Oxygen Oddities

Mounting tanks and filling with non-ABO complicate picture for supplemental oxygen

I just finished reading my May issue and I had two questions.

In “Burn, Baby, Burn” it says “the average daily consumption rate of automotive gas in 1999 was around 360 million gallons.” Is that in the U.S. alone, or worldwide? It’s a statistic I’d like to quote to (non-aviation) friends, but I want to get it right.

In “Roll your own O2 System” on page 5, when you mount the O2 tank in the baggage compartment, doesn’t that require an STC or form 337, at least? I have seen the FAA declare an aircraft unairworthy because it had a non-STC’d panel mount for a portable GPS, and this seems like a bigger modification to me. It affects the aircraft weight and balance and empty weight, at the ve...