E20 Rules:
The Peterborough MFC have flown with a few different E20 rules over the years. The original class was known as Ferry 500 using a specific motor & battery. In 2019, the broader Open E20 Rules were established to allow any motor set up. In 2022 members began experimenting with the US-style NFFS E20 Rules, which specify an 8.5x20mm coreless motor and single cell LiPo.
Most PMFC Ferry Meadows competitions are flown with the Open E20 Rules which suit small fields. The Ferry 500 rule is now obsolete, but these models can still enter the Open class. Monday competitions at Buckminster and International Postals include events for both Open E20 and NFFS Rules. NFFS Rules are likely to be adopted for future competitions in the UK.
Open E20 Rules (2024)
This is an electric free flight development class where experimenting with different power systems is encouraged.
Models must have a maximum 20" projected wingspan (the previous maximum 20" overall length rule has been dropped.)
Any motor, battery, propeller and timer are permitted.
Motor run will be less than 8 seconds.
Models must have a dethermalizer fitted.
No minimum or maximum model weight.
Competition comprises of three flights to a max decided on the day (up to 60 seconds.) A flight of less than 10 seconds will be considered an attempt.
NFFS E20 Rules
US-Style E20 with a restricted motor and battery.
Maximum projected wingspan: 20 inches
Minimum Weight: 28.4g (1oz)
Motor: 8.5mm x20mm Coreless, no gear drives
Battery: Single Cell LiPo (no capacity limit)
Propeller: maximum 2.7” diameter
Motor Run: 20 seconds (Fly offs 10 seconds)
No auto-surfaces other than dethermalizer
Three flights to a 90 second max, Fly off max increases in 30 second intervals
Full Rules can be found at the National Free Flight Society: https://www.freeflight.org/free-flight-rules/
International Postal Competition Rules
can be found at: https://www.e20world.com/postal-winter-warmer-23-24
Ferry 500 Rules (Historical)
This is an electric free flight class flown on a fixed power system to provide a level playing field for small field competition.
Models must have a maximum 20" projected wingspan (not flat span) and a maximum 20" overall length including propeller.
Any airframe design is permitted within the above limits.
Models must fly with a specified motor, propeller and timer.
For the 2019 competitions these will be:
GWS CN12-RXC 7.2V or N60 25500RPM 6-7.2V 12mm brushed can motor
3x2" direct drive prop
Peterborough FET fixed motor run timer (details here: https://peterboroughmfc.org/Ferry500-Timer.html )
Battery must be a minimum of 2S 180mah Lipo.
Motor run will be fixed at approximately 8 seconds.
The timekeeper is responsible for ensuring the motor run in flight is 8 seconds or less.
Models must have a dethermalizer fitted.
No minimum or maximum model weight.
Competition comprises of three flights to a max decided on the day (up to 60 seconds.) A flight of less than 10 seconds will be considered an attempt.
For 2019 the motors are available to PMFC members on proof of a viable model. The recommended battery is a Turnigy Nanotech 2S 180mah (25-40C)
(Ferry 500 is no longer flown by the PMFC as a separate class but the rules are included here for historical interest.)