Spaceplane problems

[LittleItaly]

I finally got the nerve to exit my rocket comfort zone and am now learning how to do spaceplanes. At the moment, though, I am more focused on making just a simple jet, mainly something that I can fly from KSS to the secret runway and land. I designed a plane that can take off between 50 and 80 m/s and the ASAS I have installed helps with that initial bearing. However, my plane seems to always veer downwards as soon as I disable ASAS to make any kind of bearing change. Is it even possible to perfectly balance a plane? Currently, my CoM is ahead of and above my CoL. Is this the ideal configuration? Should I use more control surfaces? More lift surfaces? Any advice is much appreciated as I am out of my comfort zone haha.

Thank you

[Snooze]

Use ALT+W/S to set trim, and try not to use ASAS on spaceplanes. Avionics is best (usually) unless you're sending up Arkbird-type planes (Ace Combat 5, I went there).

Also, try to keep all your fuel as centered on the aircraft as possible so that as it drains it doesn't shift your CoM much.

Aside from that, angle your wings by 5 degrees. Without mods, wings with zero AoA generate no lift.

[GreeningGalaxy]

I've always wondered this; what exactly is wrong with using ASAS on spaceplanes? I use it all the time and I've gone all over Kerbin's SoI with my crafts with little trouble. Avionics packages just seem to make my planes dive, or flip out, or do anything besides go forward which is usually what I want. I mean, I can see how having to choose between having your heading absolutely locked or free to blow in the wind could be an issue, but it's usually not, especially with trimming.

I guess I need to experiment more, but I'm interested to hear an experienced opinion on the matter.

[Snooze]

It depends on how much control you want to have while your ASAS or Avionics Package is active.

With Avionics you can exercise a great deal more control than you can with ASAS. Personally, I prefer my spaceplanes to handle like planes and not as rockets with a unconventional flight path. That's not slighting ASAS in any way. I have some designs that use it. But for smaller, one-person planes designed to get into LKO, change out crew, and return? Avionics all day.

[foamyesque]

Well, first off, as I would always recommend to anyone building planes, get FAR. It will make life both more interesting and real-world research more applicable. pWings will also make your life much less painful.

Secondly, you've probably built your plane to be too stable and/or have zero AoA when the nose is level. I would suggest canting up a wing section ahead of your CoL and down behind your CoL, like so \____/ (vertical scale exaggerated) to help provide a natural pitch-up.

[PixelStache]

With the new asas systems of .21 it'll be a lot easier to use planes, as there isn't as much jerking around. Like Snooze says, holding alt while pitching up or down will trim your controls to hold a direction constantly, which helps. In general though, I've found that smaller planes are much more predictable, and keeping the CoM and CoL in line with the engines at the center of the fuselage will make things a bit easier on you.

When you finally take on the challenge of getting an SSTO plane from the runway to orbit, take a look at harvesters post from a while back. It helped me out tons!