Day 5

I learned a lot about fuel today.

I learned about avgas, about jet fuel, about detonation, preignition, volatility, and Reid vapor pressure. I learned that microorganisms can feed on hydrocarbon fuels and cause all kinds of nasty gunga to build up in your fuel tank and, consequently, your fuel system.

So be sure and lysol your gas tank.

I learned that reciprocal engines will not run on jet fuel, but that jets will run on just about anything, including diesel. Cars will run on avgas; it's a form of gasoline.

100LL avgas (the most common avgas) contains tetraethyl lead. Cars up until the 1970s used leaded fuels. I never really knew what the lead did for the fuel. Now I do. Leaded fuel is more stable and resistant to detonation. Adding tetraethyl lead to automotive fuel allowed manufacturers to increase octane (and heptane) levels in gas, making it more powerful and stable.

Then we figured out that burning lead all of the time, everywhere probably wasn't a good idea. (So now we just do in the sky... and sometimes the water...)

Of course, I learned about fueling and defueling aircraft, as well as the safety considerations involved with that.

I watched a video from the 1960s (no shit) wherein GM engineers were trying to figure out the complexities of mid-to-high grade octane fuels, figure out the complexities of detonation and preignition, and all of that other stuff we take for granted today.

I also learned that water slugs can be entrained. And no, that doesn't sound as neat as you'd think.