there has been an octane rating change in the fuel.
PLovett,
Would you care to elucidate on that one. The ASTM standard has not changed as far as octane is concerned for 100/130. 115/145 ceased to be available years ago.
100LL has less TEL in it now, but with higher octane base stock, the effective octane is the same, even though we have sadly lost some of the be benefits of higher TEL fraction.
CASA got it wrong, Lycoming don't know what they're talking about
Back Seat
Actually, you left out ATSB, otherwise a fairly accurate summary. Have you actually read the Coroners report??
A number of claims in the original ATSB report were chemical and physical impossibilities.
What some of you dim sods don't seem to realise is that running "high RPM, low boost" as the norm is all a bit new, and the suggestion that you
wouldn't run an engine "low RPM, high boost" would really raise an eyebrow from those who learned their trade when big pistons ruled the roost.
It is interesting to read a Lycoming engine manual from the '50's/60's, (or Continental) versus "newer" editions, to realise that even the manufacturers are short on "corporate memory", and the lawyers reign supreme.
Sadly, the most common method of leaning I hear around clubs and schools actually maximizes the threat of detonation.
Tootle pip!!