912-914

[Flybyjim]

A big thank you for the photos and info, I can't stop druling

[Av8r3400]

Having just gone through all the grief I did concerning my gearbox, I believe it was caused by exceeding the mass moment of inertia rating for my early model gearbox.

Has anyone ever done this test to the Airmaster prop to determine the long term effects of such a heavy (albeit very high performing) propeller system?

[War Eagle]

Having just gone through all the grief I did concerning my gearbox, I believe it was caused by exceeding the mass moment of inertia rating for my early model gearbox.

Has anyone ever done this test to the Airmaster prop to determine the long term effects of such a heavy (albeit very high performing) propeller system?

The answer to your question is yes. The test was not done by myself but by Airmaster.

The system I have is the AP332 with the WD blades. I'll try to tell you what I have been told in relationship to this line of questions.

The largest WD blades do exceed the stated limit from Rotax as they are heavy at the tips. As I understand, all other blade types are below the the limit of .6kgm2. As an example the tests show the AP332-WDT68R is .595kgm2 and the AP332-WDT72R is .68kgm2 and my setup comes in between those two at .6kgm2.

As I understand there have been no reported gearbox failures due to MOI issues on any installed Airmaster setup. There has been some discussion as to whether it reduces the life of the sprag clutch but there hasn't been anything presented that is conclusive (a couple of units in question). As I understand, more important issues related to the sprag clutch can be things like starting, balance of the carbs and use of the soft start.

Airmaster has communicated to me that they have not received any reported issues related to the MOI and they have over 900 units in use on Rotax engines.

Their recommendation to me has been to avoid wide cord blades at diameters over 68 inches. If you need a wide cord blade over 68 inches then they would suggest using lighter blades than the WD. You must also consider service life if you are considering lighter blades.

Airmaster reported their most popular model of the Airmaster system is the AP332-WDT72R. Airmaster has said this model is used extensively in Russia and South Africa on the L-42 and the Sling.

http://en.wikipedia.org/wiki/Chaika_L-4

http://airplanefactory.co.za/models/sling4

Of the 8 CS props we have used on the Kitfox planes we have nearly 3000 accumulated hours with the single highest approach 1000 hours and there have been zero gearbox related issues. Airmaster has so many of these units in service that if there was really a problem out there it would be hard to cover it up.

[War Eagle]

War Eagle,
Your plane is just hands down beautiful! And, thanks for taking your entire prop assembly off, cutting your spinner in half and mounting it all on a tripod so we could see it! Now put it all back together and go fly!

Do you think if I use Hysol I can put that thing back together again and make it good as new?

[Pingert]

As per props I have an airmaster prop on for 230 hrs no problems would not have any thing else have a 914 turbo kind of beefed up put out around 130hp plus manifold on boost to 39 inches to 8000 and 36inchs to 13000ft lift off always around 250ft at 2800 elevation and that's no BS
But my guestion is has any body having issues with hot starts after shutting down seems to vapor lock is there any little tricks to start!!!!!

[Av8r3400]

Do you have the return to tank line installed in your fuel system? (I don't know if that is an option on the 914.)

This does a lot to help solve vapor lock on the ULS motors.

[Pingert]

Thank you for reply yes have a return line from header tank back to right tank so what happens is the return from engine goes to header tank and excess back to right tank wonder if there's an other way .But one of the ways I manage it is to shut off fuel and cool turbo down for approx. 2min. but still hard starts some times.

[Paul Z]

War Eagles Veg-O-Matic It slices and dices.

That is one nice Airplane!

https://www.youtube.com/watch?v=1GniNeqSX5U