"We are as surprised as you are by this circular and
are contacting ExxonMobil Aviation to address the matter. We are
unaware of the reason for this circular and we are equally unaware
of any jet fuel related service difficulties in any TAE powered
Diamond airplane. There are of course several other certified and
uncertified diesel aero engines in operation and there are also TAE
installations in other than Diamond airplanes."
Source: From a letter to owners from Diamond
Aircraft, expressing puzzlement at a letter issued last week by
ExxonMobil to its distributors, warning against fueling
diesel-engined planes with Jet-A.