The all new car
was called the ?Corvair?. Between 1960 and 1969 GM
manufactured and sold 1.7 million Corvair cars. Approx. 2
million engines were built.
Advantages of the Corvair
The engine design
was of an air cooled, six cylinder. Several variations of
the engine produced between 90 to 110hp were offered. A
turbo charged version capable of producing up to 180hp was
offered as well. The Corvair engine with its light weight
was capable of producing a very high Torque of 190 foot
pound at a relatively low 3000 RPM range. GM boosted it to
180hp with the Turbo version. The Corvair engine,
structurally speaking, could be running all day long without
over stressing itself, providing you with the 110hp.
Corvair Engines Aircraft
air cooled, high torque and light weigh providing 100hp.
Need we say more?
It did not take
long for the hard core avid experimental and light sport
aircraft builders of the time to take notice of the small
size engine, producing just the right amount of power. In
1960, Bernie Pietenpol purchased a Corvair engine from a
Chevrolet dealer and installed it in his J-3 Cub. That was
followed by many Corvair installations on his Air Campers.
another avid experimental aviator followed suit and
developed his ?Chevy Bird? powered with a Corvair engine.
Waldo experimented with many Corvair powered airframe
These two great
aviators led the way to many other experimental and light
sport aircraft builders, all looking for a practical and
economical solution to power their birds.
Corvair Engine Issues and
the AeroMax Solution
As more builders
started to install Corvair engines on their planes and
accumulate flying hours, it became apparent that the engine
required more refinement. Flying a Corvair engine in an
airplane as opposed to driving one in a car, presents
serious issues that needed to be addressed for the sake of
?Safety in Flight?.
Issues: A propeller mounted on the
Corvair Crank shaft, turning at 3000 RPM will introduce
Gyroscopic and Asymmetric loads that will produce bending
loads that are many times larger than the twisting loads due
to the application of work.
In a car
application, the crank sees only the twisting load. Even
with a perfectly balanced and symmetric propeller, typical
flying maneuvers apply huge asymmetric loads on the crank.
The lateral bending forces on the crank, generated by the
propeller lead to crank failure.
Solution to the problem was to
nitrate the crank. A process resulting in a much stronger
crank. Bill Clapp of Aeromax Aviation had broken the crank
in his 100hp Corvair converted engine after 120 hours of
flight. Bill had the crank nitrated, and so far has
accumulated an additional 500 hours on his airplane without
Crank for the 100hp, 2700cc Corvair engine will provide you
with a high safety margin.
Additional issues: The thrust
we?ve experienced in the experimental aircraft market had
prompted several enthusiast builders to offer what is
referred to as a ?conversion kit? or several specific parts
to assist you with your Corvair engine conversion.
Other issues with
converting a Corvair engine proved to be stemming from
insufficiently designed and poor quality of some of the
components used or sold to builders. We have seen technical,
product and operational issues that required solutions for
safely using the Corvair engine in an aircraft application.
As an example, cracked starter rings, poorly built
distributors, poorly built engines and improper engine
installation or operation have been too common.
By far, the
majority of engine problems have happened because of:
Lack of an information manual for proper installation,
inspection, and operation procedures.
A common mistake
most builders make, is not calculating the cost of
everything that must go into their engine to end up with a
high quality and reliable aircraft engine. When I was
introduced to the Corvair phenomena I was told that one can
build a Corvair engine for as low as $3500. Let me assure
you of one fact: Unless you are a highly skilled builder /
machinist, have access to a machine shop and fabricate all
of the conversion kit components yourself:
You will not be
able to build a high quality Corvair engine for less than $
7,500. Don?t forget ? You?ll be spending an average of one
year chasing parts and services. How much is that worth?