HACman Press Release
Green Sky Adventures, Inc. introduces HACman.
Manual In-cockpit Mixture Control Kit for Rotax 2-stroke
UL series engines.
HACman, above left is a single, panel mounted, manual
control for in-flight mixture management in Rotax and other 2 stroke engines.
The new mixture control was designed to use as a stand alone unit, or
in conjunction with our automatic High Altitude Compensating (HAC) system.
It functions on the same principal as our Automatic HAC which mixes and
controls veturi and float chamber pressure, but with HACman, mixed pressure
is determined by pilot input. In a manual system, it is paramount that
control input results are gradual, and anticipated without wild fluctuation.
The Green Sky manual control, works incrementally by conventional, precise,
vernier-type input that is counterclockwise to lean. The fine vernier movement
of our metering needle gives a motion rate of only .213 mm per half
In testing, some notable advantages over automatic systems were discovered
but the general benefit is an ability to richen or lean the mixture, at
will, during flight. In recent testing, at 10,000' Density Altitude, climb
rate was increased more than fifty percent by adjusting mixture for peak
power which was about 25 degrees richer than peak EGT. Other testing
was conducted to 14,600 ft Density Altitude. Range of adjustment is approximately
80 to 100 degrees F on EGT, which makes it possible to run in the "normal
operating range" at most any density altitude extreme without having to
rejet. HACman is a bolt-on installation for current production Bing 54
36mm caruburetors. Green Sky Adventures, Inc., can economically modify
previous production carburetor bodies to accept mixture control.
Preliminary work is underway to develop a similar system for the Bing
64 Constant Velocity Carburetors used on HKS and Rotax 912 series 4 strokes.
Prices start around $150 for the controller, lines, fittings, jets
and clamps. For more information Contact: Green Sky Adventures, Inc.
888 887-5625 www.greenskyadventures.com