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Wheels Pants & Leveling Longerons on a Completed RV-8

I bought an RV-8 with some torn up wheel/pressure recovery pants about a year ago. They were bad enough that I just chucked 'em. I figure it's time to craft some new ones and take advantage of the reduced drag. I have all the components ready to fit over the wheels and start locating holes and align them, but I'm not sure how to safely get the longerons level given that I've got a fully built aircraft. Searching through the threads on here has revealed a lot of advice for builders in intermediate stages, less so for folks doing an alteration.

Anyone have any advice as to how to best accomplish this? Advice about the pants and associated intersection farings would be much appreciated too!
 
I bought an RV-8 with some torn up wheel/pressure recovery pants about a year ago. They were bad enough that I just chucked 'em. I figure it's time to craft some new ones and take advantage of the reduced drag. I have all the components ready to fit over the wheels and start locating holes and align them, but I'm not sure how to safely get the longerons level given that I've got a fully built aircraft. Searching through the threads on here has revealed a lot of advice for builders in intermediate stages, less so for folks doing an alteration.

Anyone have any advice as to how to best accomplish this? Advice about the pants and associated intersection farings would be much appreciated too!
Jack the plane using the wing tie downs and jack points, you MUST hold down the tail. Jack until wheels are lifted and longeron level in pitch and roll.

Vans pressure recovery pants recommended. Fairings from Vans or Cleveland Tools.

Recommend an alignment jig to sit under the wheels to get the pants perfectly aligned. Mike Starkey had one, https://vansairforce.net/community/showthread.php?t=68674.

Also recommend you purchase the digital plans with instructions from Vans. Just call and use your serial number as reference.
 
Thanks Bill! I've got jack points in the tie down points. If I understand correctly, I can use the canopy rails as the longeron from which to measure with a digital or bubble level to confirm that I'm at level. Since I'm working on a tail-dragger, the tail is going to have to come up to achieve level longerons, right? Should I tie the tail-wheel strut to a bucket of concrete and slowly let it up to get it to level? Or am I misunderstanding?

Luckily the engineer/test pilot who build her was meticulous and provided me with full build instructions and a set of plans (both the full size and book size). And I've already purchased vans pants and fairings and put in the time fitting them together. Thanks for the recommendations!
 
As Bill mentioned, When the 8 is jacked up using the tie down locations and you raise the tail level, it will become nose heavy. Be sure to add at least 75 pounds of weight to the tail. Conveniently, 3 cases (dozen qts each) of oil is about 75 lbs which you could stacked on the horiz stab. Another way would be to tie the tail down to the appropriate weight.
 
I lifted the nose using a strap on the engine mount and built a couple square columns of concrete blocks under the center section, topped with a 2x4, then shimmed the 2x4 to level. Blocks were the fastest, cheapest stable thing I could think of.
Also used a stack under the tail and strapped it down to the lowest blocks.
Worked for me. Was up there for months, and the tail still is. (On the gear now and doing FWF stuff)

The way construction materials have skyrocketed here, I could probably sell for a profit!
 
Thanks Bill! I've got jack points in the tie down points. If I understand correctly, I can use the canopy rails as the longeron from which to measure with a digital or bubble level to confirm that I'm at level. Since I'm working on a tail-dragger, the tail is going to have to come up to achieve level longerons, right? Should I tie the tail-wheel strut to a bucket of concrete and slowly let it up to get it to level? Or am I misunderstanding?

Luckily the engineer/test pilot who build her was meticulous and provided me with full build instructions and a set of plans (both the full size and book size). And I've already purchased vans pants and fairings and put in the time fitting them together. Thanks for the recommendations!
Longerons - yes use for the leveling
Tail weight, yes, weight then adjust as needed.

I find the tail weighting tricky for my -7, and use an HF transmission jack with a sturdy stand to sit under the stinger. I have 150# of surplus barbell weights and use a strap over the stinger as close to the fuse as possible. I have not used the Starkey method on the pants but made the jig for my extra set of pants. It does solve many (if not all) the challenges of fitting the pants straight with the longerons that I had fitting my James pants. IMO more weight is good as it is a balance. If the weight is too little . . think about what happens, it won't stop until the wheel hit the ground. Lifting at the engine is good, but puts stuff in the way of getting the job done on the floor.

If you interested in speed, (really?) look at DanH posts on galoshes for the wheel opening. He molds a flexible rubber boot around the pant/wheel gap for drag reduction. Now is the perfect time to do this.

A laser line will be a great help for all the alignments layouts. The plans explain this very well. Have fun with this, it is a typical builder project and you should have some fun with it. The more fun you have the better it will turn out and faster it will go.:D
 
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