SEN 2463 - SEN 2463 - Table of Contents Thinking about Pieter while performance pondering, reading a German Web Site and wishing you were in Colorado.

SEN 2463 - Table of Contents

Thinking about Pieter while performance pondering, reading a German Web Site and wishing you were in Colorado.
  1. D/T Fly Off Thoughts
  2. Model performance reduction and model performance measurement
  3. Pieter de Boer R.I.P.
  4. The German Freeflight Magazine has relaunched it's webpage
  5. Swedish Suggestions
  6. MMM 14 rounder report

D/T Fly Off Thoughts

From:Colin Sharman

Hi Roger,

As a currently ‘retired’ UK F1A flyer, including being an ex British team
member and supporter at various Euro and World Champs, I have followed the
current and controversial D/T Fly Off debate with great interest.

IMHO the D/T Fly Off is an inadequate way to reach a result at the end of a
competition, it will produce random results based on variable D/T descent
rates, regardless of the height at which the models D/T, and to me is also
contrary to the fundamental principles of Free Flight which aim to produce
a winner based on the best combination of model performance and air
picking, particularly in a Fly Off.

Back in the pre-historic era of the early 1980’s, I developed a series of
F1As which features all sheet balsa wings, with a variety of composite
internal structures and wing finishes. These models were originally based
on the excellent Ivan Crha all sheet wing F1As, which if memory serves me
correctly, won the Euro Champs in 1980, (Andy Crisp, and perhaps CHE will
know the precise details and date of Ivan’s Euro Champs win with instant
recall and flawless memory!!).

A feature of my sheet wing F1As was that the tail D/T angle was critical, a
few degrees either side of the optimum 35 or 36 degrees would produce
either a tumbling D/T if the angle was slightly too high, or if the angle
was too low, a disastrous ‘spinning leaf’ descent which would very quickly
turn into a wingtip over wingtip tumbling effect, which usually resulted in
a fast descent crash landing on one wingtip.

At that time a fellow club Cheltenham MAC member was a retired Farnborough
theoretical aerodynamicist and mathematician (Mike Redler RIP), and after
witnessing the ‘spinning leaf’ disastrous D/T descent he went away and did
endless calculations, and came up with a very simple and effective
modification to my F1A’s, which cured the hyper sensitive D/T angle issue

This modification did not affect the overall design of the model, did not
affect the glide or circle towing characteristics at all, and added about
2gms to the all up weight. It meant I could set a wide range of D/T tail
angles without any danger of it developing into the dreaded spinning leaf
style descent.

The reason for rambling on like this is that it occurs to me that if the
D/T Fly Off becomes commonplace, or heavens forbid, becomes an official
part of the Sporting Code, then Mike Redler’s simple innovation could
become invaluable in being able to set a slower descent rate for D/T Fly

I am reluctant to publicly divulge the details of this innovation (although
Andy Crisp will no doubt recall it immediately), even though I have a vague
memory that it may have been included in an article and drawings of my
‘Warrior’ all sheet wing models that were published in Free Flight News
sometime in the early 1980’s, as I don’t particularly want to make freely
available a technique that would encourage the use of D/T Fly Offs.

If anyone wants to investigate the ingenious Mike Redler solution on their
current F1As, I can be contacted at ‘This email address is being protected from spambots. You need JavaScript enabled to view it.’, that
way it could even be regarded as a visible way to easily check if any given
F1A is being fine tuned for tactical D/T Fly Offs...

And my suggestion to the world wide challenge of fewer and smaller flying
sites, and large Fly Offs that need a huge amount of space and many skilled
timekeepers? Fly all Champs and World Cup events at either Lost Hills,
Mongolia, or perhaps some of the sites that are used in Russia, then
controversial issue of D/T Fly Offs would be completely irrelevant!

By the way, up until retiring from running a world wide software business
in 2016, I regularly flew from London to Tokyo, which involved flying at
around 500 MPH for about 8 hours over Siberia, looking down on endless,
vast, treeless, open sites which could swallow hundreds of F/F contests
simultaneously....just a thought!

Big Thermals on Big Sites!!

Colin Sharman.

Model performance reduction and model performance measurement

From:Leo Reynders

Model performance reduction and model performance measurement

In order to solve the problem of measuring the performance of our ever
improving models many proposals have already been issued to reduce the
performance of our models. However, instead of focusing on reducing the
performance of our models, we could also focus on improving the way we
measure the performance. Historically, measuring the flight time was the
ONLY way to measure the performance. Presently, the availability of
altimeters creates new possibilities: We could for example measure the
altitude of the model after 1 minute and after 2 minutes. By extrapolating
the data, a ³virtual² flight time could be calculated for flights that
exceed 2 minutes.

One could argue that a virtual flight time is not ³exact². True but also the
³real² flight time does not give an exact rating of the performance. For
example, maxing after catching a thermal at very low altitude after 2
minutes flight: The resulting ³max²  has nothing to do with the performance
of the model nor the competitor, it is only a question of being lucky. I
don¹t think we are interested in knowing which competitor has most luck. We
are interested in the competitor that performs the best launch and that uses
the best model (sinking speed). Both can be assessed within 2 minutes flight
time by using the virtual flight time.
So, in my opinion, the virtual flight time will give a better picture of the
performance than the real flight time.

One could argue about the reliability of altimeters: To handle this concern,
models could be equipped with two altimeters, one belonging to the
competitor end one that is offered by and returned to the contest

One could argue about the accuracy of the altimeter. Indeed but also time
keeping is not that accurate: Time keepers could time the wrong model or
could not be able to see it the whole flight. If the model disappears behind
e.g. high trees, it becomes even impossible to measure the real flight timeŠ
By taking two altimeter readings, one after 1 minute and one after 2
minutes, calibration errors are neutralized and only non linearity errors
remain, which look to me acceptable in view of the advantages of using
virtual flight times.

By allowing altimeter based virtual flight time measurement we could stop
the pressure to reduce model performance. We could go back to longer F1C
motor runs. We could freely choose the maximum (virtual) flight time, not
being limited by the size of the field. We could organise contests on
smaller fields, so we could organise contests on more locations. We would
need less model retrieval efforts and time keeping effort would be limited
to two minutes. Models would climb less high in thermals so less concerns
about exceeding a maximum allowable altitudeŠ

Of course, there are also disadvantages: time and effort to process the
results, equipment cost, Š It is mainly to the contest organizers to
evaluate whether they can handle
At the end a balanced use of real and virtual flight times, depending upon
conditions (field size, wind speed, number of competitors,..), might be
optimal or at least a good alternative for a DT fly-off.

Leo Reynders

Pieter de Boer R.I.P.

From:Leslie Farkas

On behalf of the Canadian modellers, I would like to express our sincere condolences to the Pieter de Boer family. Pieter’s kindness and professionalism will be dearly missed. His passing left a gaping hole in our sport.


The German Freeflight Magazine has relaunched it's webpage

The German Freeflight Magazine has relaunched it's webpage:
The new version is now adapted to the mobile devices as smartphones and
tables as well as to a desktop.
We have slightly modified the menu to make it more transparent.
As new features we have added a special area for news and reports from clubs
and there is now a possibility to download a sample copy as pdf.
Best regards

Bernhard Schwendemann

Good news for the FFWC, but heavy rule stuff.

From: Bror Eimar

The original of this document was written in Microsoft Word making use of a feature that enabled the hiding of some text. This was used to hide specific Sporting Code text and references.  That way is not possible with how SEN is distributed so we have  used a different formatting. The inclusion of this information makes the paper longer but the editor think that it important to include these references.

The FAI Sporting Code rules permit DT Flyoff. Other Local Rules in Exceptional Circumstances are also permitted. For Entrants and Competitors this should be clear.

However, comments in recent days have shown that it is necessary to issue some further clarifications on the FAI Sporting Code, particularly with respect to our Free Flight World Cup events. Free Flight World Cup events are important in maintaining participation in FAI Free Flight events.

According to SC4 CIAM General Rules, the World Cup is a classification of the results of specific Open Internationals during a year.
C.2.2.3 World Cup This is a classification of the results of specific Open Internationals during a year.
A World Cup may be organised by the relevant CIAM Subcommittee for any of its classes. There must be at least five valid contests held in any class of World Cup for FAI medals and diplomas to be awarded. Classification for any particular category is contained in the World Cup regulations in the appropriate Volume of the FAI Sporting Cod

It is very important to get a conclusion of an World Cup event. The result of one World Cup event can affect the placing of sportsmen in the overall World Cup even if those sportsmen are not present.

Contestants must have a valid FAI Sporting Licence. There are requirements for competitors/entrants.

FAI Sporting Code General Section. 3.1.2. The holder of a Sporting Licence acknowledges that he knows and understands the FAI Sporting Code and commits himself to abide by it. Only holders of a valid FAI Sporting Licence are permitted to participate in FAI sporting events, record attempts and badge flights.

FAI Sporting Code General Section.   Competitor responsibilities.  All competitors entering sporting events under FAI rules shall accept that they may be required to submit to, and co-operate with, doping control measures.  Entrants with a documented medical condition requiring the use of a Prohibited Substance or a Prohibited Method must before the event concerned have obtained a Therapeutic Use Exemption (TUE) in accordance with FAI Anti-Doping rules.  In addition, for reasons arising during or immediately before the event, a competitor taking any drug or medication, or suffering from a medical condition, illness or injury, which might either compromise safety or invalidate a licence, must inform the Contest Director in writing before competing.

The FAI CIAM Sporting Code Championship Rules are comprehensive. They can't be applied with the normal Championships format that applies to our FF World Cup contests without considering the FAI Sporting Code stated local rules for exceptional circumstances.
CIAM General Rules 2018 Edition,


C.13.2 Local rules

Local rules in exceptional circumstances:
a) may be established at, or imposed by, the Plenary Meeting for championships in the same or the following year, or by the organisers;

b) may not change the model specification or contest rules unless agreed at the Plenary Meeting;
c) must be published in bulletins, preferably in advance of entry deadline, but no later than the latest bulletin made available to all competitors;
d) decided after this point, must be issued to competitors in writing prior to the start of the event;
e) may be established during the contest as necessary.

Implications of this is that, for instance, the DT Flyoff and Group Flyoff are allowed to use in exceptional circumstances, in World Champs, Continental Champs and Free Flight World Cup contests.
A list of changes due to the FFWC format with limited contest organisation could be helpful.
There could also be a clarification paragraph in the FFWC Rules with a new number and heading.


11. Rule Exceptions.
a)  Competitors time each other. All round flights and flyoff should be timed by two timekeepers. In     flyoff competitors are allocated a group, timekeepers and starting position by a single draw.
    Jury is selected by the CD from contestants. A competing jury member is not entitled to deal with     his own contest event. (CIAM General C.7.3, General C16.1, Section 4, F1.1.2.b and c, F1.2.4a     and b, and F1.A2.7).
b)  Random model checks may be performed. (CIAM General C16. 1b), Section 4, Volume F1.3.1).
c)  The CD will use the flying field responsibly to minimise risks for contestants and models. (CIAM    General C16.1 h).
d)  The contestants themselves agree on the starting order. (CIAM General C.16.2.6).
e)  FAI sticker and markings as for Championships: The owner's Name, National ID code, National     Licence No. (25 mm) and the model parts identification code (10 mm). Model Aircraft     Specification Certificates are not required for FFWC contests. (CIAM General C.11).
f)  The organiser must make available a printed English version of the SC rules. (CIAM General C.16.2.6).
g)  Local rules may be established during the contest as necessary. (CIAM General C.13.2 e) page  33).
h)  Moving along the starting line is not necessary for FFWC. (Section 4, Volume F1.1 b).
i)   Each competitor is entitled to five or seven official flights. The number to be flown must be     announced in advance in the invitation. (Section 4, Volume F1 3.1.3 a, page 14).
j)  Organisers announce in invitation changes from the guide, (Section 4, Volume F1 Annex 2, 3.A2.1,     page 47), such as may be necessary to suit local circumstances. It should be approved by the appointed FAI Jury for a FFWC.
k)  For travellers that can't carry their own F1C or F1P fuel, it can be requested from the organisers in advance for cost. (Section 4, Volume F1 Annex 2 3.A2.4.5, page 51).
l)    For travellers that can't carry their own F1Q bigger charging batteries, for example 12 Volt, it can     be requested from the organisers in advance for cost.
m)  CD may use Group Flyoff to get a conclusion of a contest within the timetable, according to:
Section 4 – Aeromodelling Volume F1 Free Flight Model Aircraft 2016 Edition, 3.1.8.f.
    f)  If the number of competitors in a flyoff is 12 or more and is greater than 25% of the number of competitors in the competition, then the flyoff may be split into two groups:  
    1) The number of competitors in each group will be as closely as possible equal.  
    2) Competitors are allocated a group and starting position by a single draw.
    3) A flyoff is flown for each group according to the other regulations of 3.1.8.
    4) The second group flyoff must be flown as soon as possible after the first group.
    5) From both groups all flyers who achieve the maximum duration proceed to the next round.
    6) An equal number of flyers from each group may proceed to the next round by including     competitors from one group those with the best flights below the maximum time, providing the  flight times are at least 75% of the maximum.
    7) If the selections (5) and (6) result in fewer than 4 competitors proceeding to the next round, then   the two competitors with the highest flight times in each of the groups will proceed to the next  round.
    8) Competitors eliminated in group flyoff will be classified with final placing according to time   achieved in the group flyoff 3.
n)    CD may use DT Flyoff to get a conclusion of a contest within the timetable. (Section 4, Volume F1      Annex 2  3.A2.1, page 47,
3.A2.1. Objective This document is intended to specify guidelines for the organisation of outdoor free flight international contests, for the benefit of both the organisers and the competitors. It is emphasised that recommendations are given and these do not have the same status as the binding regulations in the FAI Sporting Codes. However, since it is widely distributed and should be regarded as the standard for international competitions, organisers should avoid confusion by announcing in advance any changes from this guide such as may be necessary to suit local circumstances. These changes should be approved by the CIAM Bureau for a Championship or by the appointed FAI Jury for an Open International event.  

This guide is applicable to World and Continental Championships in classes F1A, F1B, F1C and for Junior Championships at which F1P is flown in place of F1C. Organisers of Championships should note the administrative advice given in the CIAM General Rules on the organisation of Championships. For organisers of FAI Open International events, appendix A gives changes and comments appropriate to Open Internationals for classes F1A, F1B, F1C, F1P and also F1G, F1H, F1J, F1Q, and F1S.  
Where this guide refers to the FAI Sporting Code Section 4 the relevant paragraph is quoted in brackets.).

    The organiser will establish a format of the DT time and number of seconds overtime penalty, to be      stated in the Contest Announcement. The flying time to DT and landing are to be timed separately.


Non acceptable rule changes. As stated in SC4 CIAM General Rules C.13.2, Local rules in exceptional circumstances:
b) The organisers or CD may not change the model specification unless agreed at the Plenary            Meeting.
This makes it difficult to, for example, increase model empty weight, shorten the starting cable or to shorten the engine run.
Also the model stab DT angle setting would be up to the contestant as well as adjusting the rudder setting or the stab or wing incidence setting before a flyoff.

Remember that exceptional circumstances include high wind and wind gust speed, rain and/or snow, reduced visibility and daylight, other exceptional weather or flying field conditions, dangers for models and retrievers in the landing area and shortage of available contest time.

Bror Eimar
Contest Report: 39th Annual MMM 14-Rounder Contest
by Pete McQuade (Co-CD with Jerry Murphy)

The 2018 edition of the MMM 14-Rounder kicked off on Friday, June 22 at our Indian Point F1E site north of Quincy Ave. This was the F1E Team Selection Finals combined with our F1E World Cup Contest.  John McGrath was CD and Chuck Etherington was the Head Jurist. Wind speed and direction varied significantly throughout the day, making things challenging, but we were still able to get in five rounds.  The 2019 US F1E team of Bob Sifleet, Peter Brocks, and Tom Ioerger will travel to Martin, Slovakia for the World Championships in August of next year.  Good luck, guys!
The placings in the F1E World Cup Contest were as follow:
  1.  Bob Sifleet
  2.  Rick Pangell
  3. Peter Brocks
  4. Mike Richardson
  5. Tom Ioerger
Saturday:  Centennial Cup FAI  (Note:  a broad slate of AMA, NFFS, and SAM events were also flown both Saturday and Sunday.)
Saturday was one of the finest flying days in several months at Lowry, with high temperatures in the upper 80s, moderate winds, and great thermals.  We had visiting fliers from five states: Bob Sifleet from Indiana; Tom Ioerger and Mike Richardson from Nevada; Tiffaney O’Dell and Blake Jensen from Oregon; Allan Mecham and Jack Murphy from Utah; Jim Farmer and Peter and Brigitte Brocks from Arizona.  Of course, we also had a hearty contingent of local Colorado fliers.
Jim Farmer came seeking to complete his 75 minutes of qualification time for the F1A Team Selection Finals this October.  Assisting Jim and also flying Nordic was his son Sam, who now lives in Colorado.  Great was the excitement as Jim’s Round 7 flight drifted to the west and worked its way to a max, garnering the time he needed to qualify.  Afterward, Jim rushed to DIA to catch his evening flight back to Arizona.
Ably assisted by the ever-cheerful Brigitte, Peter Brocks also flew well in F1A, but had the misfortune of losing his glider in the strong lift of Round 7.  Unfortunately, hours of searching by Peter, Don DeLoach, Mark Covington, and Jace Pivonka weren’t able to recover the model.
Mike Richardson and Blake Jensen battled it out in F1B on Saturday. In addition to maxing out in F1B that day, Blake impressed everyone with his towline artistry and his amazing bunts in F1H.  He regularly put the blue-and-white, two-servo glider into good lift.
F1G competition was fierce, as expected, and Don DeLoach and Tiffaney O’Dell both maxed out on Saturday.  Their flyoff for the Centennial Cup was held at 7:30 the next morning in cool, breezy conditions.  Tiffaney found the better air, posting an impressive 218 seconds to win.
The F1Q electric flyers were in great form, and sub-max flights were rare.  Bob Sifleet maxed all seven rounds to take the Centennial Cup.  In F1S, Jack Murphy and Allan Mecham showed us how it’s done—they both maxed out, with Allan winning the flyoff later that afternoon.

Sunday:  Columbine Cup FAI
For days, the meteorologists had predicted gloom and doom for Sunday—cold, rain, and high winds.  But when Round 1 began at 8:00 am, the flying conditions were beautiful, with warm, light breezes; even better than Saturday had been!
Jace Pivonka started well in F1B, with three straight maxes.  Blake Jensen dropped a little time in Round 1, but it was still anybody’s game.  Pete McQuade had a good start in F1A with maxes in all of the first three rounds.  In F1Q electric, Jack Murphy of Salt Lake City had a string of three maxes going.  But Tom Ioerger was hot on his heels.
As expected, F1G was hotly contested Sunday, with Don DeLoach, Tiffany O’Dell and Mike Richardson regularly clocking 120s.  After three rounds, Tiffany and Mike were still clean.  At the same time, Blake Jensen had built up a solid string of maxes in F1H.  Don DeLoach was still clean in F1S, but Jack Murphy, Jerry Murphy, and Allan Mecham weren’t far behind.
Just before the start of Round 4, the weatherman got his revenge.  Within the next two hours, three separate thunderstorms clobbered us from different directions.  After frequent checking of cell-phone weather apps, a few contestant meetings, and advice from Tiffaney O’Dell’s contacts in suburban Denver, we ventured outside to start a much-delayed Round 4.
Peter Brocks was first out of the muddy starting blocks, towing his F1A.  Amazingly, he hooked onto good lift and his glider was soon drifting quickly to the south.  Blake put up a max in F1B to edge out Jace for the Columbine Cup in that event.  In F1Q, Jack Murphy raked in a fourth straight max to win.
The F1G fliers followed suit, with Don DeLoach, Tiffaney O’Dell, and Mike Richardson all scoring 120s.  This put Tiffaney and Mike in a tie for first place in the Columbine Cup, with perfect strings of four maxes each.  They agreed to have their flyoff on another day and in another place, to be determined.
In F1H towline glider, Blake made his fourth max of the day to finish with a perfect 480.  Don DeLoach and Jack Murphy made their fourth-round maxes in F1S electric, with Don clean for the day.  This put him 19 seconds ahead of Jack and won the Columbine Cup for him.
The winners of the 14-round FAI perpetual trophies and the 8-round mini-FAI silver cups were as follow:
F1A      Pete McQuade
F1B      Blake Jensen
F1C      Chuck Etherington
F1Q      Jack Murphy
F1G      Tiffaney O’Dell
F1H      Blake Jensen
F1J       (not competed)
F1S      Don DeLoach
Overall, this year’s contest was a most enjoyable and memorable free flight festival highlighted with great flying and wonderful camaraderie.  And the barbecue catered by Apple Junction Smokehouse both days was phenomenal.  If you missed this contest, come on out next year!