Aviation fuel has been steadily improving, and that improvement continues today with the potential development of unleaded aviation gasoline to reduce health risks.


Bob Teter writing in Air Facts Journal, makes the following points:
  • Higher octane fuel allowed higher compression ratios with greater horsepower without increasing the engine size.
  • In WW2, the Allies had access to relatively inexpensive 100/130 octane avgas (The first number is the lean mixture rating, the second a richer mixture).
  • The Germans - 91/100 with some 95/120.
  • Japan- 87/91 octane.
  • Some piston engine aircraft currently use 100LL avgas containing a lead additive- an alternative is being developed.


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