![]() |
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. |
Bill, what was your TAS, level flight at 12,500? Mark C.
|
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. |
Mark, my WOT and leaned for best power (75%?) at 8,000' DA is 174 knots.
|
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. |
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? |
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.
|
Close
Mark, your numbers are close to mine. Bill's piece is quite a bit faster than mine.
|
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. |
Quote:
|
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. |
those are good numbers.
|
Quote:
|
Quote:
|
Quote:
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. |
Quote:
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. |
Quote:
|
Quote:
159 knots @ 5.2 GPH. Not bad at all! I love the -9 wing! |
Quote:
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. |
Thanks
Thanks for the data; great stuff
|
Quote:
Quote:
|
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.
|
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! |
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. |
Quote:
|
Quote:
|
Quote:
|
Quote:
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. |
Quote:
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) |
Quote:
|
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.
|
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. |
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..... |
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. |
Quote:
|
| All times are GMT -6. The time now is 08:39 AM. |