X-Mozilla-Keys:                                                                                 
June 1999
         
The past few months have been very busy at the Powersport hanger in
Osceola. We have spent a great deal of time engineering components,
solid modeling them, searching for qualified suppliers, and fine
tuning the product concept that we will deliver. We have acquired an
RV-6A for construction of our first firewall-forward product. In
addition to this we have been working the extra hours to try and make
Oshkosh with a representative sample of what we intend to provide our
potential customers. Morale is very positive because we have improved
the original design considerably, and added to the performance,
functions, and reliability of the original "Hatch" concept. I would
like to take the time to describe our vision of what the Powersport
firewall-forward concept will be.  

The original internal gear concept
is retained in the production Powersport concept, but we have
provided additional tooth width to strengthen the gear. This does
some very significant things for us. First of all we are now able to
insure that the set will be able to take the loads of the future
supercharged engines we are planning. Secondly, the reliability has
been dramatically improved. We will talk about this at the completion
stiffness has been improved to ensure that the natural frequency of
the system is high enough to avoid resonance in the operating range
of the engine. (Idle to 6000 revs.)

 When we improved the gear-set we also in fact changed the gear
housing that was used to mount the set. We took this opportunity to
increase the strength to weight ratio on this part, and were able to
incorporate an oil sump for the gear/bearing set.  This allows us to
run the optimum oil for the reduction gear, without being constrained
to the engine oil. It also allows us to run our own mechanical
lubrication pump within the housing. The gear oiling system will be
able to provide lubrication and pinion gear cooling at all attitudes.
We are using finite element modeling to check the housing for
distorsion under load to assure that our high precision gear set
maintains the appropriate alignment under the most severe loading
conditions. We are using the Solidworks program to model the entire
system.

Another phase of the program is to develop a redundant engine
management system.  Powersport is finishing the developemnt of a
custom designed Electronic Fuel Injection/Ignition system.  Dyno
testing of the new EFI unit will commence on July 12th, 1999.  This
system is specifically designed to offer double redundancy on all
critical sensor sites, and in the electrical system that powers it.

The system will be capable of operating for periods in excess of an
hour on the battery backup alone (alternator failure). The system
offers the rotary engine customer improved fuel economy, by
providing closed loop feedback to dual computers for appropriate in
flight fuel trimming. In effect, the computer modules are
continuously adjusting fuel flow to provide the best brake specific
fuel consumption available. 

The pilot will have single lever control
of the throttle for ease of operation. Of course the system will
adjust for temperature, barometric pressure (altitude), dirties air
filters, yengine temperature, system voltage, etc. The system will
also feature spark plug mounted coils. The advantage of these is that
they have a positive connection to the spark plug, and effectively
eliminate any external high-tension leads. This is better for wiring
harness durability and noise suppression. 

The really nice feature of
an extensively mapped engine like this is that the engine does'nt
care what propeller the customer bolts on.  The system will sense the
load line and adjust fuel and ignition timing automatically! Thus
allowing the customer to experiment with different pitches etc. In
the future the system will also control the wastegate on the
supercharger for increased power on takeoff. Perhaps this will make
the need for an expensive constant speed propeller less apparent.

 Speaking of propellers, we have made provisions in the design for
constant speed propellers. Initial testing will begin with a
propeller from Global Aircraft Corporation.  We have received the
first sample of their Quasi-Constant Speed (QCS) propeller.  This
concept seems to be a very good trade-off for us in the debate over
fixed-pitch simplicity and multi-mode efficiency. We plan to test
traditional constant speed units in the future. However, we will not
provide the F-flange until we have extensively tested the system for
damaging torsional resonance. This really is not unlike the rest of
the program. 

We have committed to providing a thoroughly engineered
engine alternative and will not take a dime from anyone until we are
sure that we have done our job responsibly, and correctly. We are
doing revolutionary things here at Powersport, but we do not wish to
risk our customers lives and our reputation.
Other developments include the mounting and packaging of the system
in an RV-6A airframe. 

We are developing focalized engine mounts to
isolate the engine vibration from the airframe. We are also working
to design a more aerodynamic cowl that better fits our engine
application. The system will also incorporate the cooling system,
electrical charging system, air intake/throttle system, and exhaust
system. In effect the Powersport customer will just have to bolt up
the cage / engine, plumb the fuel, wire the electrical power, and
start his pre-tested engine. 

We will keep you as a potential customer
informed of our progress, and ask for your patience. We intend to
begin shipping first samples on or before January of this year. We
are costing the package as we complete the installation, and will
update this information as well.

 Respectfully,
 Steve Weinzierl
 Engineering Manager-Powersport Aviation


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