C

Captain Avgas

Well Known Member
Has anybody done an inverted spin in their RV7(A).... either deliberately or inadvertently. Many aerobatic planes will not sustain an inverted spin unless positive control pressures are applied...they just end up in an inverted spiral dive. Does anybody know if this is true of the RV7(A).

I asked this question on another aerobatic thread and the line went silent. I'm guessing that not too many RV pilots know the answer to this one...but if they're out there doing aerobatics then they probably should.
 
Lack of authority.

I doubt you would have enough forward stick authority to even stall it.
Now Bob, get back to the workshop. Mine's at the painters.
Pete.
 
Lack of spin knowledge

There has of today been 278 viewings of this thread and not one person appears to know anything about the inverted spin characteristics of the RV7.

It's a bit of a worry actually.
 
It might not be that surprising. I've read of quite a few RV'ers doing acro in planes that they've never spun (right side up) and many who've said that they're unsure of the plane's ability to recover from a spin should it occur. I also saw a quote here the other day describing doing cubans while maintaining positive g. Huh?! Some folks come to acro through dedicated training and some come to it through trial, error, and some luck. I suspect there are more than a few RV'ers in the second group. I don't claim to be an expert on acro, especially in an RV, but what I do know is that the most important thing is knowing what to do when things don't go to plan, like an unexpected spin. I think your question is a good one and have been waiting for somebody to sort it out.

If everybody will promise to be careful while flying their RV's, I'll promise not to put a drill bit into my finger again while building mine.


Steve Zicree
 
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szicree said:
I also saw a quote here the other day describing doing cubans while maintaining positive g. Huh?!
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Steve,

Ditch the notion of perfect lines, and you can perform a heck of a lot of aerobatic maneuvers while maintaining positive G.

I was taught to do Cubans by freezing the nose on the 45 down line, which in my plane (no inverted oil system) would cause oil pressure to dive, probably chucking oil out the breather.

When I do "Dan's Positive G Cubans" in my RV-7, instead of freezing the nose on the 45 down line, I arrest the pitch slightly and do a positive G aileron roll. The nose stays on the point, mostly, but definitely not in any fashion that would score points from an IAC judge or whatever.

)_( Dan
RV-7 N714D (705 hours)
http://www.rvproject.com
 
Ditto what Dan says. I have training flying inverted, but it's a comfort level thing (even though the acro plane I fly happens to have inverted fuel and oil system). I just plain don't like all the blood rushing to my head. Other than Hammerheads (where you're a couple of ticks + or - of 0 G's in the direction that matters) I keep everything mostly positive, and everything come out fine.

I'm sure they look sloppy from the ground, but I don't seem to mind and my passengers appreciate the comfotable ride (and yes, we where parachutes :) )
 
szicree said:
It might not be that surprising. I've read of quite a few RV'ers doing acro in planes that they've never spun (right side up) and many who've said that they're unsure of the plane's ability to recover from a spin should it occur.
Steve Zicree
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Steve, quite right. I keep bumping into RV pilots who dabble in aerobatics but have no aerobatic endorsement. Usually they have never tried a real spin recovery. I can tell from their eyes that they don't want to go there....they think it's a bit like travelling to the edge of the flat world...they might fall off (and they might!).

It perturbs me somewhat to consider that their first attempt at spin recovery might be in an inadvertent spin.

I've heard of some pilots wearing chutes in sliding canopy RVs. But as far as I can see, unless you have a quick release tip up canopy, you can't get out. Talk about false comfort.

The whole chapter on RV spin recovery is a bit of a dark unspoken area as far as I can see. It's a bit like the sordid uncle in the family that no-one wants to talk about.

Having said that, my hat's off to Dan Checkoway who not only tested the envelope on spins in an RV7 but documented it on his site with a video. Really good stuff Dan.
 
Bob Barrow said:
I've heard of some pilots wearing chutes in sliding canopy RVs. But as far as I can see, unless you have a quick release tip up canopy, you can't get out. Talk about false comfort.
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I don't know about that....

Has anyone tried to open a RV sliding canopy in a spin condition? With different airflow charateristics, perhaps it might be easier, or harder?

And FWIW, I've done many spins, including inverted in a Pitt's, and would go all out, for a spin recovery in an RV, Just haven't tried it though.
 
Bob,
The RV series of aircraft spin just fine. The side-by-side models turn quite rapidly after about 2 turns and require at least 1 1/2 turns to recover. The tandum models do not exibit this characteristic. As far as no one being familiar with inverted spins, Van recommends "sport" aerobatics only in his airplanes. If you need to do inverted spins, I would recommend that you consider something else.
Mel...DAR
 
Mel said:
Bob,
The RV series of aircraft spin just fine. The side-by-side models turn quite rapidly after about 2 turns and require at least 1 1/2 turns to recover. The tandum models do not exibit this characteristic. As far as no one being familiar with inverted spins, Van recommends "sport" aerobatics only in his airplanes. If you need to do inverted spins, I would recommend that you consider something else.
Mel...DAR
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Mel, let me re-phrase the original question: Can you enter an inadvertent inverted spin in an RV7A (say falling out of a botched stall turn). And if so, will the aircraft remain in the inverted spin until recovery technique is adopted...or will it simply fly itself into a dive. Many aerobatic aircraft will not maintain an inverted spin without positive control pressures...is that also true of an RV7. Does anybody know. That is the question.
 
Every plane is different

Wow, this is fraught with the possibility of people coming to false conclusions. Mel, I wouldn't answer if I were you! :rolleyes:

Just because one "RV-x" does such-and-such when you put it into an inverted spin somehow, that does NOT necessarily mean your RV-y will do the same. They're all a little different in their quirky little ways.

IMHO, nobody should draw any conclusions about how your RV will behave until/unless you test it specifically. Otherwise you've got a potentially invalid comfort level, or on the flip side, unnecessary fear.

Get your training, do your flight testing however you see fit, and be careful out there!

)_( Dan
RV-7 N714D (706 hours)
http://www.rvproject.com
 
You Guys !

We're not even allowed to do ANY aerobatics in the UK in the 6, 7 and 8 thanks to the cretins that run our version of the EAA. We are not allowed to spin them, fly in cloud, fly at night, we sometimes wonder if it's all worth it ?

It is :D
 
Inverted Spin

There have been many aerobatic pilots in pure acro planes spin to the ground inverted. When spinning we know to drill. Part of spin recovery is push on the rudder opposite of the spin. When nose low inverted it is easy to get disoriented and push on the wrong peddle. Remember the anti-spin rudder will have more pressure to push. Even one fatal accident happened with a spotter telling the pilot which rudder peddle to push. I personally don't think inverted is much fun and the RV wing is not well suited for it, but I have friends that love to flip over on their RV back and fly formation upside down.

Great academic question but the RV is NOT a GREAT aerobatic plane, Yea I said it. All RV models are great Gentleman's acro planes. loop/roll/stall are good but competitive acro, no. I am sorry but if you want a real acro plane get a partnership with 2-4 pilots and get a used: Pitts/Zlin/Extra/Sukhoi/Giles/Edge/CAP

http://www.pilotfriend.com/aircraft performance/aerobatic aircraft.htm

Even a low performance acro plane is better in many ways because they have greater drag and can hold a down line longer with out over-speed. I am no expert; I have don't all I want in my RV with out inverted fuel/oil. I would like to own a pure bread acro plane and have flown a S2 once, but owning two planes is out of the question. I am not going to get rid of my RV. The RV does enough acro to make me happy while having all the other characteristics I love, as well as a fast X-C ride. Don't get me wrong, I have seen Van himself do a low level acro performance in the RV-4 at an airshow, and it was a thing of beauty (no inverted spins though). I don't think he is doing airshow routines anymore? Too bad because it was fun to see. RV's are great Acro planes with in limits but inverted maneuvers are not the RV's strength.

G
 
Inverted spins

I've had the pleasure (?!) of doing many inverted spins in various Pitts, just for fun and in competition. Still own an S-2A and usually do an inverted spin (and upright) every flight in that plane when the ceiling's adequate. I think it's unlikely that someone doing recreational acro in an RV will end up in one. But if it's your first, it would be disorienting and dangerous. So it seems reasonable to get instruction in both upright and inverted spins (normal, accelerated and flat) in a plane built for that type of flying, equipped with inverted fuel and oil systems. My RV-8 won't have either, and I'll fly it almost completely positive. But it's nice to be able to recognize the inverted spin and know how to deal with it. Having never spun an RV, I wonder if Gene Beggs' hands-off and push the stiffest rudder works in RV's (realizing they are all a little different). It works beautifully in all the Pitts but doesn't work in a T-6 after a few turns. Anybody out there tried that in an RV? Bill
 
With the greatest respect, most of you are talking rubbish. I want to know the answer to Bob's question, it doesn't seem like there is a whole lot of inverted spinning RV experience out there. I have some experience of inverted spinning (intermediate level acro), and completely agree with Bill - if you don't have any training any spin is disorientating but an inverted spin even more so. However, in my experience (Pitts & Extras) aircraft recover more easily from inverted spins than erect - I know these are not RVs, but many of the factors still apply.

There is nothing inherently dangerous about inverted spins, over erect spins. Saying there is just perpetuates the myth. Experimenting with either without thorough training is a recipie for disaster.

If anyone has inverted spinning RV experience, please speak up!

Pete
 
I have flown an RV outside the UK where we could explore spinning. It was an RV6, fixed pitch, 160h.p.

We did several erect spins, 2 up, medium fuel load.

Standard recovery was perfectly normal, Muller - Beggs worked fine, came out after a turn and a half after being in for 3 turns.

Finally, I just let go - guess what, 2 turns later, it recovered into a spiral dive !

I wouldn't ever contemplate inverted spins, or high energy maneouvres in an RV, they are just not designed for it. be guided by the instructions provided by Van - if you want more, build or buy something exotic. Wouldn't buy a CAP 232 just at the moment though, even if it is really cheap :eek:
 
mike newall said:
I wouldn't ever contemplate inverted spins, or high energy maneouvres in an RV, they are just not designed for it. be guided by the instructions provided by Van - if you want more, build or buy something exotic. :eek:
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Very interesting report thank you. It is noted however that Vans does in fact approve the RV7 for snap rolls to 100 kts. I think it might be fair to suggest that a snap roll is a fairly "high energy" maneouvre, possibly more high energy than an inverted spin.

However we still await an answer to the original question.

Incidentally, this thread has now skyrocketed to 600 viewings in 4 days. As I suggested earlier there's obviously not a lot of real RV spin experience out there....but there's a lot of people interested in (or worried about) the RV7s spin characteristics.
 
Hi Mickey,

Well, if you can stand the risk of it turning inot a boat anchor, fair enough. I think they will come up with a fix to the problem but as you plunge vertically downward at lots of knots with an 8 or 9g push in front of you, just before the ground bit - will you still feel happy ?

Steady progress on ours, inside is painted, first electrics staring, fuel, brakes etc done, flaps next.
 
cap 232

as you plunge vertically downward at lots of knots with an 8 or 9g push in front of you, just before the ground bit - will you still feel happy ?
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I have to confess I would not do this until the investigation is complete! ;)
 
Cap 232

Geez...wasn't the dude pushing like -7 or -8G's? Now okay, the thing is rated for +/- 10, but for a bunch of guys that won't do an inverted spin it seems pretty funny to be scared off by having to keep the - g's down to -5 or so until they straighten this out. LOL.

If anyone doesn't want their Cap232 anymore, just let me know :)

edit: This is a little off topic, but does anyone know anywhere in or about the Antelope Valley where they do acro instruction. I like to go up with an instructor a couple of times a year just to keep me from developing bad habits, but Barnes avaition (out of WJF) is too cheap to get their chutes repacked, and now they're all uncurrent. I don't mind buying a chute for myself (and maybe someone has a recommendation for one that'll work well for the RV so I don't have to buy one twice) but I'm NOT buying one for my instructor :)
 
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Inverted spins

Penguin's right; inverted spins generally recover easily in conventionally designed airplanes. The Pitts recovers briskly, even with full throttle in a flat inverted spin (we keep power up in winter to avoid shock cooling). The problem comes in confusion as to which rudder do I push? - or the direction of the spin. Right rudder in an inverted spin creates rotation (roll) to the left, and vice-versa. If you're a little confused and put rudder against the rotation, you are putting a pro-spin force in, instead of recovering. Your sense of direction of rotation can be thrown off as well if you look too far upward in an inverted spin. There's also the risk of oscillating between upright and inverted spins by giving up on an input too late (failing to realize the spin's stopping) or simply changing the controls too quickly because recovery doesn't seem to be happening as rapidly as you'd like. The IAC mag had descriptions of one such accident in a Pitts where the elevator went from up to down and back again a number of times while the plane continued spinning inverted all the way to the ground. The whole event was videotaped. I've never spun an RV upright or inverted but if you did enter an inverted spin (with no prior experience) and somehow recovered, you might well push 4 or 5 g's recovering from the dive. The newer Vans' designs are engineered for -3g's, ultimate -4.5 (Vans' info). Apparently the RV-4 wing spar is structurally more symmetrical; maybe it can do 6 neg (9 ultimate). The RV-7 spars I've heard (and ? RV-8) have different top and bottom caps, and aren't symmetrically strong for + and - loadings. It wouldn't be too hard to have a structural failure if you pull/push too hard in a survival situation at high speed. If you get the "21 Years of The RV-ator" book read about a builder who modified an RV-4 and flew successfully in Advanced competition where inverted spins are part of the mix. I forget his name, but he could certainly give some info on how that airplane spun. ... just looked it up - his name is Ralph Ridell and his article appeared in 9/91 (page 350 in the 21 year book). Your concern about getting into an outside spin is warranted. While it's unlikely, I did it the first time I took a passenger up in my S-2A (in 1981). Hot day, 220 lb pax, and too much forward stick in a hammerhead. The recovery was quick and straightforward since I'd been trained in inverted spin recognition and recovery, but my jaws were still tight that day. Good luck to you and do get some spin training. Bill Dicus
 
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