"recovery device opened while motor still burning"
(This is the same message I got when mixing D12-0s with E12-8s, which prompted me to create a D12-P file to simulate wadding and taping the top of a D12-0.) Since the fake motor is set not to ignite (for I don't want the mass lost in flight) and has no ejection charge, and since recovery is set for first ejection charge, I'm wondering if there is something I've missed in creating the motor files. I'll do some more tinkering later on. I have confirmed with rocket and motor mass plots that the mass stays as expected, dropping the mass of propellant in the actual motors during their burn but retaining the mass of the fake motor.
Since I've been testing this on a more complex design than is needed to demo the utility of the hack or diagnose the warning message, I'll try to upload a simpler example later on.
Thank you, Neil. If no one knew a simpler way to accomplish this, I had intended to submit a feature request to add configurable mass elements to the configurations created in the Motors & Configuration tab, but I didn't want to pile-on during the beta so was going to submit it after release. I've also been trying to learn the code so as to figure out how this could be added, but it's been very slow going so far.
This would go very well with issue
1053 to add chute release support, at least for my use of the chute release, where on some rockets I use it for larger motors but I don't with smaller motors. My other - main - use case is to change out nose weights to tune stability when flying different motors. But it would also be useful for cameras, trackers, etc., anything that may be on one flight but not the next.
I have been handling this either by overriding mass from one sim to the next - copying down the results so as to retain them when I revert to the original mass, or by keeping two (or more) separate ork files up to date with the same changes. The fake motors are an attempt to be able to manange these different flight configurations in a single file and without all the back and forth.
In the very long run, it would be ideal to be able to create and sim a more modular rocket in the same file, e.g., to fly with an avbay and and extra body tube in one configuration and not in another - or even to fly a sustainer with a booster in one configuration and on its own in another - but I realize that would be a much larger effort than variable mass elements would be (and I'm sure even variable mass elements won't be simple when all is said and done).