Fairings

[-RanZ-]

I seen a thread last week that said vehicle mass does not go down when fairings are ejected... has that been fixed? When you eject the fairings does the weight go with them? I tried searching for the thread but I could not find it.

[Rokmonkey]

Yes, the mass goes down when ejecting fairings now. I've watched the mass vanish in Kerbal Engineer myself when ejecting.

[FlipNascar]

Or you can test them yourself... And now for a more helpful answer: Yes. When you deploy the fairings your vessel's weight will go down. And thus, your delta-V will increase.

Edit: /Ninja'd

[-RanZ-]

I would and normally do test things test things myself but I am away for a couple days and was curious.

Did they fix the fact that a 1.25m part could shield a 3.75m part from drag? I seen something in patch notes regarding occlusion so assuming they did

Edited May 4, 2015 by -RanZ-

[severedsolo]

Which leads to another question... at what height do the fairings stop helping? Or to put it another way, what's the best height to jettison your fairings?

I tend to jettison just as my AP reaches it's target, but I know that isn't very efficient.

[Rokmonkey]

I eject my fairings in the 50km region. It depends on what my payload looks like, if there is some pointing things in there sticking out. eg. accidentally deployed solar panels, I wait until closer to 60km. This is subject to change if it's still in my main booster stage or the ascent stage. If it's the former, I don't bother too much, if it's the latter, I dump that fairing as soon as I feel brave enough.

[Juicy]

Which leads to another question... at what height do the fairings stop helping? Or to put it another way, what's the best height to jettison your fairings?

I tend to jettison just as my AP reaches it's target, but I know that isn't very efficient.

Short answer: once you leave the atmosphere.

Long answer: depending on whether the mass of the fairing is less than the drag caused by whatever it's covering, slightly below leaving the atmosphere, provided the contents of the faring do not overheat. Logically, it's also safer not to jettison farings while accellerating, since you might fly into the debris.