Hi,
I have a query on question 5 of the revision test No 2 from the HPL text. The question asks the most likely cause of abdominal pain caused by the expansion of gases within the body with the answer key at the rear of the book nominating the correct answer as b). a descent in a high performance unpressurised aircraft.

Is this correct? In a rapid decent isn't the air pressure going to increase from the start of the descent to the end of it. If the air pressure at the end of the climb is higher at the end of the descent and the body hasn't had time to equalise then doesn't that mean that air in the body is going to be compressed by the relatively higher external air pressure, rather than expand?

I think the answer should be a). a rapid climb in a high performance unpressurised aircraft since the pressure at the top of the climb will be lower than the gases in the body that have not equalised and will therefore try to expand.

If I've misunderstood, I'd appreciate some assistance to clarify this, otherwise I suspect it may be a typo. I have looked through previous posts and the new forum for HPL & couldn't find any other reference to this, so apologise if this is something that has been addressed elsewhere.

The answer to that question has been changed to 'a climb in a high performance aircraft'. There is an errata on the web site to that effect. Current versions of the book reflect that. Thanks for your feed-back.

Bob