wrote:
To AF retired, my experience? I was a jet engine mechanic AF43250, so I know
what I am talking about. As far as the cold section of the engine it has
what is called a convergent-divergent duct system to compress the air to 70
parts oxygen to one part fuel, however the engine can't use all the air up
to approximately 80% power so it exhausts it thru the bleed valve on the
side of the engine.

J-33s had bleed air? Please explain to me the J-33 used "convergent -
divergent" air flow.


Again, check any engine guide and gasoline engines have
approximately 14 parts oxygen to 1 part fuel, doesn't matter how its
compressed. The fuel control controls the amount of fuel injected into the
engine but it relies on pressure sensors and temperature sensors to do that.
Using avgas the egt would go very high because of its quick burning
characteristics compared to kerosene or other jets fuels therefore the
pressure and temperature sensors would send that information to the fuel
control for adjustment. The fuel control also is lubricated by jet fuel and
would soon fail without this lubrication ( it is so critical that we had to
submerge the fuel control in jet fuel for 24 hours prior to installation and
then if we manually moved the controls more the three times prior to
installation we had to send it back for rebuilding.

The lead in AvGas would have acted as a lubricant long enough to get
where you were going.

Incidentally, I also
worked on F-102.T-33,B-57,T-39,C-130,C-133,F-101,all the aircraft had the
same requirements for fuel.

When you get a chance look at the -1 TOs for those aircraft. They
list substitute fuels. A lot has changed since you were in, I'm assuming
1960ish, but fuel characteristics.

You worked on all those aircraft in less than 6 years in the USAF? It
took me 20 to do the aircraft I listed.



Perhaps the more modern engine have more
tolerant materials , however when talking to recent jet engine mechanics
they say the requirements are the same. As I understand it the aircraft you
flew on used the jets for takeoff and at times at altitude only, if that's
truly the case the engine may be able to operate on avgas at those times and
those times only.

Do us both a favour and do some research on the subject, OK? Try
Google. Telling me I don't know what I am talking about doesn't quite
make for civil discourse. BTW, I never said I flew on B-36s or C-123s.

Dan, U.S. Air Force, retired