In both Clarence Lee's (MAN) and Dave Brown's (MA) most recent columns, the spectre of the Environmental Protection Agency's banning model airplane engines is presented. I wrote to Lee asking how a methanol-burning engine, which, according to my skimpy knowledge of chemistry, should only produce carbon dioxide and water during combustion, could possibly be regulated. Heck, humans exhale the same gasses, (plus copious methane from the other end!) so how, I wondered, could they find fault with our little engines? Lee answered that it's formic acid they're concerned about. I'm no chemist, so I looked it up, and it seems that catylitic combustion of methane, as in glow ignition, will form formic acid.
I can see how we might have to give up on nitromethane and all use FAI fuel, but, BAN our engines? Don't those folks at the EPA have anything better to do? Would using spark ignition cure the formic acid problem? I'd like the opinions of people who actually know something about combustion chemistry to set me straight on this!
Geoff