Light Aircraft Association

I am interested in knowing if anyone has experience or knowledge of either mechanical or electric variable pitch props for the C-90 or O-200 engine?

I have spent the past few days scouring the internet for information and have come up with very little.

Thanks in advance

Phil

I saw a Jodel D.150 Mascaret a few years back with an electric 3 blader.. G-BIDG. Looked fantastic.

That D150 has a Potez engine though. The owner, Dave Gray, had an MT made for it and had to have vibration test etc carried out by the factory to make sure it was OK. I think he considered it a worthwhile modification.
Some Jodels (with O-200s) had Rattier ground adjustables, with metal blades but they are very rare now. Sensenich make a ground adjustable for the O-200, a version of their popular Rotax 912 prop but I don't know of any being used in the UK. I do know of a composite ground adjustable on a 65hp Continental (Luscombe) that performs surprisingly well. In flight adjustable or CS I can't ever recall seeing, which is rather surprising really.

It looks like the Hoffman mechanical prop fitted to the Grob 109 has an FAA approval for the O-200, but the downside is that it seems to have a 200 hour TBO which is very low.

Most on the new composite props electric don't seem suitable for direct drive engines due to power pulse problems.

The Prince P-TIP prop, which is fixed pitch, claims to deform in flight to give up to 4 inches of pitch change in the cruise, has anybody seen this for real?

Phil

I have seen Arplast props on O200’s in France – might be worth giving them a call. No UK distributer any more but the factory is very helpful (France).

Rod1

In theory a SR3000 in either 2 or 3 blade could be used as these have a wooden core like a MT prop. The mount for the brush holder would have to be made but as these work well on a Jab 3300 there is no reason really it should not work on a O-200 . Would have to check the prop flange PCD first.

Cheers

Thanks Kevin,

I didn't get any response from the factory to my enquiry so your input is very helpful. What is PCD?

Phil

PCD

Prescribed Circle Diameter

The diameter of the circle prescribed by the centre of the prop bolts.

Ian

The small Continentals have an SAE 1 prop flange - 5.5 in O/D, 4.375 PCD (Pitch Circle Diameter), with 6 off 0.375 dia bolt fixings, usually to drive lugs that are 0.625 dia and protrude 17/32 from the front face of the flange.
A central boss 2.25 in dia also protrudes from the front face, by 1 in.

Pendantic but...

P.C.D. = Pitch Circle Diameter.

mike hallam

I do not know if they are actually available but the old Aeromatic props might be a though - they are the only one I can think of which was approved.

From memory there was someone in the US who owns the rights and was going to start manufacturing. Worth googling......

Thanks chaps,

I looked at the Aeromatic props, but they are really expensive at nearly $5,500 plus VAT, shipping etc. The other problem is that they are quite heavy too.

The SR3000 option sounds promising, but the factory didn't respond to my enquiry, perhaps I will try them again.

Phil

PM sent to Pipster

ThePipster wrote:The Prince P-TIP prop, which is fixed pitch, claims to deform in flight to give up to 4 inches of pitch change in the cruise, has anybody seen this for real?

The Warnke prop fitted to my RV is supposed to do that. 'Almost Constant Speed' is the promise!

Can't really vouch for it either way as I've nothing to compare it with on the aircraft, but she does go quite well with it.