Author Archives: JVDB

HTPB test batches

Awaiting some final ingredients I started to characterize the old-stock HTPB. I expect the HTPB I have is similar to R45HTLO so an EW of 1190 is used in the curative calculations. Small 50gr batches (measured to a hundreds of a gram) were made to evaluate the different Cure Indexes 0.9 – 1.3. The curative

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GIGA 86mm – KILO 12G CATO Final thoughts

Final thoughts on the CATO / overpressurization of the KILO 12G KNSB motor at the LRE 2017 launch: The motor had a very conservative port-to-throat area ratio of 1.5 to prevent velocity based erosive burning. This resulted in a higher than necessary,  Knaverage of 700 and thus higher Maximum Expected Operating Pressure (MEOP). Mass flux based erosive burning. Little has been described about

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LRE 2017 – Launch

“We had a bad day”. This pretty much sums up our launch day at LRE 2017. First LD’s CHIRON 3 rocket overpressurized in a spectacular way, taking out the upper 2/3rd of the launch rail. A makeshift launch rail was made and the GIGA was launched from the remaining 2,5m lower section. The GIGA rocket suffered the

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GIGA 86mm – Nose cone avionics

The nose cone avionics arrangement went through quite a few iterations as it was more or less designed around the 4000mAh battery. However it proved to be quite a challenge mounting the battery on the centerline of the rocket / nose cone and still being able to fit the other components. Although the 86mm 5:1

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GIGA 86mm – fin retention

The GIGA rocket has been designed as a true minimum diameter rocket with fin brackets mounted directly onto the casing. This is not a particular KISS approach but rather a result from the “sustainer ready” requirement. Alternatives considered were: Welded aluminium fincan. However due to the lack of availability of matching off-the-shelf materials (it is

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