Reno aircraft movement enabling device

At Reno the Sport class races the RVs that enter ar in the large hangar next to the street that runs by the south side of the airport and there is a no prop turn rule until the plane is spotted on the ramp adjacent to the taxiway a significant distance away (1/8 to 1/4 mile). Tow vehicles operated by the race staff move the planes to the assigned spots. Typically these are tail draggers and the tail wheel is run up an little ramp on the tow bar and it drops into a recess and that is the tow link. That doesn't work with an RV-6A for example. When I was there last year I was not in the race but one of the racers had a structural failure and had to be moved to the private hangar where my plane was being kept at the east end of the hangars and mine had to be moved to the Sport Class Bronze hangar.

When the first tow was completed to move the damaged plane we found two compatibility problems:

1 - the nose gear fairing which has only a 0.75" ground clearance could not clear the tow bar structure to allow the nose wheel to roll up the ramp or drop into the wheel recess without damaging the fairing.

2 - if the fairing was removed (a tedious process involving around 20 screws) the nose strut would not clear the the tow bar structure forward of the wheel recess.

I pressed down on the stabilizer and raised the nos wheel off of the ground and the tow operator backed the tow bar under the wheel and I let it down into the recess. That enabled the long move to be completed but that is not compatible with race operations scheduling, etc. I have developed external covers for other applications and speed mods and I plan to cut a hole in each side of the nose wheel fairing and develop covers requiring only one screw for installation and removal - similar to my fresh air vent covers - to provide access to the axle hardware that people currently use for towing. I would buy one of those tow bars that people currently use, cut off the handle and replace it with a ring or something compatible with the tow vehicle tow connection.

The question is what tow bar is compatible with the RV-6A axle hardware? I want to buy something that is known to work with the airplane and modify it to be compatible with the tow vehicle.

Bob Axsom

You might look into the Universal Big Bogi, PN 04M-BBU, from Bogart Aviation. I just bought one to use with my golf cart to push my Cessna 172 up a ramp into the hanger. I am still building my RV-7A, but the Cessna attachment coincidently works with the RV-7A.
The towbar works great and is well made for the price. Others models that attach to tow vehicles were over $400. Such as the Brackett TH-5.

That has potential

Thanks Bob. I entered the mfr, name and number in a Google search window and got to watch a video. Even if I have to modify it there are a lot of positive features. I would have to verify that the "C" width and depth would accommodate my nose wheel fairing and the sockets would mate with my axle bolt hardware and I would reduce the length probably but that looks like a workable option.

Bob Axsom

There is a problem with the depth of the "C" on my Cessna but the width is quite adjustable. I have to hold the front of the towbar up off the ground or the C hits the front of the wheel pant due to the downward angle. The connection to the cart needs to be nearly horizontal or uphill. However the wheel pants on the Cessna look a bit larger than an RV.
Hope it works out for you. It was my cheapest option for a hitchable towbar.

Tie down rings???

Bob,
Another idea is use a strap between tie down rings and pull it that way if ground is flat.

Hi Bruce

It is flat but I found the folks there to be just a tad inflexible. I planned on strapping the prop but they would not accept that method. With the rigid bar interface they have braking control as well as tow control and steering control. I like your thought on the problem though.

Bob Axsom

Bought a Towbar for RV-6A from ACS

It is made by Bogert Aviation Inc. As with most things modifications for my purpose are required. Drag preventing quick access covers have to be developed for the axle bolt holes, which have to be made in the nose wheel fairing. The towbar needs to be modified to replace the "T" handle with a 3" id tow vehicle connection ring. Must be ready for PRS in June.

Bob AXSOM

When you are modifying the T handle, make sure the towbar is long enough to get a reasonable turning radius on the tow cart. Some of the of the hand towbars are too short and the towcart might hit the prop/cowl even when adjusted to full length. I used to hit my head on the spinner when I used the hand towbar, but Cessna's have a long pointy spinner.
Your solution will definately be lighter weight and easier to carry in the baggage compartment.

I went through my Reno photos for tow interface details and I only found this one of Ernie Sutter's Lancair Legacy under tow. I have none of the rear of the tow vehicle.

I asked Bob Mills about the length of the one they used for the Sport Class tail draggers last year because we improvised one of those last year to tow mine. He wasn't sure but he estimated 4 to 6 feet.

Bob Axsom

More information on the tow bar

Called Bogert Aviation. Guess what? They make an replacement for the extension part which they call a Vbar (that looks like a cross - no idea about the "V" derivation) that they provide a choice of a 2.5" diameter ring or a clevis fitting that is pinned to the end. They will also make custom end fittings so I'm having them ship the stock Vbar with the 2.5" ring and a custom 3" ring separately (after they make it). Now watch, I find out the the tow vehicles have a clevis fitting and I have to order that as well (they are interchangeable on the end of the Vbar).

Bob Axsom

Mine is 6 feet long and that works well. I took the ball hitch off the golf cart and use a clevis with the existing hole. A 7/16" pin works.
If they still have the ball, your 3 inch ring should slip right over it.
Good Luck

In for a penny in for a pound

Thanks for that information I called them back and asked them to add a clevis to the order.

Bob Axsom

The Bogert Hardware

The red and black device is the stock Bogert towbar for the RV-6A. The all black device on the right is the V-bar replaces the short black part of the standard towbar for towing with something gentle like a golf cart. It has the clevis installed in the photo



These are the two ring end fittings I bought for the V-bar. The one on the left is the standars 2.5" id stoch part and the one on the right is a custom made 3" id ring



Close up of the installed clevis fitting installed with the common V-bar interface



Starting the fairing interface penetration with a #40 drill



Rought cut hole



The towbar to airplane interface is 0.757" dia so I plan to open the essential access hole to 7/8" dia.

Bob Axsom

Big holes made













Now to the fiberglass part.

Bob Axsom

Initial fiberglass

I used 4 plies and I was able to do both sides by standing the fairing so all the runout is to the opening at the bottom.









Bob Axsom

I'm curious...why did you cut a hole and then cover it back up?

Yellow Tug

I will have my Tug available during the Races for A/C movment



If you would like to use it shoot me a PM

Maybe this will help clear it up

hydroguy2 said:

I'm curious...why did you cut a hole and then cover it back up?

Click to expand...

The size of the cutout is determined by the area needed for a platenut and access to the axle hardware inside my old style flat sided nose wheel fairing. The underlying fiberglass will be partially removed so that what remains supports a flush cover plate and provides a mounting structure for the single fastener platenut installation. I have some special restrictions with the racing subfairing otherwise I wiuld have installed the coverplate with a piano hinge at the bottom and a camloc fastener at the top.

This is what I wrote as an explanation for Bob Mills at the SARL Yahoo group site earlier today.

As you imagine it will all become clear soon. I just went out and checked the
fairing looks good - wiped off the extra run off epoxy. I plan to cut out two
pieces of aluminum to exactly fit those holes so they will fit down in them and
rest on the fiberglass. The fibeglass in the lower center will be cut outfor
wide open access of the towbar to the axle hardware but a ledge along the
forward and aft edges of the hole will serve as a positioning and support
surface for the cover plate. A platenut will be riveted to the upper part of
the fiberglass which is not cut away. That is why the hole id rectangular
instead of a simple round hole. All of the new fiberglass below the towbar will
be removed - in other words the edge line of the for & aft ledges will continue
straight down and none of the new center fiberglass down there will remain in
the final configuration. So there will be common plane shared by the outboard
side of the new fiberglass, the inside of the original wheel fairing fiberglass
and the inboard sid of the cover plates. That allows my to rivet a 0.016"
aluminum tab with flush rivets to the inside bottom of the cover plates that
will lock in the bottom of the coverplateand inatall a flathead #8 screw through
a countersunk hole at top center of the coverplate into the platenut locking
everything solid with only one screw and platenut location for each plate.
Removal of the screw will allow removal of the coverplate for towbar access to
the axle. If I can find some aluminum of the right thickness the cover plate
will be like an inlaid panel flush with the existing fairing surface and no
increase in drag. There is concern about loosing the coverplates so I should
make spares. Another operational solution would be to invert the covers so they
are pointing up on the side of the fairing exposing the axle fot towbar access
and held inplace by the same mounting screw that is used for securing the plate
for hole closure. The only risk I can see there is mishandling - over
tightening the screw , damaging the paint and/or the fairing or bending the
coverplate.

I hope that makes sense. When it is finished I think it will be kind of an
elegant solution.

Bob Axsom

I should be OK but thanks

Dayton Murdock said:

I will have my Tug available during the Races for A/C movment

If you would like to use it shoot me a PM

Click to expand...

When I was there last year on Bob Mills crew the Ramp Services, RARA or Sport Class (who ever provided the golf cart tows) were always there on time and ready to tow. My problem is getting a system compatible with their system.when this is done I think I will be compatible but there is still a logistical problem or two. The v-bar is so long that the only way I can carry it is from front to back stuck between the seat and the electric flap housing. Not a problem getting out there but I doubt they would smile upon me flying around the course that way. I will have to work something out but the potential for losing part of the towbar is a little bit of a worry.

Bob Axsom

Bob Axsom said:

.....I will have to work something out but the potential for losing part of the towbar is a little bit of a worry.

Bob Axsom

Click to expand...

Label or engrave your name , "N" number, maybe your race class. Then make one of your crew responsible for the tow bar. From what I understand a crew has to be available when repositioning the plane, their job to to bring the towbar back.

I'm betting you'll have a nice usable solution to towing your bird.

One cover done



Still have to do the left side - need sleep.

Bob Axsom

Done!



It came out well.

Bob Axsom

Go Slow

Bob,

Go slow when towing with this type of tow bar. The only thing that keeps the tow bar attached is the "spring" pressure of the unit. Pulling too hard can pull it loose. This can be tough on the paint on your wheel pant.

Tom

Yes I know what you mean.

I may have to come up with a locking clamp across the arms to increase the resistance to spreading. They really towed Bob Mills' plane slow last year and if I were there I could guard against the problem but I may be at a briefing when the plane has to be towed. It is a worey but the guy at Bogert sad it is OK in tow but pushing on an uphill grade is a problem.

Bob Axsom