John & Anne Wiley

Here are photos and info about our Wag Aero fiberglass replacements for 1983 Cessna 172Q Wheel Pants.

Update: see below for new photos of relative fit and a “dry install” on the right main.

They don’t even fit over the tires without spreading them, but I’m told they can easily be spread wide enough to fit without damaging them. Is there some hardware missing that would hold them in the spread position, or is this supposed to be done only by the long tapered nut on the outside of the wheel?

There doesn’t seem to be anything unusual about the diameter or width of the tires on our mains.

Main Tire

Details
Aircraft: 1983 172Q
Tire size: 600-6
Opening: Inside of Wag Aero main wheel fairing = 7.25″x18.25″
Needed: opening width required = 8.5″ (9″ for more margin)

Main Wheel

The fairings look great, painted to match the plane when we bought it, with mounting holes apparently already drilled (though we haven’t tried to position them and confirm this).

Main Wheel Fairing

Tags inside the nosewheel fairing confirm they are the correct parts.

Nose Fairing Tag

Same story with tags inside the main wheel fairings.

Main Fairing Tags

Update 10/9/2010: “Dry install” on right main

First I placed the fairing loosely over the wheel, and you can see that the clearances are tight. The inside of the fairing doesn’t even fit over the mounting plate without spreading the fairing, and that leaves about 1/5″ of the wheel nut sticking out past the outboard side of the fairing. I wasn’t hopeful at this point.

1835 Loosely Over Wheel

Click to enlarge the photo and better read the text. This is with the fairing placed loosely over the wheel with its nose resting on the ground and the inboard edge of the mounting cutout rim resting on the mounting plate. This photo is from behind and slightly outboard to show the tire contact and how far the wheel nut is protruding.

1836 Loosely Over Wheel

This photo is from behind and slightly inboard to better show the fairing mount cutout in relation to the mounting plate. The fairing’s not spread at all, and there’s only light contact between the tire and the outboard rim of the fairing cutout.

I tried to first spread the fairing and slide it down over the mounting plate, but it was nowhere near clearing the brake cylinder. After some struggle and thought, I slid the front into position first. So it started out just like in the photos above, with the nose of the fairing on the ground. Next I began to pivot the rear of the fairing down as I continued to pull the mounting cutout area over the plate. At some point I went to the outboard side and pulled that rim over the wheel nut to keep the fairing roughly aligned with the angle of the mounting plate (inboard). To my great surprise it worked! I was able to position the fairing so that the inboard holes aligned with those on the mounting plate. I then slide wheel nut contact point around until the flat portion near the wheel cutout at the bottom of the fairing was roughly parallel with the ground.

1839 Dry Installed!!

Felt like dancing!  🙂

1838 Mounting Holes Aligned

So now the only challenge will be figuring out where to position the wheel nut before drilling the hole. First I’d loosely install the inboard bolts to hold it in position. Then I’ll need to figure out some way of establishing angle of attack in the yaw plane.

1844 Tire Clearance Outer-Front

Tire to fairing opening rim clearance was good at the outer edge.

1845 Tire Clearance Outer-Rear

Less clearance at the outer-rear, but perhaps half an inch is enough? Only problem area seems to be the inboard-front edge where it comes too close to the tire tread area:

1847 Tire Clearance Inner-Front

The good news here is this area can be cut or ground away. The vertical fairing wall is far from the tire, and this nearly touching area is on the bottom (the part of the fairing in front of the wheel opening, parallel to and facing the ground). I won’t be able to begin increasing wheel clearances until after I’ve loosely mounted the bolts, drilled the wheel nut bolt hole in the outer vertical wall, and loosely mounted that bolt. Then I can more accurately measure clearances, wobble the fairing to its limits in every direction to see what minimum clearances that produces, then mark the fairing and remove it for trimming.

Question: How much clearance is required, and should it be the same minimum everywhere or more in some places?