Launch Lugs: 1 or 2

[lakeroadster]

On my scratch build lifting rocket I am seeking advice on launch lug location.

Since it has 3 motors above the CG and CP it may arc in flight if all three of the upper cluster motors don't fire.

I currently have it designed with (2) launch lugs as shown below....

Would it be better to have one lug mounted at the CG? My thought is if it does want to arc over at launch, that bottom lug may get hung up on the 1/4" launch rod.

Or maybe keep the upper lug, and move the lower lug up to the CG?

Thanks in advance for your thoughts / comments.

 

[lakeroadster]

I hear crickets....

 

[prfesser]

I guess I'd do railbuttons on anything other than a really small rocket, but that's just me. Seen one too many rods whip in the wind at the wrong instant. I'll need to put some extensions to add railbuttons to my Interceptor and Interceptor G...but railbuttons they will be.

Of course, if you have a place very nearby to fly, and your own launch system, it's moot. Do what you like best. I'm now thrilled that the nearest place to launch is about an hour and twenty minutes away. Was used to driving 3.5 hours or 7 hours, depending...

Best -- Terry

 

[mbeels]

How long is your launch rod? The two lugs becomes one when the top one leaves. It's a pretty tall rocket, it looks like the distance from the bottom of the rocket to the top is more than 36"? I think the best would be to keep the top where it is, for stability in the very first moments of acceleration, but then move the bottom up to the CG.

 

[lakeroadster]

How long is your launch rod? The two lugs becomes one when the top one leaves. It's a pretty tall rocket, it looks like the distance from the bottom of the rocket to the top is more than 36"? I think the best would be to keep the top where it is, for stability in the very first moments of acceleration, but then move the bottom up to the CG.

I haven't bought the launch rod yet, lugs are sized for a 1/4" diameter rod.

That's a great idea on moving the lower lug up to the CG.. Thanks for the suggestion.