hangar doors

Bud Fritchley came up with this design with a little help from Steve Blankenberger and a few others. Mostly these were Bud's doing.

Background: This T-hangar was never designed to accommodate doors. The roof trusses aren't beefy enough to handle the weight of a typical bi-fold door and if standard sliding doors were added to the exterior of the building, rainwater would run down the inside of the doors since the roof has no overhang. Also, standard sliding doors always block the adjacent hangar when open. And you can't open adjacent doors at the same time. Yuck.

Bud's solution: These novel doors consist of 8 panels. The outboard panels are hinged to the vertical posts that support the walls, i.e the yellow part of the building.

The inboard 6 panels are divided into 2 sets of 3 panels. The 3 panels are hinged together and roll on a track supported from the roof trusses.

All of the doors on all 8 hangars can be open at the same time with no interferences.

....the interior reveals a curved track on each side of the hangar bay. You can also see the 2"x8" doublers that were added to reinforce the roof if you look just above the track on the left side of the picture.

Notice that there aren't any door tracks on the ground, just the drop down pins that pin the door to pipes driven into the ground. That way there's nothing to get full of dirt or rocks.

As you can see, the doors are made from SQUARE STEEL TUBING. This is critically important for several reasons.... strength, weight, cost, weight, longevity, weight, weight, and weight! A group at another local airport decided to copy these doors and substitute wood for steel tubing. Not only did they spend more, their doors work very poorly, sag, and are very heavy which makes them hard to roll.

I was at our airport last Friday (3-29-2002) during a severe thunderstorm and witnessed these doors withstand a direct wind that blew down several trees and tore off several barn roofs in the immediate vicinity. Very reassuring, knowing my brand new Rocket is safe behind these doors.

Here we see the outboard panel that is also the entry door. You can't see the pin that holds it open. It's just like the other pins that hold the bottom of the doors in place when closed.

The important thing here is that the swinging door does not interfere with the curved track.

The 3 panel sections roll around the curved track and end up parallel with the swinging door.

When all the doors are closed, this simple trailer jack is used to make sure that the roof isn't supporting the weight of the doors. It is welded to the door frame at the center opening. I forgot to take a picture of the top of the door directly above the jack. There is an adjustable bolt that has a small plate welded to the top of it. The plate is adjusted up or down so that it barely clears a pad attached to the center rafter truss. When the jack raises the door, the pad contacts the rafter and effectively forms a center post that supports the roof. How simple! How cool!

Even though the steel doors are relatively lightweight, they would eventually make this roof sag. The jack eliminates this worry.

Although I really don't have any more info than what is shown here, if you have questions, contact me and I'll try to answer. (No, I won't build you a set!)

Vince Frazier
vfrazier@usi.edu
812-985-7309 home... good luck
812-464-1839 work... best time to call M-F in the morning

As far as I know, the tracks are available at most decent farm supply stores. I think the curved sections were the toughest to find, and the most expensive.

The fun part is figuring out the exact size of the panels so that the doors all nest against the side walls when open. Not difficult, but necessary for a good installation. Sorta depends on what the curve radius is.

http://www.mcmaster.com/ search on door track. the curved sections are on p. 2724

They are GREAT doors. No complaints whatsoever!

CAUTION: This web site is not a publication of, nor approved by, Harmon LLC, Team Rocket, Van's Aircraft or any other person or entity listed herein, except me. Be advised that I am a blithering idiot with neither brains nor money and my advice is not to be trusted. So there. You have been warned! Vince