HISTORY AND DEVELOPMENT OF THE AEROTEK 2000 PROPELLER SYSTEM

 
Initial design and testing was started in 1992 and the first 3 bladed propeller was installed on a Lancair 0-235 fitted with a Lycoming 0-235 engine.After testing different blades including warpdrive blades we settled for our own blade design.

Extensive blade retention testing was carried out to the point where retention safety factor is five times the actual centrifugal load.

Different controllers were tested and we found it helpful to have automatic control but not essential because the propeller pitch control system always locks in the last actuated position.
The next Lancair propeller was installed on a Lancair 0-320. Extensive vibration analysis was carried out. Using Chadwick recording equipment we established a vibration mode at 2350 rpm (this is typical Lycoming 0-320) and programmed the controller to stay outside this rpm setting.

This type of propeller was manufactured and marketed as the Airmaster propeller, and subsequently installed on a large range of aircraft, mainly Rotax powered installations.
In May 2000 we sold the company manufacturing the Airmaster brand propellers but retained the right to develop new products.

Our new propeller design is based on extensive experience obtained in static testing, manufacturing, installation and flight testing of variable pitch propellers.

The new design is intended for the general aviation market and for this purpose we are operating a Cessna 152.

For the experimental aircraft where no type certification is required we still follow the same testing procedures and following static testing all first of type installations are flight tested and a vibration survey is carried out.

For vibration analysis we use Chadwick recording equipment and recording a vibration scan at different speeds and rpm settings a total picture is obtained of vibration levels and mode, where you can actually read propeller crankshaft, camshaft, oil pump, even cowling installation. If at any point the vibration level is above .2 IPS which is the lowest acceptable standard we can analyse which is the contributing factor and either stay out of this vibration range or redesign.

Over the years we have been testing different blades on the market and currently we are testing a new brand of composite blades, which are currently flown on a pusher installation and on a Jabiru 3300. Another two propellers are ready for installation on a Lancair 0-320 and a Cessna 152.