The Corsair82: 82% F4U-1A Corsair

Main Gear Two - Pic 1
The next step in the process of developing the main gear system was to build a working prototype in the gear well mock up.
Main Gear Two - Pic 2
I basically started all over again. The prior prototype worked well, but did not fit in the wing. Once again, I built a PVC strut and installed it in the wing.
Main Gear Two - Pic 3
I had to rebuild every part except the universal.
Main Gear Two - Pic 4
I was able to refine the design to work better than the second prototype.
Main Gear Two - Pic 5
While building this third prototype, I dissected a gear strut from a Beechcraft Baron. I would use the Beech design for the inside of my upper strut. This would allow me to use a Beech lower strut assembly (with some modification) and off the shelf internal parts.
Main Gear Two - Pic 6
Now that I had all of the parts and sizes worked out (some parts were built as many as 8 times) I drew up my design and went to a machine shop. After many planning sessions with the shop owner, the materials were procured.
Main Gear Two - Pic 7
Here is the new upper strut next to the Beech strut. It is about six inches longer without the lower strut. The lower strut is still seen in place on the Beech strut.
Main Gear Two - Pic 8
This is the top rotating collar.
Main Gear Two - Pic 9
This is the top cone that attaches to the universal. (if you remember, on my second prototype this part was a snail can and a pipe) This part is inserted into the strut and holds the piston in place.
Main Gear Two - Pic 10
The new strut with the cone and universal.
Main Gear Two - Pic 11
These are all of the parts that will make up the new strut.
Main Gear Two - Pic 12
I had to modify the lower strut so I could use a different size wheel.
Main Gear Two - Pic 13
I had to extract the axel.
Main Gear Two - Pic 14
This is a Cessna 310 gear strut. I need the axel and brake mount from this gear.
Main Gear Two - Pic 15
These are the harvested parts.
Main Gear Two - Pic 16
I traced the Cessna brake mount onto the Beech mount, then cut the Beech part to size.
Main Gear Two - Pic 17
I then welded the Cessna part in place.
Main Gear Two - Pic 18
I then pressed the Cessna axel into the Beechcraft strut. I am sure glad both axels were the same diameter.
Main Gear Two - Pic 19
Here is the assembled new strut next to my PVC prototype. Should it be called a Beechna or Cesscraft landing gear?
Main Gear Two - Pic 20
The new universal is installed in the gear well.
Main Gear Two - Pic 21
The rest of the strut fit right into place.
Main Gear Two - Pic 22
I found that the smallest hydraulic cylinder I could get with the required extension, was about 4" too long. I had to move the wing spar back 4".
Main Gear Two - Pic 23
I had to resize the gear forks.
Main Gear Two - Pic 24
This exercise really helped me to understand the geometry that makes this system work. I can't explain it mathematically (yet), but I now know the relationship each part has to the others, and how to adjust to make them all work together. I put 200 hours into installing the new strut and resizing the forks and retract parts.
Main Gear Two - Pic 25
These are the parts that make up the support/retract system.
Main Gear Two - Pic LA-1
My lower arm design.
Main Gear Two - Pic LA-1.1
The Lower Arm being made at the machine shop.
Main Gear Two - Pic LA-1.2
Taking shape.
Main Gear Two - Pic LA-1.5
Now there are two.
Main Gear Two - Pic LA-2
The Upper Arm design.
Main Gear Two - Pic LA-2.2
Just getting started.
Main Gear Two - Pic LA-2.3
Looking Good.
Main Gear Two - Pic LA-2.6
Now there are two Upper Arms.
Main Gear Two - Pic LA-2.7
Bushings to be installed.
Main Gear Two - Pic LA-2.9
Nice work Al.
Four videos are available of the gear in action. You can view them here.
Download Video 1
Download Video 2
Download Video 3
Download Video 4


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