FWIW, 15 minutes to descend from 35,000 feet to a breathable atmosphere is a very gentle descent by emergency standards. That’s a little over 2000’ per minute.
My buddy who flew Lear’s for a living until retiring spoke of his one and only ‘sudden’ decompression: he was flying a medical patient from the Bahamas up to NY. They were up there over 40,000’ ASL. Some sort of air pressure valve that pushes compressed air thru a transfer fitting failed, and the cabin air was rapidly escaping.
They had to rapidly descend to a FL so the patient could breathe, but that put them in a tough spot due to the increased fuel consumption at lower altitudes.
He said they landed in VA with a little less than 10 minutes of fuel remaining, FAR into his 45 minute reserve.
Yikers.
And yeah, he already had his mask oni since they were flying well over 40,000 feet ASL.
It might have been less than 15 minutes. All I remember is it felt like we on the hill of a roller coaster going down as fast as possible for a long time. I did not time it. There were some folks, especially the young girl across the isle, who were crying and very scared. I remember teaching the people around me how to equalize the pressure in their ears like I had learned in scuba class.
When the cabin depressurized we were right around the ND/MT border. Once we dove and leveled off they originally talked about landing at Miles City, MT. However, they did not think the runway was long enough. At that point we were only about 1/2 way through our flight so we still had plenty of fuel. So, we flew on at low altitude to Billings.
Once we were on the ground and the plane came to a stop on the runway the pilot/copilot came out of the cabin. The pilot took a big breath. Everybody on the plane stood up and started clapping out of relief.
The captain said the masks were working in the cockpit but they did not deploy in the passenger compartment. Thus the reason for the rapid decent.
I was about the third person in line once we got in the terminal. The first two got a direct flight to Spokane on turbo prop. Me and two other people got on a Continental flight to Denver and a connecting flight to Spokane. United gave us a voucher for dinner. The rest of the people were put up in a hotel in Billings for the night. I guess I could have gotten a free roundtrip flight anywhere United flew if I had really wanted to. The thing is United never offered us anything. Nobody ever contacted me even to say, I am sorry. I guess they were probably worried about a lawsuit.