Rapid Decompression procedures?

Same as most here. Oceanic we turn 15 miles off track. Get the masks on first, determine if the cabin alt is uncontrollable, if so emergency descent. A good way to remember the initial actions is "altitude, altitude, speed, speed, speed". A couple of good turns on the ALT knob, FLCH, Idle, Speedbrakes, wind the speed up in the MCP to MMO/VMO. Go back, refine alt then run the checklist. Over the water we go down to 14,000 initially.
 
Hi folks,

Just wondering the various procedures your company abides by, which may or may not line up with any rules you have in the states in regards to rapid decompression?

I've heard anything from descent on course, to 30-45 degree turn off course then descending.

Differences between on airway or flying on an RNAV track?


Mask on.
Breathe in through the nose...out through the mouth...Repeat.
Descent like the dickens...
 
I think I may have told my story before, but I had a decompression as well. Old ECS plumbing in my aircraft often makes for some bleed/ECS related adventures. Such was the case when, after putting my ECS into manual mode due to another somewhat unrelated caution, I started getting some minor pressure cycling. Eventually brought the throttles back to idle to slow down while at 35k ft, and all of a sudden my cabin pressure dumped instantly from 12kish (normal schedule) to ambient/35k. Thought my brain was going to pop out of my head. Quickly switched back to auto ECS, and noticed that I had symptoms of hypoxia or something. Let my flight lead (and notably, I was the brand new FNG at the time) know sheepishly, and we started an emergency descent. At no point in that process did I activate emergency O2, in spite of it being bold face. Chalk it up to hypoxia related mental confusion or whatever else, but bottom line, I didn't follow the two procedures that will save your life. #1, get down immediately. I waited way too long to communicate, bring my lead into the cockpit with me, and then follow him. He should have looked out and suddenly seen no wingman because I was already bullseye nose low getting into breathable air. #2, emergency O2. No delay. Don't second guess it.....use the bottle before it is too late to use. That little omission has killed dozens of better aviators than myself. Those two responses need to be instantaneous and without question, even if in the back of your mind, you are questioning whether or not you are really hypoxic/suffering from DCS/whatever other physiological issue. Some of these considerations are peculiar to the type of flying I do, but the big boldface #1 and #2 are not. Don't ask ATC for permission, don't try and tough it out, don't think that half a boldface checklist is good enough, and don't start troubleshooting an obviously broken system before you are physiologically safe from its effects. Just my take, lucky to actually be writing this.
 
BL is, take care of yourself, then take care of the plane. You won't do the latter, without doing the former first.
 
I've had a "rapid D" in the 1900 - it was pretty much a non-event at FL250. Our standards for what to do in the freighter were essentially "Get your mask on, figure out what you're going to do." Basically, my ears popped, the cabin light came on and I reached up to grab my mask all in a few seconds. Once I was on oxygen, it wasn't really an emergency any more, so I didn't bother to declare, and I asked for lower, once I get below 12,000 I went off the mask, I was close to where I was going so I landed and had MX fix the door seal.

In the PC-12 I currently fly, our company procedures are:
Mask On
Start Down (if applicable)
Tell ATC
Checklist
 
The erj was power idle, speed brakes open, airspeed 250, gear down, and check the mea alt. Then crank the turn knob over and it puts you in a 30 degree bank at about 6k per min decent.
 
They won't do anything for smoke or fumes, but for lack of o2 pressure they should keep people alive long enough for you to get down to the mid teens where they can breath normally again.

Every jet I've flown has called for emergency descents with the autopilot on. Current airspeed if you suspect airframe damage, MMO/VMO if you don't. Also, it's always been straight ahead, unless directed otherwise by ATC.

They'll actually make the effects of smoke and fumes worse. People will hold their breath/ try to cover or filter air if they don't have a mask. With the yellow cup on, they will not try to avoid inhaling smoke. Being a recirculating diluter bag, 80% of what you breath from the bag may/will be toxic. The basic design of the planes O2 system provides enough oxygen to the mask to allow an equivalent 8000 foot atmosphere... the only problem is that the reg only pertains to the amount of oxygen, not the delivery method. The yellow cup doesn't seal, and won't provide enough oxygen above 35,000 feet, and likely will not above 25,000 feet for passenger who have been exposed to a cabin altitude near 8000 feet for at least an hour. In reality, @40,000ft, or even 45,000 feet you are not going to die "quickly" certainly not in 4 minutes (assuming able bodied)



TUC is said to be 50% of published values for passenger who have been exposed to cabin altitude near 8000 feet for durations longer than 1 hour - there is a good chance if you had an explosive D @ altitude, that none of your passengers would even have a chance to get the mask on before passing out. If they actually expected the O2 system in the plane to help/ work effectively, they wouldn't worry so much about the plane getting to 15,000 feet in 4 minutes.
 
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