Hobbs

Morgans wrote:
"Dave S" wrote

Running the engine on the ground for 40 hours may give you 40 hrs
hobbs time but 0 hours flight time. Having the hobbs wired to the
master could also pad the time significantly, without the engine
even running. Someone could sign off the books and nobody would be the
wiser.. but
you'd only be cheating yourself, if you took your family/friends up
in a plane that wasn't shaken down properly.

Also add that in those 40 hours all systems are to be checked in all
possible circumstances and all different parts of the flight
envelope. The plane is supposed to be evaluated to see what the
limits of the flight envelope are, and an operation manual written,
with all of the applicable V speeds logged in said manual, and
emergency procedures written.
For planes like the RV that have thousands of copies flying, that
might not be too hard to do, but for a plane that is a one-off, or
only has a few copies flying, and likely with different engine and
prop combinations, and with who knows how many slight variations, I
would think nailing down one of these rare airplanes would need all
of the 40 hours, to do the job well.

The FAA has a really good guide for phase one testing. But, so many of the
systems to be checked when following that guide don't exsist on the plane
I'm building that I will be flying a bunch hours inside that 25nm circle
after everything has been tested. Not that I have a problem with that but my
particular 25 nm circle is a little boring. I really kind of wish there was
a 3 phase program. Phase 1 as is, Phase 2 larger or unlimited area without
passengers, and then Phase 3 which would be like the current Phase 2.