brianwallis

brianwallis

VAF moderator
I apologize if this thread has been posted, I could not find it. How hard is it to do the tall man conversion on the rv-4 after it has been built?
Best
Brian Wallis
looking for -4 for sale
add: I'm 6'3"
 
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How big are you?

The tall mod would require moving the seatback to the rear. Not hard to do but it will interfere with the passenger control stick. The top of the pilot seatback rests against the roll bar. You will need to slide the roll bar back by drilling new holes. The seatbelt anchors will have to be shortened in symphony with the seatback. This is all not that difficult.

I am only six feet tall but have long legs and arms for my height. I have to purchase casual dress slacks at Nordstrom because they are the only retailer that has my size; 32 waist / 33 inseam. The stock 4 is a little shorter than I would like between the seat and peddles but I don't want to eliminate the rear seat stick. I am going to use a single, one inch thick Conforfoam pad for the seatback. The medium density is just right. It doesn't bottom out and confirms well. With the thin seatback foam my knees are down and legs are pretty well stretched out.

By the way, Van is taller than me. He is a pretty big guy and still fly?s the factory RV-4 regularly, so I'm told.
 
tall mans rv

I'm 6'3", and I have no problem sitting in a -4. Now I do use less padding than everyone else, but the fit is fine, no problem with the leg room, (I'm 34-36). I also fly my -3,(with alot less padding), with only minor leg issues. If you move the front seat back, you now only have a 1 1/2 place airplane because of the c.g. I know this to be true, because a friend of mine has his -4 set up that way, and he cannot fly anyone over 100lbs. which amounts to a small child, or a very skinny woman.:D Another friend has his set u p according to plans, and he can fly up to 250lbs in the rear seat:eek: The best thing to do is to is to find one to sit in, then decide for your self. Don't give up plans to build! The -4 is an excellent airplane, alot of people have said that it is probably the best design that Van's has out, I for one agree.

Mike Bauer
RV-3 N87LB Flying
RV-4 N742MC oh soooo close
 
Not sure.........

As someone said already, to move the seat you have to move the role bar. This may/may not be possible. On the -4 I am building this would not be possible because you would run out of 'meat' to attach it to. This picture might help:
http://gikonfuse.blogspot.com/2006/06/roll-bar-structure-continued.html#links

This is a part of the build where VANS leaves quite a bit to the imagination, so they will vary. Mine is in the standard position.
This might help also.
http://gikonfuse.blogspot.com/2006/10/front-seat-goes-in.html#links
http://gikonhome.blogspot.com/2006/09/progress-while-my-broadband-service.html#links
(Double click the pictures to get the detail.)

So, my conclusion is you should look very carefully on the -4 you intend to buy, to see if the role bar can be moved. It might be easier if you find the otherwise perfect -4, to have a custom role bar fabricated that would allow the seat to move but utilise the existing holes.

There are more roll bar pictures around my blog somewhere, but its bedtime.

Good luck!
 
Hi Brian!
I'm 6'33" and feel comfortable in my RV4. While building, I started to think about the tall pilot option as well, but there's more do do than simply move the rollbar backwards. At first, you have to re-design the supporting ribs of the rollbar, so they will really support the rollbar after shifting it backwards. Then you'll realize, that the flap-mechanism will get in collision with your seat, as well as the passengers stick, that would not be able to move far enough forward anymore. Some weeks later you'll find out, that the middle bar of your canopy frame will interfer with your rollcage.
I did the following: Shift the rollcage backwards, so that it will just clear the canopy frame, design a very thin back-cushion and that's it. As mentioned, I'm 6'33 and have no problems at all (except in winter my a** has to melt in my conforfoam cushion, so I can close the canopy) :D Easy to avoid if you take some ' more earth-bound cushion material'....

You asked how hard it would be to customize an RV after it has been built, and that will be even harder. If you move the rollcage back and let the supporting ribs as they are, maybe you'll compromize integrity if you really roll it over. The rollbar might simply bent or whatever, because the supporting ribs are way too much forward to do anything good for it. What you can do is this: Normally, the seatback is supported by the rollcage, and rests on it. You can bold it on from the rear side, so you'll get some more space for your main body. All other things will lead to a rat's tail of modifications.
Go on with the -4, it rocks!
 
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tried to sit in one

Does anybody have a tall man conversion rv-4 in the Southeast? I tried to sit in Mr Dunwoody's regular rv-4 but it was a bear... I need to sit in a tall man conversion -4 please... I'll fly or drive to you... and we can talk from there...
Best
Brian
 
Other ideas...

Brian,

I have 'converted' two RV-4s to fit me and and now almost done with my -4 I'm building to fit even better. As a 6'1", 200#, 35" inseam kind of guy, a 'normal' RV-4 can be tight and this is what I've done to better fit when converting a previously built 'small guy' R-4:

-As previously metioned, move the roll bar aft with new drill holes. While this may be only an inch or so, it makes a BIG difference.
-You can also move the bottom backrest hing line aft a bit
-Reduce the backrest seat cushion to minimum thickness. A well designed min-thickness is just as comfortable as a thick one. I have made numerous 7 hour trips to OSH in my old -4 and could have flown back the same day, comfy!
-Bottom cushion is a -4 is usually very thick to make up for spar placement, you can almsot always gain some sitting hight here but as you move the seat lower, you lose leg length so minimize to just one inch (or so) below the canopy top.
-Rudder pedals: You will notice the rudder pedals have a short attachment between the cables and the rudders themselves. This length is almost always able to be lengthened and still give safe full rudder movement (which is IMPOPRTANT!) I have routinely gained an inch or more here.

I have owned a Rocket and an RV-8 which do have inherently more leg room. I currently fly my RV-6 I have fitted for me very well. But just LOVE the flying qualities of the RV-4 so am building one FOR ME! My new -4 is 4 inches further after in seating and I can still get into the back seat. The aft stick had to be slightly modded to fit and have full authority. Since most of my sorties as SOLO I made the plane to fit me....if someone wants to ride, they are usually not paying the $$$$ so can SUCK UP the comfy factor! :D

Hope this helped.
 
brianwallis said:
I apologize if this thread has been posted, I could not find it. How hard is it to do the tall man conversion on the rv-4 after it has been built?
Best
Brian Wallis
looking for -4 for sale
add: I'm 6'3"
Click to expand...

You will need to look at the canopy frame cross bracing as well, this would take more work than the rest I would think.

Gordon Pettigrew
ZK RVG.
 
Canopy xbracing spacing?

Hi all-
I just found this thread as I am considering moving the roll bar back. I want to do so without major structural changes - even half an inch would be better than nothing. How far can I move the roll bar back without interference with the canopy cross brace? Can anyone out there with a standard installation provide a measurement of the distance between their roll bar and the crossbrace?
Thanks,
Eric
 
Maybe 1/4". You're better suited trying to change the way the seat back hits the roll bar. My hangar mates RV-4 sits back about 1.25" more than mine simply because of how the seat back stop works.

Moving the roll bar is a big effort in my opinion. You would have to move the structure below it at the same time and that may require more changes because it's part of the spar carry though structure.
 
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