Continental O-200 ?

Peter Dohm wrote:
What diameter of prop can you turn at 4000 rpm?

A Volkswagen is NOT a good direct drive aircraft engine because it
produces good power at 3200 to 3800 rpm. But it's a hell of a lot
easier to put a redrive on a VW than an O-200.

Actually, 46 to 48"

The VW 1600 was used that way with considerable success in the early KR-2
aircraft. However, that only meant 60 to 65 HP with the small displacement,
and the modestly oversized cylinders which would be fitted without fairly
radical case machining provided only a very modest addition of take-off
power. Cruising speed was only about 115 kts within the thermal capacity of
the stock heads--which has been discussed previously in this NG--so pilots
who were heavier or wanted to fly faster sought more oomph.


Since VW engines in race cars and hot rods (sand rails, etc) operate
under continuous power at higher power settings than this (I have
driven Bugs up tall mountains in 90 degree weather at 25+ inches Hg at
3000-3700 rpm for as long as the mountain lasted, which was longer than
enough to heat the head all the way through) this thermal analysis
theory is flawed. The 356/912 Porsche has a head not much bigger and
they run for hours on the Autobahn flat out.

The difference is these engines have a cooling blower, where most
aircraft installations run them as free cooled engines.

Free air cooling and direct drive are simple. In the old A-65 and the
airframes it went into that worked okay. But the time has come to
recognize that for an airplane to not be something looked on as an
antique, it needs a liquid cooled engine with a flywneel, redrive,
single lever power control and enough power to haul fat people and lots
of crap out of high and hot fields with healthy margins to spare.

On 19 Sep 2006 18:59:35 -0700, "Bret Ludwig"
wrote:


Peter Dohm wrote:
What diameter of prop can you turn at 4000 rpm?

A Volkswagen is NOT a good direct drive aircraft engine because it
produces good power at 3200 to 3800 rpm. But it's a hell of a lot
easier to put a redrive on a VW than an O-200.

Actually, 46 to 48"

The VW 1600 was used that way with considerable success in the early KR-2
aircraft. However, that only meant 60 to 65 HP with the small displacement,
and the modestly oversized cylinders which would be fitted without fairly
radical case machining provided only a very modest addition of take-off
power. Cruising speed was only about 115 kts within the thermal capacity of
the stock heads--which has been discussed previously in this NG--so pilots
who were heavier or wanted to fly faster sought more oomph.


Since VW engines in race cars and hot rods (sand rails, etc) operate
under continuous power at higher power settings than this (I have
driven Bugs up tall mountains in 90 degree weather at 25+ inches Hg at
3000-3700 rpm for as long as the mountain lasted, which was longer than
enough to heat the head all the way through) this thermal analysis
theory is flawed. The 356/912 Porsche has a head not much bigger and
they run for hours on the Autobahn flat out.

The difference is these engines have a cooling blower, where most
aircraft installations run them as free cooled engines.

Free air cooling and direct drive are simple. In the old A-65 and the
airframes it went into that worked okay. But the time has come to
recognize that for an airplane to not be something looked on as an
antique, it needs a liquid cooled engine with a flywneel, redrive,
single lever power control and enough power to haul fat people and lots
of crap out of high and hot fields with healthy margins to spare.

totally clueless nonsense brown eyes.
aircraft have a pressure plenum. almost no aircooled aircraft engine
are free cooled engines. everything with a cowling uses the very
effective technique of the pressure plenum.

I'd suggest you learn about them.
Stealth Pilot

Stealth Pilot wrote:
snip

totally clueless nonsense brown eyes.
aircraft have a pressure plenum. almost no aircooled aircraft engine
are free cooled engines. everything with a cowling uses the very
effective technique of the pressure plenum.

I'd suggest you learn about them.
Stealth Pilot

The pressure plenum using ram air works at a given narrow range of
power settings, airspeeds and outside temperature. Ever see what
happens when a turbo Bonanza pilot at cruise pulls the power back and
puts the nose down into the yellow arc? CRACK!!!!! go the jugs!

PFM, although they had other problems, figured correctly that a blower
with well-designed thermostatic controls worked a lot better. You
couldn't shock cool one.


The old Connies, DC7s, etc. did very well with sophisticated cowlings
and high delta heat air cooled cylinder heads. But they were not
aerobatic, had a flight engineer just to run the power plants, like a
submarine, and the only sudden descents they dealt with were if they
had a cabin depressurization. If that happened they didn't bitch that
loudly at swapping out all four before the next flight-they swapped
engines all the time at the ramp with passengers watching in those
days.

If the massive death count of the Bonanza tells us anything, besides
that Beech management should have been shot at sundown on the ramp off
Webb Rd, it' s that single pilot IFR needs single lever power control.

Bret Ludwig wrote:
Stealth Pilot wrote:
snip

totally clueless nonsense brown eyes.
aircraft have a pressure plenum. almost no aircooled aircraft engine
are free cooled engines. everything with a cowling uses the very
effective technique of the pressure plenum.

I'd suggest you learn about them.
Stealth Pilot


The pressure plenum using ram air works at a given narrow range of
power settings, airspeeds and outside temperature. Ever see what
happens when a turbo Bonanza pilot at cruise pulls the power back and
puts the nose down into the yellow arc? CRACK!!!!! go the jugs!

PFM, although they had other problems, figured correctly that a blower
with well-designed thermostatic controls worked a lot better. You
couldn't shock cool one.


The old Connies, DC7s, etc. did very well with sophisticated cowlings
and high delta heat air cooled cylinder heads. But they were not
aerobatic, had a flight engineer just to run the power plants, like a
submarine, and the only sudden descents they dealt with were if they
had a cabin depressurization. If that happened they didn't bitch that
loudly at swapping out all four before the next flight-they swapped
engines all the time at the ramp with passengers watching in those
days.

If the massive death count of the Bonanza tells us anything, besides
that Beech management should have been shot at sundown on the ramp off
Webb Rd, it' s that single pilot IFR needs single lever power control.

Stupid, stupid, ignorant person.

Jerry Springer wrote:
snip

Stupid, stupid, ignorant person.


Yes you are, as you insist on proving repeatedly. Go back to your
freak show on TV you load.

Bert Ludwig wrote:
Jerry Springer wrote:
snip

Stupid, stupid, ignorant person.



Yes you are, as you insist on proving repeatedly. Go back to your
freak show on TV you load.

Pudwig, the things you write here over and over show that you are an
ignorant person. You are not smart enough to build your own airplane and
find fault with anyone that does design and built airplanes. What a
pathetic life you must live. You are not even smart enough to quote
enough of the previous message so people well know what you are talking
about. As I said YOU are a stupid, stupid person.

On Fri, 22 Sep 2006 00:46:26 GMT, Jerry Springer
wrote:

Bert Ludwig wrote:
Jerry Springer wrote:
snip

Stupid, stupid, ignorant person.



Yes you are, as you insist on proving repeatedly. Go back to your
freak show on TV you load.

Pudwig, the things you write here over and over show that you are an
ignorant person. You are not smart enough to build your own airplane and
find fault with anyone that does design and built airplanes. What a
pathetic life you must live. You are not even smart enough to quote
enough of the previous message so people well know what you are talking
about. As I said YOU are a stupid, stupid person.

he certainly hasnt realised why I use the brown eyes comment :-)
Stealth Pilot