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Fitting the RV-7 Crotch strap mount into the '6

P

Pittsartist

Well Known Member
I've just taken delivery of 2 of the kits from Vans to fit into my '6

Has anybody done this before ?. Seems straightforward from the instructions .......usually a sure sign it'll be a PITA

Any photos would be particularly helpful
 
Here are some photos of the kit in my RV-6. Pretty straight forward as you mentioned, no gotchas that I can recall.









Sorry I couldn't find any of the pilot's side, but it's the same pretty much.

EDIT: This was not the RV-7 kit. Actually, it was the kit that was originally available for the -6. Would have been way before the -7 kits. Sorry.
 
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what gauge is the material?.....

..if a guy wanted to 'do-it-yerself', looks like just some .060 aluminum bent, is this the case?
also, no reason you couldn't bolt the whole thing? ( I'm doing it on the field, no rivet gun!)
thx
 
flyboy1963 said:
..if a guy wanted to 'do-it-yerself', looks like just some .060 aluminum bent, is this the case?
also, no reason you couldn't bolt the whole thing? ( I'm doing it on the field, no rivet gun!)
thx
Click to expand...

I did mine with the kit from the 7. I have to cut off one of the flanges on the mounting bracket since it was a hair wider than the space between the ribs. I riveted a new flange in its place. The picure in the prior post is missing a few parts of the kit. Here is one installed per plan (except for the modified flange).

FP04102012A00058.jpg

FP04102012A00059.jpg
 
Pittsartist said:
That's great - same parts I have.

Maybe, just Maybe, it IS as easy as it looks ;)
Click to expand...

The install calls for blind rivets to attach to the ribs. To keep the ribs in position I match-drilled some scrap to the screw holes in the floor and then screwed the scrap to the ribs when the floor was removed. This ensured that the 5-point bracket didn't push or pull the rib out of alignment with the floor.

On the side I cut off the flange I used some angle and match-drilled it to the web of the bracket with everything clamped in place. This made it easy to match the spacing of the seat ribs. The mismatch was maybe 1/16", but enough so I coudn't install the kit exactly as received.

Make sure you account the the thickness of your seatbelt attach point, not all are the 1/8" called out n the instructions. The bolt hole size can vary also between brands.
 
I'd like to credit this pic, but I can't remember where on the internet I stole it from...:)

A bolt on approach with a reinforcing plate added to the intercostal bulkheads -

crotchstrap2.jpg
 
Here is the bracket I made for installing a 5-point harness in the RV-6:

5-point%20anchor.jpg


This was done in the hangar, no right-angle drill or rivet gun. There are four pan-head screws on the belly of the plane but they don't bother me. Getting pounded by turbulence does bother me. :)

I modified the floor opening for the stick a little and didn't have to modify the seat cushions. All in all a very nice installation.
 
Good field mod.....poses one question

Nicely done Sam, and I respect your solution.....I had considered something similar, but wondered about the potential load on the floor skin.
Your fasteners are right alongside the floor rib, so considerable load transfer there.
what's the load? would a doubler on the belly skin be advisable?

....maybe an extreme bump could generate an instant of -4g? so a pull of 800 lb before the lap belts start to share the load?
Just running it up the flagpole...appreciate any thoughts on this.
 
The installation shown in the photos of Pats airplane is one I designed years ago and sold with the Schroth 5 point belts he has (I distributed the belts). Not sure if this is now Vans design but I can say that it was load tested for crotch strap flight loads (30% of the lap belts), and was good with no permanent structural deformation. It was positioned to pull straight down against the shoulder belts. The overlap in the center allows for varying spacing between the seat ribs. A very simple installation to copy.

Dan
 
flyboy1963 said:
Nicely done Sam, and I respect your solution.....I had considered something similar, but wondered about the potential load on the floor skin.
Your fasteners are right alongside the floor rib, so considerable load transfer there.
what's the load? would a doubler on the belly skin be advisable?

....maybe an extreme bump could generate an instant of -4g? so a pull of 800 lb before the lap belts start to share the load?
Just running it up the flagpole...appreciate any thoughts on this.
Click to expand...

I thought about the load on the belly skin before deciding to go ahead with the installation. But I'm not doing neg-G aerobatics, just want to be able to cinch down the shoulder straps if the bumps get nasty.

The belly skin doesn't flex when you pull hard on the crotch strap, and worse case scenario if the whole thing let go is I would be left with a fully functional 4-point 3" G-Force harness. But I won't be breaking this mount. :)
 
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Small Thread Creep

Does anyone know who makes Van's harnesses and how to contact?

I contacted Van's and was told that they don't sell just the crotch strap and I already have the 4pt harness (-7).

I was told that info would be sent along with a recent order but it was not.

The mount was already in the fuse, so all I need is the crotch strap.


Glenn Wilkinson
 
the 5th point dilemma...

Glenn,
I'm trying to do exactly the same thing, so here's what I've found so far.
My belts say 'amsafe' on them, pretty sure that was what Van's supplied in 2005 or so. Their site clearly says something like ' 5 point will NOT work with 4 point harness'.
I tried simply attaching on of the passenger shoulder attach tabs to my 4-point, and, well, it works, but there is really no slack left on the lap spade. In fact, about 50% of the time, I couldn't latch it without juggling all the connectors. So it will work, but not reliably in my opinion.
I contacted one of the suppliers that makes the 5th point connection , and they said they were not in stock, but could make me a batch .
P/n RH-54s
These are a special order and are made for the Am-Safe style seat belt buckles and connectors. $20.00 each, 10-14 days. Minimum is 25 pieces. [email protected]


Maybe we should talk to Allan Nimmo at AntiSplat eh?

I'm seriously considering making all cloth loops that attach to the lap belt on each side of the main buckle, kind of like the fancy 6 point 'y' racing belts, and thus do away with the mechanical buckle issue, plus it might be more comfortable if I can get all the geometry correct. ( ie. it will allow a little more 'breathing' room right behind the stick, since that's practically in your lap when full 'up' elevator applied)
 
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Simpson Racing was exhibiting at OSH. Simpson is offer a pretty good rotary buckle harness for experimental aircraft.


Dan
 
RV-7 crotch Strap

glenn654 said:
Does anyone know who makes Van's harnesses and how to contact?

I contacted Van's and was told that they don't sell just the crotch strap and I already have the 4pt harness (-7).

I was told that info would be sent along with a recent order but it was not.

The mount was already in the fuse, so all I need is the crotch strap.


Glenn Wilkinson
Click to expand...

I sent my crotch stap to AM Safe for modification as it was too short to attach. Only infromaton I can find to contact them is as follows:
AmSafe Customer Service Representative is Susan Mathen-Wilson Phone
(770) 228-0712. I belive they are somewhere in Georgia.
The company was very helpful and responsive, and provided prompt service at a reasonable rate.
I would assume that if they modify a crotch strap they will also sell one. If you do make purchase from them I would suggest you obtain longer length that the one they sell to Van. It is obviously made for short slim people and I am not one of them, unfortunately.
 
Thanks for the number.......

They're probably no more than 100 miles from me, I'll give them a call.

Glenn Wilkinson
 
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