On the "801"
This is an accident waiting to happen. The motor mount is incorrectly
designed with un triangulated bays and bent tubes in tension and compression.
The firewall forward weight is at least 450 pounds aluminum block or no
aluminum block. No mention is made of beefing up the fuselage to take the
vastly increased bending loads during landing and high G turns not to
mention the increased bending loads on the wing spars. Zenairs are not
over designed to begin with having very thin skins.
"The fuel burn is better then expected though and I am presently
confirming the JPI 450 for accuracy. Cruise @ 11,000 msl is producing
5.9 0 -6.3 gallons an hour."
The numbers quoted above shows a lack of understanding about engine
engineering in general. The fuel burn quoted at 6 gallons an hour
or 37 pounds an hour means the engine is only generating 83 HP giving
it the benefit of a BSFC number of .45. In the unlikely event the BSFC
is as low as .40 the HP then would be 93 HP at the absolute maximum.
Now you have a 450 pound firewall forward weight putting out 93 HP at cruise.
Something is seriously wrong.
"The numbers I am shooting for are one pound of engine weight for each
horsepower and a small total engine profile that will fit in most airframes."
What he is saying here is he things he is going to get 350 to 400 HP
with a 1.43:1 PSRU ratio. With a 2600 RPM prop that is 3700 engine
RPM. No way is that going to happen.
This person is totally clueless.
I am really worried here. Probably one of the most dangerous airplanes
I have seen in a very long time.
Paul Lamar
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I don't know who this "person" is or what his qualifications, but..
I am compelled to answer his hatchet job on every topic.
My project is a one of a kind. I had no group, forum or any other source
to go to during the design, and test flying of my experimental aircraft,
so all the calculations, fabrications and installations are a one off
and done to the best of my ability using past life experiences from
fabricating stuff on race boats, cars and god only knows whatever I
have modified in earlier years.
I built my plane, 3000 + hours of MY time. I didn't but a half built
one, or a completed one to use a test bed for my powerplant. I have
been flying for almost 30 years and owned several other planes.
My experimental plane has been flying for 5 years and 300 hours.
Been flown in air from 97f to -37f. Has over 500 landing, been flown
from JAC, 6430 msl to 18,000 feet, full throttle, !! over a couple of
dozen times to test it for strength. Been flown in all other power
settings to comfirm and quantify data. Tested to +3.5g's to - 2.5 g's.
Flown to OSH and back... not trucked there as others seem to do
to display their creations.
My responses..
1- When is this " accident" going to happen ??
2- The mount is designed by me using triangulation, just go to my
web site and look at the pics.
3- There are NO bent tubes in my mount. there are intersecting
angles but that happens on ALL mounts. At those intersections the
area is beefed up internally. Just because you can't see it doesn't mean crap.
4- I know EXACTLY what it weighs. I don't guess like he seems to.
And it is less then his "estimation"
5- Of course I beefed up the airframe as I built it. Just because I
didn't state that on my website should not give him a pass at a free shot.
6- Zenith Aircraft seem to be an "issue" to him. Mine has twice
the "suggested" HP and still has not broken in half.
7- The plane has so much power that at cruise I can throttle back
to ALOT.. A 801 has alot of aerodynamic drag. I can run 90@ 6.4 GPH
or 110@ 17 GPH. The plane hits a brick wall so why burn three times
the fuel to go a little faster. If I wanted to go fast I would have
built another type plane. You would think a guy like him could draw
a simple conclusion.
8- I have probably built, raced and tested more engines hen he can dream about.
9- BSFC of .45 ??? Jeez. I would be embarrased to tune a motor that rich.
10- Nothing is " seriously wrong"............. I am seriously throttled back.
11- The motor is capable of 600 + Hp in different trim. ie, different
redrive ratio, different intake design, etc. The motor will not gain
any more weight by changing componants, so 350-400 Hp is a no brainer..
On MY plane I purposely stayed with 1.43-1 because it for sure doen
not need any more power.
12- Where did he get the 3700 RPM # from ? I turn the motor alot
higher then that on take off. Yeah, the prop is kinda noisy but nothing
worse then what noise a seaplane makes with a large diameter prop.
13- """ Totally Clueless""" Ya wanna bet..
And in closing all I can add is
" I am really worried here. Probably one of the most dangerous airplanes
I have seen in a very long time. "
Geez... Where was he 5 years and 300 hours ago ??????.
Ben Haas.
Where are the "facts"?
What manifold pressure and RPM do you run?
"Less"? How much less?
"More"? How much more?
"ALOT"?
What is the real BSFC?
What does the engine weigh?
At 17 gallons an hour at .40 BSFC giving you the benefit
of the doubt as far as leaning goes you are seeing
265 HP max not 400 HP. I can believe 265 HP at 17 gallons
an hour.
I don't think you understands what trangulation means.
Here is the pictures from your web site. Where is the
diagonal in the first bay?
How and where did you beef up the fuselage?
What is the empty weight of the aircraft?
Paul Lamar
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