The m20J is pretty slippery already and when it was introduced in the
70s was a big step up in efficiency in a production airplane.
Homebuilts do do an even better job of cleaning up aerodynamically.

The little seals on the flaps and so on were lipstick, the real gain
over the Mooney Executive had to do with the 201 getting a more
aerodynamic windscreen and engine cowling.

We have no serious complaints at all about the airplane (well, in a
rainstorm getting in without getting the seat wet is difficult,
checking the fuel is hard on pantyhose sometimes) but finding a couple
more inches of manifold pressure would be very handy when trying to
get to 12000 feet quickly. Once there, we can sip 8 gallons an hour
and move along pretty well.

I think using ram air would not increase aerodynamic drag, B. Instead
of having the air moving at the airplane's airspeed plus prop induced
speed impacting the cowling, it could in fact be going into a hole.
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 better leave that to the engineers.




On Jun 1, 7:57 am, Bertie the Bunyip wrote:
Tina wrote in news:f9933f5e-0c1d-464b-a1d8-
:



The Mooney 201 has a ram air port, a half a foot under the prop
spinner. The POH tells us it can be opened at altitude for a very
modest increase in MP and we find maybe a half inch increase in
pressure. The idea of the thing is, if the port is looking right at
the air being thrust toward it by the prop (it can't be more than 6
inches or so behind it) as well as the air impact from the airplane's
motion the air being 'rammed' into it should effectively lower the
altitude the engine thinks it's at. Well, a half inch of Hg is about
500 feet or so. The question is, though, wouldn't you think there
would be a way to capture a great deal more of the ram air effect and
really boost the engine performance? Who wouldn't like to fly at 24
square at 12000 feet without a turbo charger?

What makes me wonder about it is, even at 60 mph holding your hand out
of the window of a car subjects it to a significant backward pressure,
so the energy must be there.

Didn't know any production aircraft had that. Well, to some extent
almost every lightplane does . that's why the carb air intake faces
forwards in most of them.Everything is a balancing act with an airplane.
More air = more drag. You could try putting a couple of woks with tubes
out the back to boost your MP, but you're going to pay for it. !Moooney
must have spotted an area of the cowl that would not penalise you in
this way and decided to utilise it. Really clever homebuilders do a lot
of this kind of stuff as well as, and probably more more importantly,
dealing with cooling drag.
Have you put the other speed mods on your airplane? I think there's
nearly ten knots available in seals and various other tidy it up
fairings.

Bertie