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Max wind for launching with A and B engines

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LakeWobegonMN

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Hi guys,

I'm considering launching with my kids today for the first time...Alpha 3 with A engines, and Baby Bertha and Big Bertha with B engines.

Winds right now are only 7 mph. By the time we can get out there...and the ground dries up from an overnight rain...it looks like winds should be 10-12 mph. Is this a good or bad idea? If I look out for the next 10 days, each day seems to be like 14+. And really, we can only launch in weekends since we'll be using a school yard.

Thanks for any tips!! I'd rather wait and not lose a rocket. But, these are flying pretty low so maybe ok.
 

cbwho

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Despite the your login name, I take it you are not launching from MN as there is snow on the ground.

Windy conditions can cause 2 problems: weathercocking and drifting too far way.

Bigger venues help both. (E.g. frozen lakes)

For the drift, smaller engines and streamers work well. For weathercocking, bigger engines help.
 

Jeff Lassahn

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People do fly in 10-15mph winds, so if you're not seeing better weather in your future you can probably give it a try.

I'd suggest starting with the Alpha on an A engine, adjust the launch pad to point a few degrees upwind, and watch where it goes. Move the location of the pad and the launch rod angle based on how the first flight goes, and if it seems like things are going well and your rocket is landing somewhere reasonable you can try higher power flights.

Also, pay attention to how the wind feels during your countdown, if it feels like it's getting gusty or whatever it's always OK to scrub the launch at T-3 seconds and try again in five or ten minutes.
 

Zeus-cat

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The model rocketry safety code states that you can't launch in winds greater than 20 mph. Personally, I don't like launching when the winds get over 10 mph, but I will go up to 15 or so with bigger rockets.

A few, but not all considerations are the size of the fins on the rocket (bigger fins will result in more deflection when hit by the wind), how high the rocket will go, streamer or parachute, and how big the recovery area is. As the previous answers stated, start small and work your way up. A rule of thumb is that most rockets will go at least twice as high on a B motor that they do using an A motor.

Keep in mind that winds higher up are not the same as at the ground. They could be stronger or weaker and could even be blowing in a completely different direction.
 

LakeWobegonMN

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People do fly in 10-15mph winds, so if you're not seeing better weather in your future you can probably give it a try.

I'd suggest starting with the Alpha on an A engine, adjust the launch pad to point a few degrees upwind, and watch where it goes. Move the location of the pad and the launch rod angle based on how the first flight goes, and if it seems like things are going well and your rocket is landing somewhere reasonable you can try higher power flights.

Also, pay attention to how the wind feels during your countdown, if it feels like it's getting gusty or whatever it's always OK to scrub the launch at T-3 seconds and try again in five or ten minutes.
Thanks! We went for it and not even close to being an issue. Everything flew straight and landed pretty close to where we launched it. 6 launches, 6 recoveries!

Nothing went too high. The Alpha was flown only on A engines. The Big Bertha only on B...both very straight and stable flights. The Baby Bertha on a B went the highest, but still an easy recovery.
 

Jeff Lassahn

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Hope the kids had fun! You can do calculations and ask for advice, but there's no substitute for going out there and getting some real world experience. Sadly that eventually means you'll lose a rocket or two in order to find out you shouldn't have done that thing just now. But hopefully it doesn't happen too often...
 

LakeWobegonMN

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Hope the kids had fun! You can do calculations and ask for advice, but there's no substitute for going out there and getting some real world experience. Sadly that eventually means you'll lose a rocket or two in order to find out you shouldn't have done that thing just now. But hopefully it doesn't happen too often...
They sure did! Time to get more engines!
 

SCooke123

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Glad you had a good day - I bet the kids enjoyed it.....
 

LakeWobegonMN

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I just wanna say that everyone either helping me out or simply liking my posts added to the warmth in my heart from this first set of launches with my kids. I can tell this is a good community with a good bunch of people. Good fun, some STEM, and good memories are what it's all about. :)
 
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