Adding a Tow Release to the Hangar 9 Super Decathlon

[JimD]

[JimD]

I had a request from a member that I recreate the build thread I did on the Hangar 9 Super Decathlon. The first thing was to try and get all of the pictures posted. As I have time, I will try and fill in the text describing what those pictures show.

We made fuselage modifications to accommodate the tow release mechanisms. On our first build (I have done two of these models) I removed covering on the bottom of the fuselage to gain access to do the modifications. On the second model, we removed the covering from the top of the fuselage and preferred this method.

On the first model, we located the tow release near the trailing edge of the wings. On the second model, we located the tow release immediately behind the top fuselage window. This more forward location proved to be better when towing larger, heavier models.

The single stock hatch latch the secures the top fuselage window was removed and its location was used for the tow release mechanism. 1/8" aircraft plywood triangles were fashioned to add strength and support to the tow release. Some additional balsa was added around the area to enable better covering adhesion. Adding the covering back to the top of the fuselage is a little tricky, but with a few cuts along the sides and some patience, it goes on and looks good.

The longerons that give the fuselage shape tend to bow easily between the formers, so we used 1/8" sheet balsa to make spreaders that were glued between these longerons to prevent the bowing.

Getting the servo wires routed forward and secured is always a problem in these big airplanes. We used a cardboard tube available from T-n-T Landing Products to route these wires. We made gates attached to the formers to hold this tube.

All of these modifications can be seen in these pictures.

[JimD]

We made changes to the top window frame to strengthen it. Triangle was added all the way around the inside of the frame and two latches, one on each side, were added. These latches lock when pushed rearward and have proven to be very secure and yet make the hatch easy to open.

A plywood servo mount for the tow release servo was attached across the fuselage former under the release mechanism. It attaches with four screws into blind nuts so that it can be removed it allow access for servo maintenance.

These modifications ca be seen in these photos.

[68mustang]

Thanks Jim. This will be great. Ron P