LOP operation

Roger,

I'm especially interested in the experience of anyone doing it
with a fixed pitch carb engine with single EGT and CHT probes.


How would you know you're LOP on all cylinders with that kind of
set-up? Our Tobago (O-360) will not run smoothly LOP. I haven't tried
to enhance smoothness by adding carb heat, which some say helps even
out fuel distribution.

--
Thomas Borchert (EDDH)

Thomas,

How are you, Sir? Hope things are going well.

I so enjoy the nay-sayers to LOP operation and get a lot of laughs out
of their remarks and repeated recitation of OWTs. It's funny how many
people are content to rely on myth rather than data. Ah, well.

Just finished 10 days of flying a Cessna 206 in Belize for LightHawk
in support of environmental research and data collection. Fuel there
is about $4.25 U.S. per gallon, so on top of 90 degree F temps,
keeping the fuel burns minimized is one of those very high priority
items in one's operating plan. Plus, one may only purchase fuel at
one airport in a country the size of the U.S. state of Mass.
Therefore, GAMIs and LOP ops are essential. I very much appreciate
the fact that when I've got the rear doors off the 206, with
photographers hanging outside, I'm able to maintain the requested 85
knots indicated with the cowl flaps closed and CHTs in the 350 degree
F range. If I go ROP, the CHTs hit 400 degrees F immediately and even
opening the cowl flaps, which adds a bunch to drag at those speeds,
and requires a power increase, doesn't cool things off much. When I
can burn 11 gph in that IO-520 at 24 inches and 2200 rpm LOP while
keeping the engine very happily cool in the tropical heat, I just
shake my head in wonder at those who still don't get it. Plus, even
with the questional quality control on the cylinders, that engine is
running clean and doing a very nice job of hanging in there in terms
of an absence of gunk in the various areas where you get the products
of incomplete combustion in ROP operated engeines.

Warmest regards,
Rick

Thomas Borchert wrote in message ...
Roger,

I'm especially interested in the experience of anyone doing it
with a fixed pitch carb engine with single EGT and CHT probes.


How would you know you're LOP on all cylinders with that kind of
set-up? Our Tobago (O-360) will not run smoothly LOP. I haven't tried
to enhance smoothness by adding carb heat, which some say helps even
out fuel distribution.