"Deployed" control surfaces, what is it?

[kahlzun]

One of the changes I have noticed in 1.0.x is the inclusion of a "deployed" section under the menu for all control surfaces.

I have not been able to figure out what this option does, if anything.

Anyone able to help me out?

[TUKE]

I think the idea was so you can make flaps via action groups, well that's what i use them for anyways.

[kahlzun]

But what does it actually do? Mechanically, i mean?

[Alshain]

It's broken, or it was in 1.0.2. You can still create the flaps but the Deployed state resets on launch so it is meaningless. Ideally it should have been able to allow the control surfaces to be deployed when first launching because you typically take off with the flaps deployed.

The flaps are somewhat weak anyway. Unlike real flaps you only have all or nothing settings (most flaps have 4 settings) and in 1.0.2 (I haven't tried higher yet) they just weren't needed because you could get just about anything to glide at any speed. Normally flaps create lift and allow a plane to fly at slower speeds, good for getting off the runway and also getting back on it.

Edited June 24, 2015 by Alshain

[Hcube]

Basically, hit the brakes when in flight and the evelons will lower themselves just like flaps. Depending on your aircraft design it will not make you pitch and will slow you down a great deal. I like them for landings.

[TUKE]

I normally set mine up for button 1. They make landings slower and more controlled and lead to less brake orientated flip overs.

[Madrias]

I typically used them as flaps, occasionally as air brakes. Yeah, you can float things down to Kerbin ridiculously slowly, but sometimes shedding an additional 20 m/s is nice, ensuring that even if you screw up the landing, the cockpits survive.

Also tended to use them as flaps and airbrakes for my high-altitude rocket gliders. Launch myself up to 50,000 meters, dump my heavy fuel tank and rocket motor, and see how far I could glide. Flaps help increase lift (minimalistically, but it's there) to maintain slow cruise, and air brakes keep the glider from shedding parts as you descend (hopefully) with style and grace.

[Guest]

I don't use deployed elevons as flaps. I set them to "inverted" and use them as wing spoilers deployed with the 'brakes' button. Once I touch the runway, I'm staying on the runway.

[sal_vager]

It's not broken, in the editor it just lets you see which way they will deploy in flight allowing you to reverse them if needed, set them to an action group to actually use them as flaps.

[KerbMav]

I did not know this! Why?

[Red Iron Crown]

The flaps are somewhat weak anyway. Unlike real flaps you only have all or nothing settings (most flaps have 4 settings) and in 1.0.2 (I haven't tried higher yet) they just weren't needed because you could get just about anything to glide at any speed. Normally flaps create lift and allow a plane to fly at slower speeds, good for getting off the runway and also getting back on it.

A workaround for the single setting is to have multiple flaps and deploy them successively for increasing effect.

In stock aero I find they are mostly useful for reducing the required AoA for takeoff/landing, handy for long tailed designs.

[Alshain]

A workaround for the single setting is to have multiple flaps and deploy them successively for increasing effect.

In stock aero I find they are mostly useful for reducing the required AoA for takeoff/landing, handy for long tailed designs.

That isn't a workaround, they deploy to full as it is. You don't more than than full, you need 1/4 deployment and 1/2 deployment. Full deployment is just for landing, for takeoff you shouldn't need more than half deployment or it creates too much drag which is counter intuitive to takeoff.

[DancesWithSquirrels]

I like them as early career air brakes, deploy symmetrically on the trailing edge of the wings or tail surfaces tied to the 'Brake' action.

They are great for Shuttle style tail air brakes that way.

[Red Iron Crown]

What I mean is you can have, say, three pairs of control surfaces to use as flaps. You can deploy all three for full flap effect, two for intermediate flaps, and one for minimal flaps.

Certainly it is less useful than varying deployment on a single flap, but it can approximate variable deployment to some degree. (Pardon that awful pun.)

Edited June 24, 2015 by Red Iron Crown
Typo

[Captain Vlad]

I've had decent luck using them as additional drag resources during spaceplane reentry.

[ajburges]

I deploy flaps right before pitch-up for take off. That way, I do most the acceleration without the drag. Having that extra lift ahead of your CoM can greatly reduce pitch authority and AoA needed for take off. It can also be a handy boost to your landing glide slope.

Sadly, the only use I have for deploying pitch surfaces is to maximize trim for Kobra manuvers. (Unless I have canards)

If you use paired rudders, you could use deployment of those as a weak air brake.

[klesh]

Good tips fellas, I had no idea about this feature.

[Alshain]

What I mean is you can have, say, three pairs of control surfaces to use as flaps. You can deploy all three for full flap effect, two for intermediate flaps, and one for minimal flaps.

Certainly it is less useful than varying deployment on a single flap, but it can approximate variable deployment to some degree. (Pardon that awful pun.)

I don't understand this. That isn't full flaps, that is 3x full flaps. You are toggling between 1x, 2x, and 3x flaps. I'm looking for 1/2 and 1/4 (or really 1/3 and 2/3 would probably be more accurate)

Edited June 25, 2015 by Alshain

[Nothalogh]

I don't use deployed elevons as flaps. I set them to "inverted" and use them as wing spoilers deployed with the 'brakes' button. Once I touch the runway, I'm staying on the runway.

Yep, I use them as spoilers as well, especially on delta winged SSTOs as they cause some drag but also force a nose up attitude

[Red Iron Crown]

I don't understand this. That isn't full flaps, that is 3x full flaps. You are toggling between 1x, 2x, and 3x flaps. I'm looking for 1/2 and 1/4 (or really 1/3 and 2/3 would probably be more accurate)

Each flap adjusts the required AoA and lift characteristics of the craft and the effect is additive, so by using smaller control surfaces and engaging them successively you get a similar effect as a single larger flap with multiple degrees of deployment. It doesn't help with situations where you want a partially deployed single surface, but it can be useful for larger craft.

[xtoro]

Another tip: You can invert which way it deploys. So if you have large wings with 2 sets of control surfaces, invert one of the pairs. Now when you deploy them, one set goes up, the other goes down. This makes for good braking without affecting your pitch because they counter each other.