LOL, Absolutely!!
Why rail/rod angle is important...
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LOL, Absolutely!!
ActingLikeAKid
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Taking this away from RSO/Safety issues for a sec...
I discovered this in OpenRocket:
I have a large HPR rocket that's overstable (something like 3 calibers with an I in it, I think). Haven't launched it yet, but on a top-of-the-range I, it simmed to something like 4900 feet. I know that it will weathercock in a bit of wind. With light wind, if I angled the rod around 2 degrees downwind, it weathercocks such that it (in theory) comes right back to the pad as the drift under chute negates the weathercocking. Here's the weird part: It goes higher. Launching slightly with the wind, it simmed to about 5300 feet.
I discovered this in OpenRocket:
I have a large HPR rocket that's overstable (something like 3 calibers with an I in it, I think). Haven't launched it yet, but on a top-of-the-range I, it simmed to something like 4900 feet. I know that it will weathercock in a bit of wind. With light wind, if I angled the rod around 2 degrees downwind, it weathercocks such that it (in theory) comes right back to the pad as the drift under chute negates the weathercocking. Here's the weird part: It goes higher. Launching slightly with the wind, it simmed to about 5300 feet.
LithosphereRocketry
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Yeah, I would think it might... The rocket weathercocks the most right off the pad. This way its initial swerve puts it vertical rather than upwind, after which it speeds up a bit and the wind matters less. I'm guessing the best scenario would be the one where the rocket hits apogee directly above the launch pad.
Good luck with recovery though...
rharshberger
Well-Known Member
That is correct, the angled launch rod will allow the rocket to weathercock back to vertical not depart vertical like a vertical launch rod would allow.
Edit: weathercocking with the angled launch rod is still possible, try increasing the angle and see how much actually will give a vertical flight.
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A couple things:
No Rockety is to fly in breezes higher the 20mph period. If this rocket was launched in higher "gusts" it is in violation of the Safety Code.
Second: It is now strongly suggested that all Rods and Rails be tilted 5degrees AWAY from the Flight line regardless of ambient wind direction. This simple requirement all be eliminates these "Weathercocking" incidents. Does increase some recovery walks but is better than poking holes in our vendor trailers.
No Rockety is to fly in breezes higher the 20mph period. If this rocket was launched in higher "gusts" it is in violation of the Safety Code.
Second: It is now strongly suggested that all Rods and Rails be tilted 5degrees AWAY from the Flight line regardless of ambient wind direction. This simple requirement all be eliminates these "Weathercocking" incidents. Does increase some recovery walks but is better than poking holes in our vendor trailers.
Sabrina
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That's kinda cool
that you learned this from playing around on a Sim program.I learned the same thing reading 'The Handbook of Model Rocketry" by G. Harry Stein. That book has a pretty good explanation about how rockets fly in the wind.
BDB
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That is really cool. I learned something today.
Sabrina
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I just want to make sure I understand the safety code. If a rocket is launched "in" a gust > 20mph its in violation of the safety code but if its launched between the gusts its not in violation?
