Precision Payload rules
Precision Payload Competition comprises three events open to single-staged model rockets that wholly enclose the specified payload(s) for each class. The purpose of this competition is to accurately predict both the altitude and duration that a model will attain while carrying a payload of given mass and dimensions and recovering the payload without damage.
28.2 Payload Types
Precision Payload Competition specifies two payload types:
- Standard Payload, a non-metallic cylinder as described in Rule 25.2
- Fragile Payload, a hen’s egg as described in Rule 26.1
28.3 Model Requirements
The model cannot separate into multiple components – Rule 15.2 applies. No form of external control may be used to regulate flight altitude or duration. A contestant may enter only one model. In case of catastrophic failure the contestant may enter a replacement model per Rule 11.5.
28.4.1 Standard Precision Payload
The entry carries one fully enclosed Standard Payload to a target altitude of 150 meters and target duration of 40 seconds.
Weighting Factor 16
28.4.2 Fragile Precision Payload
The entry carries one fully enclosed Fragile Payload to a target altitude of 300 meters and target duration of 60 seconds.
Weighting Factor 20
28.4.3 Dual Fragile Precision Payload
The entry carries two fully enclosed Fragile Payloads to a target altitude of 500 meters and target duration of 90 seconds.
Weighting Factor 24
The altitude data provisions of Rule 14 and timing data provisions of Rule 15 apply except where otherwise noted here. The score for each qualified flight shall be 1,000 points minus the altitude and duration errors. The altitude error is the absolute difference between the recorded altitude and the target altitude in meters. The duration error is three times the absolute difference between the recorded duration and the target duration in seconds. The formula for computing a flight score is:
S = 1000 – ABS(TA – A) – 3 * ABS(TD – D)
S is the score for the flight
A is the flight altitude in meters
TA is the target altitude in meters
D is the flight duration in seconds
TD is the target duration in seconds
ABS(…) is the absolute-value function
The score for the event shall be the sum of the scores for up to two official flights. The highest event score is the winner.
The model must be returned after the final flight to verify that the payload(s) were retained within the model and that the fragile payload(s), if applicable, are undamaged. Rule 10.4 does not apply. A model need not be returned after the first flight unless an impound, or other rules such as the altitude data provisions of Rule 14.10.2, require the return.
A contest official shall inspect the payload(s) after the final flight. If the official cannot examine the payload(s), the entry is disqualified. If the contestant removes the payload(s) in the absence of an official, the entry is disqualified. If the official determines that there is any damage to the payload(s), the entry is disqualified. All entries must comply with the provisions of Rule 16.7 regarding human intervention in egg lofting events.