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  1. DT fyoffs – get highest
  2. DT fly-off – we have the regs and we should use them.
  3. Clipping the wings is the answer
  4. Cheap Tracking

DT fyoffs – get highest
From:Tapio Linkosalo
In my opinion, there is one very major problem in “DT flyoffs”: the sinking speed of the model DT’ing. Judging different models, the DT speed varies a great deal, and at least for gliders, the DT speed can be changed a lot by adjusting the tailplane angle. So the overall flight-time to ground after DT will depend a lot on the DT characteristics of the model. Shall we next trim out models to lose altitude on DT as slowly as possible? Hopefully not.

This winter we tried another option in F1H competition in Finland. We flew the flyoff to 4 minutes maximum, but before the fly-off decided, that if there are maxes, then the highest DT altitude wins. It happened that we had to maxes, so the altitude at DT was the decider. The concept seemed to be functional.

Of course even this approach does not come without potential problems. In this case the problem is the accuracy of the altitude loggers. The loggers are not calibrated, and the measurements are prone to temperature bias: the equation that converts pressure changes to altitude depends on ambient air temperature, but this feature is often not taken into account in the logger output. However, for gliders there would be an easy means of calibration: observe the model altitude on tow, and refer the DT altitude to that.

So this is my suggestion for DT fly-off: fly the round to a sufficiently long flight time. 2 or 3 minutes flight should fit in the field, if ordinary rounds have been flown. Equip the models with altitude loggers, and decide the contest result on the DT altitude (not time to the ground). Highest DT altitude wins!

DT fly-off – we have the regs and we should use them.
From: ron kreetz

DT fly-off.
I agree with Frederick. We have our regulations and we should use them.
In the Netherlands, with small fields we practiced often DT fly-off. We do
it only for the day prize, for selection points or Nat. Champs rating we
share the points. IMO it also could be used international, when necessary
ico small fields or wind conditions, for the day prize. Not for the WC
points etc. ‘Dirty minds’ could build a model just for slow sinking rate…
Ron Kreetz

Clipping the wings is the answer
From: Steve Helmick

Replying to John Carter’s email. As I proposed 3 decades ago and several times since, I believe the best solution to model “over performance” is to have wingspan limits. It is done in some other events, such as 2-meter R/C glider.  I suggested returning to spans something like the typical models of the 1970’s, with 2 meter span for F1A, something around 1.5 meters for F1B, and 1.6 meters for F1C.

This would obviously reduce climb and glide performance, but would do multiple other good things. It would mean that you could use a simple VIT to get an excellent transition to the glide, making the bunt unnecessary. It would probably make the folders obsolete. One of the things that should appeal to most is that it would make a traditional DIY balsa & spruce model be potentially competitive at WC level, meaning that costs would or could be reduced a lot, AND make it possible for an enthusiast from anywhere on Earth to build a competitive model. What could be better than that? Thermals for all, Steve O’Bat .

Cheap Tracking
 From: Mike Richardson

Hello Roger

A year or two ago at Lost Hills I helped a friend track down a model who had borrowed a Chinese knock off (red in color?) of a Kenwood. I seem to recall it was yours and the price was extremely responsible.

The reason I ask is I have several AMA gas flyers here in Vegas who looking for a inexpensive tracking system. Transmitters are not a problem, Merlin have some excellent ones for $95. As for the Kenwood, that’s a different story. That’s when I remembered the generic one you had. Might I ask where you came up with it? I’ve searched the net but with little success.

Regards,
Mike R.

Editor’s Note:  I decided to reply to Mike’s personal email on SEN because it maybe of general interest.
Just Google Baofeng or look for it on Amazon and you will find much low price radio technology.  Compared with the popular Kenwood model you get about 90% of the capability at 10% of the cost and now the popular Kenwood model TH-6 (from memory) has been discontinued and it’s replacement which has a bunch of digital features that are of no use costs about $100 more.

BTW there are other well known makes that do have hand held dual, tri and quad devices that work well and are priced between the Baofeng and the Kenwood

In addition to the low cost $30-40 some Baofeng radios come in colors so are easier to find on the field.  The one I  lent was a red one.

The downsides other than a slightly reduced performance is that they do not have the LSB/USB/CW facility the Kenwood does to convert breaking the squelch noise into  beep, they receive on a smaller number of frequencies and there are a confusing number of models from many suppliers all of whom claim to be the real deal.
If you have Walston Rxs there are some Baofeng models eg the UV-x5x range that will cover 220-227 mhz that later model Walstons use.  Virtually all will receive on 130-170 mhz.

Like the Kenwood there are a number of after market antenna from very short to longer with better range. Make sure you get one with the right connector for your radio.   In the USA Arrow Antennas make hand held Yagi antenna (out of arrows of course) to suit any frequency range we might use.