VQ Models P-51B - A Used Airframe Rebuild

Amaadur Rahman, a fellow RC Pilot from SNHFE in Merrimack called me a few weeks ago and told me he had been given a VQ Models P-51B Mustang airframe that was in good condition (the wings actually measure 61 inches). It was too big for him to transport, and he thought I would enjoy repairing and setting her up, so he gave it to me! Thanks, Amaadur!

It is in pretty good condition. I am going over it carefully and am trying to keep my costs down. I have on hand a Hobbywing 100A ESC, and a HeadsUpRC 5065-04 1400 watt motor (at VQ Models estimated 7 lbs AUW, thats 200W per pound. My other choice was a 700W motor, and ain't nobody got time for 100W per lb. But that max watts is likely on a 8S battery, and I am flying it 5S, so it will be interesting to see how many watts it ends up drawing). I also have an Orange RX 3 axis stabilized receiver, brand new.

I want all metal gear, digital servos, so today I ordered 4 Corona DS329HV Digital Metal Gear Servos, and a Turnigy 5A 6V SBEC. I have 4 5S 4500 mAh batteries that may need replacing, and one 6S that likely does need replacing, and they fit. Someday I will, but once I know what she likes. I am also replacing those ugly fixed gear for retractables. I have the same servoless retracts I used on the Spitfire, and today ordered a set of struts that are for the Spitfire as this about the same size, from Tower Hobbies. They are updated from the ones that came on my Spitfire and are rather cool looking.

Today I started on the fixin' up.

The model is in pretty good shape. I can't match the stock cote, so I decided that I will put D-Day stripes on that right wing.

Its a sign that the pilot came loose, and I had to re-install him. The canopy came off easily and he's now sitting proud.

I wanted a bigger tail wheel, so I swapped it out.

The cover was on wrong and wasn't flush, so I fixed that. The tail wheel was loose on the turn thingy, so I changed out the set screw for a screw-screw and snugged it up as best I could. Leaving the weights on for now.

I rebuilt the cover and the doors and coted it. Snazzy.

Curiously there is no vent. Electric aircraft, especially one with a huge motor and ESC need a lot of airflow and most have an aft vent to allow flow-thru of cooling air. So I decided I would cut a vent hole and use a vent cover from an Eflite Pulse 25XT that I painted. Marked out the opening.

Opening made. There is nice continuous airflow, but I will make an opening in the cowl under the prop.

Epoxied for strong hold.

Vented.

The wing-fuselage cover is broken and I wasn't sure how to fix it...

I decided to use foam and wood filler.

Trimmed a piece of painters tape to mark the curve.

This is the dense wood filler I am using. I don't want to fill the entire space with it, so trimmed some foam...

And stuck it in the hole.

Then filled it with wood filler. A few hours later I light sanded it, and this weekend I will finish it. I am hoping the silver paint I have is a fair match. Its a warbird, it doesn't have to match. Not sure if it won't fall off as it won't flex well.

I installed the motor. Pretty much fit the stock holes.

I epoxied the battery tray (behind the clamps) as it was loose, and made a small cross piece to mount the receiver, here being epoxied under the clamps.

That's pretty much it for today. This weekend I will finish off that wing cover and make the vent opening in the cowl then install it. I will start repairs on the wing cote and put those invasion stripes on the top, and install the retracts, and when the struts come in those too. Same with the servos, the SBEC, and the receiver. They should all be here in the next couple of weeks! I think she is going to be a great flier.