TMT Combined motor list

Section 8.3 of the National Fire Protection Association document 1125 “Code for the Manufacture of Model Rocket and High-Power Rocket Motors” reads as follows:  Listing of Certified High-Power Rocket Motors and Motor-Reloading Kits.  The authority having jurisdiction shall maintain a current and complete list of all those high-power rocket motors and motor-reloading kit types that are certified as complying with the standards and requirements detailed in Sections 8.1 and 8.2 and shall make copies of this list available to citizens and public safety officials who request it.

Well, that’s pretty clear, except for a certain fuzziness about exactly what the term “authority having jurisdiction” (AHJ) actually means when it comes to the activities of the Tripoli Motor Testing Committee.  However, that is of no consequence in this case.   Whoever they are, they cannot “maintain and make available” such a list unless somebody actually produces that list, and edits and curates it for accuracy and currency. 

Which is where I come in.  I assembled all the sources of information about hobby rocket motors [you will quickly see that I did not limit myself to high-power rocket motors] and began to co-list and cross-check those sources.  The two most encyclopedic references are the “Combined CAR/NAR/TRA Certified Rocket Motors List”, published by the NAR S&T Committee every six months or so.   This is abbreviated CML in the enclosed EXCEL file.  The other synoptic reference is John Coker’s website  www.thrustcurve.org   .  This source is abbreviated TC.  They  are not completely overlapping.  The big advantage of John Coker’s effort is the good-faith effort to determine which motors are currently in production, and which motors are not currently commercially available.

In addition, the manufacturers publish catalogues that contain valuable information about current availability, and their own evaluation of performance figures.   Finally, the actual certification letters themselves are available in several locations.   When I inherited the chair of TMT from Paul Holmes in 2016, he passed on a fabulous archive of old test data and certification letter copies.  The NAR website and the Aerotech website are good sources of electronic copies of certification letters.

This project will necessarily need to be edited and updated many times in the future.   If you have documentary evidence that expands or emends this data summation, please let me know about it using the link below.

Some details:  OOP motors are NOT “de-certified”.  You may continue to use them until supplies are exhausted.   In the far right columns of the EXCEL file I have done some calculations of delivered Isp (Isp*) based on published total impulse and propellant mass figures.   This is a good way to spot aberrations and deviations in the published data for those parameters.  Watch for the outliers!

Should you have questions or wish to submit an update to this please you may contact me here.

 Alan Whitmore

Chair, TMT