launch site conditions and rocket selection

[JohnCoker]

Still working on the new ThrustCurve.org, I added support for launch conditions (altitude and temperature) in the simulation code. I was thinking of adding launch conditions as a global preferences, but then I thought it might be more useful per-rocket or even each time the guide was run. I don't want too many options (that just makes things confusing), so I'm wondering if you tend to launch at the same place or multiple places and if multiple places do you launch different rockets in different places or all your rockets in a variety of places.

Note that I'm taking about significantly different conditions (thousands of feet altitude or cold vs hot temperatures). For example, the last two launches I attended were LUNAR (112ft altitude, 80&#8457 and AERO-PAC (3960ft altitude, 95&#8457. That makes a significant difference (about 7% difference in apogee for one rocket).

 

[markkoelsch]

John, I really like the current version. I worry that a simple and very effective tool may become too much, so to speak. Where do you draw the line?

Add temperature and altitude. What's next- wind speed and launch angle? Not saying you shouldn't do that, but it would complicate things a bunch. Then you are bordering on a full boat simulator ala OR, Rocsim, or Rasaero.

I am for features as long as it does not become over complicated to use, or too complicated to write and maintain for you.

 

[Wayco]

I'm with Mark on this, keep it simple. We fly at a lot of different locations, but I don't change my sim's for each one. If I have a rocket that might tickle the waiver, I will adjust conditions in OR, but Thrust curve is for picking motors that will fly the field.

 

[JohnCoker]

Sounds reasonable. I will continue to focus on the missing pieces that prevent me from making the new implementation live (admin pages and support for the API used by the phone app).

 

[GrouchoDuke]

FWIW, I've been cheating and modifying my Cd values to match the real altitudes I'm seeing at my local launch site. That doesn't let me look at variations between different motor at different launch sites, but it at least tells me the semi-close number I should see with the different motors at my home drome.

I think it'd be cool to have altitude & temp in there. A global setting that you can modify per motor guide query would be awesome. Like Wayco said though, it's pretty easy to use ThrustCurve to whittle down the motor choices then throw them in OpenRocket.

Thanks for the great site!

 

[Steve Shannon]

Our home field is 5,666'. The vast majority of my launches happen there. Once or twice a year I try to go somewhere else. Almost any place I go besides Colorado will be a couple thousand feet or more different, but will result in lower flights. What you now have works for me. Thanks! Wind direction isn't important because it changes at different altitudes. I don't expect ThrustCurve to do all that, but I would not say no.

 

[Incongruent]

If you do add the extra features, it might be better as a list of additional attributes, so if a more realistic simulation is desired, that's an option, but the quick and simple version that is used most can still be used.

 

[Buckeye]

I'm with Mark on this, keep it simple. We fly at a lot of different locations, but I don't change my sim's for each one. If I have a rocket that might tickle the waiver, I will adjust conditions in OR, but Thrust curve is for picking motors that will fly the field.

I agree. I say keep the Thrustcurve Motor Guide focused on thrust and motors.

 

[Zeus-cat]

Guys in my club occasionally use thrustcurve at our launches. Now I personally don't use it as my smart phone just ain't all that smart, but the other guys type data on their phones. The more stuff you have to type on a phone I think the less likely people would use it, or the more prone it is to typing errors. We use it for quick and dirty checks to make sure the proposed motor is a good choice for the rocket or that we will not exceed our waiver altitude. So keep it simple please.

 

[rstaff3]

I don't use Thrustcurve fo sims, but maybe keep a 'default' as the basic sim and then have an 'advanced' tab for those who what to twiddle with more parameters.

 

[Maxter]

I love the simple but, a "no Sparky" option would be nice.