Co-leader of the LRP
stability is overrated
I know you can get that information in Rocksim, but can you get information on how far a rocket will drift in OpenRocket? If so, please let me know how to do it. Thanks!
Can you get info on how far a rocket will drift in OpenRocket?
- Thread starter Co-leader of the LRP
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You need to install the multilevel wind addon for OpenRocket from
https://github.com/rocketsam2016/MultiLevelWind/releases/tag/latest
You then use the multilevel wind data from the aviation met office to fill in the wind profile in OR.
Follow the instructions here
https://www.rocketryforum.com/threa...peed-direction-at-different-altitudes.140619/
All the best.
https://github.com/rocketsam2016/MultiLevelWind/releases/tag/latest
You then use the multilevel wind data from the aviation met office to fill in the wind profile in OR.
Follow the instructions here
https://www.rocketryforum.com/threa...peed-direction-at-different-altitudes.140619/
All the best.
Co-leader of the LRP
stability is overrated
If you just want to get a very rough idea, then put some wind into the launch conditions, and then when simulating plot the distance East of Launch and North of Launch, or you can plot distance and bearing.
Co-leader of the LRP
stability is overrated
But what I'm asking is asking is how do you do that. (Like a step by step thing, I'm terrible at computer things)
Ok. I’m away from home and not at my PC at the moment, and won’t be until Sunday PM. So I can’t give you step-by-step instructions to explain the process until then. I’m currently on an iPad that doesn’t have OpenRocket. Hopefully, someone else can do that for you before then.
There are probably other ways but this is what I do:
On flight simulations tab, double click on the simulation of concern & you should see this window open:
From that window, you can adjust your wind speed & launch angle. You can also adjust your wind direction. Once you pick a wind speed/angle, hit "simulate & Plot".
Then you can select "ground track" from preset plot configurations. From this menu, you can really customize the plot to meet your needs.
After you select "plot", you will get the following plot of the ground track. Hope this helps.
On flight simulations tab, double click on the simulation of concern & you should see this window open:
From that window, you can adjust your wind speed & launch angle. You can also adjust your wind direction. Once you pick a wind speed/angle, hit "simulate & Plot".
Then you can select "ground track" from preset plot configurations. From this menu, you can really customize the plot to meet your needs.
After you select "plot", you will get the following plot of the ground track. Hope this helps.
Keisling
Licensed Practical Rocket Surgeon
I use the same method that Tim posted. It's "ballpark" accurate but can be improved a lot by adjusting your drogue and main parachutes in OR to accurately reflect the actual descent rate of the rocket.
I just use flight side profile plot view. OR will even plot drift without a parachute, but its tendency to model it as a glider may be exaggerated. I've seen the drift with almost no wind come up as twice the altitude, and even seen it predict a loop!
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I do it the same way as timbucktoo and Keisling. It's ballpark accurate enough every time that I've used it.
This is good stuff, and I wish I'd known how to do that back in the days when I got "launch fever" quite a bit. Nothing like real data ti slap you in the face and sober you up a little.
However, should you find yourself apart from OR and need a "quick and dirty" method, try this.
Go here. Put in your rocket weight and chute size (remember that descent weight is after motor burnout and is less than the launch weight).
Get a descent time. In the worst case scenario, assume the rocket goes straight up, then gets blown as it descends.
Take the windspeed and multiply by the descent time (making sure the units match), that will give you your worst case drift distance. In real life, if the rocket is drifting due to wind, it will also have weather-cocked into the wind a bit, which reduces your drift distance.
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As an example, I used a 2# descent weight and a 28" hexagonal chute, and an expected apogee of 1200'. I get a descent time of 56 seconds.
Assuming a windspeed of 7 mph, which equates to 10.4 fps, then 10.4 X 56 gives me a worst case drift distance of 582.4'.
However, should you find yourself apart from OR and need a "quick and dirty" method, try this.
Go here. Put in your rocket weight and chute size (remember that descent weight is after motor burnout and is less than the launch weight).
Get a descent time. In the worst case scenario, assume the rocket goes straight up, then gets blown as it descends.
Take the windspeed and multiply by the descent time (making sure the units match), that will give you your worst case drift distance. In real life, if the rocket is drifting due to wind, it will also have weather-cocked into the wind a bit, which reduces your drift distance.
------
As an example, I used a 2# descent weight and a 28" hexagonal chute, and an expected apogee of 1200'. I get a descent time of 56 seconds.
Assuming a windspeed of 7 mph, which equates to 10.4 fps, then 10.4 X 56 gives me a worst case drift distance of 582.4'.
What Tim has described above is what I’d hoped to tell you above, but I wasn’t in front of my PC at the time. That will give you a ball park position, but if you’re going to any significant altitude, then you will need the multilevel wind addon to get a better estimate.
Alternatively, you could use the method described above, but use an averaged wind speed and direction from the multilevel wind forecast from the meteorological office or, perhaps, the Windy app.
Alternatively, you could use the method described above, but use an averaged wind speed and direction from the multilevel wind forecast from the meteorological office or, perhaps, the Windy app.
