Part 2 of my RV-7A Aerobatics Lesson

[TheHDPilot]

Originally Posted by sandifer

Another nice video Gene. Just curious - what was behind the recommendation to use right rudder in the initial pull into the loops? Unless your airplane has yaw trim issues, there's no reason to apply right rudder. If it was meant to correct the dragged left wing on the way up, that's best fixed by correcting your pull such that you pull straight back without inadvertently applying aileron.

Regarding that spin recovery technique, I assume he had you keeping the stick back so that you would not unintentionally bring the stick forward before you applied opposite recovery rudder, which could accelerate the spin. Your airplane seems to recover OK with rudder only, but not all airplanes are happy to do that. Standard (and more efficient) spin recovery would be to first apply opposite rudder and then immediately follow with moving the stick forward to around neutral. Good things to discuss on the ground with your instructor so you understand the reasons for the techniques you're using in the air.

Eric,
I see MarkW already replied with same thing i was going to say, P-Factor. If i don't feed in a little right rudder the left wing lags the right wing on the way up. I just assumed that it was the same principle as when climbing out on a take-off. No?

Spin / Stick Back... Yes, I guess I was letting the stick come (too far) forward before completely stopping the spin with the rudder. I realize that is the right way for me to be doing it, but i guess i was so hot and tired by that point and had lost my focus.

That brings me to a question on spins that i've had in the back of my head. For an Intentional spin, the stick is already all the way back because that's the way you force the spin to happen. But what about an UN-Intentional spin, say at the top of a loop or trying to do an Immelman? There, the stick probably won't be all the way back when the spin occurs (i'm guessing). So is the right technique to immediately bring the stick fully back until you stop any rotation that might be occurring by using the rudder, and then let the stick come forward to break the stall?

Gene

[TheHDPilot]

Originally Posted by sandifer

I notice lots of folks pulling large amounts of power off (even to idle) on the backside of loops for fear of overspeeding and blowing out low. This is not necessary, and will not lead to nice looking loops. As long as you exit the loop at just about the same altitude as you entered, it's physically impossible to gain airspeed during the loop if your power setting is constant. Don't pull power, just manage your G so that you end up about the same altitude as you entered. Of course, be ready to pull power if you mess it up a little.

Thanks for the explanation on this Eric! I don't know where I'd picked up on the idea of pulling power out on the down side, but you can even hear my instructor telling me to leave it in (when I asked why the AOA was chirping). It's reassuring to hear you confirming that he's correct.

Gene

[sandifer]

Originally Posted by TheHDPilot

I see MarkW already replied with same thing i was going to say, P-Factor. If i don't feed in a little right rudder the left wing lags the right wing on the way up. I just assumed that it was the same principle as when climbing out on a take-off. No?

Gene, the effect exists, but is much less pronounced at the high airspeeds of a loop entry compared to a Vx or Vy climbout. But there are lots of variables, which is why I'm not saying there is only one technique needed. Airspeed entries vary, pitch rates (gyro precession) vary, prop/HP combinations vary, etc. But for most people, these dragged wing conditions are caused by improper stick movement rather than rudder movement. First make sure you're pulling the stick perfectly straight back. And then if rudder is needed, use whatever it takes.

Originally Posted by TheHDPilot

That brings me to a question on spins that i've had in the back of my head. For an Intentional spin, the stick is already all the way back because that's the way you force the spin to happen. But what about an UN-Intentional spin, say at the top of a loop or trying to do an Immelman? There, the stick probably won't be all the way back when the spin occurs (i'm guessing). So is the right technique to immediately bring the stick fully back until you stop any rotation that might be occurring by using the rudder, and then let the stick come forward to break the stall?

It's hard to spin most airplanes unless the elevator AND rudder are nearly fully deflected...and held. You just don't do that while doing loops and rolls. That's not to say you can't snap out of figures, but a spin will generally only develop if you maintain near full deflection of both controls. The example of stalling on top of a loop will just lead to slight pitch and roll bobbles if you're coordinated, and a dropped wing if you're not. Try it next time you fly with Adam - try pulling the stick all the way back on top and see what happens. The airplane will protest, but you're not likely to actually spin.

Similar deal on top of an Immelman - if you get too slow and mishandle the elevator and rudder a little, you can snap out of the top. This is not uncommon. But this is really a stall/snap rather than a spin entry. Neutralizing the controls will immediately bring the aircraft back under control. It's very hard to get into trouble in any aerobatic airplane if you neutralize the rudder and elevator as soon as the airplane snaps, departs, stalls, etc. You don't need to go into spin recovery mode until you actually see a spin developing. You'll learn the difference between spin entries and simply snapping or stalling out of maneuvers. All pilots learning acro should gain experience with this.

[TheHDPilot]

Originally Posted by sandifer

Gene, the effect exists, but is much less pronounced at the high airspeeds of a loop entry compared to a Vx or Vy climbout .... First make sure you're pulling the stick perfectly straight back. And then if rudder is needed, use whatever it takes.

It's hard to spin most airplanes unless the elevator AND rudder are nearly fully deflected...and held. You just don't do that while doing loops and rolls ....
Try it next time you fly with Adam - try pulling the stick all the way back on top and see what happens. The airplane will protest, but you're not likely to actually spin. Similar deal on top of an Immelman...

Good points that I will try Eric. 1st, i will make sure the stick comes Straight back. I can easily imagine that i'm not being accurate enough there. 2nd, i will ask Adam if we can try hauling the stick back at the top of a loop. It's best i see what can happen under controlled conditions.

One follow-up question... Remember that guy who was very concerned that other RV guys would try to do Immelmans after watching me do them and end up in spins? Given your description of what would happen (most likely falling off rather than ImmelSpinning), can you explain what his concerns might have been?

Gene

[erikpmort]

You were really hard on yourself ! Of course the instructor is there to help you improve but don't feel so intimidated. You must have 180 hp cause you pull through the verticals much better than I do. But I'm learning from these videos that you are pulling a lot more than me. I keep my loops to around 2.5 gs which for my power isn't enough pull I think. Great video. I wish I could get instruction in my 6a and be in the aerobatic category.

[sandifer]

Originally Posted by TheHDPilot

One follow-up question... Remember that guy who was very concerned that other RV guys would try to do Immelmans after watching me do them and end up in spins? Given your description of what would happen (most likely falling off rather than ImmelSpinning), can you explain what his concerns might have been?

Gene, I had to go back and look, but he didn't explain his position in much detail and didn't respond to further discussion. The Immelman happens to be a maneuver that ends with low airspeed. If you mishandle the maneuver, you can snap out on top. Snapping is more likely than spinning with this one. I don't think it's too important to worry about whether it's a stall w/ wing drop, snap, or spin as you depart controlled flight. None of it is a big deal. Pilots flying solo aerobatics should be able to recover any type of loss of control.

[MarkW]

Thanks Eric,
I will pay more attention to rudder input during loops.

Just a note on the throttle during the backside of the loop.
My biggest fear of performing a loop in the RV was an overspeed on the backside. I feared that to control the speed I would need to pull excessive G's or allow an Vne.
Now I fly the loop with full throttle all the way around to keep my speed up/the same. Fears were baseless.
Thanks.

[TheHDPilot]

Originally Posted by erikpmort

You were really hard on yourself ! Of course the instructor is there to help you improve but don't feel so intimidated. You must have 180 hp cause you pull through the verticals much better than I do. But I'm learning from these videos that you are pulling a lot more than me. I keep my loops to around 2.5 gs which for my power isn't enough pull I think. Great video. I wish I could get instruction in my 6a and be in the aerobatic category.

Erik, I was most disappointed i guess by feeling like i'd been improving toward my goal of doing solo acro and this flight kind of felt like i'd take a little step backward rather than forward. I'm going to blame the heat for throwing me off that day
I have an AeroSport Power O-360-A1A. When new it was rated at 200 hp. Now, with 1100 hrs on it i'm figuring that it's not quite that high anymore. I was a bit surprised though to see climb rates pulling up into the loop of 6000'/min.
I'm no expert, by a looooong shot, but loops feel best when i hit between 3.0 and 3.5 G going into them. Maybe Eric S can give us his opinion on what we should shot for, or if it even really matters all that much.

Gene

[TheHDPilot]

Originally Posted by MarkW

Thanks Eric,
I will pay more attention to rudder input during loops.

Just a note on the throttle during the backside of the loop.
My biggest fear of performing a loop in the RV was an overspeed on the backside. I feared that to control the speed I would need to pull excessive G's or allow an Vne.
Now I fly the loop with full throttle all the way around to keep my speed up/the same. Fears were baseless.
Thanks.

Now that I realize everyone is saying that keeping power in all the way around is what i should have been doing all along, i'm definitely going to start doing them that way myself. Thanks for the feedback Mark.

Gene

[sandifer]

Originally Posted by TheHDPilot

I'm no expert, by a looooong shot, but loops feel best when i hit between 3.0 and 3.5 G going into them. Maybe Eric S can give us his opinion on what we should shot for, or if it even really matters all that much.

Gene - for fun flying, you can pull whatever G you like, and whatever gets you over the top. Doesn't matter. If you're interested in doing actual round loops (or close to), 3-3.5G won't work since such a soft pull will produce an initial radius so large that the RV won't be able to maintain enough energy over the top to keep the radius constant (round). Low G loops look like a cursive letter 'L' from the ground. Ron or Bill could tell us exactly what they pull in the RV, but it will likely be more like ~4.5G for a round loop. To fly round loops, pilots must also adjust to much more time spent floating over the top. When coaching new pilots from the ground with round loops, you're pretty much saying, "Pull harder...now float it, float it...not enough float!!".