R

riobison

Well Known Member
I have a 1998 RV 4 with 180 HP FP and Short Gear. I did not build it but I'm the 3rd owner. Great plane, fun and I can't believe on how economical it is to fly.

Wheel landings are not a problem.

3 pt landings for me are not overly consistent but are acceptable about 50% of the time. Having a cross wind seems to help improve my landings and dropping the tire pressure to 24 PSI does make a difference.

I'm thinking of putting on the 380x150-5 tires and that should give me another 1"in height (poor mans long gear conversion) and with the extra surface area to help absorb some of the bounce or hobby horse tendency that gets my attention the other 50% of the time.

The benefits off airport are a definite benefit for sure.

Has anyone noticed any difference in the landing on paved runways with these tires and the short gear?

Will they fit in the stock Vans 1 piece wheel pants with a minimal modifications?

Thanks

Tim
 
Big Ones...

riobison said:
I have a 1998 RV 4 with 180 HP FP and Short Gear. I did not build it but I'm the 3rd owner. Great plane, fun and I can't believe on how economical it is to fly.

Wheel landings are not a problem.

3 pt landings for me are not overly consistent but are acceptable about 50% of the time. Having a cross wind seems to help improve my landings and dropping the tire pressure to 24 PSI does make a difference.

I'm thinking of putting on the 380x150-5 tires and that should give me another 1"in height (poor mans long gear conversion) and with the extra surface area to help absorb some of the bounce or hobby horse tendency that gets my attention the other 50% of the time.

The benefits off airport are a definite benefit for sure.

Has anyone noticed any difference in the landing on paved runways with these tires and the short gear?

Will they fit in the stock Vans 1 piece wheel pants with a minimal modifications?

Thanks

Tim
Click to expand...

Tim,
I just passed 1000 Hours with the 380's on both my Rocket and RV6X, a home run modification. They do help immensely on soft turf and on pavement. The lateral handling is noticeably better and the larger footprint is also noticeable in strong crosswinds. They fit underneath the stock Van's Pressure Recovery Pants with some trimming. Don't leave home without them...:)

Here is a thread going back to Steve Sampson's blog entry on the Bigger Tires:
http://www.vansairforce.com/community/showthread.php?t=23360&highlight=bushwheels+Rocket

V/R
Smokey
 
PR pants in a weekend?

Hello Smoky

I have the stock one piece pants so I'm not sure if the bigger tires will fit?

The other option is to buy the new style pants but I was thinking to save that as a project for next winter.

Unless of course I can install the new style wheel pants and the new tires over a weekend?

Maybe that's the route to go?

Tim
 
riobison said:
Having a cross wind seems to help improve my landings
Click to expand...

I find this too. I think the tendency to bounce during a "marginal" landing is reduced if some of the vertical momentum is absorbed by the first gear leg to touch down.

The other way to improve landings is, of course, to not do "marginal" ones :D

- mark
 
380/150 x 5 tires...

...will not fit inside the original -6 wheel pants.

The conversion to the PR pants has involved many more hours labor than I anticipated because the parts do not just "bolt-on" a -6. Perhaps I have been compulsive about getting the wheel pants aligned, but I read the part in the instructions about 1/4" misalignment putting the slip-skid ball 1/2 diameter out. Certainly I am slow doing fiberglass work and painting. I doubt that it is a weekend project, although I am certain I would be faster the second time around.

My advice is put it on winter project list.

Larry Tompkins
N544WB -6A'W52 Battle Ground, WA
 
Lining up the wheel pants?

Hello Larry,

I'm a little weak on the fibreglass stuff myself so that will add on time for sure.

I had a 1969 177A Cessna Cardinal that I did all of the Maple Leaf Speed mods on and went from 138 MPH to 159 MPH. I had the shop do the installation but they never went to the extremes of measuring anything and just "eye balled it" Of course I was happy with the performance increase but in the back of my eye I always did wonder how much was left on the table and that we could have gained in putting a little more science and effort into it.

What is involved in the lining up the pants? Are there some directions somewhere that I can read?

Regards

Tim
 
Installing PR wheel pants on a -6

1. You need the installation drawings and instructions for both the -6 and -7.

2. The mounting brackets are different. I found the spacer length between the axle flange and mounting bracket was different and had to be adjusted for length.

3. Do an Anvanced Search for -7 wheel pant installation and you will see the various techniques members used to achieve good results.

4. Some people (like me) use wing jacks and a tail stand to orient the plane to its level flying attitude.

5. Next one has to establish a centerline for the plane and parallel lines for each main gear. Then comes an infinite amount of screwing around until one is satisfied that the pants are level and aligned parallel to the aircraft centerline as well as centered laterally over the tire. Some of us used laser levels for this purpose. In my case, I also built a vertical wall and placed it behind the tail, so I had a vertical certerline for the aircraft as well as the horizontal centerline projection on the floor. No doubt at least several people will deem this overkill and OCD, which I freely acknowledge in advance.

6. The mounting brackets and wheel pants have to be match drilled for nut plate installation. However the contour of the wheel pant and mounting bracket does not match - it is one of those "fiddle around and cuss" jobs.

7. When the wheel pants are installed, the gear leg fairings and intersection fairings have to be installed. Once again, it is apparently important that the gear leg fairings be properly aligned - more "FAAC" work.

8. Finally you will get to the lower intersection fairings, which are bonded to the wheel pants and afterwards split vertically along the wheel pant seam. Lots of fiberglass finish work. You will also have to add a flange to the back half of the intersection fairing (4 total) that goes underneath the front half. Otherwise you will have edges from the back half poking out into the airstream.

8. Finally, you will get to prime and paint and reinstall for the bazillionth time.

I have not finished other "improvement" projects on this aircraft, so I have not flown the "after" flight tests yet. You can see that I will be pretty disppointed after having done all of the above if I don't get the "free" 5 - 6 mph claimed speed improvement.

LarryT
 
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Not that hard...

Ditto Larry.
The One Piece older RV4 pants will not fit over 380's. You have to purchase the newer PR pants which already add 5 knots over the old style, trust me. Winter project for sure, but isn't it Winter now? :)
It can be done easily over a weekend. Read my 2007 thread posted above and Steve Sampson's Blog has excellent photos. Also, below is a photo. I recommend using the Van's PR aluminum wheel-pant brackets as a guide and make yours out of thin chrome moly steel. I did this and they hold up much better on rocks and soft turf. To gauge the height of the pants above the tire, set the tail-wheel on a bucket simulating level flight. Have the rear of the wheel-pant where it meets the tire 4" above the ground. (a 2X4 works great). Then they will clear the top of the tire perfectly.

Speed loss? None, in fact my HR2 gained 5 knots with the big tires and PR pants over the previous 500X5's and Sam James pants. Secrets? My friend Ronnie trimmed the lower pant to contour the wheel (see photo).

Highly recommended!
V/R
Smokey


HR2 installation


My friend Ronnie's excellent trimming...

PS: Landing Issues? Practice makes perfect but I found the best landings are surprises. Fly on-speed. What speed is that? 60-65 KIAS full flaps. 70KIAS No Flap. Most RV folks I fly with land too fast, unless of course they are trying to land at my home strip...
 
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