>> Perry Mick has a turbo engine on a test stand and
>> he would like to test the LAEV prop. Here are
some pictures.
>> This was a joint design and build effort of the
ACRE.
>> Butch machined the mechanisim and Perry built the
blades.
>> It is a cockpit adjustable pitch prop.
>>
>> Yes, the engine on my test stand is 1988 turbo.
Probably only
>> around 200HP, not 250. The prop blades were built
for tractor
>> reverse rotation.
>>
>> I'd like to test the prop and blades as is, then
>> perhaps build a new set of blades that I can run
on
>> my plane, which would still be 2.17 ratio reverse
rotation,
>> but pusher instead of tractor.
>>
>> Paul Lamar ...No rotor no motor.
>
> The prop looks good.
>
> Pardon my ignorance, which I am trying to fix, but
what is LAEV
> and ACRE?
>
> Doc
>
> I am not sure what LAEV means. Somebody made it up
> a long time ago.
>
> ACRE is the Air Craft Rotary Engine.
> --
> Paul Lamar ...No rotor no motor.
Paul,
Butch suggested it was Lamar Aircraft Electric
Variable ( Prop)- from
memory. Although the concept needs proof, it's quite
obvious that it's a
strong economical unit.
For those that don't know Butch he's an Aviation
Engineer still working for
the US Government, no matter how hard I try to get
him to give it up and
concentrate on the Rotary program. I think he likes
the challenges!
Either that or he's a masochist, either way when
your on the top of the pile
it hard to give it up - I guess!
George (down under)
--------------------------------------------------------
It all started way back around late 1998, 1999 or
2000. I am not
sure as I am going on some of my old part dwg dates.
I would have
to go back to the old CDs with all the old emails to
be sure.
Some of the part dates are later as a computer crash
or two
happened with copies of the dwg's re-installed which
changes
the file dates.
Most constant speed props at the time and still do
today use
a forged two piece aluminum hub with separate two
piece steel ball
bearing races. This is done to capture the blades.
Blades need ball
bearings or you would never be able to change the
pitch due
to the tremendous centrifugal forces.
The idea (mine I think but I am not sure) was to use
a one piece
steel hub with internal grooves in it to feed in the
ball bearings in
one at a time. The outer race for the ball bearings
was integral
with the steel housing. This was an enormous
simplification of a
constant speed prop hub. Furthermore aluminum has
lousy
fatigue characteristics so I used tig welded 4130
steel. John Moran
built some of the early parts.
I was using ACAD 10 at the time so you will have to
excuse the
crude dwg's. Butch undertook the dwgs job as he was
using something
more sophisticated than ACAD DOS Version 10.
Improvements were suggested
by other people. Bill Freeman did the blade design
using spread
sheets. Perry Mick built the carbon fiber blades.
Butch had access
to a NC machine shop and did a fine job of building
the hub. Butch
also had access to an FEA program and an FEA and
high speed hub
testing was done.
Several years ago somebody from NC volunteered to
test the prop but
dropped the ball. That is the current status. We are
still trying
to get it tested.
Paul Lamar ...No rotor no motor.
guys
i would like to put the story straight. we talked to
butch two consecutive years at sun-n-fun about the
prop. he said no one had come though to test the prop.
so we offered.
we were building a lancair es with a 20b turbo. we
mounted the motor to a test stand with the prop on it.
we spooled it at about 1500 rpm. we were ready to test
the prop.
lou called butch to set a time for him to come down
for the test. he heard the motor running over the
phone. but like a lot of other times during this
process butch was called on another project for the
government. so he did not get to come down to s.c.
so we put the motor in the lancair and are trying
to finish our project.
no fault of ours or butch's but the project went
stagnet after that.
thanks for listening
paul brannon N117ES
Thanks for the update.
How's your Lancair ES coming Paul?
How far along are you?
BTW I think the LAEV prop is too small for a 20B.
With a good intake man you should get around 300 HP or more.
Paul Lamar
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