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- Category: Archive 2012
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- USA Team selection flash
- F1Q EL
- Q-uestion from Klaus
USA Team Selection Flash
Day 1 F1A and F1B
F1A - team place 1 not decided - flyoff tomorrow morning between Jim Parker and Mike McKeever
F1B team place 1 decided Alex Andriukov
F1A 5 in Flyoff
Limberger
Spence
Parker
McKeever
Van Nest
Rene Limberger's LDA gets way highest but does not make 5 minutes
7 minute round
Parker and McKeever make 7 minutes
Brian Van Nest about 6 and half
Steve Spence fourth
F1B 6 in Flyoff
Andriukov
Batiuk
Simon
Booth
Shailor
Tymchek
Simon and Shailor drop
In 7 minute round
Andriukov make 7 minutes easily
Batiuk over 5 and half
then Bill Booth
and Bob Tymchek
Very nice weather
Most drama in F1B. In one round a dust devil make Bill Shailor's airplane do a 180 into the ground for an attempt and flips both Batiuk and Ghio at atiltude, both recover and make it.
Very tough round 7, dead air and broomstick thermals. 4 top sportsmen clean until that point drop. Andriukov winds 2 models , waits until 1 min left in the round to launch. Has a problem with hub or prop on one model. Switches to second model with 30 seconds left, cranks on a few hand turns, launches. and makes it. Fantastic clutch performance by top sportsman.
F1Q Energy Limits
The BMFA and Aram proposals for the measurement of energy for those wishing to fly F1Q without an energy limiter are good starting points in the attempt to level the playing field. At 10 secs into the motor run (BMFA proposal) or at the mid-point (Aram’s suggestion), the rate of energy usage is comparatively constant for the power train configurations typically used by those of us that fly the simpler F1Q models and it is a far better approximation of the average power being used throughout the motor run than if the initial inrush power is used. However, both fail to allow for one very important aspect - that is the unloading in the air with the subsequent reduction in the rate of use of energy. An energy limiter is a real time device which calculates the amount of energy consumed as it is consumed so if it gets used up more slowly (as indeed it will when climbing as opposed to being constrained on the ground) then the energy limiter will allow the motor to run for longer. There is little data available to quantify this change in the rate of energy consumption when in the air – the only thing I’ve read was on the NFFS Forum and told of a model which was getting a 12 second run when being tested on the ground but was actually climbing for 15 seconds. I believe that both of these runs were terminated by the same energy limiter, which was set to the 5 Joules/g limit. For this reason I would suggest that measuring power at points in the middle of the run rather than the inrush power will fail to fully compensate for the increased run time enjoyed by the F1Q flyer who decides to use an on-board energy limiter. The timed motor run approach makes no allowance for the unloading effect and my own recommendation would be that the energy allowance is increased to at least 6 Joules/g for models not fitted with an energy limiter – this would be in addition to the slipping of the point at which power is measured to 10 secs or mid-run.
Tony Shepherd
Q-uestion from Klaus
Am I missing something, or does John Oldenkamp ???
The old FAI rule specified a max battery weight of 90g. This led to planes sucking them dry in 5 to 7s and definitely outclimbing F1C's. So an Energy limit was set in the newer rule of 5 Joule/g. No mention of battery weight?
So why increase the battery to 120g and NOT set an energy limit? Of course, this would allow these planes to have a motor run of 15s (not possible with the 90g LiPo), and really climb out of sight (which - of course - would end the timing ;) ).
The only change really necessary to the current FAI rule is a reduction from 5J/g to maybe 3.5J/g, and a better definition on how to measure the non-EL planes. And whatever that method will be - results will never be conclusive. You cannot check the run with the same battery the competitor will use to fly (he will insist on a "full" one), and my set of 6 "identical" LiPo packs shows +/- 20% variations ...
Of course, a still better rule (because it would be controllable) would be a FIXED energy budget regardless of model weight, as this would at least allow a check of the EL even after the flight. All current EL`s settings/readouts could be messed up (accidently, of course) during retrieval.
Regards
Klaus W. Salzer
....................
Roger Morrell