Sunday, November 2, 2014

October XP-82 Twin Mustang Restoration Update

October was a fabulous month for our XP-82 Twin Mustang

Aft Fuselage Extensions/Dorsal Fins
The final microscopic alignments and attachment of the aft fuselage extensions have now been completed along with all of the primary and secondary flight control pulley brackets, many phenolic cable guides and tail wheel attachments. The team is now into fitting the two dorsal fins on the top of the aft fuselages where they flare into the vertical stabilizers. 

Some of the many phenolic cable guides that run through the aft fuselages

Dorsal fins being fitted

Canopies and Windshields
Both canopies are now permanently fit and attached.  The jettison system for the canopies has now been final adjusted so that all three releases on each canopy release simultaneously.  Both windshield frames and glare shields are now trimmed and permanently fit awaiting the four windshield side glasses. A second team is also fitting the fairings that fit underneath the aft section of both canopies. These fairings seal the canopies to the fuselages as the canopies roll forward. 

Aileron Hinges
The fitting of the ailerons to the XP wings is going along smoothly. We had to remanufacture all new aileron hinge fittings on the four ailerons – the XP has four ailerons and the P-51 has two – and all new hinge points that mount on the wings. We also had to machine the new gap seal extrusions that are on the upper and lower skins on the trailing edges of the aileron bays.  Also, both of our outboard flap hinges have been completed and are being located on each wing. 

Outboard flap hinges

Outboard aileron attach points

Both heat exchangers are now completed and have been delivered to us.  Thank you, Martin Radiator. 

The two aileron actuating forks have now also been completed, and the last remaining items we are waiting on for aileron controls are the four cable sectors, two mounted in each wing. The sectors are the control wheels holding the aileron cables that control the up and down movements of the ailerons.

Gun Mounts
All twelve gun mounts are now installed.

The Katz
First of all, The Katz would like to send a special “Thank You” to The Katz Fan Club in Pittsburgh, PA, for sending them a nice box of Temptations treats.  They are their favorite.

 They also had a great time trick-or-treating and hope everyone else did, too!




Wednesday, October 1, 2014

September XP-82 Twin Mustang Restoration Project Update

It has been quite a month!

Tail Sections
For the majority of the past month, most of the crew has been on the final alignment and attachment of the aft fuselage extensions, verticals and horizontal stabilizer. The initial lineup when perfectly, but the microscopic adjustments down to .010 (ten-thousandths - 3 times the thickness of a cellophane  plastic sheet) seemed to have taken forever, but everything is now permanently aligned and attached, and the team has started the final fitting and riveting of the side skins.

Right-hand Aft Fuselage Extension

Left-hand Aft Fuselage Extension

The pulley brackets for all of the primary controls (elevator and rudder), and secondary (trims) are now completed and awaiting final installation along with the four side skins. All four of the elevator and rudder mounting castings and associated matching bellcranks have been final fitted. 

Elevator Push Rods

Right-hand Inboard

Right-hand Outboard

Elevator and Rudder Bellcranks

Both dorsal fins are well on their way to completion. We had to make a few ribs and attachment parts, but the job of alignment and installation of the dorsals went smoothly.

Two other team members have been restoring the multitude of tail wheel gear parts. One cannot believe how many moving parts are in our XP-82’s tail wheels: retraction, extension, steering, oleo, tail door opening and closing, etc. Virtually all the parts needed attention and overhaul to bring them back up to airworthy condition. 

Just some of the tail gear parts

Notice the milling marks on the XP prototype tail gear fitting.

Tail Wheel Oleos

Canopies, Trucks, Opening/Closing Cranks, Windshield Side Glasses
Both hand cranks are now completed and are being installed, and both canopies are ready for installation. All four windshield side glasses are nearing completion. We should have them within a week for routing, trimming and final installation. Even though they look similar to the P-51 series, these canopies and windshield glasses are nowhere close in shape or dimension.    

Canopy Hand Cranks

Outboard Wings
The work on both outboard wings has slowed as we are waiting for the final aileron and flap hinge points for final completion and close-out of the four bottom rear skins.  The remainder of these parts are due here within the next two weeks to coincide with the team completing the riveting of the tail sections. 

Outboard Aileron Hinges

Main Gear Door Opening/Closing Hook Mechanisms
We have received the final forgings for the main inboard gear doors. These parts hold the multitude of push/pull rods that control the positive lock/unlock hooks, which keep the doors securely closed during flight.  They all will be installed this coming month.  Thanks, John, Advanced Manufacturing Concepts.

Inboard Flap Hinges
Both center section flap hinges are now aligned and permanently installed.

Right-hand Inboard Flap Hinge

Coolant Exit Doors,  Header Tanks
Casey Hill, English wheel forming wizard, is due here this week to complete the forming of the two complicated interior coolant exit door skins. Also, both coolant header tanks are now installed, one in each rear fuselage.

Coolant Header Tank

Gun Mounts
The six aluminum gun mounts that will be bolted into the center section are now completed and awaiting installation.  Thanks, Vic, Peres Pattern.

Left: Outboard aileron hinge bearing mounts
Right: Outboard flap push rods

The Katz

"What do you mean you again forgot to get my treats!"
- Allison

Please support the Wounded Warrior Project.


Sunday, August 31, 2014

August XP-82 Twin Mustang Restoration Update

August was an incredible month for accomplishments.

Wings Removed and Fuselages/Center Section Pivoted
This past 15 August the time came to turn the fuselages/center section 90 degrees to the south in our hangar. We used the factory-mounted 45 degree lift points on the inboard side of the center section, right against the fuselage lower longerons. These lift points (¾-16 threaded ports) are designed to bear the entire weight of the aircraft including the engines.  We were able to lift the entire balanced center section with both fuselages and engine mounts with one man lifting and guiding each rear fuselage. The lift and pivot took only about two hours to reposition the aircraft where it would fit out the large south door.

After the lift and pivot, we leveled the aircraft in pitch and roll to within 1/30th of one degree, about the thickness of a piece of cellophane.  We manufactured two vertical steel support pipes to fit into the rear jack points (right forward of the tail wheel attach), and designed them to be vertically adjustable.  At that time we leveled both fuselages on the center section by using the factory shims, and are final-attaching the fuselages to the center section longerons with the remaining six of the twenty internal wrenching NASA bolts. (Longerons are the main beams that are the lower structural rails mounted in the bottom of both fuselages.)

We moved the outboard wing fixture into the hangar and attached the wings to check the washout and made the final microscopic adjustments.

Verticals, Horizontal and Rear Fuselage Extensions
The next day we installed all of trim actuators  in each vertical and the horizontal, (three) and installed all the trim cable pulleys in each vertical. 

We then attached each vertical to its respective side of the horizontal stabilizer. We had to align and hold the verticals in a perfect 90 degree position in relation to the horizontal stabilizer. We used diagonal wires and turnbuckles to make the final tiny adjustments as the verticals are permanently held in place when the aft fuselages are high-shear riveted and bolted to the forward fuselages.

The following Saturday the team built a temporary cushioned wood scaffold and lifted the horizontal/verticals/aft fuselage sections up and forward to within ½ inch of their final attach positions. 

Then came all of the final adjustments to make sure everything was properly aligned prior to drilling and reaming any of the attach holes for the fittings. There were eight exact measurements that had to be aligned:

*  The angle of incidence (the pitch up and down on the horizontal stabilizer in relation to the center section.

*  The alignment of the two vertical stabilizers (toe in, toe out).

*  The exact vertical measurements on the verticals in relation to the horizontal measured between the two top and two bottom rudder hinge points horizontally and diagonally.

*  The exact forward and aft dimension of the center section trailing edge to the leading edge of the horizontal stabilizer.

*  The left and right measurements on the aft fuselage extensions to the forward fuselages. This exact measurement is obtained by shaving the attach fittings of the horizontal stabilizer to the vertical stabilizer.  We intentionally machined all four of them 1/32" thicker to give us extra material if we needed to make small adjustments.

*  The twist of both aft fuselage extensions to align the upper and lower attach points.

*  The vertical attachment of the aft fuselage extensions to the forward fuselage attach points.

*  The alignment of the dorsal fins with the leading edge of the vertical stabilizers.

Everything lined up perfectly.  So then the team started final drilling and reaming all the attachment hardware for the high shear rivets. 

Outboard Wings and Center Section
We completed the riveting of all the top skins while on the fixture, and one more bottom skin on each wing which locked the wings into their final shape.

Both wings are now off the fixture, and the team is completing the final riveting and finishing the fuel cell stand-off angles.

Two of our team members are now fitting and installing the new aileron attach hinge point fittings. One of our machine shops is making the final two outboard flap hinges.

The new inner and center aileron attach hinge point fittings
 are now being installed on both wings.

Two inboard and two outboard ailerons

The final Adel clamping of the wiring harnesses in the center section is now being completed along with the final attachment of the three wiring terminal strips in each wheel well. One of our volunteers is sewing the canvas covers that shield and protect these wiring bundles and terminal strips from dirt and moisture thrown up by the rotating tires on retraction.  Thank you.

The center section nut-plate channels, that attach the fuel tank close-out panels between the outboard wing and center section, are now completed.

Fuel cell stand-off angle installed.

Newly machined forward and aft door lock bell crank
mounts for each main gear door

The new wheels and tires are now installed on the main gear legs

The Katz

"You will not get into this rivet case until I get my treats!"     --- Allison