Thrustcurve Open Thread

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dhbarr

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OK, on the desktop browser you should be able to search for a range of diameters as well as either single or a range of average and maximum thrust.
Maximum thrust also shows up in the search results if there's space.
Really great stuff, love this resource.
 

smstachwick

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Hey!

I’m loving the new features on the site. I did notice a few things that might merit some investigation or updating though.

1.). The Contrail G300 has its total impulse listed at 161 N-s, peeking out of the G range and into the low end of H territory. The thrust curve in OpenRocket shows it closer to 100 N-sec. Could this have been a result of confusion with the Contrail H hybrids?

2.). It appears that the Aerotech I40 has gone out of production, according to the Master Motor Matrix dated 8/24/2021. R.A.T.T. also no longer appears to be producing hardware or reloads, according to their website. Some portions of the HyperTek website have not been updated in 20 years, with MSRPs replaced by an instruction to call the dealer. Not sure if they’re OOP but I’ve got a hunch they’d be hard to find.
 

JohnCoker

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1.). The Contrail G300 has its total impulse listed at 161 N-s, peeking out of the G range and into the low end of H territory. The thrust curve in OpenRocket shows it closer to 100 N-sec. Could this have been a result of confusion with the Contrail H hybrids?
Yeah, those could be bad data files. If you have a good one, please submit it and I will delete the other ones.

2.). It appears that the Aerotech I40 has gone out of production, according to the Master Motor Matrix dated 8/24/2021. R.A.T.T. also no longer appears to be producing hardware or reloads, according to their website. Some portions of the HyperTek website have not been updated in 20 years, with MSRPs replaced by an instruction to call the dealer. Not sure if they’re OOP but I’ve got a hunch they’d be hard to find.
I marked the AT 140 as OOP.

I'm not sure about HyperTek either; my feeling is that they are defunct, but at least for a while CTI was supporting them to some extent.
 

mikec

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1.). The Contrail G300 has its total impulse listed at 161 N-s, peeking out of the G range and into the low end of H territory. The thrust curve in OpenRocket shows it closer to 100 N-sec.
The TMT cert document https://contrailrockets.com/TMTPapers/G300.pdf says 100 N-s but gives a thrust curve that looks nothing much like the one on thrustcurve, so certainly something is confused.
 

JohnCoker

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The TMT cert document https://contrailrockets.com/TMTPapers/G300.pdf says 100 N-s but gives a thrust curve that looks nothing much like the one on thrustcurve, so certainly something is confused.
Thanks. I updated the info on the site to match that document and also uploaded it. (Where I have them, you can also download the certification letters on the motor pages.)

I agree that those simulator files don't look right.
 

Neutron95

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If you just want the thrust curves, the "combine motors" function at https://www.rocketreviews.com/combine-motors.html does this.
This is a great tool, but I really wish that Thrustcurve could implement something similar, since the EMRR database is a bit out of date, and it's also a bit of a pain to find motors in the list.

2.). It appears that the Aerotech I40 has gone out of production, according to the Master Motor Matrix dated 8/24/2021. R.A.T.T. also no longer appears to be producing hardware or reloads, according to their website. Some portions of the HyperTek website have not been updated in 20 years, with MSRPs replaced by an instruction to call the dealer. Not sure if they’re OOP but I’ve got a hunch they’d be hard to find.
The I40 was relatively recently certified, and should go on sale sometime early this year.
 

JohnCoker

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This is a great tool, but I really wish that Thrustcurve could implement something similar, since the EMRR database is a bit out of date, and it's also a bit of a pain to find motors in the list.
That's an interesting idea. Does it produce a RASP file as a result or just a thrust curve graph?

The I40 was relatively recently certified, and should go on sale sometime early this year.
Updated the motor back.
 

jqavins

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I didn't know about this EMRR feature until I read of it here, so I went and tried it out.
That's an interesting idea. Does it produce a RASP file as a result or just a thrust curve graph?
The problem for me is that it produces a RASP file and not a graph. I don't need a RASP file, since I can just load the cluster configuration in RS or OR; it's the graph I want.
 

mikec

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I didn't know about this EMRR feature until I read of it here, so I went and tried it out.The problem for me is that it produces a RASP file and not a graph.
It produces a RASP file and a thrust curve graph. Presumably you want an altitude simulation?

I guess thrustcurve could do this, but it would have to have a specific interface to do it.
 

jqavins

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OK, I'll have to try again. When I picked a motor configuration (1×D12 + 2×A10) it gave me total impulse, average thrust, and a RASP file; no picture.

When I want a detailed simuation, I'd have a rocket design (RS or OR) to simulate, with the propper cluster or mounts. So I'd load the engines and go. I see no need of a combined RASP file. What I'd like, and I may be asking for something that's more trouble than it's worth, is a graph for combinations that I'm contemplating even before the rocket is designed.

Also, since ThrustCurve is handier than RS and OR at the launch site, it'd be nice to do the that level of simulation using the combined thrust data. But still I don't see any situation in which the combimed RASP file would be useful.
 

Neutron95

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OK, I'll have to try again. When I picked a motor configuration (1×D12 + 2×A10) it gave me total impulse, average thrust, and a RASP file; no picture.

When I want a detailed simuation, I'd have a rocket design (RS or OR) to simulate, with the propper cluster or mounts. So I'd load the engines and go. I see no need of a combined RASP file. What I'd like, and I may be asking for something that's more trouble than it's worth, is a graph for combinations that I'm contemplating even before the rocket is designed.

Also, since ThrustCurve is handier than RS and OR at the launch site, it'd be nice to do the that level of simulation using the combined thrust data. But still I don't see any situation in which the combimed RASP file would be useful.
I mostly use the combiner in late night Discord voice chats when the conversation turns to rather silly topics.

The Rasp file output is nice for when I want to simulate a rough design quickly. Like when my friends and I wondered how many I1299s could fit into a 20" tube, and how the resulting rocket would perform.
 
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