23-Feb-24 - 10:22 AM

Thermal Circle Text - Thermal Circle 15

Written by Hayden Daley - 12 September, 2007.
In this edition of the soaring circle we will take a look at the competition rules for soaring events flown in Australia they are F3b F3jF3f and Australian open thermal.These are the major soaring events contested, and get a large turn out to all events and are exciting to watch, prompting this topic for this particular issue. It has been a while since I have flown competitions, my main passion is aerotowing large scale sailplanes so I have had to do a lot of research to complete this edition. The information in this edition is factual so is difficult to re-write so please forgive the similiarities I am only trying to pass on the information.I am also offering an invitation to any suppliers of soaring releated items if you would like your items reviewed, please contact Brian Green and I would be thrilled to review the item in the Soaring Circle.

F3b Rules Summary

The information for this column was taken from the internet so please excuse some similiarities to internet web sites there is only so many ways of typing the same information. The first f3b world championship was held in 1977 and since then many rule change have resulted in the rules evolving to there current state.The competition is multi task and The 3 tasks are

A :7 minute(soon10min) thermal flight with precision spot landing.
B 4 minutes distance flight over 150m closed circuit.
C Speed flight over 4x150metre course.

The three tasks are to be flown with the one model, the only physical changes allowed are the addition or subtraction of ballast making optimum design in the competive model very difficult. The current size for a competitive f3b model is around the 2.9 metre to 3.4 with many choices available for sale around the world. Most current models have a combination aileron, camber changing and brake functions spread over wing control surfaces. This is possible with modern computer radio controls as most pilot use different flap and trim settings for the different tasks and these modern radios allow for many different settings. Every task begins with a winch launch, hand towing is also allowed but rarely used it is only in extreme wind conditions where it can provide an advantage over winches but this is rare.There are strict laws governing winches preventing over power and jeopordising safety during launch.


All competitors are given preperation time and the contest director will allow 9 minutes working time for each round to acheive a 7 minute flight after release. The flight time begins when the model releases the line and in the event of a relaunch the last flight time counts. The flight should also involve a spot landing, this is in the rules and without a spot landing included your score will suffer dramatically.You will also score zero points in the spot landing if you interfere with the model before it is measured. The score normalised to the round score winner is a 1000 points and everyone in the round will receive a score normalised to this.


4 to 6 pilots fly at the same time. After the starting signal the pilots have 7 minutes working time to fly as much laps as possible within a 4 minute flying time. The laps are defined by 2 parallel at 150m distance equiped with signalling devices to signal when to turn and head back. The pilot with the most laps scores 1000 points and each other pilot in his heat will receive a percentage of this as his score.


In the speed task pilots fly the course one by one. Every pilot has 4 minutes working to complete the flight. After launch the pilot must try and fly 4 laps of the 150 metre course in the shortest time possible. The fastest pilot gets the 1000point and the rest are graded against this 1000 points. There is little time to climb in thermal lift as only 1 minute is allowed before the course must be entered and the run begun. The final results in f3b are tallied from these multiple tasks round and the score is tallied from all heats. This contest is exciting to fly as there is always something happening with pilot flying the different tasks and the contest director is kept busy tallying the score. With an Australian world champion in f3j it would be magnificent to see an Australian win an F3b world championship which is well and truly possible with an Australian acheiving a 14 second speed run during practice recently which is a world class time, almost a world record.

F3J Thermal Duration

This is a thermal duration class to provided man on man contest using thermal duration soaring gliders. In the contest qualifying rounds are flown and the competitors are divided into groups and the final result of the these qualifying is a fly off between the best pilots. Any model aircraft which is not provided with a propulsion device can be used in f3J and variation of size or area must be actuated at a distance. The maximum surface area is 150dm, the maximum flying mass is 5 kg, the loading of the model is between 12 to 75g/dm and the minimum radius of the fuselage nose is 7,5 mm. The radio must be able to operate at 20 khz spacing with other equipment. The competitor may use three aircraft in the contest and can combine the parts of this aircaft to make another working model. All ballast must be carried and fastened internally. No fixed or retractable arresting device is allowed on the model to slow it down likewise the underside must not have any protruberances other than the tow hook and linkages. The competition flying site must be a site having reasonably level terain, which will minimise the possibilitity of slope and wave soaring.The competitor will be allowed a minimum of five,preferably more, official flights. The competitor will be allowed two attempts at each flight. The competitor is entitled to a new working if his model in the process of launch collides with another competitor. If in the process of being launched the model collides with another competitors tow line. The flight is cancelled and recorded as a zero score if the competitor used a model aircraft in plain violation of the rules, the contest director may disqualify the pilot in this scenario. The working time allowed in a group is to be exactly ten minutes. The end of a groups working time must be audibly give as well as at the beginning. Any model aircraft airborne at the completion of the working time must land immediately. The contest director will not start the contest until all competitors have handed over all transmitters to the organisers. Failure to hand in a transmitter before the official starting of the contest may result in the competitor forfeiting his/her first round flight. Any test transmission during the contest without permission of the contest director is forbidden and will result in disqualification of the competitior. The competitor must hand over his transmitter to the designated official immediately after competing his/her flight. These strict transmitter laws apply to every f3j event. The models must be hand launched only and upwind in the marked launching corridor. An attempt is annuled and recorded as zero if the model is launched outside the launching corridor.The launch of the model aircraft will be hand held tow line only and it is illegal to attach the line to the ground or to any fixed object. The length of the towline shall not exceed 150 metres when tested under a tension of 20N. Tow lines for each competitor must be laid out only during the competitors five minute preperation time and must be retrieved by end of his or her working time. The towline must be made of monofilament throughout its length. It must have a pennant with an area of 5dm a parachute of the same area may be substituted as long as it remains inactive during the launch. The attempt will be timed from the moment it releases the launching device to the model first touches the ground or the model touches any object in contact with the ground and until the end of the flight or the end of working time. The flight can be completed with a zero landing score by overflying by more than one minute. If the model aircraft touches either the pilot or his helper during the landing no points are to be awarded. At the end of the rounds, a minimum of 9 pilots are to be placed in the fly off at the contest directors decision more pilots may be allowed to compete.

F3F Slope Racing

Again please excuse similarities with web sites there is only so many ways to type the same information. F3F is speed event for radio controlled slope soaring gliders. A minimum of four rounds must be flown for the event to have a result, any less than four rounds and the event is declared a non event. The competing sailplanes must have the following charecteristics, a maximum surface area of 150dm2,a maximum flying weight of 5kg and a wing loading of between 12 and and 75g/dcm2.The radio used shall be able to operate simultaneously with other equipment at the normal bandwidth, so 20khz in Australia. The competitor may use two models in the contest. The competitor may combine parts of these two models to make another if a disaster occurs and as long as the parts have been confirmed as from these checked models at the beggining. Addition of ballast and change of angles on models are allowed. Variation of geometry or area is allowed only if actuated at a distance by radio control. Competitor and helpers,the competror must operate his radio equipment personally.Each pilot is permitted one helper and the helper is only to assist and advise the pilot only until the model is passing base A for the first time and after the timed flight is completed. Definition of an attempted flight is when a model has left the hands of pilot or his helper.The pilot has one attempt on each flight however a flight can be repeated if the launch is was impeded hindered or aborted by the launcher and this was witnessed by the official judge and also if the flight was not judged by the fault of the judge. A flight is official but gets a zero score if the pilot uses an illegal model, one that does not conform to F.A.I rules. The model loses any part whilst airborne during a competition flight.The helper advises the pilot during the timed flight or the model is controlled by anyone other than the pilot during the timed flight. The model lands outside the assigned landing area. The model is not launched in time this is one minute from the start signal. The flights are to be performed round by round. The starting order is settled by draw in accordance with frequency this allows for preperation time of model without frequency clashes. The pilot is allowed three minutes of preperation time from the moment he is called to the ready box. After the three minutes has elapsed the starter may give the order to start.After the starter has given the order to start the pilot or his helper must launch the model within one minute and the model must be launched by hand. The time from launch to the moment the model enters the speed course must not exceed thirty seconds. The flying task is to fly 1000metres on a closed speed course of 100metres in the lowest possible time from the model crossing on to the course. The speed course is laid out along the edge of the slope and is marked at both ends with two clearly visible flags the organiser must ensure that the course is legal, that the flags are perpendicular to the slope. The flights are judged by two judges per flight however the judges do not have to be the same for each competitor. This is a timed event so the judges have little relevance as all the rules are well explained and any breaches will be easily judged and obvious to all competitors. Again this is an exciting event to watch and flown in windy weather is exciting as some of these slope soaring gliders really move. This is an easy event to run and hopefully more of the these competions wil be run by the soaring club.The major organisers of soaring competitions, the soaring circle email address, soaring@newlitho.com.au welcomes any information on competitions and will endeavour to publish any information on soaring competion.

Australian Open Thermal Rules

This is the name given to the Australian competition rules as flown a events like the annual L.S.F Jerilderie tournament. These are not all the rules only what I considered to be the major rules. These rules have evovled over the years to there current state and again please excuse the similarities with the internet text. The model sailplanes used in this event are allowed to have a flying mass no more than 5kg, a models maximum surface area is 150dm2 and a wing loading of between 12 and 75 g/dm2. The minimum radius of nose is 7,5 mm, a safety rule to prevent injuries caused by sharp noses on models. No arresting devices to aid in the spot landing are permitted . Any electronic device that transmits information to the pilot is not permitted, varios are out, meaning that pilot must judge whether the model is climbing or descending by sight only.The pilot may enter three models in the contest only however these parts can be interchanged to complete another working model if a disaster occurs and that the parts can be identified as entered at the start of the contest. For the sake of randomness of the starting order each pilot must enter two differerent frequencies and the competitior can be called on to change frequency as long as the call is made 15 minutes before the heat. The radio must comply with M.A.A.A regulations to apply to band width seperation of 20khz. The pilot must operate his radio equipment personally and each pilot is allowed four helpers. Attempts, for each task, during the working time allocated to him,the competitor is entitled to two attempts. An attempt starts when the model is released from the hands of the competitor or his helpers under the tension of the tow line. No change of model or parts of the model is allowed after the starting of this attempt.The competitor is entitiled to a re flight if his model collideds with another during the launch or during flight.The pilot is also allowed another attempt if an error in timing has been made that is no fault of the pilot. Also if an event that is no fault of the pilot has occured than a re-flight is again permitted. Unless otherwise specified a flight in progress will be cancelled for an infraction of any rule. In the case of fragrant violation of rules by any competitior or conduct not in the spirit of the event the contest director is entitiled to disqualify the competitier from the competition. The competitior may have the score of that heat cancelled any part of the model is lost during launch or during the flight. The competitor is disqualified if he does not control the model for the whole flight. If the model is touched during the landing zero points will be given for that heat. In the case of the competitors winch losing any part or the turnaround is torn from the ground no further attempts are allowed with this winch and this leads to the cancellation of the flight. The flights are to be placed in a draw to allow as many flights continuously as possible. The groups must be changed for every heat to allow for different pilots to fly as many different competitors per heat. In the case of protests the contest director may set a protest fee $20.00 is considerd appropriate and will be returned if the protest is upheld. Safety, the organisers must clearly mark out all areas with the appropriate areas clearly defined.All relevant MAAA and CASA safety directives must be observed. The organisers of major events should seek height clearances of 1000ft or more. The contest is a duration event for radio controlled gliders. A minimum of four rounds must be flown for a national championship.The launch of the sailplane can be from the following means hand towing,electrical powered winch and hand operated pulley. The winch line legth are to be 200 metres to the turn around and the hand tow line is to be 175 metres.The winch must meet the resisitance laws to be legal. All winches will be tested at major events using winch testing equipment.Battery voltage,current flow and voltage motor terminals shall be instantly displayed then recorded to enable the calculation of motor internal resisitance. The winch may be adjusted to legalitly with external resisitance but the resistor must not be possible to be overbridged if this is possible the winch is illegal. The power source to the winch is to be a 12volt battery. During launching operations hand towing of the model must be used with a "winding" reel to allow the line to be wound in, preventing crossed lines. Winch lines are to be wound down to the turnaround again to prevent crossed lines, a powered winch lying across lines and wound will "cut" the lines or severly damage them. Winch lines are expenscive, and this is not tolerated, if you cut lines expect to pay for them. The flight time is a 10 minute flight in 12 minute working time, this allow 2 minutes for launch. This is a challenging event and has evolved to Australian conditions,kind of like f3j but without the hand tow. These are 90% of the rules the rest were difficult to re-write. Thats it for this edition, I have enjoyed writing this as it has brought me up to date on the rules and I have tryed to cover as much as possible with out to much copying! Happy Soaring! Hayden Daley.

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Text-based competition soaring information website established 2007