[Homie]

Who has a Whirlwind ground adjustable prop on their RV? I have a 9-a with 0320-160hp, thinking of going to the Whirlwind. Cato takes about 3 months from order to delivery (or longer), Whirlwind says about 3 weeks. Who can give me a comparison?

 

[RyanWhite]

I have a Sensinich ground adjustable on my 9A and love it.....

 

[Av8torTom]

Who has a Whirlwind ground adjustable prop on their RV? I have a 9-a with 0320-160hp, thinking of going to the Whirlwind. Cato takes about 3 months from order to delivery (or longer), Whirlwind says about 3 weeks. Who can give me a comparison?

I have a whirlwind - it's great

 

[PilotjohnS]

I have a Catto and love it….

See a pattern here?

 

[Av8torTom]

The advantage of the Sensenich ground adjustable prop is that it's easier to adjust than the Whirlwind.
The disadvantage of the Sensenich prop is that you're stuck with whatever set pitch changes they allow

The advantage of the Whirlwind ground adjustable prop is that it is infinitely adjustable
The disadvantage is that it's a bit trickier to adjust than the Sensenich.

At the end of the day I went with Whirlwind because it was significantly cheaper.

 

[riobison]

Any actual comparisons of before and after performance gains or losses?

 

[BH1166]

Who has a Whirlwind ground adjustable prop on their RV? I have a 9-a with 0320-160hp, thinking of going to the Whirlwind. Cato takes about 3 months from order to delivery (or longer), Whirlwind says about 3 weeks. Who can give me a comparison?

I do. Love it, pitched to my liking. Nice looking. Balanced well, nickel edge is in great shape. 380 hrs 3 years TT. Easy to mount and adjust. Took two tries to get what I wanted. One of my best upgrades to my O320 6A. I wanted better climb. I fly on top a lot in Summer. I need to get through openings….it does it. No increase in speed for me, no loss either, with better climb …. Im real happy!

 

[riobison]

I do. Love it, pitched to my liking. Nice looking. Balanced well, nickel edge is in great shape. 380 hrs 3 years TT. Easy to mount and adjust. Took two tries to get what I wanted. One of my best upgrades to my O320 6A. I wanted better climb. I fly on top a lot in Summer. I need to get through openings….it does it. No increase in speed for me, no loss either, with better climb …. Im real happy!

Numbers...................................

 

[BH1166]

2380 static, 2500rpm at 300AGL, 2700rpm 1500’AGL. Pitch allows 2780 rpm at my usual cruise altitudes , TAS goes up 156kts

Me= TAS almost always 150Kts , I run LOP 7.6gph

I believe that if looking for the prop to make more speed, then pitch accordingly, more climb pitch accordingly, having a marketing advantage over a fixed pitch high altitude buyer, pitch accordingly. 1096 empty weight, me 185lbs. 6A 1992 , old style wheel pants. Thats all I got. Whats your numbers Riobison today, prop today?

 

[maxmirot]

The advantage of the Sensenich ground adjustable prop is that it's easier to adjust than the Whirlwind.
The disadvantage of the Sensenich prop is that you're stuck with whatever set pitch changes they allow

The advantage of the Whirlwind ground adjustable prop is that it is infinitely adjustable
The disadvantage is that it's a bit trickier to adjust than the Sensenich.

At the end of the day I went with Whirlwind because it was significantly cheaper.

I have the WW. It might take a 10-15 minutes extra to change the angle on the WW.
It is not hard to do.
The Sensenich pin system looks attractive and would make adjustment simpler.
It depends on the resolution of the Sensenich. I would look for 0.5 degree changes.
That's what I needed to dial in my cruise RPM

 

[maxmirot]

2380 static, 2500rpm at 300AGL, 2700rpm 1500’AGL. Pitch allows 2780 rpm at my usual cruise altitudes , TAS goes up 156kts

Me= TAS almost always 150Kts , I run LOP 7.6gph

I believe that if looking for the prop to make more speed, then pitch accordingly, more climb pitch accordingly, having a marketing advantage over a fixed pitch high altitude buyer, pitch accordingly. 1096 empty weight, me 185lbs. 6A 1992 , old style wheel pants. Thats all I got. Whats your number Riobison today, prop today.

What is relationship between altitude and prop pitch setting ?

 

[blaplante]

I do. Love it, pitched to my liking. Nice looking. Balanced well, nickel edge is in great shape. 380 hrs 3 years TT. Easy to mount and adjust. Took two tries to get what I wanted. One of my best upgrades to my O320 6A. I wanted better climb. I fly on top a lot in Summer. I need to get through openings….it does it. No increase in speed for me, no loss either, with better climb …. Im real happy!

150 or 160 HP O320?

 

[BH1166]

150 or 160 HP O320?

o320/D1A. 160hp

 

[Scott Hersha]

The advantage of the Sensenich ground adjustable prop is that it's easier to adjust than the Whirlwind.
The disadvantage of the Sensenich prop is that you're stuck with whatever set pitch changes they

Not true, exactly…….. the pitch pin system allows 6 different pitch settings with the standard installation kit you get with the prop. You can order whatever different pitch pin you want from Sensenich, or you can just do it in a more accurate way using your magnetic smart level. Get the TOOL from Vans:

TOOL-00002

store.vansaircraft.com

Use your smart level with this inexpensive tool to set your blades where you want them - any GA prop, not just Sensenich. Understand how to use this tool and make sure your blades are within .1* or less of each other or you will feel vibration. The Sensenich pitch pin system might end up perfect, or maybe not quite. The last time I did mine just using the pins, I felt vibration I didn’t feel before, and when measuring with this tool, I was .3* off. When I matched them with the tool, the vibration went away. Then I did a DynaVibe prop balance using my chapter’s balancer and with 2 weights strategically placed I got the balance to 0.00 ips. It is definitely smooth. Whirlwind makes a good prop, so does Sensenich. Sensenich now has a three blade GA (maybe Whirlwind does too). I talked to the Sensi folks at SNF and got this about that. The 3 blade performs exactly the same as the 2 blade up to about 8,000’. Above that altitude, the 2 blade does slightly better. The difference is in the sound, smoothness (slightly favoring the 3 blade) and looks while parked on the ground - also favoring the 3 blade. Just depends on what you want and can afford. I love my Sensi 2 blade. If I would have had a choice between the 3 blade and the 2 blade two years ago, would I have chosen the 3 blade? Yeah, probably, because I can be a vane SOB, and I have a taildragger. If I had an A model - no question, get the 2 blade.

 

[PilotjohnS]

so for you folks with ground adjustable props, when you turn the pitch down to get higher RPMs at cruise, do you notice a reasonably higher airspeed, or is the speed the nearly the same, just at a higher rpm?

 

[jrs14855]

Whirlwind has a 2700 r/m limit with some modest over speed allowance. With my 0 320 Wittman Tailwind reducing the pitch would result in slower cruise based on my respecting the 2700 r/m.

 

[BH1166]

so for you folks with ground adjustable props, when you turn the pitch down to get higher RPMs at cruise, do you notice a reasonably higher airspeed, or is the speed the nearly the same, just at a higher rpm?

I have less pitch in mine for days like today. Takeoff at sea level, bottom of clouds 4000’, another layer bottom 6500’. Well myself and 2 others found a valley between clouds with a blue exit…go for it, on top at 8500’, not good enough, climb to 9000, 9500’……. In the south, you get beat up under the cumulus in spring to fall, so I need smooth air. Now, at cruise , I run 2600-2700, LOP 150kts TAS consistently. At each 25 RPM INCREASE over 2700, I pick up 1kt inTAS. I see a GA prop as one that can fit your need, the next owners need, and in winter in the south I can increase pitch, which reduces static RPM and climb, but now at cruise 156kts TAS at 2600-2700 RPM. I leave mine, not changed since getting it dialed in to my preference 39 months ago. I wasn’t sure what I wanted, other than better climb, but not a climb prop per se. I didn’t want to buy a new prop and not get what I wanted…GA, you are never stuck…change it. I can’t ever see not having a GA prop, unless wanting a CS prop. No names, but I keep up with CS 7’s, but issue for me is hot #1 #2 on climb, so I flatten and they pull away. Oh , me 160hp, them 180hp.
Today, 2700rpm at 1500’ climbing. Oh, I ve only bee up to 2780 rpm for brief time , 156TAS….YMMV

 

[Freemasm]

Whirlwind has a 2700 r/m limit with some modest over speed allowance. With my 0 320 Wittman Tailwind reducing the pitch would result in slower cruise based on my respecting the 2700 r/m.

Interesting. Could you share the related literature?

Basically every professional society of consequence states 10% OS must be allowable in their specs. That's about 20% greater related forces than nameplate. The divergence in specs is (was, been since I was involved in such) no inspection versus a visual only (no tear down). Let us know if you would please.

 

[BH1166]

Interesting. Could you share the related literature?

Basically every professional society of consequence states 10% OS must be allowable in their specs. That's about 20% greater related forces than nameplate. The divergence in specs is (was, been since I was involved in such) no inspection versus a visual only (no tear down). Let us know if you would please.

That's what their specs state

GA200L PROPELLER

whirlwindpropellers.com

 

[Dbro172]

the whirlwind is a great prop for the cost and availability. I’ve had a 2 blade catto, 2 blade GA Whirlwind and now a 3 blade Catto. It’s really tough to beat the performance of the 3 blade Catto; quieter, better climb and same or better top speed as the WW. A pain to remove the cowl with 3 blades however. I was down low this morning but pushed her up to 2700 RPM for a minute for 164KTAS. (O-320), not even full throttle.




Less Fuel higher up though

 

[Freemasm]

OK. That’s just a max rpm. Nothing special, unusual (for the application) or unexpected there. Is there’s an unusual requirement for xx% OS? From what I can see on my phone, there’s nothing of real consequence here, versus the market

 

[Homie]

Thanks for all the comments and input…. I have ultimately decided to go back with a Cato 3-blade with the nickel leading edges. I went with a 66Dx72P, this is their “best all round” prop. For my 160 hp they also have available a 71“P which is more of a climb prop and a 73”P which is the “cruise” prop. They do however point out that all 3 props are capable of the same top speed, just at different RPMs.

 

[PilotjohnS]

Thanks for all the comments and input…. I have ultimately decided to go back with a Cato 3-blade with the nickel leading edges. I went with a 66Dx72P, this is their “best all round” prop. For my 160 hp they also have available a 71“P which is more of a climb prop and a 73”P which is the “cruise” prop. They do however point out that all 3 props are capable of the same top speed, just at different RPMs.

I thought my 3 blade catto was pitched too coarse because I am only seeing 2500 at high altitude cruise at 144 kts. I thought I would get more speed by winding it up. But apparently all a higher RPM does is burn more fuel. . And my speed is off by about 1% too.

In the end I figure it doesnt matter if I am a few knots faster. As Vans said many times, one needs to think of these as tractors, not swiss watches.

It gets me where i want to go, really inexpensively (I'll save the "cheap" terminology for a description of me)

And the Catto is smooth.

As can been seen in the photo above, when the throttle is pulled back a little, the mileage per gallon really goes up, and the speed drops only slightly. Just a slight pull of the throttle up high and I can get to 23 NMPG