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Bowden

My Bowden Trophy exploits

I was at the 2003 Nationals and watched the carnage that took place when the Bowden Trophy was competed for in the howling gale of the day.  I wondered why those stalwarts cast their creations up into the vagaries of the day.  I watched again for a little while in 2004 and the contest looked much more genteel and the thought crossed my mind to have a go in 2005.

Come 2005 and one week before the competition weekend I suddenly got taken by the idea to compete.  What to use for a model?  I had a Majestic Major which is an 88 inch wingspan version of the Junior 60 but removal of the radio control equipment would have been a bit of a bind and certainly the OS 60 Fourstroke up the front was way over the top.  I soon discarded that idea and looked to my bits and bobs for inspiration.

I had a flat bottomed radio foam wing that the wife was in the process of throwing away (she takes things from the garage and puts them on the trailer under our covered way, then moves them alongside the dust bin for a while, then they disappear). I retrieved the wing from beside the dust bin.  I had a radio model kit that my son had bought at one time and had started on, it was a Hi-Boy with a lite-ply fuselage and it looked useable.

I cut the top off the Hi-Boy fuselage to take the flat bottomed wing, cut the foam wing and re-stuck to give some tip dihedral, made a half sheet half built-up tailplane, sheet fin and covered the lot with the remnants of solafilm that I had to hand.  For the motor I took one of my old Frog 249BB's and mounted it on an alloy plate and screwed that to the model.  I fitted a hypodermic syringe body for a fuel tank and I was ready to go.

The finished object 'BITSA'

I finished the model on the Thursday afternoon and when the wind died down a bit in the evening I took Bitsa to my local test trimming field, which incidentaly is more often than not covered with that mythical commodity, long grass.  Test glides, now that was a bit of a joke, the model weighed over three pounds, any how I hurled it as best I could but I was not sure whether it was gliding or not.  When I saw it rise a bit before it dived back down again I gave it best before I bent something, thank heavens for the mythical commodity.  It would have to wait for Friday.

I waited until late afternoon on the Friday, hoping the wind would die down and off to Warwick race course to try power flights.  I had fitted an engine timer so I had control over the engine run.  Two attempts, two monumental power stalls with resultant nose dives.  Minor repairs to the cabin front and some rudder turn and finally the model climbed away.  Still not sure of glide but it was getting late so I packed up.  Taking the model apart to put back in the car I noticed that the power stall crashes had bent a considerable amout of downthrust into the engine mounting plate so effectively the model had trimmed itself despite my efforts.  Back home, re-designed cabin front, secured packing, Nationals Ho!

The day of competition arrived, I had failed in the SLOP comp in the morning so I was able to devote some more time trimming Bitsa.  Quick test flight on low power, looked OK but not high enough to see glide.  More power, a bit higher but still not sure of glide but on landing the rough ground tore off the undercart so after emergency cyno repairs and a bit of packing under the leading edge of the tail I moved off to the flight line.

The Bowden comprises two flights, best one to count.  You must start within one minute, take off and achieve a flight time between 30 seconds and 60 seconds.  There are penalty points for flight time deviations about 45 seconds and other points about which I know nothing.  I fires up the engine for the first flight and away goes Bitsa, two ground loops, no takeoff and I run out of time, no flight.

I try a test flight between rounds and with the tail packing removed Bitsa takes off climbing more like a duration job than a sports model.  The engine run was quite long and although I was pleased to see the model gliding it went as straight as a die and finished up way off the airfield about half a mile away in a new crop field.  I  recovered it and only just got back in time for my second flight.

I cut half the turn packing off the fin fired up Bitsa and she took off, frightening a photographer as he got chased across the runway.  Still no glide turn but Bitsa landed just inside 60 seconds and just in the airfield, I had recorded a qualifying flight.  I finished up 20th out of about 50 entries so I gave myself a pat on the back.

I was there and I flew the Bowden.