Launch Pad Angles

[Dbarrm]

Ok being new here I wasent sure where to put this. I have been doing lots and lots of reading here and looking at a lot of wonderfull pictures. What I have noticed is that in a lot of them the launch pad is at an angel. Is this to compensate for wind? I don’t ever remember launching any of my rockets in the past at an angle.

Dan Learning to ride all over again.

 

[qMaxx]

Yep...that's exactly what the angle is for - to compensate for wind conditions. Another reason I've seen once or twice is for altitude. By angling WITH the wind, the rocket will go higher than it would against the wind...good for altitude competitions, but it means a long walk for recovery.

 

[Karl]

Yes sometimes rockets are angled into the wind if it's fast. This means that when the recovery system delpoys , it blows more or less to to place it started from . And sometimes people angle it so that it doesn't go as high as it should , but most of the time you should swap to a weaker motor (ie: C6-5 swap to B6-4), but it might just be that the rocket can not be flown on a B6-4 due to it's flight profile.
-Karl

 

[Dbarrm]

Thanks, thats what I thought. The more I read the more I see I have to learn. Thank god for the Glossary.

Dan

 

[graylensman]

Originally posted by Dbarrm
Dan Learning to ride all over again.

Welcome to TRF and welcome back to the hobby (I guess from your post).

Keep in mind NAR safety regs put a 30 degree limit on launcher angles.

 

[Dbarrm]

Thanks for the info.

Dan

 

[Steve]

I have been having the hardest time lately getting the right angle on my launch rod. I have no idea why, but it seems like for years I had a pretty good knack for judging the wind and estimating the landing zone for just about any (low-power) rocket I would launch. I was kinda proud of how close I could get each bird to land to where I wanted it. But lately I seem to have lost my touch. Is it possible that the last dozen or so rockets I have been flying are more prone to weathercocking (Berthas, Big Daddy, etc.) and as such require a different approach? Either way, it's become a welcome challenge to try and land within walking distance of the pad.

S..

 

[Silverleaf]

Rockets with larger fin surface are more susceptible to the wind on launch. There really isn't any perfect method to determine exact angle of attack, although I tend not to launch larger fin designed birds on windy days - above 10 mph.

The rule of thumb that I use is 1.5 degrees of angle for every mph, but I have no clue why I use that number. Maybe Stines Book of Rocketry answers this query.

Dang, I need that book..*sniff*

 

[Johnnie]

for me, because fins are designed to stable the rockert for flight, they are also wind grabbers...when launched they will fly into the wind anyways...

I zero angle when ever possible...straight up. Angle should be used for spot landing, and even that is a gamble.

 

[Steve]

Originally posted by Johnnierkt
I zero angle when ever possible...straight up. Angle should be used for spot landing, and even that is a gamble.

I think that's what I need to do more often. I always hesitate though, for fear of the rocket drifting downwind - but I should take into consideration your point about the fins causing it to drift into the wind anyways. Old habits, I guess.

S..