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NAR S&T MOTOR DECERTIFICATION NEWS


Effective immediately, Estes E15 motors with date codes
of 13X10 and 15X11 are decertified for general and contest use.
In April 1994, Estes Industries officially recalled E15 motors
with these two date codes. MESS data collected by NAR Standards
and Testing since August 1994 substantiates this action.


Only these production lots are immediately decertified.
If you possess these motors, Estes asks that you contact your
local retailer for a product exchange in accordance with the recall
announcement issued by Estes to its distributors and retailers.


Due to a year long production hiatus, all other Estes E15
motors will lose contest certification on 1-July-95, except
for contest use at NARAM 37. General use certification will
expire in three years, on 1-July-98, per S&T decertification policy.


At the time these motors are reintroduced, they will undergo
a full certification test as if they were new, first-time motors.


Jim Cook, Secretary for
NAR Standards & Testing

IIRC, there was a casing problem (too large of an ID?) that casued the propellant to casing bond to fail after they finished drying ("curing") after many months. The new E9 underwent EXTENSIVE casing testing, as did the 13, 18 and 24mm motor line. They even added an extra code to motors to indicate casing manufacturer as they fielded casings from 2 different manufacturers so they could track failures if they occurred.