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TCC NAR Competition Primer:

USMRSC Rule 9.13 FAI Events

USMRSC Rule 15.12, Multi-Round Duration Events (PD-MR, SD-MR, HD-MR, SRD-MR, BG-MR, RG-MR, FW-MR)



What are the USMRSC Rules for FAI Style Events?

USMRSC 9.13 defines the rules for Fédération Aéronautique Internationale (FAI) style events in NAR competition. The FAI sponsors world-wide model rocket competition. The NAR has included rules in the USMRSC to introduce NAR members to FAI competition and to help prospective FAI competitors to practice FAI rules and techniques while flying NAR competition. Find out more about FAI Spacemodeling at .

9.13 FAI Events

Models flown in the FAI class of an event, except for Boost Glider (*), must comply with the following construction requirements of the FAI Sporting Code, Section 4, Volume SM Space Models for that event. First, the minimum length of the enclosed airframe of the model must be 500 millimeters and at least 50 percent of this airframe length must have a minimum diameter of 40 millimeters in the launch configuration. Second, in events where multi-staging is allowed the booster stage must deploy a recovery device, the upper stage must be at least 18 millimeters diameter over at least 75 percent of the upper stage length, and any boat tails on that stage must be at least 18 millimeters in diameter.

(*) “except for Boost Glider” was unintentionally omitted from the original RCP, and was added as a Rules Interpretation, by Rule F.8.B.

FAI Streamer Duration has an additional rule 31.2.1 that defines the FAI streamer:

31.2.1 FAI Streamers

For FAI class streamer duration, the streamer must have a length-to-width ratio of ten to one (10:1) or greater. The cord attaching the streamer to the model may be attached to a loop of thread which is attached to each edge of the narrow end of the streamer.


Which are the USMRSC Rules for Multi-Round Events?

USMRSC 15.12 defines Multi-Round scoring and return. Multi-Round adds an extra dimension to scoring. You can use up to two models for up to three official flights. If there is a tie for First Place, the contenders go into sudden death flyoff.


What is the Goal?

The rules for the base event (PD, SD, HD, SRD, BG, RG or FW) are unchanged.


Are There Any Special Considerations?

* The USMRSC allows you to use two different models. If one flies away, you then use the other one. USMRSC 15.12.2

* The Contest Director can require contestants to fly in a designated time interval or round. If you can’t fly in your designated round, you’ll get a zero score for that round. USMRSC 15.12.1


Do I Have to Return My Entry?

* You don’t have to return your entry unless the Contest Director requires you to. USMRSC 9.10

* You have to return one of your first two flights in order to have an entry for your third flight. USMRSC 15.12.1


How Many Flights Can I Make?

* You can make three flights. USMRSC 15.12.1


How is the Competition Scored?

* Each round has a maximum duration. If your entry achieves a longer duration than the maximum, your score is the maximum score. For example, the maximum for A PD-MR (A motor parachute duration, multi-round) is 180 seconds. If your entry achieves 179 seconds, your score for that round is 179. If your entry achieves 360 seconds, your score for that round is 180, the maximum score. USMRSC 15.12.4

* Your score is the sum of your three official flights. USMRSC 15.12.4

* If there is no tie for First Place, the contestant with the highest score places first and the contest officials will award second through fourth places as usual. USMRSC 15.12.4

* If there IS a tie for First Place, the contenders for First Place will have the chance to make more flights (flyoff rounds) to determine the winner. USMRSC 15.12.4

* The Contest Director will add one minute or more the event maximum to set a new maximum. USMRSC 15.12.4

* The First Place contenders will make one flight (flyoff round). If there is a tie for First Place, the CD will add one minute or more to the new maximum and conduct another flyoff round. This continues until there is no tie for First Place. Otherwise, the contest officials will award First Place to the winner of the flyoff round. USMRSC 15.12.4

* The contest officials will award second through fourth places first to contenders in the flyoff round(s), even if their score is lower than that of a contestant who did not fly in the flyoff round(s). After places have been awarded to the contestants in the flyoff round(s), the contest officials will award any remaining places, based on the total computed score, to the other contestants who made a qualified flight. USMRSC 15.12.4


What are the Maximum Durations for the Multi-Round Events?