National Free Flight Society

SEN 2292


  1. ADT for all !
  2. Keep 20
  3. Scrap 20
  4. Reminder


ADT for all !
Captain SCAT,
I think Tmat is conflating a number of different arguments in SEN 2291; let’s split them up.

Safety: Yes, there is a very good argument for making RCDT mandatory for all FAI classes for exactly the reasons he describes. I suspect that an F1C stuck in bunt on power would probably always break the joiner so there is a question over whether that situation is more safe than not DT’ing – but we have that rule in place anyway. For F1A the model does tend survive such punishment and yes, the speeds they can now crash at leads to a potential safety issue. So RCDT for all is a no-brainer (yes, F1B’s can crash and hurt people as well).

ADT (Automated DT): If there really is a system in M&K timers that allows this to happen then that would be great. Can Captain SCAT, Lord Favionics and others tell us if it is possible to have a small, light (cheap ?) interface between the RCDT and timer (or timer and servo) to allow us all to have this safety feature ? If so we should perhaps make this mandatory as well as, if Tmat is correct, if current RCDT methods can still result in the death of Canadians then that is a bad thing.

The Problem: If ADT is mandatory for safety reason then it is a closed-loop function that isn’t allowed in the rules and hence must be banned. We must assume that if the system is in place that it will be used for more than just trimming by some with fewer scruples than others in order to gain an advantage under the 20s rule (maybe that’s happened already …).

The question we need to ask at this point is if performance over safety is the right approach?

The Solution: Kill the 20s rule, it’s a bonkers rule, very anachronistic and useful in the era of RoG and no other. We should not reward failure as in other lower-grade sorts like tennis, so kill it, kill it now.

Further, make RCDT mandatory for all classes and hence allow and encourage ADT. This will make the sport safer (good thing), will reduce numbers slightly in FOs (good thing), will not make any current models obsolete (good thing), but no doubt some people will still flounce off – no change there then.

Perhaps we could have another of those polls to gauge the view of the masses ?


Editor’s comment :  EoB, I believe that Favionics also has what you are calling an ADT.  Also some work in being done on that at the Magic factory.  While you could make an add-on device I believe that close integration between the timer and altimeter is required. Also not all altimeter sensors would be suitable as to do this well some accurate real-time processing of the altitude data is required that may not be needed in a traditional attitude plotting application.

Keep 20
From:Stepan Stefanchuk

SEN 2291
Please leave the rule “20 seconds ” alone!
Please keep the 20 second attempt rule.
It should be kept.

Scrap 20
From:john carter

The 20s Rule
This is a left over from ROG days and penalises those, that say land in a tree 20 m up at 2.50 and did nothing wrong (it is free flight ) but the guy who really messes up and crashes of simply does a sub 20 then goes on to win on the re fly.
As far as safety is concerned we can all site many scenarios to any situation.

Reminder CIAM Meeting Coming up Soon
Recently there has been discussion about some items e,g, 20 seconds  on the  agenda of the upcoming CIAM Meeting.  There are two comments that we would like to make about that.
The first is to make sure that your National Aero Clubs (or whoever is representing them at the CIAM ) knows how you feel because they are the people who vote at the CIAM.

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Roger Morrell