PPRuNe Forums - Light aircraft down near McKinlay, Qld

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- - Light aircraft down near McKinlay, Qld (https://www.pprune.org/pacific-general-aviation-questions/655646-light-aircraft-down-near-mckinlay-qld.html)

Quote:

a B200 Kingair operated by an RAAF pilot (who had had several previous hyperbaric chamber hypoxia training sessions)

Not to forget F-18 A21-41 that flew from the Tindal area and crashed 100k NE of Weipa, crash site found after three years.RIP FLGOFF Cameron Conroy

43inches
The 737 crash you allude to was actually Helios Airways, based in Cyprus, with a German captain in command. The aircraft had German registration. Small point, I agree, but necessary clarification.

"I always thought after the Bourketown king air ghost flight, if someone's garbling on the wireless everyone should be yelling put your oxygen on now. Reckon it'd help?" It certainly couldn't hurt in my opinion & to a small degree, I'm a little surprised ATC don't have procedures for something like that following the "Ghost Flight" accident in 2000 & the VH-TAM incident where both pilots were making unusual statements (including garbling or slurred speech).

When I first flew the C441 Conquest back in 1989, the guy that did my training said the two new things that will "bite" for flight above 10000ft are ice & hypoxia. Unfortunately he is/was 100% correct...

ps yes, Helios 522 was the B737 pressurisation accident...

During all of my hypoxia chamber runs, despite expecting it, I never once decided it was time to mask up. Despite being told to - and I have no memory of that.
Once I even tried to stop the doctor from putting my mask on for me.

My experience has alerted me to my initial symptoms whilst flying twice. The training is worthwhile.

I flew a couple of models of Turbo Commander. It was SOP to turn off the O2 bottle (in the rear compartment) after each day or night of flying to prevent loss through system leakage. Easy enough to forget to turn back on.

Not implying that this is what occurred.

The pressurisation in a few that I flew was woeful. A combination of tired air cycle machines and issues with the underfloor tubing that delivered the air would often mean a 17,000' cabin at 25,000'. And that was with Hot Air temp on full. It was worse with cold temps selected.

17,000' cabin altitude. Wot cood possiblie go rong?

Quote:

Originally Posted by Noeyedear (Post 11594218)

A combination of tired air cycle machines and issues with the underfloor tubing that delivered the air would often mean a 17,000' cabin at 25,000'.

So No Idea. How did that work out for the passengers and crew?

Quote:

Originally Posted by Noeyedear (Post 11594218)

If the 695 pressurisation system is anything like the C441, there is a real trap when cold air is selected. The ducting can slowly become blocked with ice in one of the filters. Pressurisation is normal in the climb, but at altitude there is a subtle loss of cabin pressure as inflow reduces.
This nearly killed me on a long distance ferry flight. It was only from experience in the dreaded hypoxia chamber many years before that I recognised my symptoms in time to get the oxygen mask on. Another 20 or 30 seconds and it would have been lights out.
I wrote an article on this many years ago. In the analysis, an expert explained my failure to spot the warning light (no aural alert) as tunnel vision which is also a symptom of hypoxia. I remembered blue fingernails and dizziness, inability to concentrate, euphoria etc, but not the vision impairment effect.
A visit to the hypoxia chamber is no longer necessary for civilian pilots before flying pressurised aircraft; maybe it was never mandatory? It should be, particularly for single pilot operations - it’s more relevant than some of the other stuff we now have to do.