Puma (oz15673)

About this Plan

Puma. Radio control sailplane model. Wingspan 40 in, for 2 channels.

Quote: "One day back in 1977, I was staying in one of the hotels at London's Heathrow on stop over. I was working as a flight engineer for Gulf Air on VC 10 aircraft. At about 6 am the phone rang and the operator said that call time was delayed indefinitely. Eventually we were stood down and told that we were not leaving until Saturday - five days hence.

It was winter and the weather was atrocious.The thought of staying in a five star hotel on company allowances, plus £3 a night, with nothing to do except eat and drink and party with the girls filled me with horror - honest!

Anyway, I went to Hounslow and paid a visit to Radio Control Supplies, (hiya Ken) and bought a Chris Foss Middle Phase kit to build in my room. I managed to finish and cover the fuselage and tail bits and put the wood on the wings. All this between parties and meetings at the Ostrich and Three Magpies! And that's as far as it got.

There being no hills in Bahrain from which to fly the model, it stayed in the box until 1995 when I took it out with the idea of finishing it for our Manx Festival of Model Flight week.

After all those years the Solarfilm finish was like glass still, both on the fuselage and the tailplane.The Obechi veneer on the wings though were another story, and had lifted badly - not surprising though was it!? Being a real pack rat I put the lot away again for another year and then took it out again for our '96 bash.

I forgot to get new wings, but later I noticed that the last twenty inches, or so, of each wing seemed OK. Cut down they would be suitable for a small sloper and so some drawings were done and the first model built. It has been flying now for 2 years with only a few minor repairs and modifications.

The model is not suitable for a first time sloper, but I'm sure that most will manage it if it is their second or third aileron model. You'll find that it is a handy size to keep in the car ready made up and waiting to go.

Due to the small size mini servos must be used and a small battery, 250 to 400mAh size.The receiver will have to be pretty small to and I use one of the Micron units which are very reasonable in price and have given me excellent service.

Wings: Okay then, write to Chris Foss and get him to send you a pair of Middle Phase wing panels. When they arrive cut off the outboard twenty inches of each and join them together. Only kidding... get a pair of wings made up or make them yourself - it's so easy. Glue on the LE, false TE, and wing tips. Sand everything to shape and give the whole wing a final burst with a very fine wet-and-dry. Use TE stock for each aileron and add the ply reinforcing for the horns. Top hinge the ailerons using Solarfilm strips. Carefully trim the root of the panels so that when the tips are blocked up at the correct dihedral angle, they fit properly prior to gluing together.

On a small wing like this I don't use glass cloth and resin to reinforce the wing joint, instead I paint the area with PVA glue diluted with about 10% water. Let this dry and then use an old, but not rotten, piece of sheet or pillow-case and paint this on using full strength PVA.This may require a full 24 hours to dry, so if you are in a hurry, use the more normal glass cloth method.

Now that you are nearly in the finishing straight give the whole kit and caboodle a good sanding down.

Fuselage: Cut both sides from 1/8 ply and mark the insides of each piece. Glue on the 1/8 square longerons and mark the former positions.To one side glue formers F2 and F3, the servo tray ready cut-out to fit your servos and the wing bolt plate. When everything is firmly glued in position, glue the other side to the formers and servo tray making sure that it is properly aligned..."

Puma from Silent Flight, March 1999.

Direct submission to Outerzone.

Supplementary file notes

Article.

Corrections?

Did we get something wrong with these details about this plan (especially the datafile)? That happens sometimes. You can help us fix it.
Add a correction