J 2/400 prop selection

[jetjr]

Im researching a new prop - again

 

Im mainly looking for cruise speed, J200/400 mostly fly well below 600kgs,

 

Im leaning towards 2 blade sensinich - glass coated, 60 x ??

 

Opinions on 2 vs 3 blades, and experiences?

 

Is the Bundy made composite still around?

 

JR

 

 

[jetjr]

Yeah, I looked at that, couldnt get a good answer on its testing and success, seems there were some problems early on but may be OK now. Site says not yet approved?

 

Whos got one on a 6 cyl?

 

 

[facthunter]

2 or 3 blades.

 

You would only go 3 blades if you had a ground clearance or tip speed problem, wouldn't you?. Wood is safe® with Jabs. Sensenich have a good name and may not be any dearer than other possibilities. Nev

 

 

[jetjr]

Some reckon 3 blades is much smoother, and imporoves climb performance???

 

 

[facthunter]

Efficiency.

 

More blades doesnt give those things automatically as far as anything that I have read, indicates. You have to compare apples with apples. Props vary in so many ways. Big engines need more blades to absorb the Horsepower. High altitude needs wider blades, etc.

 

2- blade is easier to construct in a basic prop. Wood is safer and suits 2 blade. If you want ground adjustable, then composite is probably the go, and it wouldn't matter whether it was 2 or 3 blade, structurally, (just a matter of designing the hub.). Pushers and nosewheels tend to want to keep the prop. dia to a minimum, for obvious reasons, so might tend to go to more blades in that situation.. Nev.

 

 

[Relfy]

I've flown a J230 with a sensenich and it is an awesome combination. Easily achieved 120kn at 2800rpm. The only thing to be careful with running them is the back/rear of the blade is fairly thin and a few have cracked as the result of stone strikes on rough strips. I believe they aren't recommended for running off unsealed strips all the time.

 

 

[Vev]

Attached below is a a part qoute from from the press realese re Rod Stiff being awarded the August Raspet Momorial Award at Oshkosh last month.

 

Not sure if anyone in the forum knows the details, but clearly Jabiru are building a range of new props?

 

If you are considering a new prop, it might be worth your while to contact Jabiru and find out about these new developments?

 

"The Jabiru product range includes Jabiru factory manufactured aircraft, experimental kits, and aircraft engines. A range of propellers, designed to complement Jabiru engines, is being developed." (Rod Stiff)

 

 

Cheers

 

Jack