About this Site
This site debuted in 1998 as a repository for simulator files generated from actual motor firing data provided by the Tripoli Rocketry Association (TRA). At that time, the goal was to provide accurate simulator files converted directly from the data obtained at the motor test stand. I was able to get data for most TRA-certified motors, but the National Association of Rocketry (NAR) was not willing to make their data available.
Subsequently, TRA stopped making data available and the site languished. There was still the original set of generated files, but it quickly became outdated as new motors were introduced and new motor manufacturers entered the market. As a stop-gap measure, I added a page to which people could contribute data from other sources (usually from the motor manufacturer).
I had thought repeatedly about changing the format of the site to being organized around the entire set of certified motors from all three organizations. (The Canadian Association of Rocketry (CAR) entered the certification business during that time as well.) Good intentions finally turned into action in 2006 when I started working on the first programmatic site (v2).
The new model turned the original site inside out. Instead of being driven by motors for which I have data, the list of motors is all the ones that have been certified, mostly from the NAR combined list. Additional information is pulled from the web sites of the three certification organizations to fill in the details.
With the master motor list set up, motor data files can be contributed by anyone who has them. The data is no longer as "authoritative," but at least whatever is floating around can be available in one place. Please help out the effort by contributing data files if you have any that are missing here.
In 2009, Mark Koelsch, who had been a major contributor of motor data, joined as editor of motor information. Mark passed away in 2018; we miss you!
In 2014, I started working on a smart phone app that would access the data on this site, providing search and the motor guide in your hand. Plus, the results could be saved locally for reference out at the launch site. The app was released for iOS and Android in early 2015, but incompatibilities between the the Cordova toolkit I was using and Google store policies broke the Android version.
But the site itself had become dated and was getting hard to maintain. I had been meaning to rework it to use a responsive layout, but instead I started rewriting it from scratch using modern web technologies in 2016. You are looking at "v3." The source code for the site is publicly available for those who are interested.
In 2020, the previous hosting provider for the JSP-based site went out of business and even though I hadn't finished the rewrite, I had to bring "v3" live and continue working on it. There is still a long list of things to-do.
I hope you enjoy this site and find the information and data useful,
John Coker
