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-   -   How well does an RV-9 climb? (https://vansairforce.net/community/showthread.php?t=146784)

N941WR 02-17-2017 09:42 PM

How well does an RV-9 climb?
 
Pretty darn good!

After finishing work today, I had some flight testing to do, which required a climb from 1040' AGL to 12,500' AGL. Every 1,000' feet I leveled off to let the plane accelerate, throttled back, powered back up to full power, and then resumed the climb.

I just checked the data and it took 13:08 from brake release to level out at 12,500. My average climb rate was 871.3 FPM and my average speed was 122.4 knots. That's pretty impressive and makes me want to try a Vy climb from sea level to 12.5.

I was still putting out 18.7" MAP at that altitude. (The pressure altitude was 14,930.)

BTW, my plane as a stock ECI O-360 and a FP Catto two bladed cruise prop.

Mark C. 02-17-2017 10:07 PM

Bill, what was your TAS, level flight at 12,500? Mark C.

N941WR 02-17-2017 10:19 PM

Mark, I'm not really sure since I didn't do a speed run. Almost as soon as I hit 12.5, I throttled back and started down hill. (I was testing the EIC at different power settings, not the airplane.)

The data shows 162 knots but I wasn't leaning for best power. The SkyView was showing 58% power and 9.6 GPH.

N941WR 02-17-2017 10:24 PM

Mark, my WOT and leaned for best power (75%?) at 8,000' DA is 174 knots.

grubbat 02-18-2017 06:30 AM

Sounds fun
 
Time to climb to 12,000? Guess this needs to researched. ��
I could do it from say 900msl to 12,500. Best climb rate in the -9 would be around 105 TAS so no flaps.

N941WR 02-18-2017 07:21 AM

Craig, when you get out of Phase 1 we can meet at Brunswick and do it out of there.

Maybe Mark and Bruce will join us.

I wonder how we would stack up against a Rocket, if we continued to 17 5? Will our wing make up for the lack of power as the air density drops off?

Mark C. 02-18-2017 05:16 PM

Bill and Craig, on Friday I had a passenger both of us about 175lbs full fuel tanks. Power climb to 8,500 leveled off the best reading was showing 186mph off the Skyview slight leaning. Your 174 knots is 200.24mph. I have an IO360 with a Catto cruise tri-prop. I don't remember seeing 74% power. Mark C.

grubbat 02-18-2017 06:02 PM

Close
 
Mark, your numbers are close to mine. Bill's piece is quite a bit faster than mine.

tsneidin 02-19-2017 05:48 PM

My time to 12k results
 
I have a RV-9 with and IO-360 and 3 blade Catto. From take off elevation of 900 to 12,000 took 10:22, average VS 1083.

Level at 12k leaned for best power was 173kts at 8.6gph, MAP 19.2, 63% Pwr, DA 13360.

N941WR 02-19-2017 06:47 PM

Quote:

Originally Posted by tsneidin (Post 1151470)
I have a RV-9 with and IO-360 and 3 blade Catto. From take off elevation of 900 to 12,000 took 10:22, average VS 1083.

Level at 12k leaned for best power was 173kts at 8.6gph, MAP 19.2, 63% Pwr, DA 13360.

Todd, that sounds about right for a 360 powered -9. I really wonder what it would do if Craig cut a prop specifically for a time-to-climb run.

airguy 02-20-2017 08:04 AM

I did a climb to 17,500 yesterday to check out my oxygen system after working on the regulator (yes, with a fingertip blood sat checker), I didn't specifically watch the time-to-climb but I was up and back down again in 36 minutes. My home strip is 2700' and I climbed at 1000/min until 10,000', then climbed at 95 knots after that, I was still climbing at 500/min when the autopilot leveled at 17,500.

IO360, Whirlwind prop.

Steve Melton 02-21-2017 10:09 AM

those are good numbers.

PilotjohnS 02-21-2017 06:25 PM

Quote:

Originally Posted by Steve Melton (Post 1151935)
those are good numbers.

Steve, your configuration is going to be closer to mine. What do you plan for cruise and what climb rate and speed do you use for everyday missions. Lastly any high altitude speeds and fuel flow?

Steve Melton 02-22-2017 07:12 PM

Quote:

Originally Posted by PilotjohnS (Post 1152085)
Steve, your configuration is going to be closer to mine. What do you plan for cruise and what climb rate and speed do you use for everyday missions. Lastly any high altitude speeds and fuel flow?

I have become slower after painting or I'm loafing the engine more or maybe it's the dreaded paint weight. I plan at 140 kts cruise, normal climb =700 fpm. Fast climb on takeoff at 90kt >2000 fpm when OAT < 3C. On the last flight from Kansas to Cincy at 11.5K my TAS was 139 at 2200 RPM burning 5.7 gph, OAT =1C. On that flight I had a great tailwind (like 50 kts) and burned 21 gal for 600 nm.

N941WR 02-22-2017 07:24 PM

Quote:

Originally Posted by Steve Melton (Post 1152392)
I have become slower after painting or I'm loafing the engine more. I plan at 140 kts and normal climb =700 fpm. Fast climb on takeoff at 90kt >2000 fpm when OAT < 3C. On the last flight from Kansas to Cincy at 11.5K my TAS was 139 at 2200 RPM burning 5.7 gph, OAT =1C.

You must be down around 50% power for those speeds? Those numbers exactly match what I saw when I had the O-290 in my -9, only my RPM would be up on the 2600 RPM redline (fixed pitch prop). All that worked out to around 60 - 65% power for that little engine that could.

With the O-360 I typically cruise it at 50 to 55% power which works out to 150 to 155 knots and 7 GPH. Up in the teens, it can burn a much lower fuel numbers while keeping the speed up there.

Steve Melton 02-22-2017 07:32 PM

Quote:

Originally Posted by N941WR (Post 1152399)
You must be down around 50% power for those speeds? Those numbers exactly match what I saw when I had the O-290 in my -9, only my RPM would be up on the 2600 RPM redline (fixed pitch prop).

With the O-360 I typically cruise it at 50 to 55% power which works out to 150 to 155 knots and 7 GPH. Up in the teens, it can burn a much lower fuel numbers while keeping the speed up there.

11.5K my TAS was 139 at 2200 RPM burning 5.7 gph, OAT =1C

Calculated by my spreadsheet, to memory of MP =20 Hg = 54% power.

And... I don't drive as fast as I used to. Maybe there's a correlation.

airguy 02-23-2017 07:33 AM

Quote:

Originally Posted by N941WR (Post 1152399)
With the O-360 I typically cruise it at 50 to 55% power which works out to 150 to 155 knots and 7 GPH. Up in the teens, it can burn a much lower fuel numbers while keeping the speed up there.

I like to cruise high, in the midteens usually, and typically I will see the same TAS of 150-155 on fuel burn of 6.4-6.6.

N941WR 02-23-2017 08:28 AM

Quote:

Originally Posted by airguy (Post 1152492)
I like to cruise high, in the midteens usually, and typically I will see the same TAS of 150-155 on fuel burn of 6.4-6.6.

Some time back I posted this.

159 knots @ 5.2 GPH. Not bad at all! I love the -9 wing!

airguy 02-23-2017 09:44 AM

Quote:

Originally Posted by N941WR (Post 1152511)
Some time back I posted this.

159 knots @ 5.2 GPH. Not bad at all! I love the -9 wing!

Ok, you might win bragging rights on that one for now - but just let me get my injector orifices (orificii?) dialed in and we'll play a little... :D

In any case, I get asked all the time what kind of efficiency I get and I normally respond with "I flight plan 160 knots true at 8 gph." More than once I've been called a liar straight to my face. I just shrug my shoulders and smile, it's not my job to make believers out of the spam-canners.

PilotjohnS 02-23-2017 09:45 AM

Thanks
 
Thanks for the data; great stuff

N941WR 02-23-2017 10:13 AM

Quote:

Originally Posted by airguy (Post 1152539)
Ok, you might win bragging rights on that one for now - but just let me get my injector orifices (orificii?) dialed in and we'll play a little... :D

Only I'm carbureted.

Quote:

Originally Posted by airguy (Post 1152539)
In any case, I get asked all the time what kind of efficiency I get and I normally respond with "I flight plan 160 knots true at 8 gph." More than once I've been called a liar straight to my face. I just shrug my shoulders and smile, it's not my job to make believers out of the spam-canners.

I hear you! I love give give them rides and watching their mouths drop wide open!

MarkW 02-23-2017 10:18 AM

I have the little IO-320, not the larger 180hp like some of you but I cruise at 155 kts TAS and lean back to get that. My GPH varies with altitude. Most times my altitude is determined by whether I brought the O2, how far I am going and weather. My TAS does not change with altitude only GPH. I can and do go to 12k or so and regularly see 5.8-5.9gph at that altitude. I can stay around 8.5k and still be around 6.5 GPH and 155 TAS. As Bill says, I love this wing.

PilotjohnS 02-23-2017 10:23 AM

Wow
 
Mark,
This is what i was hoping for in selecting the 9: speed the same up high but lower fuel flow. Thanks for the data. This is great stuff.
Need to find what Catto prop you have!

N941WR 02-23-2017 10:47 AM

Greg & Mark,

You two bring up a good point, the -9 doesn't really need the (I)O-360 to be a good performer. It's beauty is in its ability to cruise efficiently, which is exactly what Van hand in mind when he designed it.

The reason for the O-360 in my -9 is that it was only $500 more expensive at the time and 20 lbs heavier.

airguy 02-23-2017 11:36 AM

Quote:

Originally Posted by N941WR (Post 1152565)
Greg & Mark,

You two bring up a good point, the -9 doesn't really need the (I)O-360 to be a good performer. It's beauty is in its ability to cruise efficiently, which is exactly what Van hand in mind when he designed it.

The reason for the O-360 in my -9 is that it was only $500 more expensive at the time and 20 lbs heavier.

Same here. I like to cruise high and wanted the extra climb performance, it was hard to say no to an additional 20 horsepower at the expense of 20 pounds. I knew I was going to have a constant-speed prop anyway so I chose the lighter carbon fiber Whirlwind prop and got some of those pounds back. I traded a lot of dollars for those pounds, but I got 'em back...

N941WR 02-23-2017 11:50 AM

Quote:

Originally Posted by airguy (Post 1152579)
Same here. I like to cruise high and wanted the extra climb performance, it was hard to say no to an additional 20 horsepower at the expense of 20 pounds. I knew I was going to have a constant-speed prop anyway so I chose the lighter carbon fiber Whirlwind prop and got some of those pounds back. I traded a lot of dollars for those pounds, but I got 'em back...

I was so panicked about the weight when I was building. With the O-290, I was at 990 lbs for my first flight. When I upgraded I stayed with the Catto prop to keep the balance where it should be. Now I'm dreaming of a CS prop and if I can talk my wife out of the cash, it will be a composite CS prop, no question about it!

airguy 02-23-2017 12:13 PM

Quote:

Originally Posted by N941WR (Post 1152582)
I was so panicked about the weight when I was building. With the O-290, I was at 990 lbs for my first flight. When I upgraded I stayed with the Catto prop to keep the balance where it should be. Now I'm dreaming of a CS prop and if I can talk my wife out of the cash, it will be a composite CS prop, no question about it!

You've got a pretty good prop now with those cruise numbers, no doubt. I'm guessing you are sacrificing a little bit on the low end for takeoff and climb, though I know Craig makes a fine prop.

N941WR 02-23-2017 12:28 PM

Quote:

Originally Posted by airguy (Post 1152597)
You've got a pretty good prop now with those cruise numbers, no doubt. I'm guessing you are sacrificing a little bit on the low end for takeoff and climb, though I know Craig makes a fine prop.

You are right, Craig does make a great prop and even though I can see 2000 FPM, when solo, there is nothing like the push you get when taking off in an RV with a CS prop!

I don't do enough formation flying to justify the CS Prop and when I do, I just have to remind lead not to chop the throttle.

The funny thing is what when I'm on someone's wing and they have to land they drop like a rock whereas I just keep gliding and gliding and gliding.

MarkW 02-23-2017 12:34 PM

Quote:

Originally Posted by PilotjohnS (Post 1152558)
Mark,
This is what i was hoping for in selecting the 9: speed the same up high but lower fuel flow. Thanks for the data. This is great stuff.
Need to find what Catto prop you have!

John,
I don't recall the exact prop but Craig is one of those guys you trust to make the right recommendation. I went with a three blade and nickel leading edges. Still looks new after 350 hours and some trips with heavy rain. My last trip to Texas through a front took one of the Catto stickers off the blade but the leading edges still look great.
I have the Catto, P-Mags and fuel injection and I have had a few people tell me it is the smoothest plane they have been in. (they weren't referring to my flying skills)

rightrudder 02-23-2017 03:41 PM

Quote:

Originally Posted by MarkW (Post 1152606)
John,
I don't recall the exact prop but Craig is one of those guys you trust to make the right recommendation. I went with a three blade and nickel leading edges. Still looks new after 350 hours and some trips with heavy rain. My last trip to Texas through a front took one of the Catto stickers off the blade but the leading edges still look great.
I have the Catto, P-Mags and fuel injection and I have had a few people tell me it is the smoothest plane they have been in. (they weren't referring to my flying skills)

Yeah, John, just call Catto, tell them what airframe and engine, and they will nail the prop selection. Mine's a 70x70 two-blade with the YIO-320-D1A, 160 hp, and it pretty much hits all the Van's book numbers.

grubbat 02-26-2017 03:19 PM

Time to climb 8500ft
 
Time to climb from full stop at 900 ft msl to 8500ft msl took 5 minutes and 19 seconds. Oil temp 180deg , CHT 410deg at top of climb. I0360 with hartzel CS prop. Airspeed varied between 105 mph IAS at takeoff to 110 mph TAS at top of climb.

N941WR 03-04-2017 08:33 PM

Today I did a straight out climb from my airport to 12.5.

I started counting on the one data row before my airplane lifted off and stopped counting the data after the first row after it broke 8500' (and later 12,500').

From 1083 to 8500' it took me 4 minutes 54 seconds to climb 7418 feet with an average ROC of 1513 FPM. As soon as I took off and cleared the trees, I set the IAS to 103 knots on the autopilot and let it fly. My highest CHT was 410*F, same as Craig.

Continuing on to 12,500 it took me a total of 8:21 which worked out to an average ROC of 1367 FPM.

Not too bad for a fixed pitch cruise prop.

The thing that got me started with this was testing the EIC and some different timing configurations. I dialed the standard P-mag A config Max Advance back one notch (-1.4) and my 8,000' DA all in cruise and leaned for best power was 175 knots. (The SkyView is set to fly slower than that so I had to hand fly it.) My hottest CHT was 379 at those power settings and since I never fly there, I'm pretty happy with what I saw today.

grubbat 03-04-2017 08:39 PM

Nice
 
Bill, with those performance numbers, you are right there if not better than my CS prop. As a matter of fact, you got me thinking about pulling that heavy CS stuff off and putting that Catto I got hanging on the wall on my -9.

Good grief. I thought I was done with all these changes.....��

N941WR 03-04-2017 08:57 PM

Craig, those numbers don't count the acceleration you feel with your CS prop.

I only started counting one data row before the plane lifted off. I should probably go look at the lat/long and figure out how long the roll was.

Steve Melton 03-04-2017 09:19 PM

Quote:

Originally Posted by N941WR (Post 1155109)
Today I did a straight out climb from my airport to 12.5.

I started counting on the one data row before my airplane lifted off and stopped counting the data after the first row after it broke 8500' (and later 12,500').

From 1083 to 8500' it took me 4 minutes 54 seconds to climb 7418 feet with an average ROC of 1513 FPM. As soon as I took off and cleared the trees, I set the IAS to 103 knots on the autopilot and let it fly. My highest CHT was 410*F, same as Craig.

Continuing on to 12,500 it took me a total of 8:21 which worked out to an average ROC of 1367 FPM.

No too bad for a fixed pitch cruise prop.

The thing that got me started with this was testing the EIC and some different timing configurations. I dialed the standard P-mag A config Max Advance back one notch (-1.4) and my 8,000' DA all in cruise and leaned for best power was 175 knots. (The SkyView is set to fly slower than that so I had to hand fly it.) My hottest CHT was 379 at those power settings and since I never fly there, I'm pretty happy with what I saw today.

those are crazy good numbers.


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