ALMOST READY TO FLY
I thought club members new and old would be interested to read of my experiences with A R.T.F. A brief history of my model building began 35 years ago with free flight gliders and control line, both built from kits. then followed several years boating sailing, scale and power mostly built from plans. During this time I acquired two daughters and a very understanding wife. (Not in that order I hope Chris!) I joined P.A.R.C.S. 2 years ago and after a short time flying power I returned to gliders only this time with radio. I started with a Goldberg Sophisticated Lady followed by a Flair Sunrise and after reading reviews in the model magazines, I ordered an OPTIMA 100. Some months later I collected a large box containing all the parts needed to construct my glider ready finished, along with a small hardware pack and an instruction sheet. The quality of the covering was very good and in taking my time with the assembly and installation of the radio gear I was very pleased with the end product. Being a novice flyer I had enlisted the help of our instructor Ken Tinkler, who had been previously teaching me whilst I had been trying to wreck my other two gliders. With the encouragement from Ken and help from Jeff, Mac and Mike, my gliding slowly improved.
At the embankment for an afternoons flying one weekend, Ken found after several flights for the postal comp., that the rudder horn of his glider was broken. He had flown my Optima before, so I offered it to him to complete the postal comp. Whilst launching the glider for him on the bungee I accidentally turned off the receiver. The result being a javelin like landing from some height, despite Kens frantic knob twiddling. A another lesson had been learnt in the positioning of the radio switch and the direction of the on/off . After digging the fuz from the ground the only damage seemed to be to the nose of the fuz., wings etc. were all O.K. I returned to the workshop to inspect the damage more closely. The basic construction of the fuz, is traditional spruce longerons and sheet balsa sides, top and bottom. A substantial bulkhead locates the wing which is bolted at the trailing edge to the fuz. The nose of the glider is made up of a ply keel that locates through the bulkhead and some way into the fuz., onto which a fibre-glass cone is attached. I needed nearly 14 oz. of lead to get the C of G, right. All this plus the radio gear being mounted on the keel. The heavy landing had caused the keel to crack at its attachment to the bulkhead, but after use of epoxy and spruce, it was ready to fly again.
Some weeks passed, and my flying slowly improved. But as members will know when learning, landings can sometimes turn into arrivals. One weekend after several particularly hard landings the nose cone/keel broke again. This time using the keel as a template I cut out a new one only this keel was made from 3/8 ply. After removing the old and fitting the new I was once more ready to fly. Needless to say this repair lasted just as long as the original, so once more it was back to the workbench for much head scratching. What was needed was a more permanent repair. The modification I eventually decided to attempt involved cutting a hatch out of the fibre-glass nose cone and grafting it to the fuz. But this time sandwiching a two inch balsa box between and so reducing the amount of lead required to balance at the C of G. The hatch was cut from the nose cone, the nose cone reinforced as was the bulkheads and longerons, and glued to the balsa box that had been previously constructed and shaped. The repaired area was spray painted, the glider re-balanced and on a calm day a hand launch tried. All went very well, several bungee launches followed and after trimming my Optima 100 flew. I am sure better than before. Some weeks passed and my confidence in flying was improving but landings were still a tense affair and I was happy to land in the field even if it meant a long walk.
One blustery day when coming in on finals, I did not maintain enough flying speed. In consequence it stalled, and being too low for recovery the glider landed wing first. Not at all how it should be done. Another lesson learnt, donít let the nose come up when tying to land. Unfortunately the glider had come to rest close to some of the horses tethered on the field, and the sudden arrival of my glider caused them to run in circles, dragging their chain with them. After retrieving the bits it was back home to inspect the damage. My wife had by this time, got used to me arriving home with more glider parts than I had taken, but it didnít stop her commenting on the lack of time spent gardening or decorating. It looked OK but on removing the covering from the center wing a lot of pieces fell out. The tail plane looked good, the rudder and fin were broken and the top section of the fuz., needed to be replaced. It appeared to be a lot of work. The fuz., top section was replaced, glued in place with bolts for securing wing and tail-plane inserted after careful measurement. A new rudder was hinged to the fin, profiles taken from the broken parts, glued in place and covered in film. My repair to the wing after some thought, was to differ from the original in two ways.
Due to the large size of the tail-plane I decided to increase the wing span by twenty inches and to improve itís strength sheeted the top and bottom back to the spar D box which had been lacking on the original model. Ply templates were made for ribs to be made by sandwiching and sanding, spruce spars, alloy tubes for tips and a ply plate for attaching to fuz. All the parts when glued and covered were once more assembled and balanced. Again hand launches were good and after several bungee launches trims adjusted and my OPTIMA 100 PLUS was flying well.My flying was slowly improving but due to family commitments, work and the weather it seemed to take a long time. Some months passed, I was still flying the Optima, without having to keep repairing it, I had managed to build another glider. My flying times had got longer and now and again I actually found myself in a thermal, this was getting more enjoyable.
In the meantime Ken, and other club members, had been constructing an electric winch, others were looking for more height at launch, for myself, a reasonable launch on calm days would be enough. At the field one weekend with very little wind a launch on the winch was tried with fears of a of the unknown. The launch tracked straight just like on the bungee with little bend in the wings but my inexperience in pinging from the winch resulted in the wings clapping their hands!!. More bits of glider to take home and repair. At the field the damage didnít look too bad, but on closer inspection at home as well as the wing to repair, the elevator and rudder hinges had pulled out of the fin and tail-plane, causing damage to both. The fin, even though it had fallen vertically from great height, only had cosmetic damage. The servo rails had broken. My earlier modifications to the nose area had withstood the unorthodox landing. I was pleased.
A new wing center section was constructed along the same lines as before, this time I added some carbon spars and fully sheeted the middle. I also made up a wide triangle of ply to take the stress away from the wing bolts. The covering from the remaining flying surfaces was removed and the bare parts examined. The wing tips were in good condition, the tail-plane needed rebuilding and the fin trailing edge repairing. All work proceeded well and after sanding and covering, both fuz and wing, installation of radio gear and balancing, it was once more ready to fly. My Optima 100 plus is waiting for a test flight, but as I write this we are experiencing rain and gales but by the time club members read this I hope it will have flown. It just goes to show members must be prepared to bounce back as much as their gliders. I am grateful to all club members for their help and advice.