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  #21  
Old 12-02-2016, 08:32 AM
precession precession is offline
 
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Quote:
Originally Posted by jrs14855 View Post
I sure would like to see someone thoroughly test all the aerobatic RV models for both the Mueller/Beggs hands off recovery and the Finnegan controls centered recovery method.
Great idea, sounds like a job, ideally, for someone with a video recorder on helmet/headset cam, documenting the altitude loss in the RV for each the three recovery methods -- PARE, Mueller/Beggs and Finegan -- as done by world record holder Spencer Suderman here in his Pitts: https://www.youtube.com/watch?v=o-6SzkPNyL8

(Hmm, I wonder if Saber25 has one of those video cam contraptions. )

Thanks, jrs14855, for the additional valuable comment.

And Saber25, thanks, I've been on the aerobatics fun train on my own for a while, doesn't mean I'd be any threat in competition -- which makes your advice that the judges in IAC don't respond to the $100 on the forehead method bad news.

Last edited by precession : 12-02-2016 at 08:46 AM.
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  #22  
Old 12-02-2016, 10:35 AM
sandifer sandifer is offline
 
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Keep in mind that the small differences in recovery efficiency between PARE, Beggs, and "Finagin" are more academic than important from a practical standpoint. PARE is not an emergency recovery technique, so whether you choose to keep Beggs or "Finagin" in your back pocket in the event of a disorienting spin is a matter of pilot/aircraft preference. I prefer to advocate the "Finagin" neutral control technique, since it completely removes the requirement for any decision making whatsoever regarding the direction of the spin. The same technique works for any spin mode.

Regarding the findings of Spencer's video, I don't consider them an accurate comparison between the different recovery techniques. Some of the numbers just don't make sense. I think there are some pilot variables going on here, and more scientific testing would be needed. But again, it's academic unless you're flying an airplane that does not respond adequately to any particular technique. There are certain spin modes in certain airplanes that don't recover with the hands off 'Beggs-Muller' technique. An accidental spin is not the time to become a test pilot. Don't allow yourself to get into a position where 100' or so of altitude difference between different techniques will decide life or death.

I cannot imagine the 'Finagin' method would fail to recover a properly loaded RV from any spin mode, but I've never seen any RV spin test info that covers different techniques across all spin modes. I've never heard of anyone attempting a full power flat spin upright or inverted in an RV. (EDIT - I see 'ALMARTON' posted a video today of a true power on upright flat spin in an RV-7. Looks completely normal, like any other aerobatic airplane. First time I've seen that, thanks for posting. For those running metal props with hollow cranks and/or light crank flanges, be aware that full power flat spins impose high gyroscopic loads.)

Last edited by sandifer : 12-02-2016 at 10:42 AM.
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  #23  
Old 12-03-2016, 09:49 AM
precession precession is offline
 
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Originally Posted by sandifer View Post
Keep in mind that the small differences in recovery efficiency between PARE, Beggs, and "Finagin" are more academic than important from a practical standpoint.
Point taken. As I understand it, and as I think you are pointing out, jrs14855's original point wasn't really about comparing altitude loss amongst the various techniques, but rather to simply obtain proof in the first place as to whether or not the Beggs/Mueller and Finagin methods actually work in RVs -- since you only know for sure once a plane has been tested. It would be interesting to see the testing recorded on video though, alongside of PARE recovery. I'm guessing that when Vans performed initial spin testing they would have used PARE technique.

Last edited by precession : 12-03-2016 at 10:11 AM.
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  #24  
Old 12-04-2016, 07:33 PM
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ssmdive ssmdive is offline
 
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Quote:
Originally Posted by sandifer View Post
Keep in mind that the small differences in recovery efficiency between PARE, Beggs, and "Finagin" are more academic than important from a practical standpoint. PARE is not an emergency recovery technique, so whether you choose to keep Beggs or "Finagin" in your back pocket in the event of a disorienting spin is a matter of pilot/aircraft preference. I prefer to advocate the "Finagin" neutral control technique, since it completely removes the requirement for any decision making whatsoever regarding the direction of the spin. The same technique works for any spin mode.

Regarding the findings of Spencer's video, I don't consider them an accurate comparison between the different recovery techniques. Some of the numbers just don't make sense. I think there are some pilot variables going on here, and more scientific testing would be needed.
I did a test after Suderman's first spin video
https://www.youtube.com/watch?v=ZG-mlDhRt_A&t=16s

What I found was that Begg's recovered faster. My theory is that it just has fewer steps.

PARE
1. Power
2. Ailerons
3. Rudder
4. Elevator

Finigan
1. Power off
2. Neutral controls
3. 100MPH
4. 4G pull out.

Beggs
1. Power off
2. Let go
3. Stomp opposite

I found Beggs allowed 1&2 to be done simultaneously.

I advocate Finagin since putting all controls neutral might actually prevent a spin.

If I have time, I might try the same thing with the 6....
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1986 Pitts S1S - Flying
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  #25  
Old 12-05-2016, 09:43 AM
sandifer sandifer is offline
 
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Quote:
Originally Posted by precession View Post
As I understand it, and as I think you are pointing out, jrs14855's original point wasn't really about comparing altitude loss amongst the various techniques, but rather to simply obtain proof in the first place as to whether or not the Beggs/Mueller and Finagin methods actually work in RVs -- since you only know for sure once a plane has been tested. It would be interesting to see the testing recorded on video though, alongside of PARE recovery. I'm guessing that when Vans performed initial spin testing they would have used PARE technique.
Absolutely right. I sorta side tracked by bringing up the other point, since on occasion folks have a tendency to obsess about using the most efficient technique. I don't think that was happening here. It's more important to pick the technique that simply works period (for your airplane) and is most likely to be employed successfully by the pilot if needed.
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  #26  
Old 12-06-2016, 08:13 PM
precession precession is offline
 
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Quote:
Originally Posted by ssmdive View Post
I did a test after Suderman's first spin video
https://www.youtube.com/watch?v=ZG-mlDhRt_A&t=16s

If I have time, I might try the same thing with the 6....
Very nice video. My -4 is down for exhaust system repairs, otherwise I would already have tested the Beggs-Mueller and Finagin recovery methods and reported (albeit without video, which I don't have).

In your video, you let the aircraft spin for 1,000 ft altitude loss before starting recovery inputs, which seems like a reasonable way to try to set the same parameters for each test. I guess another option would be to pick a set number of rotations. I think I counted about 6 rotations during your first 1,000' altitude loss. I'm assuming you held full in-spin rudder, but do you happen to remember what other control applications were you holding during the first 1,000', in terms of: power, aileron, elevator? I'm guessing you left in some power. I think when I test Beggs and Finagin (sp?) I'll just start out with a 2 turn spin while holding full in-spin rudder, partial power, full aft elevator and neutral aileron. The thing with the -4 is, if you leave any power in it seems you have to keep the nose up at a ridiculous angle to get it to stall - just wants to keep flying (great airplane).

Last edited by precession : 12-06-2016 at 10:49 PM.
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  #27  
Old 12-07-2016, 07:52 AM
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ssmdive ssmdive is offline
 
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Quote:
Originally Posted by precession View Post
Very nice video. My -4 is down for exhaust system repairs, otherwise I would already have tested the Beggs-Mueller and Finagin recovery methods and reported (albeit without video, which I don't have).

In your video, you let the aircraft spin for 1,000 ft altitude loss before starting recovery inputs, which seems like a reasonable way to try to set the same parameters for each test. I guess another option would be to pick a set number of rotations. I think I counted about 6 rotations during your first 1,000' altitude loss. I'm assuming you held full in-spin rudder, but do you happen to remember what other control applications were you holding during the first 1,000', in terms of: power, aileron, elevator? I'm guessing you left in some power. I think when I test Beggs and Finagin (sp?) I'll just start out with a 2 turn spin while holding full in-spin rudder, partial power, full aft elevator and neutral aileron. The thing with the -4 is, if you leave any power in it seems you have to keep the nose up at a ridiculous angle to get it to stall - just wants to keep flying (great airplane).
Set up for all the spins was the same. Power to idle, add elevator till it breaks, full rudder and then full elevator, neutral ailerons.

You could do number of spins, but then you have to count them. I found watching the altimeter was easier and since altitude was what I was recording, I tried to keep it easy. If I was recording number of turns to stop, I would have counted turns.

Don't know if that makes good sense, but it made sense to me.
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  #28  
Old 12-13-2016, 06:54 PM
precession precession is offline
 
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Default Spin Test Results

Hey guys, as a follow up to the above, just wanted to report that I got my -4 back in action and had a chance this afternoon to see how it responds to the Finagin and Beggs/Muller spin recovery methods. (B/t/w, in case others out there have already tried them, I'm not trying to claim I'm the first.)

So the bottom line is simply that I found that both of these methods do work to recover from spins in the RV-4. The -4 responded very quickly and immediately to each method, IMO, and it worked for spins to both the left and right.

My initial spin inputs were (a) power off, (b) full in-spin rudder, (c) full aft elevator, and I held those inputs for 2 full revolutions before initiating recovery. I actually started off using the P.A.R.E. method, then moved to Finagin, then Beggs/Muller. I did each one two times right and two times left (then had to stop, it was getting dark).

With both P.A.R.E. and Finagin, I was back to level flight after an altitude loss of @1,000' (that includes the 2-turn spin before the recovery inputs were applied). With Beggs/Muller, I was back to level flight in @1,300-1,400' (again, that includes the 2-turn spin before recovery initiated).

I wouldn't put a great deal of stock in the altitude loss figures because my technique probably could have been better, and it was actually the first time I've done Finagin and Beggs. Nevertheless, I think the Beggs method took a little more altitude just because I made sure to follow the procedure, which is to wait for rotation to stop before pulling out of the dive, and it seemed like the plane had to come out of a little steeper of a dive with that method.

I'll probably try some other variations of these tests in the future.
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