Air Breaks

[Zosma Procyon]

I use A.I.R.B.R.A.K.E.S. on most of my space vehicles to increase their deceleration on reentry. Normally, i have them opening forward, into the wind. This invariably results in them overheating, and if I wasn't a habitual user of the "ignore max temperature" cheat, they'd in variably burn off my ships. I don't do air craft. Would the air breaks function more effectively if I rotated them 180 degrees, so they presented their topside to the wind?

 

Clarification: I use them on capsules, although "capsule" is a little over generous for my current generation of vehicles. A more accurate description is cargo containers with rover seats in them. Saves a lot of weight and space. This is one of my most recent vehicles. It is a personnel return craft, picking up Kerbals her were posted to my space stations in orbit of Eve and Gilly. Notice the orientation of the air breaks. This particular vehicle isn't going to bother slowing down into a Kerbin capture orbit. I'm just going to slam it into the atmosphere and slow it that way.

Edited April 8, 2016 by Zosma Procyon
Clarification

[Foxster]

No, makes no difference, they work the same way either way around. 

I'm guessing this is Kerbin and you are coming in from a high Ap, possibly hyperbolic, orbit? If so, one way is to reduce your speed before hitting the atmosphere by making low orbit first. Would be unusual to burn air brakes up from low orbit re-entry unless you come in very steep. 

The best workaround is to know that you can occlude the airbrakes from temp but not drag. In other words, if you can get the airbrakes completely behind the area of parts in front when deployed then they will still work but won't overheat.

Undeployed (rotate 180° when placing) and deployed...

 

Edited April 8, 2016 by Foxster

[DunaRocketeer]

If it's a spaceplane you are using, getting your center of mass/center of lift in the right place at End of Mission (so that you can maintain a high angle of attack) will slow you down better than airbrakes.

Foxter, I'm sure that vehicle works as you describe, but why would you make something that clips so badly once the brakes are deployed?

[Foxster]

10 minutes ago, DunaRocketeer said:

If it's a spaceplane you are using, getting your center of mass/center of lift in the right place at End of Mission (so that you can maintain a high angle of attack) will slow you down better than airbrakes.

Foxter, I'm sure that vehicle works as you describe, but why would you make something that clips so badly once the brakes are deployed?

It wasn't a very good example, was done quickly. You can make this work without the clipping, depends on the type and design of the craft how best to do that. 

[Xyphos]

I don't bother with AIRBRAKES, I get better results by shoving things into a cargo bay and opening the bay doors during re-entry.

[FancyMouse]

It's more of a right tool for the right thing. Airbrakes is for the speed range between drogue chutes and heat shields. If it overheats, most likely airbrakes shouldn't be deployed and heatshield should do its job first.

[Red Iron Crown]

Gameplay question moved to Gameplay Questions. 

[Empress Neptune]

I use control surfaces instead of the airbrake part on my planes. It saves a little bit of weight and the control surfaces don't produce the ridiculous amount of drag that airbrakes do deep in the atmosphere. I've crashed planes just by deploying airbrakes.

The really high drag is what makes airbrakes useful for reetrny, but they won't help much if they blow up (though getting some deceleration and then losing parts in a "controlled" manner is a valid KSP method of doing things). You could try using Big S controls in place of the airbrakes. They generate decent drag and have better heat resistance.

 

3 hours ago, DunaRocketeer said:

If it's a spaceplane you are using, getting your center of mass/center of lift in the right place at End of Mission (so that you can maintain a high angle of attack) will slow you down better than airbrakes.

You can do both. Place airbrakes on the sides of your plane and angle them to match the angle of your reentry.

[max_creative]

Air brakes are good for generating drag to slow down. Anything bigger than an mk1-2 capsule that I intend to reenter I put some airbrakes on. Although they do do overheat and turn into airbreaks sometimes.

[MaxxQ]

Meh... I use airbrakes on some of my craft (non-spaceplane), and I toggle them through action groups.  I usually set them turned 180* at the base of an adapter.  This way, when stowed, they are out of the airflow, but when open, they provide drag.  On re-entry, if they start to overheat, I just toggle them closed for a few seconds.  They cool down, then toggle them open again.  Usually no more than 4-5 cycles of this before the craft has slowed down enough to leave them open.

[KocLobster]

Your airbrakes are always overheating and exploding because they are not meant for reentry.

[Foxster]

6 hours ago, KocLobster said:

Your airbrakes are always overheating and exploding because they are not meant for reentry.

Says who?

[Red Iron Crown]

10 hours ago, Foxster said:

Says who?

Says their low heat tolerance.

[Foxster]

Maybe but I always use them on almost anything of any size that needs de-orbiting. 

[swjr-swis]

On 4/8/2016 at 0:42 PM, DunaRocketeer said:

Foxter, I'm sure that vehicle works as you describe, but why would you make something that clips so badly once the brakes are deployed?

Because in KSP, it pays to use KSP engineering (as opposed to Real Life engineering). Use the tools and capabilities you have to deal with the problems and limitations you have; there is no point in trying to use the actual tools and capabilities you have to solve imaginary problems and/or limitations (tip: Real Life is imaginary in KSP ).

[KocLobster]

@Foxster

 

On 4/8/2016 at 7:47 AM, Snark said:

Your airbrakes are burning off because they aren't supposed to be used for reentry.  They're sticking out beyond the heatshield, and they have a low temperature tolerance.  It's not what they're for.  So don't use them for reentry, or at least, if you have them, don't use them until you're done with the hot part of reentry.

 

From this thread:

 

I was just taking what Snark said in another thread; personally, I can't attest one way or the other if airbrakes work that well in the manner described.

Edited April 11, 2016 by KocLobster

[Warzouz]

14 hours ago, Red Iron Crown said:

Says their low heat tolerance.

Says their lowered heat tolerance (since 1.0.5)