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RV 9A performance options

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riobison

Well Known Member
I have a really nice and new to me 500 hr 9A with an 0320, 9.1 cr and one light speed ignition with 1 mag.

With this prop and the 2600 rpm limit I feel like I'm leaving some performance and a few kts on the table.

Mostly I fly between 10,000 to 15,000 feet over the rocks in Western Canada as well as high DA airports.

I'm wondering what most of you guys are running for props and what kind of performance your getting?

Myself at 8200' DA I can pull 164 Kts TAS at 2630 RPM.

The engine is strong and will pull more RPM then that except I start getting that vibration that its placarded on so I need to back off to 2600 and 161 kts.

At 15,020 DA Im 156 kts TAS at 2550 RPM at peak power. I was still going up at 600 fpm when I leveled off.

Climbing out of CYQF at a DA of 3000 ASL its somewhere around the 1300 fpm.

Maybe a csp is an option and would help on the climb but that is a big expense.

With all the options on composite props, ground adjustable I'm thinking that maybe there is still performance left on the table?

Just wondering what everyone else is running and getting for performance?


Thanks
Tim
 
Tim,

I'll be interested in the responses that you get to this query.

I too fly from a fairly high field (5050'), with the closest, lowest pass through the Rockies at 11,700', effectively requiring at least 13,500' for safe passage over the Continental Divide.

I have a Titan IO-340 fixed pitch with dual pmags mounted on my -9. It is still in project status, though, so no flight experience as of yet. I have a 2-blade Catto 68"x75" that I'll be installing. With this prop, the engine doesn't have to be limited to 2600 rpm. Personally, I'm more interested in seeing decent climb rates at high DA than outright speed. Downdrafts can be wicked around our section of the Rockies.

Cheers, Ken
 
Hey Ken

If I didn't have the O320 Id certainly be looking at the O340. The Catto has pretty good reviews but I haven't seen much on the 2 blade on the O320 for comparisons in the RV9.

Tim
 
riobison said:
I have a really nice and new to me 500 hr 9A with an 0320, 9.1 cr and one light speed ignition with 1 mag.

With this prop and the 2600 rpm limit I feel like I'm leaving some performance and a few kts on the table.

Mostly I fly between 10,000 to 15,000 feet over the rocks in Western Canada as well as high DA airports.

I'm wondering what most of you guys are running for props and what kind of performance your getting?

Myself at 8200' DA I can pull 164 Kts TAS at 2630 RPM.

The engine is strong and will pull more RPM then that except I start getting that vibration that its placarded on so I need to back off to 2600 and 161 kts.

At 15,020 DA Im 156 kts TAS at 2550 RPM at peak power. I was still going up at 600 fpm when I leveled off.

Climbing out of CYQF at a DA of 3000 ASL its somewhere around the 1300 fpm.

Maybe a csp is an option and would help on the climb but that is a big expense.

With all the options on composite props, ground adjustable I'm thinking that maybe there is still performance left on the table?

Just wondering what everyone else is running and getting for performance?


Thanks
Tim
Click to expand...

I have an O-320 D1A (8.5 cr I believe) running one slick and a Surefly at fixed timing with a Sensenich prop and the 2600rpm limit in my 9A. I see the same TAS as you see. I’m sure I can replace the prop to get a bit more out of my plane but I really do not want to run at 2700 rpm. A constant speed prop will get you more flexibility but more money and weight. A constant speed will make it much easier to slow down.
 
Steve Iacoviello said:
I have an O-320 D1A (8.5 cr I believe) running one slick and a Surefly at fixed timing with a Sensenich prop and the 2600rpm limit in my 9A. I see the same TAS as you see. I’m sure I can replace the prop to get a bit more out of my plane but I really do not want to run at 2700 rpm. A constant speed prop will get you more flexibility but more money and weight. A constant speed will make it much easier to slow down.
Click to expand...

At altitude over 8000 I'm substantially less than 75% power at 2700 rpm. They are built to run these RPMs. I certainly have never had a problem with it. Oil consumption is running 40+ hrs a qt and comp is all in the high 70s.

Tim
 
riobison said:
At altitude over 8000 I'm substantially less than 75% power at 2700 rpm. They are built to run these RPMs. I certainly have never had a problem with it. Oil consumption is running 40+ hrs a qt and comp is all in the high 70s.

Tim
Click to expand...

I agree, you can run at 2700 but I prefer not to (also limited by my prop of course). I generally cruise at 2500. My constant speed buddies typically cruise at 2400.
 
I have O-320 D2A 8.5-1
Catto 3 Blade 3BRV67x69NLE
My prop limit is 3200 Continuous
I have never even been close to that and dont imagine I could if I wanted too.
I have run over 2700 for short times but then get too cheap and throttle down to save some fuel.

I need to spend more time up high but most of my flights are less than 90 min so I usually stay between 5500 and 6500. I would like to find a few more knots but satisfied with the speed I get.

When I asked, this is the response I got from Catto:

We limit the prop at 3200 continuous. There are no RPM ranges that you need to avoid.

It is good to check the torque after the first 10 hours so maybe do that if you haven’t done so and then every 6 months with season change.

No TBO on the prop, the nickel will occasionally need to be reconditioned around 1200 hours or so.

We use a waterbase paint, just scuff the tips and reshoot.
 
riobison said:
Yes, the cruise numbers are close for sure. What prop were they using? My ROC isn't even close to what they show.
Click to expand...

In the upper left corner of the that performance webpage they state they used a Hartzell 2-blade constant speed prop.
 
My data point

I've got an O-320-D1A, Hartzell CS. One slick and one Lightspeed. I recently flew home from Lexington KY (about 2:40 flight time) and got fairly typical numbers for me: at 9000 feet (DA 11,100), WOT, I got 158 KTAS at 2400 RPM. I frequently will dial the RPMs back because the fuel savings seems well worth a few knots.

riobison said:
I have a really nice and new to me 500 hr 9A with an 0320, 9.1 cr and one light speed ignition with 1 mag.

With this prop and the 2600 rpm limit I feel like I'm leaving some performance and a few kts on the table.

Mostly I fly between 10,000 to 15,000 feet over the rocks in Western Canada as well as high DA airports.

I'm wondering what most of you guys are running for props and what kind of performance your getting?

Myself at 8200' DA I can pull 164 Kts TAS at 2630 RPM.

The engine is strong and will pull more RPM then that except I start getting that vibration that its placarded on so I need to back off to 2600 and 161 kts.

At 15,020 DA Im 156 kts TAS at 2550 RPM at peak power. I was still going up at 600 fpm when I leveled off.

Climbing out of CYQF at a DA of 3000 ASL its somewhere around the 1300 fpm.

Maybe a csp is an option and would help on the climb but that is a big expense.

With all the options on composite props, ground adjustable I'm thinking that maybe there is still performance left on the table?

Just wondering what everyone else is running and getting for performance?


Thanks
Tim
Click to expand...
 
riobison said:
I have a really nice and new to me 500 hr 9A with an 0320, 9.1 cr and one light speed ignition with 1 mag.

With this prop and the 2600 rpm limit I feel like I'm leaving some performance and a few kts on the table.

Mostly I fly between 10,000 to 15,000 feet over the rocks in Western Canada as well as high DA airports.

I'm wondering what most of you guys are running for props and what kind of performance your getting?

Myself at 8200' DA I can pull 164 Kts TAS at 2630 RPM.

The engine is strong and will pull more RPM then that except I start getting that vibration that its placarded on so I need to back off to 2600 and 161 kts.

At 15,020 DA Im 156 kts TAS at 2550 RPM at peak power. I was still going up at 600 fpm when I leveled off.

Climbing out of CYQF at a DA of 3000 ASL its somewhere around the 1300 fpm.

Maybe a csp is an option and would help on the climb but that is a big expense.

With all the options on composite props, ground adjustable I'm thinking that maybe there is still performance left on the table?

Just wondering what everyone else is running and getting for performance?


Thanks
Tim
Click to expand...

It is pretty unlikely that the vibration you feel is the one that the propeller was placarded at a 2600 RPM limit for. I suppose it’s possible, but that type of a vibration mode is not something you can typically feel in the air frame.

Another thing to keep in mind is the certification testing for the propeller was done with standard compression ratio, and standard ignition timing.

Running it on an engine with one or both of those details being different like it is on your engine, can move the critical vibration to a different rpm
 
A couple of weeks ago coming back from Stein's brat feed in my -9A IO-320D1A with MT composite CS prop, dual pmags, at 8500 feet at 75% power (2500/23"), just me and 26 gallons of fuel, 50° ROP, I was getting 167kts TAS.
 
rvbuilder2002 said:
It is pretty unlikely that the vibration you feel is the one that the propeller was placarded at a 2600 RPM limit for. I suppose it’s possible, but that type of a vibration mode is not something you can typically feel in the air frame.

Another thing to keep in mind is the certification testing for the propeller was done with standard compression ratio, and standard ignition timing.

Running it on an engine with one or both of those details being different like it is on your engine, can move the critical vibration to a different rpm
Click to expand...

Thanks Scott,

I had always wondered on the vibration being something that I could feel or not. I just changed the cyls due to the ECI AD and put the 9.1 cr in there so I don't know what was there before as i never flew it with the original compression ratio. But certainly its there at 2650, no doubt that I need to throttle back.

At 8000 ft it will pull past the 2650 if I let it but I don't.

Otherwise at 2600 rpm or idling @ 550 rpm its smoooooth.

Thanks
Tim
 
MacCool said:
A couple of weeks ago coming back from Stein's brat feed in my -9A IO-320D1A with MT composite CS prop, dual pmags, at 8500 feet at 75% power (2500/23"), just me and 26 gallons of fuel, 50° ROP, I was getting 167kts TAS.
Click to expand...

Sounds better then book specs. I'm sure your climb out at the lower elevations are as good or better than the Vans numbers.

Tim
 
Any more comparables with FP, ground adjustables etc on the RV9? Ideally with the O320.

Or comparables on the O340 or O360?

Thanks
Tim
 
9A performance

12500,
18 MAP
2520 RPM
66 ROP
79 Pitch Prop
2 P Mags
O320 DA1
157 TAS

Just another data point at a different altitude.
 
I’ve used the fixed pitch Sensenich carbon fiber ground adjustable prop on my last two RV’s - my former RV4, and my current RV6. Both airplanes had the O-360 standard 8.5 compression. Both ran smoothly all the way to 2700 RPM, which I set during flight test. I set the pitch to allow the Lycoming limit of 2700 at wide open throttle. I can get 2700 all the way to a relatively high (for Ohio) altitude of around 11,000’, although I don’t run it that way. Typically, 65% power at 9500’ works out to about 2560 RPM / 19.5” MP. I’m very happy with that prop, and it’s less expensive than the metal Sensenich if you are buying new.
 
Sounds like you are doing pretty good at 164 kts.
I always fly LOP while in cruise so I can not tell you numbers that match.
I have a Titan IO-320 with two Pmags Catto three blade.
I get 155 kts 8k LOP, 7.2 gph and about 2500 rpm.
I feel my prop is pitched perfect, as I can not get over 2600 rpm.
Seems like if you can overspeed at that altitude you are under pitched.
 
MarkW said:
Sounds like you are doing pretty good at 164 kts.
I always fly LOP while in cruise so I can not tell you numbers that match.
I have a Titan IO-320 with two Pmags Catto three blade.
I get 155 kts 8k LOP, 7.2 gph and about 2500 rpm.
I feel my prop is pitched perfect, as I can not get over 2600 rpm.
Seems like if you can overspeed at that altitude you are under pitched.
Click to expand...

Yes, over speed 2600 and a vibration at anything over 2630 rpm. Ill probably go with a ground adjustable that isn't RPM placarded.

The problem is which one?

Tim
 
My numbers -9A

8000’ Da, 57f OAT, 2700 rpm, 165 TAS, showing 23.2 map, one up, full fuel. Sensenich GA. Cpi2. I had more with leaning, so I’m maybe a smidge underpitched. I like it just the way it is. I usually cruise 142-145 TAS at 20.x map and 2350 ish rpm, burning 7-7.5 gph based on tank refill. Dynon says 60% plus or minus, but I’m LOP in that condition, so I think that’s high. I admit to not being very targeted, I set 2400 in ROP cruise and start pulling mixture and accept what I get LOP and smooth (enough). I plan cruise at 140kt and 8 gph.
 
rjcthree said:
8000’ Da, 57f OAT, 2700 rpm, 165 TAS, showing 23.2 map, one up, full fuel. Sensenich GA. Cpi2. I had more with leaning, so I’m maybe a smidge underpitched. I like it just the way it is. I usually cruise 142-145 TAS at 20.x map and 2350 ish rpm, burning 7-7.5 gph based on tank refill. Dynon says 60% plus or minus, but I’m LOP in that condition, so I think that’s high. I admit to not being very targeted, I set 2400 in ROP cruise and start pulling mixture and accept what I get LOP and smooth (enough). I plan cruise at 140kt and 8 gph.
Click to expand...

Hello Rick
How does it get off the runway and what kind of ROC etc are you seeing?

thanks
Tim
 
I have a I0-360 CS 3 blade but sorry, I'd like to help you out but I'm too busy workin' on it fixin' things that are no go for me to give you the scoop. Seems the previous owners didn't do much nor know much about anything....LOL!

Last week I flew it from TN to MI at 8k, 155 kts TAS 2350, 24". Now it's down for needed repairs but when I finally get to flying it more, I'll certainly share.
 
Finally got to fly my -9a to actually go somewhere yesterday, after the prop and panel swap. Been fighting squalks for the last couple months. Flew my son from central Va to Philly to pick up a truck he bought. A beautiful day and very smooth flight at 4500 to minimize headwinds. 150+TAS at 7.3gph, 25mp and 2300rpm. IO-320, slick mag L, lightspeed R. Love this plane!
 

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Put on a CS prop

I ran 3 different props on my IO-320 powered -9A before i sold it. Sensenich metal FP, Whirlwind GA, then a WW151. Changing to the CS prop it was like a different plane. Performance in all phases of flight were improved. Really loved that plane. Only downside would be that engine out glide suffered. The CS prop was the single most significant performance enhancer!
 
In my experience the Sensenich metal prop is the best compromise prop for an O-320, but it does have to be pitched properly. Pitch changes are possible but expensive. A Sensenich or Whirlwind ground adjustable prop will give you the ability to tune for take-off or cruise performance.

Agree that a CS prop will be the no compromise option but is expensive and heavy.

You may be leaving a few knots "on the table" but what are you prepared to pay in $$$ and/or take-off performance to realize that speed?
 
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