Sunday, November 1, 2015

October XP-82 Twin Mustang Restoration Update

Our XP-82 Twin Mustang is really starting to take shape
and look like an airplane now! 

Engines and Accessories
Both engines are now permanently installed with all of their OHC accessories mounted, minus one vacuum pump and one generator, both will be received and installed next week.

Exhaust stacks are installed on both engines

Also, both MT Propeller governors are installed. One MT Propeller hub and spinner backing plate has been test fit on the LH engine prop shaft and has a microscopic interference with a small governor screw and feather fitting. A little deeper countersink of the screw and fitting will correct the interference problem.

MT Propeller Blades (8) and Hubs (2)
I am making arrangements with MT for both propellers to be delivered to MT’s U.S. base of operations in DeLand, FL. One of their German propeller technicians will assemble both four-bladed props and I will carry them back to Douglas on a factory propeller trailer.

Belly Scoops, Dog Houses, Radiator Seal Frames & Induction Trunks
All of the above items have been restored for some time now, and this past week they were taken out of storage and test fit. The fitting went really well with a very minor amount of trimming and alignment.

Test fitting of the induction trunks

Guns & Ammo
I spoke to the machine shop completing our .50 caliber replica guns. He assured me they would be completed sometime mid-November. 

A machine gun buyer/seller contacted me and told me he would be bringing us all the loaded ammunition, heads and primers (less powder), sometime in December or January. 

Cowlings – FWF
Three of our team members have started to fit the cowling skins on all of the completed cowl ribs that they finished prior to our get together. We are having some fitting difficulties with the new cowl skins that we had made four years ago. But with some additional English wheeling (a special roller machine to form compound curved skins), they should fit well.

Right-hand forward windshield close-out panel installed

Newly formed engine cowling interior ribs

Newly formed engine cowl Dzus rails

The Fuel Control box and 90% of the wiring is now
installed and hooked up in the left-hand cockpit

Newly machined main landing gear door hinge retract forgings

The Katz
Allison is going to be getting a companion pretty soon. One of the stray cats that Suzzie has rescued and nurtured, will be coming to live at the hangar. I can hear the howls now between Allison and the new one until they finally calm down and get along.

“You are bringing me what as a companion!!”  

Our XP is really starting to take shape and look like an airplane now. Our shipping containers are becoming more and more empty every day with all of the completed parts being installed on both fuselages.  

Tom’s appearance on Warbird Radio 
I had a very nice interview with Matt Jolley of Warbird Radio this past week. I could not believe how many people tuned in to listen. The responses on our e-mail and Facebook page have been overwhelming. 


Saturday, October 3, 2015

September XP-82 Twin Mustang Restoration Upd

September was a very exciting month for our XP-82!

The final skinning and completion of the lower part of both outboard wings has now been completed. The sheet metal team is doing the final fitting and riveting of the last outboard wing bulkhead. This outboard bulkhead holds the structural 10/32 nut plates that the wing tip attaches to. The drop-down pitot mast (airspeed indicator) has been fit and completed, and it is at the cad plate shop, expected back any day now. 

The sewing of the fabric gap-seal canvas is being completed. These fabric gap-seals create a barrier so that the airflow over and under the wings will not be able to transition through the gap between the aileron and the trailing edge of each wing.

Take notice of the rivet bucker inside the fuel cell area

Fuel Tanks/Fuel Systems
Now that the wing skinning has been completed, the four outboard tanks can now be permanently installed. The fuel capacity is 205 gallons total for each outboard wing, and 95- gallon tank in each side of the center section, giving a total fuel capacity of 600 U.S. gallons.  

All of the fuel feed and fuel vent lines, along with the cross-feed check valves, are now permanently installed along with the electrical conduits and internal wiring that run through or near the fuel tank bays, i.e. boost pumps (four) and liquidometers (six). 

The electrical team has been hooking up all of the electrical connections in both cockpits. They are about two-weeks away from completion, and at that time, we can put power on the ship and final check each system.

When the electrical system is final checked and accepted, the completed instrument panels with all OHC instruments will be installed (OHC – overhauled condition).

Pilot's side electrical shelf partially completed with the 
temporary tie wraps prior to lacing cord

The fuel control box, which controls everything to do with fuel, i.e., boost pumps, fuel gauges, fuel shut-offs/cross-feed valves and drop tank(s), is now electrically bench checked and completed and ready to be installed. This will be accomplished when the final testing of all the other circuits has been proven. 

The left-hand engine is now permanently installed, with the right-hand engine being installed next week, and all of the overhauled accessories will be installed in their respective positions on each engine, i.e., generators, governors, tach generators, fuel and vacuum pumps. Both overhauled engines came from Vintage V12s with the overhauled carburetors mounted.

This is the right-hand turner

Engine Cowlings
The sheet metal crew has started duplicating the ribs for a pair of right-hand upper and lower engine cowlings. 

Newly machined radiator coolant neck identical to the original cast one

Newly machined aft up-lock latch hooks and trunnions for
the main landing gear doors

"I'm hiding. Don't tell Tom 'cause he will put me back to work." -- Allison

We apologize for being three days late. We have been busy wiring and hanging an engine.


Tuesday, September 1, 2015

August XP-82 Twin Mustang Restoration Project Update

Another great month on our restoration of this magnificent and rare warbird

Fuel Cells and Liners
We finally have completed the fuel cell test fittings. Quite a bit of time was spent positioning all the fuel scuppers (overboard fuel drains), fuel necks, fuel caps, and liquidometers in the openings on the outboard wings and center section. All of the fuel vent lines were completed by the end of July and we had to temporarily install the fuel tanks, and liners in each of the six positions to confirm that the tanks lined up exactly with each fuel filler, feed and vent line.  

205 gallons total in the RH wing fuel tanks

LH 95 gallon center section tank
(600 US gallons total in our aircraft)

Fuel scupper

One of the more complicated fuel vent jobs was the manufacture of the inverted fuel vent plenum with the back-flow check ball assembly. We copied the original corroded one as exactly as possible.

All the final fuel bladder installations should be completed by the end of October. We must have put in about three months of solid work to get all of the fuel system fitting perfectly.

Outboard Flaps
Both outboard flaps will be completed at the end of next week.  They were a relatively simple build with no hidden “gotchas.” The original top skins on the outboard flaps were .025 aluminum. When the NACA test pilots walked off the trailing edge of the wing, their footprints dented the upper skins (even though it says “NO STEP”). We chose to increase the thickness of the upper skin to .040 to cure this footprint denting problem in case any future  pilot exited the aircraft off the back of the outboard wing.

Final riveting the left-hand outboard flap

Completed right-hand outboard flap

Outboard Wings
Now that the outboard flaps and the fuel cells have been final fit, the completion of the lower wing skinning can commence. The lower skins on the wings were intentionally left off to gain access for the final fuel tank alignment and fitting. The lower skinning of both outboard wings should be completed by the end of September.

The final hookups of all of the primary and secondary electrical wiring will start on 1 September. 

Most all of the fuselage wiring has been final terminated to all of the terminal strips located on the shelves forward of the instrument panel(s). All of the numbered and labeled wiring harnesses from the center section, wheel wells and outboard wings have been pulled to the shelf locations, awaiting to be hooked up to the terminal strips. 

We expect to have the majority of the electrical system(s) completed within a month. 

All twelve Merlin engine-mounting Dynafocals and attaching horseshoes and plates have been completed and delivered. These have been one of the more difficult machining tasks to complete. It would have been simple if we could have just bought twelve P-51 mounts, but they were slightly different in outside dimension and lengths. 

Four horseshoe mounts on the left.
Mounting plates on the right.
(assembled with temporary hardware)

On 1 October the two Merlins will come out of their nitrogen-filled cans and be permanently installed on each mount. 

Both disassembled propellers will be trailered to Germany’s  MT Propeller stateside facility located in DeLand, FL. They will assemble both props and call us when they are both completed to return back to us.

One of the two mounted rotating beacons that Larry Kelley, B-25 "Panchito",
contributed to our project.

Installing scupper drain lines in the center section fuel bays
(When hired on, did he know he was signing up for THIS?)

"Whatcha doin' up there?"
--- Allison


Saturday, August 1, 2015

July XP-82 Twin Mustang Restoration Project Update

Minor Change of Priorities
We were planning on completing the wiring in the cockpit starting this July. After witnessing the rapid progress the wing sheet metal crew had made on both wings, we realized we had to complete the fuel tank liners and all the fuel vent tubes so as not to hold them up on completing the skinning of the aft bottom of both wings.

These lower wing skins had to be left off for access to complete the fuel liners and vent tubes. Both are now completed, and the wing crew has started on the lower skinning and flap bays.

Four large boxes of foam filler panels for our fuel cells

Fuel bladder (tanks) close-out panels with the liquidometer (fuel level sender)
and fuel neck and cap

Wing Trailing Edges

All wing trailing edges and aileron hinge points are now completed and permanently riveted.

Outboard Wing Flaps

The sheet metal crew has now started on manufacturing from scratch both outboard flaps. We had both original flaps from the Alaska wreck site, but not one piece on either flap was usable for rebuild, only as patterns.

Fuselage Internal Fuel Vent Lines
The bending and installation of the multitude of fuel vent lines in the area behind of the aft cockpit wall(s) and forward of the radiator(s) is now completed. Each of these fuselage fuel vent line assemblies have large vertical and horizontal loops designed in them to prevent a discharge (loss) of fuel during inverted flight maneuvers. This fitting and installation of these tubes was difficult and time consuming, but both fuselages are now completed.

Mandrel-formed fuel vent tubes

Installed fuel vent lines

One left and one right combination generator/spark plug
blast (cold air cooling) tubes

Fuel Feed Lines
All of the special mandrel-formed fuel feed lines from the tanks to the center section check valves and continuing forward to the fuel shut-offs are now completed and installed.

Left-hand fuel feed lines and check valve installed

Right-hand fuel feed lines and check valve installed

The crew is now completing the last minute to-do July items and when finished, they will start on completing the final wiring hookups in the firewall/cockpit/instrument shelf areas in both cockpits. This will start sometime in mid August.

Engine Installations
The special rubber engine Dynafocal mounts that are being manufactured for us are nearing completion. When these are done, both engines will come out of their sealed cans and be installed. We are looking at late August or September at the earliest for this to be completed.

Both radiators are now permanently installed. The final fitting of the four radiator coolant tubes in each side must wait until the final small-to-do tasks in each bay forward of each radiator is completed. If these tubes were installed now, there would be no human access to these two bays.

Left-hand radiator pictured, right-hand radiator in background

Newly machined tail wheel gear door hinges

Carburetor mixture linear actuators
(fuel mixture on/off)

These were the last two firewall forward parts we were having an extremely difficult time finding. Larry Kelley, B-25 "Panchito", found two NOS ones for us and contributed them to our XP project.  Thanks, Larry!