SEN 1928

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Table of Contents – SEN 1928

  1. Comments On
  2. F1A Changes
  3. Damjan’s Opinion
  4. F1A thoughts
  5. Looking for ?
  6. Watch for ?
  7. Fab Feb Preview

Comments On

We have go some comment of the rules changes ideas that have been floating around. We also added Shlomi’s from FB because he presented an interesting practical perspective.

There have been many more comment on FB and other place thna we can include here. It is clear that a wider discussion is needed.

F1A Changes ?


My opinion about modification of F1A cable:

Personally, I don’t like the proposal of the 1.5mm thick cable and special flag. I am sure that if we go in this direction, we will have a very expensive research to find the lowest drag material cable and flag.
And the control will be extremly difficult.
Honnestly, it is not so difficult to launch very high and the highest are not the more sportive.
They launch high because they spent a lot of time in trimming and it is the spirit of free flight.

Today, we have some beautifull fly off and we still succeed to find a…

I can tell you that I have discussed with many friends and they are all against this proposal.

Best regards


My opinion about the suggestions and ideas.

Damjan Zulic
I wont go in the specifics of F1A category because I’m more of a hobby flier than an professional competitor…
I think that the suggestion for the minimal diameter of the towline of 1.5mm will cause extra problems. Not only to the organizers in the case of measure check but also to the elderly competitors because of heavier towing. Increasing the surface of the flag to 8dm2 and consequently increasing the resistance sounds likeable. But there is a problem because of the bigger flag. The flag or the towline will likely entangle in to the horisontal stabilizer of the model and consequently break the stabiliser. That is of course by my expirience but if you are willing to try, be my guest.
I think that the suggestion about bringing the weight of the rubber to 25g and then to 20g highly excessive. Regarding that the quality of rubber hasn’t improved in the last 13-15 years, i think that the weight reduction for 10% i.e. to 27g is completely acceptable.
Potential reduction of the time of engine operation might be acceptable at a glance. The only thing I don’t understand is why put down the limit to 4 seconds. Why not to 4,5 or 4,3 seconds? There are already problems with measuring the time at 5 seconds limit. Consequently the mistakes and problems will be even bigger. The other reason why I don’t understand it is that the model won’t reach 4/5 the height it used to but less. According to my tests, the classic model in the four seconds engine running reached about 75% of the previous height and the folder only reached around 65-70% of the previous height.
But the thing that I am at most unpleseantly suprised is about the idea to reduce the maximum diameter of the air intake of the motor to 4,5mm. This size of intervention does not only require the change of the diffuser but the replacement of the propelers and the existing engines with completely new ones, because the current engines are modified to higher quantity of air intake due to the dimension and shape of the intake canals. That means a purchase of totally new engines, that are modified to the smaller intake of air and new propelers if we wan’t to cope with competition, which I believe you know, is not very cheap.
Only people that could benefit from this ideas are the manufacturers of the engines and propelers, because it brings them lots of new clients and lots of business. The cost of buying new engines and propelers for 4 models would cost from 3000€ to 4000€ at least. Accepting this suggestion will probably be the final blow in the F1C category, because I can assure you that there are not many competitors who are willing to buy completely new engines and propelers so they can cope with the competition. It is just to expensive.
You need to realize that every suggestion which suggest modifications of models, engines or F1B propeler heads only means fresh hit to competitors wallets, and especially to the quantitiy and massiveness of our sport.

At last I think that there should be more people involved and cooperate with those changes and suggestions such as the wider part of the competition and expert FF comunity and not just the inner circle of people who are in CIAM sub-committe.
I Strongly suggest that you send new ideas and suggestions into discussion not only to the CIAM delegate but also to the competition organizers and prominent individuals, so that the circle of those who can forward their opinion and suggestions is as wide as possible. At the end the delegates of seperate countries should formulate the opinion of the majority of their membership and as such forward it to the president or the coordinator of the sub-committe. They should then on the foundations of this opinions formulate coordinated proposal to consider and approve at the CIAM convention. For every change cuggestions in all competition groups there should also be voting inquired at the plenary CIAM sessions. To my knowledge, that’s how they are managing at rocket modelling group.

The most important thing of all is that, before approving new rules and changes, there should be absolutely necessary to test the changes on the field, so you can se how the changes are affecting to the models, and consequently evaluate them to the extra costs for the competiors.

Some thoughts on F1A:

– Draggier/thicker towlines/pennants will make flyers build up tension instead of speed, launches will still be very high and force flyers to be very very fit – older flyers will not be able to tow.
– 5 Minutes towing time will cause people to stop towing and look for thermals before, either using F1B/F1C equipment or piggy backing, in either case defeats the purpose of this class.
– A 4 minute first flight will hurt older flyers and not change anything for younger ones with modern models – again defeating the purpose.

Shlomi Rosenzweig

Need a set of Vasi Mini-Bone F1H-compatible wings

Bad stooge tricks destroyed mine on Sunday. Tail and fuselage ok, mostly looking
for wings, but if you have one you aren’t flying, I’d be interested!

Greg in Mississippi greg stewart>

Heads up For the Patterson

Don’t forget it is Tule fog season in the San Joaquin Valley so there could be delays if you are driving up in the morning.

Fab Feb World Cup

There will be a an entry for package for the 3 Fab Feb events “real soon now”.

The “week” starts with the Ike /Kiwi on Sat 7 Feb – with F1ABCQ
and ends the following Presidents day weekend the Maxmen F1A on 13 Feb, F1BC on 14 Feb , Mini-events 15 Feb and reserve day 16 Feb. North American F1ABC during the week and the same with the F1E events. Full schedule soon too.

Judging by the enquires we have had it looks like a record turn out and the first rounds of another epic World Cup series.

Roger Morrell