Props, Props and more Props

"Any thoughts would be appreciated regarding Whirlwind propellers"

Whirlwind will ship direct to Oz - at least they did for me a few years ago.

I have one on a 912ULS powered Sling 2, I'm not sure I'm all that happy with it after about 150 hours.

It looks great but I can't find a pitch setting I'm happy with. I've settled at the "least worst" pitch that gives me only 5100RPM on take-off but will still easily exceed 5500 RPM at any altitude up to 10,000' at WOT. I cruise at 5200-5300 RPM at about 50% throttle. It is safely within the RPM/MAP limitation listed in the manual so I could sneak a bit more pitch for cruise but then I lose even more RPM for take-off from my relatively high, 1900' elevation airport with lots of surrounding hills. I'm unable to utilise the full power of the engine at either end of the spectrum.

The bolts Whirlwind use/supply are nothing special either, they appear to be just commercial high tensile steel that are rusting.

Not Evektor specific but I hope this is of some interest to you.

Cheers.

A ground adjustable prop is just one step up from a fixed pitch, in that it can be "tweaked" within fairly tight limits, to suit the airframe and mission profile.

The performance you have described is pretty much all that can be expected - a compromise.

The makers of E-prop would suggest that their concept, of a ground adjustable prop, performs somehwat better than most - I don't know however they seem to be gaining quite the support base here in Australia.

Unfortunately with a factory built LSA in Oz (SLSA in the USA) we are restricted to installing only the manufactures "approved" equipment. Gregg mentioned the 2 props for the Evektor & Sling lists either the Whirlwind, Warp Drive or Sensenich 70-72" 3 blade props for the Sling LSA.

Des Howson wrote:

Unfortunately with a factory built LSA in Oz (SLSA in the USA) we are restricted to installing only the manufactures "approved" equipment. Gregg mentioned the 2 props for the Evektor & Sling lists either the Whirlwind, Warp Drive or Sensenich 70-72" 3 blade props for the Sling LSA.

Sometimes the factory can surprise you - try writing/email asking for a written dispensation. If they allow the change/modification make sure you keep the letter as evidence of factory permission (to satisfy RAA).

Alternative - register the aircraft as E (experimental) with RAA then you can make whatever changes you wish (stay safe). The only down side of E is you cant hire out your aircraft and if it remains as E (you haven't restored it to origional build) the sale value may be diminished a little.

Thanks Sean, I'm really not interested in changing my prop and I'm not with RAA, she's VH registered. I was only trying to give feedback as requested by Gregg. Cheers.