A Glossary

catastrophic failure

A failure that, in the opinion of the judges, is not due to or caused by improper design, construction, or preflight preparations of the model. This can include a malfunction of the model rocket motor, a model being run over by a car or stolen, an irreversible error by a meet official such as a lost flight card, or a similar occurrence beyond the control of a contestant. This does not include improper assembly of a reloadable motor. A flight experiencing a catastrophic failure can be declared not to be an official flight. See Rule 11.5.

 

construction

The action required to complete a model starting with no more prefabrication than the amount used in the average kit. Model rockets that are completely prefabricated and require only a few minutes of unskilled effort for their completion, or in which many normally separate pieces are pre-assembled are not considered to require construction. One-piece plastic fin units are not prohibited per se, but as such depend on the of prefabrication of the rest of the model.

 

contestant

A NAR member or a team composed of NAR members entered in a sanctioned competition.

 

first motion

The instant at which a model begins to move upward under the thrust provided by a model rocket motor.

 

gross launching mass

The mass of a model rocket in flight condition, including fully loaded motor(s), but not including launching devices or auxiliary equipment which does not become airborne with the model.

 

misfire

Failure of a model to make an official flight when its launch is attempted. Failure to launch caused by a malfunction in a meet-provided launch system shall not be considered a misfire.

 

NAR Contest Board

Refers to the National Contest Board of the National Association of Rocketry. If a rule applies to action with respect to a Regional Contest Board, this is specifically stated.

 

pop lug

A launch lug or other fitting that guides the rocket during launch, but remains connected to the launcher, or falls from the model immediately after leaving the launcher.

 

pitch axis

An imaginary reference line through a model about which the model might rotate. On a typical model rocket, this axis runs side-ways through the body at the center of gravity. Since a model rocket is usually symmetrical around the roll axis, the pitch and yaw axes are usually indistinguishable. On a typical glider, the pitch axis runs side-ways through the fuselage or boom in such a manner that if the model, during gliding flight, were to rotate about the pitch axis, its nose would move up or down.

 

roll axis

An imaginary reference line through a model about which the model may rotate without changing its direction of travel. On a typical model rocket this axis runs down the length of the model, from the center of the nose cone through the center of the motor nozzle. On a typical glider, it runs down the fuselage or boom, from the nose to the tail, in such a manner that if the model, during gliding flight, were to rotate about its roll axis, one wing tip would rise while the other fell, and the model would bank to one side.

 

safety ruling

A ruling by the RSO, a deputy RSO, or (in limited cases according to Rule 11.1) the Contest Jury, denying an entry the opportunity to fly due to considered judgment that the model would be unsafe in flight; also a ruling that disqualifies a model which flies in an unsafe manner. If an RSO or deputy RSO, acting in the capacity of a flight judge, disqualifies a model for a reason other than unsafe or hazardous operation or flight, this is not considered a safety ruling.

 

stage

Any portion or portions of the model airframe containing one or more model rocket motors. An unpowered portion of the model is not considered a stage. Clustered motors that ignite at the same time, but may be contained in multiple airframe portions such as strap-on boosters which separate in flight (i.e., Delta, Soyuz), are considered to be one stage. Upper stages must involve ignition and separation from the airframe in order to count as an additional stage. Air-starting of one or more additional motors, which do not involve separation from the model, is not considered to be an additional stage.

 

yaw axis

An imaginary reference line through a model about which the model might rotate. On a typical model rocket, this axis runs sideways through the body at the center of gravity (see pitch axis). On a typical glider, the yaw axis runs vertically through the fuselage or boom in such a manner that if the model, during gliding flight, were to rotate about the yaw axis, its nose would move left or right.

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