Bellow is an email from one of our LOBO Oz members who has a beautiful twin turbo Lancair IV. As we know our aircraft are very capable of cruising in the fligh levels.
I did ask Peter what oxygen system he uses and if they were using a canular or mask at the time so not sure as yet.
Please have a read of his experience below and comment if you have had similar experience.
I have provided Peter with some very good information on high altitude flight directly from our LOBO Lancair IVP/IV manuals.
Dear Gary and other Lancair owners.
I would like to ask the group about the bends at high altitude. As a scuba diver, I know all about this with diving, but have little knowledge with aviaiton.
I have read up a bit lately.
The bends seems to occur above 18 000. It is more likely for longer duration flights, and is more common in passengers with high body fat content..e.g. women. It is much more likely in rapid ascent.
As my Lancair IV is not pressurised, it seems that the risk of the bends is my altitude limiter, rather than my oxygen blood level which I can monitor with pulse oximetry.
I flew back from Ayres Rock the other day, chugging along at 335 nts at 22 000. A passenger with psoriasis started experiencing tingling in their skin lesions, a sign of the bends. I descended to 21 000 and the tingling went away.
Does anyone have personal experience or advanced knowledge of incidents of the bends in aviation? Is there an accepted safe maximum altitude for non-pressurised flight?
Finally, has anyone heard the theory that the bends explains many of the unexplained high-altitude crashes in Lancairs?
Interested in the knowledge bank.