National Free Flight Society

SEN 1981

Table of Contents – SEN 1981

  1. Moose Cup
  2. Wanted
  3. Got used to it
  4. The rules of golf
  5. golf ball
  6. The numbers are the wrong way
  7. New Sidus F1C Timer
  8. Square Booms for F1A

Moose Cup Flash

F1_ Pos FAI Licens Name Country TOT
F1A 1 50520 John Carter GBR 1908
F1A 2 3214 Janne Savolainen FIN 1901
F1A 3 71391 Kosma Huber SWE 1693
F1B 1 42 Bror Eimar SWE 1440
F1B 2 3639 Juhani Isotalo FIN 1369
F1B 3 291 Tönu Luman EST 1359
F1C 1 38 Raimond Naaber EST 990
F1C 2 39 Juri Roots EST 778
F1Q 1 2139 Andreas Lindner GER 990
F1Q 2 3895 Jukka Juslin FIN 928
F1Q 3 831 Ossi Kilpelainen FIN 831
F1_ Pos FAI Licens Name Country TOT
F1A 1 73605 Robert Westerlund SWE 1269
F1A 2 464 Karl Mannik EST 1248
F1A 3 657 Gert Nulk EST 845
F1B 1 463 Riho-Ast Saatväli EST 1298
F1B 2 YL471 Vladislav Dreier LAT 925
F!B 3 539 Aleks Moistus EST 850

Swedish Moose Cup 2015 (World Cup)

FROM: Robert Hellgren

Hi Roger, please find the full results from Swedish Moose cup at the webpage:

BR, Robert Hellgren


From: John Cuthbert

Hi Roger,
Would you please be kind enough to place the following WANTED ad in your next issue of Scat news:

Wanted: Verbitsky three blade geared F1C engine. Please contact John Cuthbert on

Got used to it
Peter said it all! Great response. Couldn’t agree more.

Malcolm Campbell

The Rules of Golf
From: chris.edge
To: Sen, New

Baron SCAT,

I sadly must correct my fellow Brit and Squire of Taft, Lord Allnutt. The
rules of golf have significantly restricted technology in recent years,
with limitations applied to ball dimple symmetry, radius and depth, all to
ensure that performance doesn’t outstrip the field, er, I mean course. If
FF had followed a similar path to golf then CIAM would have restricted
turbulator size, position, and probably the chin of your chin (on the
airfoil, not your face). The same rule restrictions to limit performance
has been true in other sports such as tennis, F1, and the Haggis World
Series. In fact arguably FF has seen less restrictions in recent years, but
then sometimes the facts do get in the way of a good story.


golf ball
From: Gil Morris
Peter, un-be-knownst to most, there is a group developing a “drone golf ball” expected to go tee to hole in a single stroke.
The cost is untouchable except for Tiger Woods who could then surpass Jack Nicklaus’ record. The PGA is aware of this threat and has learned that to make the hole in one the golfer has to impart enough energy to the ball to reach the hole. (The ball will be able to destroy excess energy by unnecessary maneuvers such as loops and spins in transit). So, to combat the threat, the PGA is considering making 18 hole golf courses 9 holes with tee to hole nominally 600 yards instead of 300 yards. Even Tiger Woods couldn’t muster that. Thereby, the threat is averted. Back to square one

Editor’s Comment – Gil has gone way past the haggis eater, good to see the EoB out classed by a F1C flyer

The numbers are the wrong way around
From: Douglas Galbreath

I enjoyed Peter’s musings about golf. I love this guy.
Other than that, my first thought was Golf’s tools cost about $500 bucks and last place in a golf tournament pays about $125,000. F1 is the sorta other way around.

Douglas Galbreath


Outstanding new features are built-in 10cm accuracy altimeter/variometer and hi-power LED flasher control.
Wireless programming interface, long-range built-in RDT and contactless start switch remain standard also with the new product.

With the new SIDUS F1C G2, the flight data stored in the e-timer control board can be promptly analyzed after landing through the SIDUS G2 wireless programmer.
The new menus to analyze the altimeter/variometer data are simple and straightforward, and the well known procedure to set/read the timing of the disc steps has not been changed.

A new option has been added to read the built-in altimeter, so the TIMER and ALTIMETER functions are accessible separately for a quick learning curve of the new features.


Displayed data are:

– Apex height reached at the end of climb
– Maximum climb rate
– Average sink rate during glide
– EFT (expected flight time) from model release to landing
– Full set of sampled data: actual altitude and climb/sink rate can be analyzed sample by sample
– History of the apex altitudes recorded for the last 20 flights

All the displayed data are “timestamped” to accurately analyze climb, transition and glide. This is a big help to compare different models, engines, props etc.


One more feature coming with the new SIDUS F1C G2 e-timer control boards is the capability to power and control an external LED flasher that can be enabled/disabled through a new menu in the Sidus G2 programmer. The LED flasher can be installed permanently and enabled just if needed.


Care has been taken to keep compatibility of the new product with the existing one, with minimum investment for existing SIDUS customers who want to use the new system and keep their current equipment or gradually replace it.

– New SIDUS G2 programmers are capable to work both with new SIDUS F1C G2 and existing SIDUS control boards.
– Existing SIDUS programmers (hardware version 4.0 or later) can be upgraded to work exactly like the new ones.
– Existing SIDUS control boards cannot be upgraded with an altimeter, but as stated above they will keep working with the new or upgraded SIDUS G2 programmers.

For further information and details please email me at info

Rectangular F1A tail booms

At the Maxmen I timed the Israeli Junior Omri Schechter in the F1A flyoff together with Yuhuda Zack (the El Al Captain). Omri had a perfect launch and as the model bunted it DTed. Yuhuda said 29 seconds which turned out to be a perfect prediction. Evidently this is a known phenomenon in models with a stab is controlled by a level mounted on a pulley. The bunt angle is say 80 degrees, while the DT angle is a bit higher, say 85 degrees. Evidently, the pulley wheel over rotates. I felt sorry for Omri, but he seemed to take things in stride, placing 23rd out of 58.

At a high enough speed a sudden increasing the stab’s AoA will generate considerable lift. Brian Eggleston has estimated and demonstrated that bunt maneuver can considerably deform a tail boom. And when the tail boom deforms upwards, the lower braded steel line is further away from the geometrical center of the deformation, causing the pulley to rotate clockwise – triggering a DT instead of a bunt.

A round tail boom is the perfect form for twisting, which is why it’s used for F1B motor tubes. However, it’s a poor shape for bending relative to a rectangular shape. (Think about main spars in a wing.) So instead of the standard tail boom with a diameter of 14-15 mm down to 7-8 mm, consider a rectangular tail boom starting with say 15 X 15 mm square, down to a 10-12 (height) X 5-6 mm rectangle at its end. Such a rectangular tail boom will resist bending forces much better and will allow more of the pulley wheel to be embedded in the tail boom. Such tail booms are a bit heavier (larger surface area) and will cause a very slight increase in the model’s drag. (Making a stronger round tail boom is even a heavier solution.)

Once rectangle F1A tail booms are produced I’m sure they will become popular. (Similar logic applies to F1B tail booms that tend to break at their base or just before their fin in DT landings.)


How would a vertical web inside a round boom work ?

Editor ?

Roger Morrell