HOW TO IMPROVE YOUR CHANCES OF WINNING
“THE BOWDEN TROPHY”
(Having once been lucky enough to win the Bowden Trophy I was asked to give a talk at a Peterborough MFC meeting to help beginners and non competition flyers enter the event. The following is that talk, complete, except for the heckling and barracking!)
The Objective of the Bowden event To achieve a Rise Off Ground flight of exactly 45 seconds (timed from moment of release).
Then do it again (!) (Flights of under 30 seconds and over 60 seconds are void)
I stress that the following notes are based on my personal experience (otherwise known as mistakes!) and what I have learned from watching and talking with other Bowden flyers.
a) The model can be an Old timer or a new design. It MUST however have a Cabin with proper, clear, forward visibility (or an exposed cockpit with clear windscreen
b) It should be stable model and not show tendencies to ground loop.
c) Choose a fairly ponderous flyer which does not climb rapidly OR “float” on the glide. All sorts of models have won the event but I think a good first model is a Junior 60 or similar
d) No matter how attractive it makes the model look do not be tempted to mount the engine inverted. Inverted engines are prone to flood and that does nothing for your quick starting routine
e) This is NOT a duration competition. We can time the motor run, the unknown bit is the glide.
f) Cover the model in tissue or heat shrink textile. Anything else upsets the judge. This is not a good move as some of the points are down to his subjective judgement!
2) Model Details
a) Ensure the fin is “keyed” in place and its position is repeatable
b) Do NOT use a spinner. If the prop comes lose you will never get it fixed within the 2 minutes.
c) Use a nylon prop that is straight, free from nicks and is in balance
d) Ensure your wing and tailplane are well banded on and cannot move in flight
e) Only use ply packing (balsa compresses and trim is lost).Glue the packing in place to make sure it is not lost on the first round landing.
f) By structure, and choice of covering, get a warp resistant wing.
g) Put your name and address on the fuselage AND wing(s). With your name labels on you have some chance of getting it back if lost. Without them, virtually no chance. Near Barkston there is a lovely man (Walter) who knows all the farmers and he will contact you. He will even work out who you are from your BMFA number!
3) Preparation before the big day
a) Make sure your engine is well run in and will start within a few flicks.
b) Check that the wheels are free running
c) Ensure the model tracks straight and does not veer off to one side. I hold my wheels on with collars. This makes them quickly removable to make adjusting the axle alignment easier.
d) You will need an engine run of around 23 seconds. This can be achieved by using a timer or, by using a graduated transparent tank (this can be amazingly accurate).The former is theoretically more accurate but has more to go wrong (I speak from personal knowledge!). Winners have used both methods.
e) If using an engine timer check its reliability over and over again!
f) Test fly the model in, a variety of weather conditions, from a hand launch.
g) Test its ability to Rise Off Ground (ROG) (don’t push your luck too far, do this on a fairly calm day).The model must not touch a wingtip or “bounce” on take off
h) Try and get a smooth take off, not too much height, a good transition (without stall) from power to glide and a relatively steep, fast glide
4) Read the Rules!
See Pages 27, 28 and 29 of the BMFA Free Flight Rulebook
a) Very obvious, but most important. You will note that you have 2 minutes to start the engine. If you start your engine and release the model but it fails to take off, or makes a flight of less than 5 seconds, you can get a second attempt. SO LONG AS YOU ARE STILL WITHIN THE 2 MINUTES at the moment of release.
b) To paraphrase the rules. You start with 100 points for each flight. One point is then deducted for each second above or below the target of 45secs.
c) Further points are deducted for “falling down” on the following :-
”General design and appearance of the model”/ “Neat building and finish” “Prompt starting” and “Calm handling of model and accessories”
“Long Straight take off run”
“Steady Climb / Smooth transition / Good turn radius”
“Gentle descent / Flares nicely (!) / Not upset by low level turbulence.
Reassuringly, you do not lose points if the model noses over on landing on grass!
The aggregate score for the 2 flights determines your placing. A tie results in a Flyoff
d) Do not give your opponents the chance to lodge an objection to your flight. Put your BMFA number on the upper surface of one wing (the rules say minimum of 19mm high numbers for BMFA comps and min. 25 mm for FAI comps)
5) Your Competition Day!
a) Turn up and pay your entry fee. Very often the running order is the same as the entry times. So, unless you want to be first off, hang back a bit and then you can see other flyers mistakes before it is your turn! Sometimes the first round running order is drawn and the second round is the reverse of the first! Make sure you know what the plan is.
b) Park your car where it will not be hit by competition models (easier said than done).
c) Check where you are in the running order (and put on your wet weather gear?). If there is anything you don’t understand, ask an old hand .They are a great bunch of people devoid of that “must win at all costs”/”why should I help you” attitude
d) Make sure you have a small kit box with you containing spare bands, fuel tubing, prop and spanner, rag etc. It should have room for your fuel squeeze bottle otherwise, on windy days you will spend most of the 2 minutes chasing it down the runway!
e) When the guy two in front of you goes out to fly, get your engine started and keep it warm with short runs every minute or two. Try not to run it close to the flight line as this upsets competitors who cannot hear their own engine! Wrap the motor in a rag to keep it warm (and dry?) between runs. It is usual to mount a graduated tank quite high (half above and half below the spraybar) and, if left for any time with a full tank, gravity may flood the motor ( can you guess how I learned this ?)
f) When called, carry your model to the flight line, greet the judge, tell him your name and model ( you don’t want your flight crediting to someone else), fill the tank, remove the rag, turn the motor over (to ensure it is not flooded) and indicate you are ready for the 2 minutes to start.
g) KEEP CALM. Unless you have flown Team Race or Combat you are probably not used to starting motors to order BUT 2 minutes is a LONG time, believe me
h) With the engine running, get yourself behind the model (this is surprisingly difficult). Don’t Panic- Check there is sufficient fuel, set the timer (or wait until the fuel gets down to the “right “level” for the required run).
i) Check the direction of the wind. There is no reason why we, as a club cannot position one of our members directly upwind of you (preferably with a camera) to give you an aiming point
j) Release the model! Many people point the model to the right of the wind (assuming it is trimmed to go left) as this can stop a left roll on takeoff. Geoff Stubbs says he “points the left wheel at the wind” (on windy days)
k) Remember, the model MUST have three points touching the ground at the moment of release and you MUST NOT push it! (move hands sideways to make this clear).Note! One judge only tells you if, in his opinion, you pushed it IF you make a qualifying flight.
l) Enjoy the flight, watch the model down and get a line on it. Don’t worry about timing it –that’s what you have club mates for!
GOOD LUCK ! Brian Waterland March 2009