Testing your glide. Are people doing this?

"Paul Sengupta" writes:

On my IMC (instrument flying) rating renewal last year, I took off
(not in my plane, but a rented PA28)... when I got to cruising
altitude I levelled out, brought the throttle back then leaned the
mixture. The examiner said "There's a man who owns his own
plane."...he was referring to leaning the mixture, something I'd
always been taught to do from day one of my training. He said a lot
of renters fly around with mixture fully rich all the time. Even a
pilot friend of mine commented that he never leans the mixture
because he "never flies above 2000ft".

That's an interesting observation. On my first solo cross-country in
a rented 172 during my PPL training, I decided to rent the plane dry.
I made sure the tanks were topped off, leaned properly, filled up
again at my destination (even though I'd used only a few gallons --
school policy for student pilots), then flew back and fueled up again
on landing.

When I arrived back there was some consternation, since it turned out
that the club didn't rent dry to student pilots. They ended up
reimbursing me for the fuel I'd paid for and charging me the wet fee
for the plane. The manager tried to convince me that the wet fee was
a great deal, until I handed him the fuel tickets to show how little
fuel I'd burned on my trip. He asked me how I did it, and I smiled
and answered that I'd discovered a little red knob on the panel. Note
that at that time I would not even have thought of running lean of
peak -- I simply leaned to best power and enriched a bit, like my
instructor had taught me.

I wasn't going to make a big snit, but clearly the club assumes that
renters will always fly full rich. Nowadays, in my own Warrior, I
push the throttle to full for takeoff and don't touch it again until
I'm ready to land; in-between, I set power by adjusting the mixture
only, as recommended by the POH for best economy. I figure that if I
can make my engine run cooler, produce practically no carbon monoxide
(a major issue in a Canadian winter), avoid fouling plugs, *and* save
gas, what's not to love about running LOP WOT?


All the best,


David