Open Rocket confusion on length

CalebJ

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I'm experimenting with a 2 stage idea in OR (beta 22.02_5) and ran into a weird quirk. Nose cone length is set at 15cm, 73cm of combined body tube length, and another 3cm for a boat tail transition at the end. But the view of the rocket indicates a length of 203cm and the view scaling behaves as if it's that length. Is there a phantom part causing this? ORK file is attached.
 

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neil_w

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1000 quatloos to you for posting the ORK file.

It appears to be a bug in the way the boosters are being handled. My apologies. We'll get this fixed in the next release.

Just to be clear: it is your intention to have 4 drop-away side boosters in the first stage?
 

CalebJ

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Awesome, thanks!


I don't want them to drop away. The idea was for them to be permanently attached to the first stage and deploy streamers to facilitate spotting and keep the descent rate manageable. Should I reconfigure them as pods rather than boosters to reflect that correctly?
* Edit - just realized I'd forgotten to set them to never separate. Fixed!

Side question... If I just simulate the sustainer, the ground hit velocity makes sense given the 6 second delay on the selected sustainer motor and a selection of parachute deployment at first ejection charge of the stage. However, if the whole system is simulated together, ground hit velocity goes through the roof unless I select apogee deployment for the sustainer parachute. Any idea what's going on there?
 
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neil_w

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I don't want them to drop away. The idea was for them to be permanently attached to the first stage and deploy streamers to facilitate spotting and keep the descent rate manageable. Should I reconfigure them as pods rather than boosters to reflect that correctly?
* Edit - just realized I'd forgotten to set them to never separate. Fixed!
I believe that if they're not going to separate then they're exactly like pods. Suggest trying this with pods and see if it fixes the length calculations.

We've had some internal discussion about whether boosters and pods should even be two separate component types... they're identical except boosters can separate.
Side question... If I just simulate the sustainer, the ground hit velocity makes sense given the 6 second delay on the selected sustainer motor and a selection of parachute deployment at first ejection charge of the stage. However, if the whole system is simulated together, ground hit velocity goes through the roof unless I select apogee deployment for the sustainer parachute. Any idea what's going on there?
Ya got me on this one. Calling in reinforcements... @JoePfeiffer @H. Craig Miller @SiboVG.

By the way it seems that changing to pods does *not* fix the length issue. Weird, I thought we had addressed all this stuff by now.
 

JoePfeiffer

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Definitely an interesting (weird) bug which is triggered by putting a mass object inside of a body tube on a booster with a booster copy greater than 2, or by putting a mass object inside of a body tube on a pod with a pod copy greater than 2.

Follow Issue #1849.
Seriously? This is hands down the screwiest OR bug I've ever heard of. I don't know how that can even be possible! Wow.
 
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