Has anybody checked actual roll rate in their RV?

[N355DW]

One of the cool things about in flight videos is that you can actually check the manufacturer's published roll rate against the timeline in the video editor. Here is a short clip of my 13 yr old niece in my old Extra 300L. The first roll is about 200 degrees/second, the second is about 230. I'm being gentle as it was her first aerobatic ride!

Actually, she did great. For those interested the trick is to pull the nose up a little and let it drop during the roll, that way we kept positive G through the roll, instead of a competition style where you would come out of your seat when passing inverted. A speedy barrel roll, if you will.

Anyway, at full stick deflection in level flight, WOT (about 155-160k) the best I could get in the Extra was 270 degrees/second. It would take at least two rolls to get to that speed.

Has anybody checked this in their RV yet? I'm not trying to compare the two planes, just curious if folks have done this and what the results might be.

http://youtu.be/rT9vnmVuCiY

[Jim P]

I've found about 90 -100 deg/sec for an RV-7, depending on airspeeed and technique.

[Ironflight]

I've been workign up to it in the -3....but haven't gone full deflection yet. It's not going to surpass a dedicated Acro machine, but it's noticeably quick.

Paul

[RWoodard]

Funny that you mentioned this...

Here's my first attempt in the Midget Mustang. The camera is mounted under the right wing, so there's a bit of dihedral that makes it look like I start and stop at something other than wings level.

http://www.youtube.com/watch?v=mUv8vF8ICcY

Heck, I'm no good, but it sure is fun messing around!

[kevinh]

Originally Posted by RWoodard

Heck, I'm no good, but it sure is fun messing around!

Cool - btw, in your youtube comments you say you aren't sure if the pulsing is due to the mount or electronic. In my case it was the mount. I solved that problem by making a slightly aerodynamic mount that was aft of the camera and kept it from moving in the wind.

[sandifer]

Originally Posted by RWoodard

Funny that you mentioned this...

Here's my first attempt in the Midget Mustang. The camera is mounted under the right wing, so there's a bit of dihedral that makes it look like I start and stop at something other than wings level.

http://www.youtube.com/watch?v=mUv8vF8ICcY

Heck, I'm no good, but it sure is fun messing around!

I don't have experience with the MM, but I've always wondered how the heck Mustang Aero came up with a 300 deg./sec roll rate in the listed specs. Your fastest one was about 130 deg/sec, which is still pretty good. With gap seal tape, my (Friese aileron) Pitts S-1S rolls about 180 deg./sec. It'll snap roll about 360 deg/sec if you hit one clean. Maybe they mean (snap) roll speed for the Midget.

[N355DW]

I think all manufacturers tend to exaggerate this a bit. I think Extra claims better than 300 degrees/ second. Maybe at Vne.

The fastest rolling plane I ever flew was Richard Giles first G-200. Full span ailerons and short, light wings. I have no idea how fast, but I bet it was close to 400/second. I remember I did about six consecutive rolls in it, and when I stopped my head smacked the canopy and my eyes did one more roll on their own! Wonder if that plane is still flying. Nice little machine, much better than the 202, until Chris turned it into the MX2.

To bring this back to RV's, I am thinking of making an extra set of flat wing tips with a slight fence in the rear, as Bill who posts as Willyeyeball here has done on his. Swap them out for contests. But I'm really not all that concerned, I think the RV's can out roll a Decathlon and do just fine in contests if they are flown smoothly. I like they way they look flying, I'm going to have to see if I can get a ride in one soon!

[WillyEyeBall]

Damon,
As you illuded, method of measuring the roll rate is a factor, especially since it's really an acceleration and deacceleration (start/stop) maneuver. When I went to the flat wing tips, I just wanted a relative repeatable method to compare the flat versus stock wing tips. Mounting the video camera forward, I set the entrance speed as 135 knots, pitched up slightly, neutralized the controls for 1 second, and full stick right or left. I repeated the rolls about 10 times right and left, with standard and without the flat wing tips. I don't have the nice movie making software with a 10th or 100th of a second timer/clock, so just viewed the video with a stop watch, timing from start to wings level for 1 turn. Repeated the measurements from the videos multiple times. Stock wing tips was 140 degrees/second. The flat wing tips rate was 160 degrees/second. Also the Dynon 10A would lock up with the flat wing tips, and I think that occurs over 180 degrees/second. Next time I'm out, I'll pay more attention to the exact pitch up angle if we want to compare aircraft using the same method. Surely someone in the Sebring area will give you an RV ride.
Bill McLean
RV-4 Slider

[RWoodard]

@ Damon Wack:

If you've flown a G-200, you're in a very luck group, indeed. I've got a buddy who was an OEM airframe parts supplier to Giles before the business went away. My buddy had enough left over parts that he built one for himself. I think there are fewer than 20 G-200's flying in the country. Two of them currently share the same hangar at KFNL. Another is based at nearby Longmont, CO.

Very cool airplanes. And you're right, they roll faster than anything I've ever seen. Here's a pic of the nicest G-200 you'll ever see ANYWHERE! If you look closely, the second G200 is in the background.

Oh. And BTW, I was going about 20 mph slower than I could have been in my Midget Mustang for those rolls. I hadn't been upside down in a couple of years so I figured I'd start slow!

[RonRV8]

Based on review of video where I have done consecutive aileron rolls, and timing from inverted to inverted to eliminate acceleration and deceleration, I consistently measured 3.0 seconds for 360 degrees, or 120 degrees per second. This was done in an RV-8 with an entry speed of about 150 Kt IAS.