CEDAR CITY, Utah USA — As a result of customer feedback and field experience, AeroTech is now requiring the use of a new 54mm "forward seal disk" (part no. 54FSD) with current production RMS-54/1280 J1999N-P and the 54/2560 K700W-P & K1275R-P reload kits.

Forward seal disk shown in liner.

A small percentage of customers using these 54mm reload kits have reported a "blister" forming on the exterior of the forward end of the motor case. The blister is caused by excessive heating due to a small amount of hot gas passing between the case and liner during motor operation. In addition to weakening the casing, the blister may interfere with the proper fit of the case in the rocket's motor mount tube.

In the past, AeroTech has implemented the use of similar forward seal disks with its longer 29mm, 38mm and 75mm RMS motors. The seal disk is a narrow aluminum ring that seals to the inside of the phenolic liner with a circumferential o-ring. The motor's forward o-ring seals against the forward seal disk when the motor closures are tightened. With the use of the seal disk, the liner o-ring and phenolic forward insulator are no longer required and are not included with the new reload kits.

The 54mm forward seal disk is available from AeroTech at a price of $14.99 suggested retail. Three seal disk o-rings will be included with each disk for use with older reloads. Updated assembly drawings and instructions for the affected reloads are now available for download in PDF format from the Resource Library on the AeroTech website at http://www.aerotech-rocketry.com/. 

NOTE: This seal disk is NOT the same as the disposable 54mm seal disk included with the K250W-P/L LMS™ motor kit.

AeroTech Consumer Aerospace is a division of RCS Rocket Motor Components, Inc., Cedar City, UT.