Cruise RPM setting

If John needs to log 100 more hours to get his Commercial, and he's
paying $100 an hour dry Hobbs time, the airplane cost is $10,000. If
he burns 12 gallons an hour of $4 avgas he'll spend $4,800 on fuel --
if he does it at 7 gph $2,800. Crank in your own numbers, of course.
As those Wentworth commercials on TV say, "It's your money, use it
when you want to." Saving a couple of thousand dollars might be a
worthwhile consideration.

With respect to going to new and interesting places? Sure, but in
terms of learning good flying techniques, don't you think slower is
better than faster? Cross winds, airplane control, all of that matters
at least as much as flying into a new airport. My favorite pilot,
during his BFRs and check rides with his friends, doesn't often
demonstrate straight and level, but slow flight (I hate a Mooney's
attitude when he practices slow flight at 25 square, hanging that
thing on its prop.)


On Oct 14, 7:26 am, kontiki wrote:
Thomas Borchert wrote:
Your objective of saving fuel and prolonging flight time is unusual for
a renter. Still, if I were to build time with a rental aircraft and
cost would be the same regardless of power settings, I would GO to
exciting new places at the fullest speed available rather than dawdling
around in the area I know. With respect to time building for a
commercial, that tactic would be immensely valuable since it would
expose you to new terrain, different weather and unknown fields. So,
again, if cost remains the same regardless of power setting, IMHO you
might want to rethink how you build time. I would even suggest a
multi-day cross country to an area of the country you always wanted to
go to.

As a general rule, I normally use the maximum recommended cruise power
setting from the POH, since I normally want to go somewhere. That's
mostly 75 percent. I use best economy mixture if I have a tail wind and
best power if I have a headwind. Also, I use as low an RPM setting as
possible for noise reduction, but I have a choice, since my airplane
has a constant speed prop.

I would say this is very good advice. I would much prefer to go
somehwere and visit new and different airports to gain experience
not just mindlessley logging time for your logbook. The goal of
the 250 hours for the commercial is for you to gain flying
experience and build skills.

A few nights ago I flew with a student in a 152 on a night
cross country and didn't get back till 11PM. He chose the 152
because it was cheaper per hour. When we got back I was able to
demonstrate that by flying the 172 which is faster and rents at
a higher rate per hour would have been pretty close to the same
amount of money. And no, we didn't need to go slow just to make
XC for his logbook.- Hide quoted text -

- Show quoted text -

Tina,

and he's
paying $100 an hour dry Hobbs time,

As I said, my remarks hold only if cost is independent of power setting.
Dry rentals are very uncommon, AFAIK. And I overread his remark that he
is indeed renting dry blush. Sorry!


Sure, but in
terms of learning good flying techniques, don't you think slower is
better than faster?

Not at all. Both is important, IMHO.

--
Thomas Borchert (EDDH)