install open rocket instead then. Its not really an "install".. it's just a free-standing java file.
https://openrocket.info/
Center of Pressure
- Thread starter SHH
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Help Support The Rocketry Forum:
https://openrocket.info/
Use this link to install OpenRocket 15.03... OpenRocket Installation
oh. was I wrong? I thought mine was just an "unzip and drop it where you want it" thing
You can do that as well, but many folks have Java compatibility problems, and the packaged installer Craig linked above solves many (most?) of them.
If you want to use the raw .jar file, you must have Java version 8, although problems can still arise.
It doesn't work for me (running linux), I get many pages of javax/script/ScriptEngineFactory errors and "Illegal reflective access operations".
Maxwelljets
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You need the correct JRE installation. IIRC it only works with JRE 8, and if you have any other versions of JRE it becomes a headache to get openrocket properly associated with only that one. I have an ancient Lenovo X61 that I keep around because it's a wacom tablet, and in order to get Openrocket installed on it with Lubuntu I ended up uninstalling everything java related but OpenJDK Java 8.
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1234 Pressure. Take your oddroc up for inspection. The club president is an aerospace engineer who likes to do Barrowmans with pencil and paper. All you have is mindsim, nothing more than Peter Pan advice. Feel the Pressure! It is still Billy Joel to me! One viewing of the old video on an RCA XL 100 with a mechanical tuner and the CP becomes clear. Yes, I survived the Eighties.
Where is the gosh dern CP? Flying on 2 F15 0s plugged with epoxy, relying solely on drag seperation for deployment. Top men watching with interest at the research launch. PRESSURE!
We have Top Men working on it.
Put it in a really big warehouse.
Then you can figure the CP.
BDB
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I can't believe I missed this post! Did this this fly yet?
The cardboard cutout method should scale.
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See it more and more these days. especially with saucers and the rarity of commercial plugged motors. I have never seen one fail.OMG he plugged motors with epoxy, oh the humanity, I hope the rso had you flogged
Modifying an engine is against the safety codes, as we all know. Light sanding of the outside of a paper casing to help it fit is an accepted exception. Personally I think that plugging with epoxy should be another exception, and I know many agree.
If the plug fails, one's rocket is in jeopardy, but can someone say how it'd a safety issue?
If the plug fails, one's rocket is in jeopardy, but can someone say how it'd a safety issue?
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Wow. That guy was a martial artist, a rocketeer, and a jedi. I knew he was an impressive person, but Wow!
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Respectfully disagree, but only for rockets with very exaggerated body tubes, usually very long. On the cardboard cutout model the body tube affects the CP exactly the way the fins do, simply a matter of the area of total lateral surface area. Particularly for very long body tubes (beyond 30 - 1 length to diameter) the CP calculated by Cardboard Cutout (the balance point) is significantly forward of that calculated by Barrowman and typical software programs which are based on Barrowman. Because at or near 0 angle of attack, the body tube presents little aerodynamic force, its effect minimized/ largely disregarded in Barrowman. This is the principle that allows Back Slide rockets to work. Barrowman doesn't work when the angle of attach is significantly greater than 0. I don't know how far off you need to get.
