TIL: Airbrake assist for booster separation.

[Psycho_zs]

I've come to an interesting technique while trying to solve two problems at once: guiding boosters away from the core and preventing them from disintegrating by flipping in aistream or crashing into each other behind (FAR + Stage Recovery).

An elegant solution: place two airbrakes near the bottom of the booster some 95-105 degrees from the core. Engage and hold brakes about 0.5-1 seconds before decoupling. Airbrakes will pull boosters back and slightly away from the rocket and each other, while also preventing them from flipping.

P.S. Mini airbrakes recommended!

[Vicomt]

It's a nice idea, but aren't you going to get some serious drag for that 0.5-1 second period? I'm not sure how much dv that would cost, but it's probably not insignificant, depending on the size/cost of your launcher.

[I_Killed_Jeb]

seems a bit overengineered to be honest

[Arsonik]

I mean, you could use them to help steer the rocket as well if it was a super duper heavy whackjovian size deal, as opposed to using winglets. That would reduce redundancy by having one system for two jobs. I kinda like it.

[strigon]

It's a nice idea, but aren't you going to get some serious drag for that 0.5-1 second period? I'm not sure how much dv that would cost, but it's probably not insignificant, depending on the size/cost of your launcher.

Not really; keep in mind how slow airbrakes are to deploy.

In my experience, large amounts of drag are only experience ~1 second into deployment. More than enough time to let go, unless you've got truly dismal reflexes.

[G'th]

You would probably find it easier to just use separation motors. Or, put your rocket into a spin as you jettison your boosters.

Using airbrakes, while neat, does add a bit more complication to a launch, especially if you have a rocket that causes the game to go yellow.

[T-Bouw]

I find that adding one of the smallest fins on each booster gets about the same thing done.

[Renegrade]

.....or just mount the decouplers high on the booster, and let the air resistance catch 'em and fling 'em away for you?

[Fearless Son]

Same with T-Bouw, inexpensive stationary stabilizing fins near the bottom of the boosters creates a very similar effect. Further, it lowers the center of drag which helps the craft from spinning out on ascent. As long as the boosters are mirrored across the hull, the fins create a symmetrical drag. But once they are decoupled, the drag on each booster is now asymmetrical, and it tilts them gently to the side as they fall away from the hull.

[xebx]

Use sepratron like the real rockets.

Note : sepratron are only usefull on powerfull rockets when ejecting booster in lower dense atmosphere area at mach 1-2.

In higher atmosphere aerodynamic effects are smaller and won't push the boosters back to the main rocket, you don't need the sep.

Same with smaller or low twr rockets, ejection force is enough or speed is too low.

[MalfunctionM1Ke]

seems a bit overengineered to be honest

There is no thing like overengineering in KSP

There is only "trying new things"

[Psycho_zs]

I have no special liking of fins, and yes, it is "trying new things"

I now use aribrakes on short-burn first stage boosters that kick the rocket up to 1 mach in the dense atmosphere. It also helps to counteract slanted nose cones which cause boosters to swing back and ram into each other.

[Fearless Son]

Use sepratron like the real rockets.

Note : sepratron are only usefull on powerfull rockets when ejecting booster in lower dense atmosphere area at mach 1-2.

In higher atmosphere aerodynamic effects are smaller and won't push the boosters back to the main rocket, you don't need the sep.

Same with smaller or low twr rockets, ejection force is enough or speed is too low.

You know, some aerodynamic nose-cones with built in Sepratron-scale SRBs would be a nice addition. Should allow that functionality without adding additional drag near the top of the rocket, and keep the total part count down.