On Jun 4, 7:56 am, Big John wrote:
On Mon, 2 Jun 2008 11:19:41 -0700 (PDT), "Ken S. Tucker"



wrote:
On Jun 2, 10:13 am, Tina wrote:
On Jun 2, 12:01 pm, "Ken S. Tucker" wrote:

On Jun 1, 4:39 pm, Tina wrote:

The induction port for the ram air on the m20J bypasses the air filter
as well, so we typically observe about a half inch improvement in MP.
That's in line with some of the other numbers offered here.

I guess there's no free lunch. There is no way we want to have an
IO540 pull the airplane along, nor do we want the fuss with turbo
charging. The payback for our typical for real flight mission is just
not there. My thought was and is that if it was something pretty
obvious someone would have done it on a homebuilt. Actually, knowing
some of those guys, it does not have to be obvious at all, they are
really creative designers.

Tina, I think this analysis you posted is good,
" It's only a 360 cubic inch engine turning at 2300 RPM or so. Isn't
that a demand of, let's see, at 23 inches mp at sea level that's
23/30 * 2300/2 * 360 / 12^3 or 180 cubic feet a minute? "

I see Tango 2 Denny has some interesting ideas.
Ken

Well, I think it's a dead issue for us. What is fun to think about is,
let's see, about 200 cubic feet a minute, that's 40 cubic feet of
oxygen a minute, or about 3 pounds. For 50% more O2, 1.5 pounds a
minute, or say 20 pounds to get to a pleasantly high altitude. Maybe
that translates in to dewer weighing a total of 50 pounds with liquid
O2? But it would make 15 inches of MP look like 22 or so as far as the
engine is concerned. I better get back to my day job.

Without crackin' the books and pounding the abacus,
you look like +/- 20% using BoE (Back of Envelope)
calculation, which means you get either 80% or 120%
on your physics exam, you choose.

Resolved: psychologists should not be permitted to minor in the
physical sciences. All in favor?

OR pilots should not be permitted to engage in
psychology in this group, now what's the chances
of that happening...is "nil" close :-).
Ken
PS: What's the rationale of the 12,000' cruise?
You know about the "bends" don't you, if not
just read Berties post!

************************************************** *

Ken

Have you ever talked to anyone who got the bends flying? I have
thousands of hours and never have.

I have gone to 43K+ and made supersonic dives to 10K +/- with no
problems.

I have cruised for hours at 30K cockpit pressure and no problems
during let down and landing.

Is Mt. Everest summit at ~29K?
You can get a quick overview here,
http://en.wikipedia.org/wiki/Decompression_sickness
Ken






Big John