Cruise or climp prop?

[hcccs]

I have a wooden prop 68x76 on my RV4 with a Lycoming O320-E3D, 150 hp. Would that be a cruise or climb prop?

 

[Jvon811]

I would guess that it more of a cruise prop.

For your reference, my 160hp RV-4 has a Bernie Warnke 68"x74" prop and gets about 2250 RPM Static.

 

[Tailwind/RVGuy]

I agree with Justin. Probably more of a cruise prop. I have a Sterba 68/74 prop on my Lycoming 0320 E2C 150 HP. I get about 2250-2300 RPM on takeoff roll and can exceed 2700 WOT. Keep in mind, different prop mfgs have different designs. Can't really compare. What matters is how your engine performs with that prop.

What kind of rpm do you get on the takeoff roll and WOT in cruise?

Keith

 

[hcccs]

I agree with Justin. Probably more of a cruise prop. I have a Sterba 68/74 prop on my Lycoming 0320 E2C 150 HP. I get about 2250-2300 RPM on takeoff roll and can exceed 2700 WOT. Keep in mind, different prop mfgs have different designs. Can't really compare. What matters is how your engine performs with that prop.

What kind of rpm do you get on the takeoff roll and WOT in cruise?

Keith

At beginning of takeoff roll 2300 rpm. In cruise I don't know yet.

 

[Taltruda]

My fixed pitch sensenich prop on my 180hp -4 will make 2150 rpm static, yet in flight just hits 2750 up high, and if left wide open down low would go to 2850.. I would think if you are making 2300+ static, then you would be more in the “climb” prop territory.

 

[Mel]

Be careful comparing wood props from different manufacturers. They are NOT "apples-to-apples".

 

[rvaitor87]

Cruise V climb

I have a cruise prop for my -3, O-320 E2D, which I ordered from Sterba. On the ground I get 2,300 rpm. Cruise never exceeds 2,650 rpm. Sound to me like you could have a cruise prop, but as Mel said, all props are not created the same. Do some testing in the air, airspeed Vs. rpm, that will give you a good idea of how your prop will perform.

 

[Sanch627]

Cruse or Climb

I have a Catto 68x77 that I’m putting on a O360 A1A 180 hp for my 4, Catto states it a in between cruse and climb for performance. But as Mel says wood ,metal ,glass, it’s not apples to apples.

Chris RV 4 1212R
Tech counselor chapter 32

 

[rvbuilder2002]

I have a Catto 68x77 that I’m putting on a O360 A1A 180 hp for my 4, Catto states it a in between cruse and climb for performance. But as Mel says wood ,metal ,glass, it’s not apples to apples.

Chris RV 4 1212R
Tech counselor chapter 32

Actually I think what Mel meant (and I agree) is that you can't compare pitch values from different manufacturers because they do not all measure the pitch value in the same way.
I.E., A 68X78 from one manufacturer might have a very different WOT static RPM and speed performance than the exact same diam. and pitch from another manufacturer.
This causes some people to change to a different pitch value when swapping to a different prop. brand and then still not being happy with their airplanes performance because they bought based on the pitch value alone.

It is always best to talk with the manufacturer of the prop you are considering, and tell them the specifics of what you are looking for. They will be able to tell you what diam and pitch of their prop that you should have to attain the performance you are looking for.

 

[hcccs]

My fixed pitch sensenich prop on my 180hp -4 will make 2150 rpm static, yet in flight just hits 2750 up high, and if left wide open down low would go to 2850.. I would think if you are making 2300+ static, then you would be more in the “climb” prop territory.

The prop is a Ted Hendrickson prop 68"x76". Does anyone have a prop for sale which is somewhere around 78" pitch?