XP-82 Twin Mustang Project: October Restoration Update

Happy Halloween!

What a month it has been.

Center Section / Fuselages

Ayman, Jeremy and Tim completed all the small to-be-finished sheet metal jobs to be done on each fuselage, i.e., pitot static ports, misc. hi shears, spring swing-out entrance handles, hand grips, cold/hot air ducts, alarm bell, seat mounts, etc., etc.

Spring swing-out entrance handle installed.

They also completed the installation of all the canopy rails along with all the pulley mounts for the opening/closing and jettison systems for both canopies. We also salvaged the right-hand fuselage canopy opening push button and spring door mechanism out of one of the Colorado scraped fuselages. This mechanism allows a person on the outside to open each canopy by pushing the spring loaded button/door to disconnect the locking device in the canopy crank, and then hand push the canopy aft to open.

We have reworked the blemishes in the six aluminum canopy trucks which attach the canopies by rollers to their respective tracks. We have sent the six to QC Labs in Orlando, FL, for NDI (non destructive inspection) for dye-penetrant x-rays and certification papers. The inspection of these trucks is critical because if any one of the three attached to each canopy were to fail in flight, the canopy would detach itself and leave. (Picture next month when they return.)

Tim, “the new guy,” completed the permanent installation of both trim boxes and is currently working on the coolant tube mounts that attach to the floor board mounting structure.

Forward canopy rails, seat mounts and trim box installed

Canopy pulley mounts installed

Aft canopy track installed

Canopy jettison handle installed

Canopy push button release

Weezie and I have been completing the flap tubes that connect each outboard flap through the lower aft section of each fuselage to the large center section flap. The two hydraulic flap cylinders are now mounted, one each side of the center section floor to operate the flap system.

We have also installed the aileron trim mechanism in the left lower longeron bulkhead of the left fuselage. Our prototype XP only had one tab on the left-hand inboard aileron, whereas all the subsequent P-and-F-82s had two tabs, one on each side.

Flap tubes that connect each outboard flap through the lower aft section

of each fuselage to the large center section flap

Two hydraulic flap cylinders are now mounted

Aileron trim mechanism installed in the lower left

longeron bulkhead of the left fuselage

Weezie took another batch of zero-temper wing parts that needed heat-treating up to T-4 condition to Thrush Aircraft in Albany, GA. Thrush has been helping us for years since we started our XP project. Thrush Aircraft manufactures the best agricultural-application aircraft in the world. Thank you, Thrush.

We are waiting for just a couple more bomb/rocket/drop tank fittings from the machine shop. Not having these fittings is not holding up any progress on the wings as they can be installed anytime up to when the last panels of skins are being riveted on.

I have been busy milling the six special long stepped and tapered wing stringers that go into both wings. We didn’t need to buy any aluminum as we were able to mill them out of the cutout billets that Vic (Erie) saved from the center section spar caps. Cutting these random 2” x 3” x 20’ long billets out of the center section spar cap billets instead of turning the required cutout shapes into chips has saved us a substantial amount of time and expense.

Also as mentioned in last month’s news release, we confirmed the washout degrees of our wing(s) by measuring the USAF Museum’s F-82 “Betty Jo” that has the same wings as our XP-82.

Coolant Tubes
Finding the replacement #32 2” and #20 1 ¼” fittings for these tubes was a challenge. I had a few new ones in my Kissimmee stock, B & B Aircraft had quite a few of the #20s and Greg from Avico in Miami was just able to find the remaining new fittings from other vendors.

Coolant tube #32 - 2" and #20 - 1 1/4" fittings

We were able to locate the exact heat resistant quilted insulation fabric with the smooth exterior silver finish to sew our covers for the coolant tubes that run through both cockpits from the engines back to each radiator. Two of our investors, a husband and wife team, have a heavy-duty sewing machine and they are sewing up both sets and matching the beading and stitch edge patterns exactly to the original insulation. (Picture of the quilting to come next month when finished.) Thank you, David and Connie.

All of the coolant tubes are now fit with the new fittings, awaiting final installation.

The restored XP-82 battery box is located on a shelf mounted in the left-hand fuselage just inside the access door aft of the center section flap. Surprisingly, the battery shelf/box and all of its surrounding structure were in perfect restorable condition with no battery acid damage on any of the parts. All of this structure and the battery shelf are now completed, awaiting installation after the control cables and coolant tubes are installed due to access issues if the battery shelf were installed now. Also, mounted on the bottom of the battery shelf is the hot/cold air divider control valves and the battery master relay.

Battery box shelf

Battery Door

Heat Exchangers (Oil Coolers)

We have contracted with the company that built our two coolant radiators, Martin Radiator in Gasport, NY, to manufacture our heat exchangers. These heat exchangers were only installed on H model Mustangs and the first 22 P-82s. There are none known in the surplus market that can be found and purchased, so we must manufacture them from scratch. I was able to save us a substantial amount of money by one of our volunteers supplying the four 7075 T-6 1’ x 1’ x 2.5” aluminum billets to mill the cooler end caps out of, instead of having them pressed for the astronomical figure of $37K. And that’s just for the end caps. One of our machinists is CNC (computer numerical control) milling them for us. Thank you, John and Gerald.

Heat Exchanger

Outboard Wings

Paul and Randall completed the final preliminary set-up on the right-hand wing in the first week of September and are now have almost completed the set-up on the left-hand wing. They have completed the final fitting of all the ribs and the 32 hat channels that go in the fuel tank areas and are now completing the final fitting of all the stringers that run lengthwise through the top and bottom of the wing.