Hi Again,
I stumbled to this when checking out newest avweb newsletter:
http://cafefoundation.org/v2/pav_pavchallenge_studies.php
They have a design competition - and for all the right reasons. They try
to press the costs of flying down.
Check out those pdf's, there's some very sensible points and neat design
innovations. Eg. concept of FAA-certified stock auto engine! No rotary
insights there, but that's excusable. Definitely worth reading.
Cheers,
Petri
Engineering student
Helsinki, Finland
btw. on holiday now, i'll get back to that hi-power rotary thing next
week.
CAFE is OK but these NASA people don't have a clue. They are advocating
a 3900 pound, four place airplane powered by a 300 Hour TBO Chev V8 shaft
driven
ducted fan. Obviously they are aviation history challenged.
Perry Mick http://www.bridgingworlds.com/duckt.htm
gave it an excellent try for a lot of years and wound up installing a
gear box
and prop and went 20 kts faster for the same fuel burn. If I were the CAFE
and EAA people I would disassociate myself from NASA as it is ruining the
CAFE's
credibility. Dozens of ducted fans have been built over the last 50
years with the same bad results. Kuchemann and Weber identified the
problem
in their book Aerodynamics of Propulsion published in 1953 page 134.
A new Chev V8 project shows up at OSH every year for the past 20 years
and it is gone in a year or two. They self destruct after a few hundred
hours.
A whole lot of people dumped 50 million dollars U.S. into the Orenda big
block Chev project
over a 30 year period and wound up going bankrupt or out of business. They
changed every
part except the bore spacing and V configuration. What they should have
done was design
and build a horizontal opposed version from scratch. V engine are heavy
because they
are trying to force the crank into the oil pan.
A company in Midland Texas called Trace http://www.traceengines.com/
bought what was left.
The 500 HP continuous... 600 HP take off engine weighs 750 pounds and they
are
asking is $250,000 dollars U.S.. For that kind of money you can get
a PT6. Hope springs eternal.
In the mean time Dave Atkins has flown his Mazda rotary powered RV6 from
Seattle to OSH
for the last 13 years straight. Tracy Crook's record is almost as good
from Bell Florida to
OSH except for this year. I see Chuck Dunlap in his rotary powered RV6
from Arizona at
Sun n Fun and OSH almost every year. Other Mazda rotaries in aircraft have
hundreds of hours.
Problems are never the engine. This year a four place two rotor powered
Velocity
went 205 MPH in the Dayton to OSH race burning only 12 gallons an hour.
It would be nice if the CAFE foundation and NASA helped out the rotary
community by
developing the turbo compound rotary engine.
http://www.scanlab.fi/docs/docs_index.htm
NASA_1994029727.pdf
http://www.rotaryeng.net/turbo.html
How about it Brien Seeley and Paul MacCready?
Paul Lamar
Several years ago at OSH two NASA guys gave a forum on auto engines in one
of these planes and arrived at the conclusion that a V8 was the best choice.
Paul and I and a few others in the audience asked about the rotary and they
replied that they did not even consider the rotary. They also did not know
that another NASA center had one installed in a Cessna mixmaster ready to
fly when the program got canceled. There is no collective at NASA. It is
a bunch of different centers fighting amongst themselves and nothing gets
done.
Joe Berki
LimoEZ
It was the same guy and the same silly 3900 pound Chev V8
shaft driven ducted fan powered airplane. Mark D. Moore. In five years he
has produced several Power Points presentations and half a dozen pdf's.
Now they are trying to get somebody to produce it by offering a $250,000 prize.
Nobody with the where with all is dumb enough to build a turkey
airplane like that because it has zero commercial potential.
Airplanes are about three things. Weight, weight and weight.
Paul Lamar ...No rotor no motor.
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