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.