by Chuck Cravens
Some very significant events have happened this last month.
Many assume our restoration shop is at the airport but that isn’t the case. It is 8 miles away in an industrial park.
So, along with the usual restoration shop images, we have a section showing the move of the fuselage from the restoration shop out to our hangar at the Bemidji airport on Tuesday, September 13th. The trip on a flat bed was 8.3 miles and took about 30 minutes to complete. It is always fun to watch the faces of other drivers when they see such an unexpected sight as a WWII fighter going by on a flatbed trailer!
A week later the wings arrived from Odegaard Wings, so the time to mate the wings and fuselage couldn’t be too far off.
In fact the reinstallation of the wing was done on Tuesday October 4th, earlier than we expected.
We’ll save those events for later in the update. First we will show some of the fabrication and restoration work that lead up to them.
Mustang coolant header tanks aren’t an easy part to make. They must be made precisely to the original North American drawings and specifications and then be strenuously pressure tested.
The process of stamping an indentation for the crankcase breather clearance into the tank half introduces some distortion. That distortion must be taken out of the tank half before moving on to welding.
Cooling Induction and Exhaust
We’ve seen many pictures of the scoop, doghouse and exit door. That is because an awful lot of work is necessary to complete this complex area on a P-51. The scoop goes on after the wing and fuselage are mated.
Early this month, fabrication and fitting of the final sheet metal skin pieces and finishing the engine systems were the order of the day.
Another job was removing the nickel plating on the prop blades. The supply of P-51 propeller blades is becoming smaller and smaller, so they are difficult to acquire and very expensive. There is an STC ( Supplemental Type Certificate) that allows the use of Grumman Albatross blades on P-51s. Due to the expense and limited availability of P-51 blades, the Red Tail takes advantage of that STC and uses these blades.
One of the more tedious jobs is peeling off the nickel plating on the replacement Grumman Albatross prop blades in preparation for complete overhaul.
This has to be done extremely carefully so as not to damage the blade itself.
Since an Albatross is an amphibian, their prop blades have nickel plating to protect against water erosion. When we use the Albatross blades on a Mustang, we remove the nickel plating. It is a painstaking and long process, but since we aren’t equipped to do it electrochemically, we chip it off by hand.
This is done not only for authenticity, but because the nickel plating can split at the leading edge of the blade. If that happens, all the nickel plating needs to come off anyway. Doing it now may save downtime in the future.
Red Tail Move
As I mentioned in the introduction, an auspicious event happened on Tuesday, September 13th as the Red Tail Mustang left our restoration shop to be moved out to the airport hangar. This signals we are nearing the stage where Tuskegee Airmen will be wearing her wings once again.
She will continue to have work done on the fuselage and tail assemblies as she awaits her wings.
The Red Tail’s Wing Arrives
A week later, on Tuesday September 28th, the wings arrived on another flatbed all the way from Odegaard Wings of Kindred, North Dakota.
B and C models had 4 .50 Caliber Browning M-2 machine guns mounted this way. It caused some feeding issues in heavy maneuvers. The ammo belt had to feed over the top side of the guns and make a sharp turn as it entered the loading port on the side of machine gun’s receiver. The weight of the of the ammo increased with g-forces, resulting in jams and stoppages. In the field this problem was addressed by adding B-26 booster motors to drive the belts.
The real cure came with the 6 gun P-51D and later Mustangs. The guns in those later P-51s were mounted with the sides of the M-2 receivers straight up and down rather than tilted.