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Converting the RV-7A to an RV-7

Converting 7A to a 7

Need a little advice, Has anyone tried or completed changing a 7A fues already built up to a 7 tail dragger:eek:
 
Quite a few.

Yes...other models as well.
Obviously, it'll take a new engine mount, landing gear legs and the necessary parts rivetted back in the fuselage to hold the tailspring...probably the most difficult part of all.

Best,
 
I converted my 9A to a 9 last spring. Cost was about $2500: new engine mount and gear legs, tail assembly, new brake lines and some bits and pieces. If you got a quickbuild, the tail part is not a big deal - just pull a few rivets, a bit of trimming of the fuselage and put the tailspring in. If you did a slow build and did the lightening of the HS attach bars (F-711C) on the second bulkhead forward of the tail, then you will need to pull that part as well and replace (a bit more work as I understand - mine was QB). You will also probably need to modify the leg fairings - I just added some length to mine with some fiberglass. Probably will need the upper intersection fairings, although I just made mine so that the leg fairings come close to the fuselage and used some rubber stuff (leftover from the wing root fairings) to seal things up.

My engine mount fit the existing holes perfectly, and the cowling worked out so that I did not have to do any modifications on it.

Greg Vouga did a conversion on his 7A a bit over a year ago and was a good resource for me. Cameron Kurth also made a conversion. I can forward you our electronic conversations if you would like. Best to email me directly - my email is available in the user section of the forum.

I'm very happy with my changes, particularly when flying off of unpaved rough strips.

Greg

Obviously, Greg already posted while I was writing - and he needs to change his signature!
 
9a to 9

I have just started with my 9a. On the tail kit, there are references to building the a or not. With no tail wheel experience, my plan has been to build it as an "a". Reading this and seeing that others have made the change, while I am building, are their things I should do or include now to make it easier if I want to change later? I don't know enough about the build at this point to even know if that is a stupid question. I am not asking for a plan of attack or such, just advice on if I should study more or build as is, then modify later if desired.

Thanks
Rockwood
 
Rockwood,

One key thing is to NOT thin the F-711C HS attach bar. Plans say you can trim this down to save a bit of weight on the -A, but it is an important structural component of the TW models. If you have a QB, then it (supposedly) has not been trimmed so you are ok.

I don't think there are any other bits that would be critical. It would probably be easier to drill holes in the firewall now for brake lines, but that's not worth messing up the firewall until you're certain of the change (and even then its no big deal to drill afterward, since you will be pulling the engine and mount off anyway!).

cheers,
greg
 
I've considered changing my 7A.
I don't mean to hijack your thread but this info will probably be of interest to you as well.

For those who've completed the conversion.
1. Did you remove the existing interior gear weldment or did you leave it?
2. Was there much cowl work needed to refit? Add to or trim off?
 
converting to TW

I removed the gear weldments when converting my 9A to TW. I didn't have to do anything to the cowling.
 
With no tail wheel experience, my plan has been to build it as an "a".

Dont worry about no tailwheel experience. The RV is not hard to fly as TW. You can get all the experience you need to be safe in ~10hrs training. Also insurance concerns for low time will only be a consideration for the first year. You will pay an extra $500 or so. If you are like the rest of us it won't be an issue to get 50-200hrs in the first year.

If you build what you want nowyou will save a lot of money and time in the future.
 
I've considered changing my 7A.
I don't mean to hijack your thread but this info will probably be of interest to you as well.

For those who've completed the conversion.
1. Did you remove the existing interior gear weldment or did you leave it?
2. Was there much cowl work needed to refit? Add to or trim off?

1. removed. These are pretty heavy and they stick out on the bottom or the fuse. filling the hole is easier with them removed. I also like the extra leg room in the cockpit.

2. I just needed to trim around the new gear legs and fill the area where the nose wheel came out.
 
Dan,

I removed the weldments. Saves 15 pounds and gives more legroom. Took about a day to pull the wires that were going through it and remove the weldments - not fun but not too bad. Don't need to pull the wing bolts. Cowl still fit just fine on mine after the changeover. Others have noted some minor fitment issues with the different engine mount, but mine seemed to fit perfectly the holes I had drilled in the firewall, and the spinner lined up with the cowl. Filling the nosegear slot was pretty simple with a couple layers of fiberglass, some microbead fill and paint (and its on the bottom so hardly shows).

Cheers,
Greg
 
Dan,

I removed the weldments. Saves 15 pounds and gives more legroom. Took about a day to pull the wires that were going through it and remove the weldments - not fun but not too bad.

Or just cut through the weldments..............to remove the wires. Then throw them away, unless someone wants them bad enough to rebuild. In my 6's case, there was around 30 wires, including trim, etc. And on the 6, the spar holes into the welment are unique to the particular spar drilling.
 
I thought about cutting through the weldments and decided against it since it wasn't that difficult to reroute the wires. Just recently I sold the entire package (weldments, legs, nose gear, motor mount). The weldments are worth about $450 new, so I figured it was worth saving them (and it was).

Greg
 
Conerting 7A to a 7

Thanks all for some really great opinions, Doesn't sound like a big deal to do the conversion. I too perfer tail wheel flying. most of my time is in tailwheel and i just enjoy it. As for Some VAN's attidudes i agree, When building my 8A sometimes i got a guy with a real attidude and as were building the current 9A we've run into it a bit also. All in all i think it's just one person that's just about heard everything from us builders throughout the years and just really needs to move on to a different position out of Tech support.. There's one person i get who is just super good and really helps out allot with no attidude at all. Thanks again all.:)
 
How does the conversion change the CG as related to the W&B?
With my catto 3-blade, I'm prone to aft cg when carrying baggage and low fuel.
 
Dan,

Not sure on the 7/7A, but for the 9 it moved the CG aft. I had to put my battery back up on the firewall. But then, I have an IO-360 in my 9.

Greg
 
CG aft

Dan,

Not sure on the 7/7A, but for the 9 it moved the CG aft. I had to put my battery back up on the firewall. But then, I have an IO-360 in my 9.

Greg

Greg, I am still not sure if I want the 320 or 360. From what you are saying, if I wanted to do the 9 rather than the 9a, the 360 might be a better choice as far as the CG goes. At least if I want to carry up to 75 lbs baggage. So many choices and they all make a difference in ways I haven't even considered!!
 
Greg, I am still not sure if I want the 320 or 360. From what you are saying, if I wanted to do the 9 rather than the 9a, the 360 might be a better choice as far as the CG goes. At least if I want to carry up to 75 lbs baggage. So many choices and they all make a difference in ways I haven't even considered!!

I don't believe there's much weight difference in 320 vs 360. Maybe 5-10 lbs.
More aft cg would really be a problem for me.
Greg, looks like we both have the same engine although I have the forward induction.
 
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Greg, I am still not sure if I want the 320 or 360. From what you are saying, if I wanted to do the 9 rather than the 9a, the 360 might be a better choice as far as the CG goes. At least if I want to carry up to 75 lbs baggage. So many choices and they all make a difference in ways I haven't even considered!!
Just put a heavier crush plate up front and you'll be able to use the full 100# of baggage capacity, even with the 0-320.
 
good suggestion

Just put a heavier crush plate up front and you'll be able to use the full 100# of baggage capacity, even with the 0-320.

That is a good suggestion. I personally believe the 320 is plenty of engine for the -9. The one I flew in out of Rifle Colorado had all the power I could imagine needing. We were off the ground and climbing faster than anything I have flown in except the company Citation Ultra and that doesn't count! It sure makes a C172 or even the C182 feel like a tank. I guess it is always better to have more horsepower, especially with such a small weight increase and not huge cost difference. I guess it is easy to throttle back if you want to increase fuel economy. As of now, I would probably stay with the 320 unless a smoking deal appeared for the 360. And I thought picking a color would be the hard part!
 
Rockwood,

No question the 320 is plenty of engine for the 9. However, I picked the 360 because 1) not much more weight than the 320; 2) can always throttle back (I learned to fly at LXV, so appreciate density altitude and effects on power); 3) cost was within a couple hundred $ of the 320; and 4) there was no prop restriction on the 360.

Another thing to consider is what prop you will be using. I'm using the Sensenich FP prop, which is probably 20 pounds heavier than a composite prop. Alternatively, a CS prop might add a few pounds more to the nose than what I have. An extra few pounds either way on the nose can mean a lot to the weight and balance. And on the tail. At my next condition inspection, I will be moving my ELT from the far back under the VS, to just behind the baggage bulkhead. Should take 4 pounds off my tailwheel.

Also note that 75-100# is a LOT of heavy baggage, unless you're hauling rocks like I sometimes do...

Greg
 
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