Brushed and Open Class Rules for TRF Winter Electric League 2008/9

The Electric Winter League for the 2008/9 season will consist of three classes:

Class 1. A competition for models of any size which are powered by Brushed (ferrite) motors (also of any size). The competition rules are a variant of the BARCS rules applicable to SLG competitions:

• An Open class for models powered by ferrite brushed motors of unrestricted size
• No restriction on model wing span or weight
• A battery energy limitation of 10.25 Watt hrs for models with an all-up weight of not more than 1Kg.
• Heavier models will be allowed higher battery energy as shown in the attached table up to a limit of 20.5 Watt hrs for models exceeding 1.5 Kgs.
• 3 slots per winter league round with a 30 second power-on time & no re-charging between slots
• Each slot to be of 10 minutes duration inclusive of power-on time
• 1 point to be scored per second of flight up to max of 600
• Landing bonus of up to 50 points for landings within the landing circle
• Penalty of 1 point per second for landings exceeding the slot time
• Over flying the slot time to also forfeit landing bonus
• The dates for each of 6 rounds to be set at the start of the winter season with 3 reserve dates scheduled in case of inclement weather
• No rescheduling of rounds beyond those pre-allowed as reserve dates
• League result to be decided on the best 4 rounds by each competitor, or fewer if rounds are lost to the weather
• A Round shall be flown provided: a) at least 3 entrants are prepared to fly AND b) The organiser considers flying would be safely undertaken (it would not be safe to fly in rain, hail, snow or fog).

Class 2. An Open competition for models of any size/weight or electric motor type

The Rules for Class 2 will be the same as class 1 except that Brushless or brushed motors (ferrite or otherwise) will be allowed. The competition will consist of 3 slots.

Class 3. (200 Watts/Kg class)

A competition open to all electric, hand launched models. This will be designated the 200 Watts/kg class where energy consumption will be restricted to a maximum of 200 Watts/Kg of the model’s flying weight. No model shall be permitted to operate at more than 400 Watts maximum. Models shall be subject to weight and power consumption checks prior to competition to ensure compliance with these rules.

• 3 slots per winter league round with a 30 second power-on time & no re-charging between slots
• Each slot to be of 10 minutes duration inclusive of power-on time
• 1 point to be scored per second of flight up to max of 600
• Landing bonus of up to 50 points for landings within the landing circle
• Penalty of 1 point per second for landings exceeding the slot time
• Over flying the slot time to also forfeit landing bonus

Table for calculating maximum battery size for a TRF winter League Electric model 2008/9

Flying Weight	Max batt Energy	Max Battery capacity allowed in mAhours
Of Model	(Watt Hours)
		7 cell Nicd/Nimh	8cell Nicd/Nimh	2cell LIPO	3 cell LIPO
0 to 1kg	10.25	1460	1280	1600	1070
1Kg to 1.25 Kg	12.8	1830	1600	2000	1330
1.25 to 1.5 Kg	15.4	2200	1925	2400	1600
1.5Kg and over	20.5	2930	2560	3200	2130
The above has been determined using the BARCS Standard for SLG competitions where battery
energy limits have been set at 10.25 Watt hours but a variety of battery types can be used to
achieve the 10.25 Whrs energy limit. Barcs has set some assumed voltages for different cell types
and these have been used in the table above The BARCS assumptions are:
1cell of Nimh or Nicd = 1volt (under load) and 1 cell of LIPO or LION = 3.2Volts. Barcs is currently
debating a variation in the rules to allow larger, heavier ARTF types to compete by allowing an
increase in battery energy with increasing weight of model. The above table has broadly followed
the current BARCS proposal but allows a little more power to the heavier models which would
otherwise not be able to compete when power - on time during launch is reduced to 30 seconds