Anyone know of any other examples?

Water Rocket Booster to Estes C6-5 Second Stage

https://www.youtube.com/watch?v=Gj_1pfgsfOk

Two Stage Water Rocket with Estes Black Powder B6-4 Sustainer

https://www.youtube.com/watch?v=RAgefAzoP1A

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The other day I sat next to a woman who has a profound fear of flying. I wanted to comfort her, so I said, "Don't worry, we're not gonna' crash. Statistically, we got a better chance of being bitten by a shark." Then I showed her the scar on my elbow from a shark attack. I said, "I got this when my plane went down off of Florida." - Dennis Regan

Very interesting. I assume an automatic ignition the second the booster acceleration ceases?

Staging/air start function is included in a fair number of dual deploy altimeters and flight computers - used for clusters and staging. No reason I can think of why one wouldn’t work the way you described it with a water booster same as a “conventional” motor.

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John Scott B.

NAR #102949/L1