC apparently states "emergency descent".
Discussing this with some new trainees I have seen them stop the Rapid Depressurisation checklist - start the Emergency Descent checklist - with the intention of returning to the final items of Rapid Depressurisation....assuming they remember and/or other distractions don't occur.

When discussed that the most important thing is (after cockpit crew oxy on of course) is pax oxy on....either through the auto system OR guarenteed by manual backup.... by completing the one checklist first BEFORE moving on to the Emergency Descent Memory Items - well I THINK they finally get it but I do sometimes wonder.

[bubbers44]

aiI was only in one emergency descent when my windshield shattered in a B737. The captain put on his oxygen mask and did an emergency descent talking into his oxygen mask but he had pulled out the mic cord so couldn't hear him.

I put on my mask and got a descent clearance telling him our clearance and that I was doing the checklist.

It wasn't textbook but all the important things got done.