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  1. The 20-second rule
  2. 20 seconds = Risk vs Reward
  3. Stefanchuk’s new wings
  4. Stepan on   Stefanchuk’s new wings

The 20-second rule

From: aram schlosberg

There are a number of CIAM proposals from European countries (whom attend the CIAM meeting in late April) to abolish the 20-second attempt rule across the board. The impetus stems the concern about its “misuse” – a quick RDT in a poor launch, although the success rate is rather low.

A zero tolerance means a wipe out when:
In B, when the prop does not start, or a motor blows just after launch.
In C, when a lean engine cuts off just after launch; similarly in Q.
In A when an eager helper glides the model before the tower is ready. (Miss communication.)

In my opinion, a zero tolerance would have retarded many technical developments. For example, a delayed prop release in B, the development of spectacular A launches.

Actually, the 20-second rule was abolished once (30 years ago?) and reinstituted a year later. And since then RC capabilities have evolved, they could be subverted to jetting off a non-essential model part, such as a latch cover, achieving the opposite result. (RC an attempt, or RCA).

An obvious fix to the perceived “problem” is to state that the 20-second attempt rule only applies to cases where the model has not DTed.


20 seconds = Risk vs Reward
From counter argument

At the high standards that we expect from participants in the World Champs why give them a break if they choose to employ a risky technology or technique or some tech jiggery pokey to get an attempt. What’s the difference between picking bad air and bad preparation of your F1B so the prop did not start, none it’s a mistake so why reward one but not the other.

We say there are too many in the flyoff so why reward those who should not be there?

Stefanchuk’s new wings

From:sergio montes
On Stefanchuk’s new F1B wings,

In his report on the  Fab Feb meetings,  Chris Edge mentioned the superlative glide performance of these Stefanchuk wings. Can anyone enlighten us on what make these wings so god? Choice of airfoil, chord distribution, method of construction? Details would be of great interest to many of us.

Sergio Montes

Editor’s Comment – I sent Sergio’s email to some of the people involved (see Stepan’s comments below) . The wing has a Brian Eggleston airfoil – not a true LDA to my understanding but that needs confirmation. The wing layout is by Tony Mathews.

Also at the Fab Feb was a similar looking wing made by Stepan to Mike, the Dino Achterberg’s specs. Same constructions as theabove. This has a different airfloil and layout. It is larger with a smaller tapered stab in classic Dino configuration. Very nice stab with the carbon dbox and contoured tips all one piece.

Stepan on   Stefanchuk’s new wings
From: Stepan Stefanchuk
Hi Roger,

Thanks for your letter. It’s very nice to hear good words about my flights. Yes, indeed, my new model has a very good glide  flight.

With this model, I had 3 wins at the end of 2016 at the World Cup stages.
I could tell more in LH. But, unfortunately, few people had an interest in this model. Now it’s hard for me to write. My English is bad.

These wings are a project from Tony. Tony can tell more information.

Also I can add. I had fears that the full carbon wings are very fragile. That, after flying on the surface, we will have a lot of damage ….  But that is not happening. Full of Carbon wings can fly many seasons.




The F1E California Cup otherwise known as Bob White Memorial MaxMen International
F1E has been rescheduled for Thursday October 5th, 2017 at Lost Hills.

Also during that time we will have Kotuku Cup F1E Friday October 6th and Sierra Cup F1E Tuesday October 10th.

More info at soon or email Brian VanNest

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Roger Morrell