National Free Flight Society

SEN 1978

Table of Contents – SEN 1978

  1. MaxMen Q and Minis
  2. North American 2015 Report
  3. Ron Felix’s 25g F1B Experiment
  4. Altimeter Comment

Remaining Maxmen Results – Q plus the Minis

Max Men 2015 F1Q
Place Name Nat 1 2 3 4 5 6 7 Total
1 Shmuel Sitton ISR 180 180 180 160 180 180 180 1240
2 Ian Kaynes GBR 180 137 180 180 180 180 180 1217
3 Jack Murphy USA 180 134 180 180 180 180 180 1214
4 David Lacey USA 111 180 169 180 180 180 20 1020
5 Aram Schlosberg USA 180 145 180 28 180 180 9 902
6 Matt Gewain USA 180 79 143 0 0 0 0 402

MAX 180 180 180 180 180 180 180

Number of maxes in the round 5 2 4 3 5 5 3

Number of competitors with full sco 5 1 1 0 0 0 0

Max Men 2015 F1G
Place Name Nat 1 2 3 4 5 FO1 FO2 FO3 Total
1 Blake Jensen USA 120 120 120 120 120 180 300 356 1436
2 Tiffaney O'Dell USA 120 120 120 120 120 180 300 300 1380
3 Stepan Stefanchuk UKR 120 120 120 120 120 180 300 298 1378
4 Peter Brocks USA 120 120 120 120 120 180 300 291 1371
5 Gil Hagay ISR 120 120 120 120 120 180 300 279 1359
6 Abraham Baruch ISR 120 120 120 120 120 180 300 256 1336
7 Or Shabat ISR 120 120 120 120 120 180 236 1016
8 Evgeny Gorban UKR 120 120 120 120 120 180 178 958
9 Bernard Guest CAN 120 120 120 120 120 180 133 913
10 Geralyn Jones USA 120 120 120 120 120 180 117 897
11 Ladi Horak CAN 120 120 120 120 120 176 776
12 John Clapp USA 120 120 120 109 120 589
13 Didier Chevenard FRA 120 120 96 120 120 576
14 Sevak Malkhasyan (JR) USA 120 120 74 120 120 554
15 Kurt Van Nest USA 92 113 104 120 104 533

MAX 120 120 120 120 120 180 300 420

Number of maxes in the round 14 14 12 14 14 10 6 0

Number of competitors with full sco 14 14 12 11 11 10 6 0

Max Men 2015 F1H
Place Name Nat 1 2 3 4 5 FO1 FO2 FO3 Total
1 Per Findahl SWE 120 120 120 120 120 180 300 233 1313
2 Aviv Balassiano ISR 120 120 120 120 120 180 300 223 1303
3 Avner Studnik ISR 120 120 120 120 120 180 300 167 1247
4 Shmulik Sitton ISR 120 120 120 120 120 180 300 151 1231
5 Brian Van Nest USA 120 120 120 120 120 180 278 1058
6 Jim Parker USA 120 120 120 120 120 180 205 985
7 Chris Edge GBR 120 120 120 120 120 180 174 954
8 Phil Mitchell AUS 120 120 120 120 120 180 137 917
9 Robert Wallace NZL 120 120 120 120 120 180 0 780
10 Brian Lavis GBR 120 120 120 120 120 97 697
11 Tuvia Fibish ISR 111 120 120 120 120 591
12 Mike McKeever USA 111 106 120 110 120 567
13 Gary Madelin GBR 120 80 120 120 120 560
14 Shachar Limor ISR 107 75 120 120 120 542
15 Kathy Burford AUS 120 45 120 120 120 525
16 Blake Jensen USA 120 120 120 120 1 481
17 Omri Shechter (JR) ISR 120 120 120 0 120 480
18 Malcolm Campbell AUS 48 93 0 0 0 141

MAX 120 120 120 120 120 180 300 420

Number of maxes in the round 14 13 17 15 16 9 4 0

Number of competitors with full sco 14 12 12 11 10 9 4 0

Max Men 2015 F1J
Place Name Nat 1 2 3 4 5 Total
1 Randy Secor USA 120 105 120 114 120 579
2 Glenn Schneider USA 120 93 120 120 120 573

MAX 120 120 120 120 120

Number of maxes in the round 2 0 2 1 2

Number of competitors with full sco 2 0 0 0 0

Report on North American Cup 2015

North American Cup 2015

The midweek event of the Fab Feb World Cup competitions at Lost Hills is the North American Cup run by the Toronto Free Flight Group. Each year the atmosphere around these 3 World Cup contests is like a slightly smaller scale World Championships and this year was no exception with sportsmen and sportswomen from around the globe descending on Lost Hills to play with their models in the desert. A large contingent from Israel had made the trip and were enjoying the California weather. It was nice to see a full Japanese F1B team flying very well throughout the week. When entry was over there were flyers from 23 countries ready to do battle!

54 in F1A, 47 in F1B, 14 in F1C and for the first time at the NA Cup we had F1Q with 5 enthusiastic flyers!

The feel was more like a World Championships than a World Cup contest.

The forecast for the NA cup was excellent, with very light winds from the North West predicted for the morning. Tuesday morning dawned cool (9 to 10 C) with very light winds but from the opposite direction than predicted so the flight line was located near the campers. The contest began with near perfect conditions, sunshine, very little drift and buoyant air making the extended morning maxes a mere formality for most of the flyers.

I spied a new F1C model from Artem Babenko with the wing located along the centreline of the fuselage. The wings were all moving and of course were folding, all carbon wings as per Artem’s previous recent creations. It was interesting to note that the very thin, highly cambered F1A style airfoil employed a half round turbulator moulded into the surface of the wing. From what I saw the model was an excellent performer.

The weather held and many maxes were recorded with large flyoffs expected in the near perfect conditions. Sunshine, blue skies and 24 C with many thermals were available. There had been many informal discussions about model performance all week, but it must be said that the weather made a huge difference. In the conditions experienced throughout the Fab Feb, large flyoffs should be always expected. I did see Stepan Stefanchuk (Ukraine) and Ladi Horak (Canada) practicing with 20 and 25 gram F1B rubber motors. Ladi put up a test flight with a 25 gram motor in the middle of one of the practice days and reached over 200 meters on the climb in the large thermals always present in the afternoon at Lost Hills. When you combine exceptional weather with great flyers you have to expect many, many maxes.

Round 5 began and the wind finally switched to the expected North West direction putting several F1A models into the orchards. After consulting with the Jury, we decided to delay the start of the 6th round while we moved to the North about 1 ½ miles away to take the orchards out of play. The move went smoothly and round 6 got underway with massive thermals and a steady increase in wind speed.

After round 7 there were 30 flyers in the F1B flyoff and 20 in F1A. Only 4 had made the F1C flyoff leading to a few jokes that perhaps F1C did not have enough performance and a 6 second engine run was proposed on the spot to “help” the poor F1C sportsmen.

Despite the near perfect conditions there were no max outs in F1Q. Perhaps the new, lower energy limit was holding back performance?

While the location for the flyoff was ideal, the wind speed had increased to about 5 m/s. This meant that a 7 minute max might bring the orchards back into play. The jury suggested a 5 minute flyoff max but upon further discussion, it was decided to move the flyoffs to the following morning as 1 m/s winds were predicted so that a 10 minute maximum could settle things.

The flyoff was scheduled for Wednesday morning at 7:00 a.m. The temperature at dawn was cool (7 to 8 C) with very light drift of aprox 1 m/s. Visibility was not ideal at 7:00 a.m. with significant haze so the F1A flyoff was delayed for 10 minutes and the haze lifted. The top flyers were all using LDA models or flappers and many spectacular launches were observed. Roland Koglot (SLO) showed his mastery of the morning flyoff with a magnificent 468 second flight. Per Findahl (SWE) and Jim Parker (USA) were tied for 2nd with identical flights of 419 seconds so an additional flyoff, head to head would be required to settle 2nd and 3rd places after the other flyoffs had completed.

The F1C flyoff was next and Artem Babenko (UKR) showed the full potential of his new model with a magnificent flight of over ten minutes! Evgeny Verbitsky (UKR) was 2nd and Ron Mcburnett (USA) was 3rd.

F1B was next and some of the best F1B flyers in the world showed how it was done. Alex Andriukov (USA) showed why he is still the F1B king with a clear victory of nearly a minute over Michael Siefert of Germany. Russell Peers (UK) had a superb flight for 3rd place. I watched a very determined Alex break motor after motor (5 in all!) before finally getting his flight off near the end of the round. He was clearly “going for it” and he wasn’t holding back anything!

The F1A flyoff for 2nd and 3rd place got underway immediately following the F1B flyoff and Per Findahl had a near perfect launch to defeat Jim Parker with 377 seconds to Jim’s 337 second flight.

The North American Cup is unique in having a team event with 3 flyers from each event vying for medals to decide the best team. Often the teams are made up from various countries and some good friendships are forged on the field.

The top F1A team was Per Findahl (SWE), Roland Koglot (SLO) and Mike McKeever (USA) showing that the craft Mike knows how to pick team mates well….

2nd place in F1A team went to the team of Ken Bauer (USA), Lauri Malila (SUI) and Jari Valo (FIN)

3rd place in F1A team was taken by the team of Jim Parker (USA), Brian Van Nest (USA) and Peter Barron (USA) 2/3rds of the current USA F1A team for Mongolia.

The top F1B team was the German/Ukrainian/USA team of Michael Seifert (GER), Stepan Stefanchuk (UKR) and George Batiuk (USA but now residing in Germany)

2nd place in F1B team went to the team of Cameron Ackerley (CAN), Ron Felix (USA) and Evgeny Gorban (UKR)

3rd place in F1B team went to the Israeli team of Or Shabat (ISR), Gilad Mark (ISR), and Gil Hagay (ISR)

The top F1C team was taken by the formidable trio of Artem Babenko (UKR), Alexander Vyazov (RUS) and Evgeny Verbitsky (UKR)

2nd place in F1C team went to the trio of Roy Summersby (AUS), Taron Malkhasyan (USA-JR) and Alan Jack (GBR)

3rd place in F1C team went to the team of Jeff Ellington (USA), Gil Morris (USA) and Roger Simpson (USA)

The top junior flyer in F1A was Gil Yair (ISR)

The top junior in F1B was Troy Davis (USA) with a max out! Unfortunately, Troy was unable to participate in the flyoff as he had to get back to school!

The top junior in F1C was Taron Malkhasyan (USA).

Special thanks go to Alex Farkas who helped us with score keeping, Roger Morrell and Lindy Murrell, Marty Shroedter for the tent, and Walt Ghio for the lovely trophies.

There was plenty of champagne and snacks for the winners and I didn’t hear any discussions about rule changes at all!

Please join us next year!

Tony Mathews and Peter Allnutt (Canada)

25 GRAM F1B – Ron Felix, 02-23-15

For those who are interested, here is my report on my flying experiences at the 2015 Max-Men with a simple, 25 gram F1B model. (“25 Grams of Rubber”, as proposed by Poland, and “Release the Propeller before Launch”, as proposed by Britain). This report provides details on the model that I flew, how it performed, and who flew 25 grams along with me. It also includes evaluations that were made for each change to reduce performance, and finally what were my overall impressions.

My model was: A 155 cm Icarex covered Stefanchuk wing, 28 mm diameter Kevlar tube fuselage (with a 453mm or 17-7/8 distance between the centerlines of the bobbin and the stirrup of the roller hook), aluminum/carbon Tailboom, self-build 2.77 dm Gorban style stab, standard Stefanchuk fin, Stefanchuk pylon with mechanical timer, and a backwards Montreal front end with Vivchar fish-net carbon propeller blades from several years ago. The front end and blades weighed 33.5 grams, and 24.4 grams of lead were needed to bring to model weight up to 205 grams! As to the front end, it is one that I have flown extensively and it operated reliably in four (4) USA Team Finals in late 1990’s to the early 2000’s – as well as in many other competitions. To be clear, it is also one without a ratchet, DPR, or variable pitch. Launching the model was done by holding the fuselage VERTICAL with my right hand, holding the propeller at the hub with my left hand, then releasing the propeller – and once the left hand was clear, pushing the model vertically upward.

The model was adjusted on the afternoons of the 11th and 12th of February, and used motors that were 11-3/8 inches (288mm) make-up length. This is my standard length shorted by the ratio of 25/30. During trimming, the wing wiggler was locked out. The stabilizer had three (3) functions – burst setting, then a cruise and glide setting actuated after about 4 seconds, then D/T (dethermalize) after 180 seconds. The auto-rudder was two-position – straight for power, which was then actuated for a right hand glide circle after the end of the motor run. This was adjusted to achieve a 35 – 40 second circle. The Vivchar blades were set to the typical 29 degrees at 200mm radius. Motor runs varied from 32 – 35 seconds depending upon the strength of the motors used. The model was adjusted to fly in the late afternoons, with light thermals and some wind. In summary, this was a model very similar to what I flew from 1993 to the early 2000’s – and one that would meet BOTH of the proposed rules presented to the CIAM – and some further rules as proposed by some of the British Sportsmen.

The contest day for this model was at the F1G flight line on Sunday, the 22ndof February. I took the model out of the box, assembled it, and put in three flights without making any adjustments for calm air. (For Ross’s and maybe other readers’ benefit, we typically increase the overall incidence of the model by screw adjustments to the hammer at the trailing edge of the stabilizer on calm mornings (or change weights). We also typically open the glide circle to over 1 minute. This slows down the glide and helps improve performance. We then typically work our way back to the thermal and wind settings by round 3). These adjustments were NOT made, as flying this way is perhaps the way a beginner would fly with a simple F1B model – or if the first round was windy or turbulent. However, on this day, it was neither turbulent nor windy. Three flights were made between 8:00 and 9:00AM to measure and determine the average performance available. The results were: Flight 1, 8:14AM = 3:55 (315 turns on the motor, 13 torque on an AA winder, 32 second motor run, in uniformly lightly buoyant air, with very little wing rocking). Flight 2, 8:31AM = 4:17 (330 turns, 14 torque, 35 second run, 38 second glide circle. Note that for this flight, I took out .003 inches (0.076mm) of down thrust on the 28 mm diameter nose ring to slow down the cruise. The air was buoyant, with noticeable wing rocking throughout the flight). Flight 3, 8:45AM = 3:34 (330 turns, 13 torque, 36 second run. The air was not buoyant. The air was sinking when the prop folded, settling down to a layer of buoyant air, wings rocking, at about half way to the ground. Then at approximately 10 meters, the model descended in sinking air).

In summary, During Round 1, from 8:00 – 9:00AM, the three flights provided an average performance of 235 seconds – with the model adjusted to thermals and light wind conditions. All three (3) motors used showed very many light cuts and nicks. Motors were 1/16 inch from the April 2012 batch. This rubber improved after two years of aging, and yielded a specific energy of 4,558 and 4,616 ft x lbs / lb via torque testing two random 30 gram motors. (This is good rubber!)

I then flew four (4) more Rounds: Round 2 = 2:59.38. This time was shown to Geralyn Jones via my wrist watch stopwatch, which I started after launch. It is also noteworthy that I flew with Geralyn almost concurrently on this flight. When I asked her what she thought of the air, she felt that this air provided an easy 2 minute max with her F1G. In my case however, it was a very close call for an F1B with 25 grams, hand start, and a 3 minute max! Round 3 = 180, with a 3:06 D/T at 10 meters. Round 4 = 180, with D/T at 2 meters. Round 5 = 180, with a monster max – D/T at over 100 meters. A sixth flight was also flown at 1:00PM just for the fun of it, with a monster max of 180.

During this 25 gram competition, NOBODY joined me in flying the five rounds with simple models! I was not surprised, as when I originally built similar models for Wawayanda competitions some year ago, it was to “Dumb Down” so others might join me in flying. At that time, NOBODY joined me – in contrast to their protests at that time of: “We do not fly the event because it is too complicated and/or too expensive”. This seems to be the same story we are hearing today! My advice to the voting representatives is that with all the discussion and comments that have and are taking place in this electronic age – the decision makers must separate what is “Talk” from what is “Real”. I would also hope that input from Contest Directors (ones with significant experience and having a history of overseeing and administering well run competitions), provide input into the rules making process.

To assure that the record is complete and correct, Ladi Horak made several flights with 25 gram motors using his standard model, as did Bernard Guest. In observing these models, they flew similar to 30 grams, but did not get as high. Both Ladi’s and Bernard’s models (VP and DPR) may have needed some very small adjustments – Bernard’s maybe more so. However Ladi’s comment was: “The models fly the same, only they don’t get so high”! This was said with an implied “No problem – if we go with 25 grams – but with our present models, which have a ratchet, DPR and VP!

Now what are all these changes or reductions on the “Dumbed Down” model worth in seconds of performance?

First: 25 grams/30 grams = 83.3% of our current performance. Taking the three flight average of the “Dumbed Down” model” of 235 / .833 = 282.1 seconds – if 30 grams of rubber was used.

Second: Since the “Dumbed Down” model was flown without a ratchet, holding a wound motor without ratcheting for 1 minute will provide only 96.8% of the potential energy available. This is compared to fully wound motor, expediently tested without waiting. (This energy measurement was done as part of a series of tests for Fred Pierce in April of 2008, involving torque testing 30 gram motors held wound for different lengths of time). For those who are interested, two (2) minutes wait = 95.6%, four (4) minutes wait = 91.6%, and 10 minutes wait = 91.7%. So let’s say one (1) minute is lost after winding. This involves positioning the bobbin on the half tube, disconnecting the winder from the bobbin, transferring the half tube to the model, putting the model back on the stooge to connect the prop, pushing the backwards Montreal stop pin into the stop hold to serve as a waiting stop, walking to the flight area, releasing the waiting stop, then launching the model. For the “Dumbed Down” model, if we used 30 grams of rubber, 282.1 / .968 = 291.4 – if we now also ratcheted.

Third: My estimated average delay for releasing the propeller with my left hand and throwing the model vertically is about .25 seconds. Since most motors average about 20 revolutions per second during the burst, 20 x .25 = 5 high torque turns. (Note: Although the peak speed of rotation is on the order of 28 revolutions per second (rps), the prop needs to accelerate from zero to this rotational speed. So, 20 rps was used as a very rough approximation). However, considering that I “warmed up” by being careful during the first three flights, let’s say 20 rps x .30 seconds = 6 revolutions. Six (6) high torque turns yields 84/1522.5 inch x ounce x turns – (ref: A not shown here rubber motor torque test, Test 2, dated 04-21-08). This yields 5.5% loss of energy, or 94.5% reduction. Therefore for the “Dumbed Down” model, if we used 30 grams of rubber, and ratcheted, 291.4 / .945 = 308.4 if we now instantly started or used Michael’s wire hook!

In conclusion, a fixed pitch, ratcheted, but non-DPR 155 StS Model doing 308 (5:08) with the described trim, in calm air, and with good rubber, seems reasonable. So, I would conclude that the reductions via each technology element as described above are probably good approximations.

Impressions of flying this model with 25 grams, no ratchet, and hand start, with a 3 minute max, left me with the conclusion that it is MORE difficult than flying F1G with its 2 minute max – This was by watching F1G models when I was flying, and particularly in light of Geralyn’s comments and her model’s performance. Practically speaking, if this becomes the new rule, I think there would be many dropped flights, and flyoffs would be considerably smaller than they are today. Satisfaction with models flown to these specifications would be considerably less than flying with current models – as we would be nervous and worrying that we would make 180 on many more flights during contest rounds than we do now! Alternatively, we would have to adapt to not making flyoffs regularly, but have to gather satisfaction in striving for every bit of performance via very careful trimming, concentrating more on the weather at launch time, and possibly making improvements in aerodynamics. I would also suspect that this could create a greater differential between beginners and the top very experienced competitors – and that luck would play less of a factor (as is the case sometimes today, when the majority max out in good conditions, and whoever picks the best air in the 7 minute round wins). Should some of these rules be implemented, we will be dropping more flights if: We are not perfectly trimmed, do not have a high performing model, or do not very carefully pick our time to fly.

In summary:

The model was built to weight, 155 cm wing, trimmed for wind/thermals, 25 grams, no ratchet, and hand start. Flight testing showed that the model was worth 235 (3:55) with maybe some helpful air, between 8 – 9 AM. Flying this model in rounds, one can make all 180s with careful flying – but with some close calls!

A 25 gram motor will provide a performance level of 83.3% of what we have now. Using no ratchet will by itself provide a performance level of 96.8% of what we have now, assuming you launch the model within one minute after winding. Using a hand start by itself, assuming six (6) turns lost, will provide a performance of 94.5% as compared to Instant Start or Michael’s wire hook. Using 25 grams of rubber with a hand start will probably provide a performance of .833 x .945 = .787 or 78.7%. Therefore, seven (7) minute models would become: 420 x .787 = 330.5 (5:31); and six (6) minute models would become 360 x .787 = 283.3 (4:43), and five (5) minute models would become 300 x .787 = 236.1 (3:56) – that is if a rule change to come involves both 25 grams and starting the propeller by hand before the model is launched.

Utilizing or keeping DPR and/or VP could add more to the base performance of the “Dumbed Down” model estimates. Allowing “Instant Start”, Michael’s wire hook, or other similar method would cancel some or all of the 5.5% loss described above via the hand start.

Overall, the event would become different. Making the flyoff would be a more special achievement, and I am sure we would all have to work harder to get there.

Altimeter Comment

Hello there;

The altimeter would probably need to be equipped with a transmitter
periodically sending the altitude you could see on your receiving
device. Even then it probably can’t tell you how far it is above
the ground, just how high or low it is compared to the launch height.

For information beyond that it would need something like GPS that can
compare the model’s position vs. the device you’re holding.

Craig Limber

Roger Morrell