Proper SSTO Re-Entry

[SkiRich]

I have watched plenty of videos of cool SSTO builds, but one common theme has been the SSTO on re-entry goes end over end spinning violently until in the lower atmosphere.
I really want a space shuttle but that re-entry bugs me.
Is there a way to build an SSTO that does not look like a paper plane in the wind on re-entry?

Video would be nice if you know of one.

[GunsForBucks]

you want something using Mk2 parts? Is that what you mean by SSTO or any shuttle?

The main thing I have found is to keep the nose a little heavy especially with the MK3 stuff, most of my builds don't get wonky on entry once sorted out.

[miklkit]

The trick is to build it so that it is a little nose heavy with empty tanks, but still have it be able to take off with full tanks. This one is a poor design that is barely able to take off and is barely stable enough when coming down. Check out how far forward the COM is.
https://steamcommunity.com/sharedfiles/filedetails/?id=2157910295

[SkiRich]

Really thats the trick? Just a heavier nose? (I get I need to test this and do fine tuning) but in general just a heavier nose prevents or at least mitigates the wonk? Interesting, and yes its probably gonna be MK3 build, about as close as I can get to a real US shuttle look as I can, but probably have some jet engines to fly it back to the KSP. Its not going to be a space plane, just a cargo hauler with rocket booster takeoff.

The way I'm playing I want to have a small amount of realism.

Assuming an MK3 build how do you hide the landing gear pods so they dont burn up on re-entry?
Also assuming coming through the atmosphere bottom first just like a shuttle.

[Ogre420]

One *TRICK* is to add another control point (probe/docking port) that is pointed a bit downwards (Say 15 - 30 deg.).

When you re-enter the atmosphere just control from there and tell it to point prograde.

Since it's pointed *DOWN* 15 -30 deg. it will hold the nose *UP* by 15 -30 Deg. when going prograde.

Note: The angle *DOWN* for the control point depends on the type of craft, you may have to fiddle around to find a correct re-entry angle. (May want to add some MOAR SAS to help control it.

Note 2: Don't forget to return control to a forewards facing control point for landing.

******
Another *TRICK* is to adjust all the aero-control surfaces for better control.

Lower the sensitivity of the control surfaces to 25% of normal and see if that helps...
(I've had a lot of problems with control parts OVER controlling and causing oscillation unless I lower the throw limits on the control surfaces)

******

*Trick* #3

Also in the SPH right click on each control surface and assign the PROPER control settings for Yaw/Pitch/Roll...

Wing elevons close to center (Pitch ONLY)
Wing elevons on outer part of wing OR only elevon on wing (Pitch, Roll)
Rudder/Tail Fin (Yaw Only)
Elevator (Pitch Only)
Canard [Forward/Nose Winglet] (Pitch only)

Setting this stuff made all my planes fly better.

******

[SkiRich]

Originally posted by Ogre420:

One *TRICK* is to add another control point (probe/docking port) that is pointed a bit downwards (Say 15 - 30 deg.).

When you re-enter the atmosphere just control from there and tell it to point prograde.

Since it's pointed *DOWN* 15 -30 deg. it will hold the nose *UP* by 15 -30 Deg. when going prograde.

Note: The angle *DOWN* for the control point depends on the type of craft, you may have to fiddle around to find a correct re-entry angle. (May want to add some MOAR SAS to help control it.

Note 2: Don't forget to return control to a forewards facing control point for landing.

******
Another *TRICK* is to adjust all the aero-control surfaces for better control.

Lower the sensitivity of the control surfaces to 25% of normal and see if that helps...
(I've had a lot of problems with control parts OVER controlling and causing oscillation unless I lower the throw limits on the control surfaces)

******

*Trick* #3

Also in the SPH right click on each control surface and assign the PROPER control settings for Yaw/Pitch/Roll...

Wing elevons close to center (Pitch ONLY)
Wing elevons on outer part of wing OR only elevon on wing (Pitch, Roll)
Rudder/Tail Fin (Yaw Only)
Elevator (Pitch Only)
Canard [Forward/Nose Winglet] (Pitch only)

Setting this stuff made all my planes fly better.

******

Ah thanks, good tips.
I remember watching a video that used a BeepBox control node embedded on the of the ssto slightly tilted off center for that.

[Azunai]

it's often easier to balance the CoM when you put the engines on the sides rather than in the back. think of the british "Skylon" spaceplane concept rather than the old US space shuttles.

when the heavy engines and the cargo hold are roughly in the center and you have fuel tanks ahead of and behind the cargo hold then the CoM won't shift much as you burn the fuel. it will actually move a bit forward as you use up the fuel if you have a cockpit (much heavier than the empty fuel tanks at the back)

[GunsForBucks]

In terms of re-entry I don't use the heating, so take this a with a grain of salt.

But typically I will get my orbit 80kish <70-90> and a quarter of the way back from KSC do a retro burn to put your orbit in the water past KSC. As you drop the orbit will collapse to bring it to KSC but it's pretty much just a straight glide at that point until you get close to the runway.

I don't use any mods so I have no idea what they may be making you do in terms of reentry.

[miklkit]

All of that is far too advanced for me. I just balance the design and it pretty much flies itself. Just a nudge to get the nose down now and then is all it takes until it is slow enough to fly normally.

[Patriot03]

You don't have to do that especially if you're just coming in from LKO or from mun.

I haven't made an SSTO with FAR yet, but before FAR I actually found that a steeper entry was more useful since you quickly get past the cooking part and just rapidly slow down. I would experiment with unmanned craft.

On my way into the first layers of the atmosphere I hold my plane essentially 90* pointed down or up as much as I can until I feel like I'm ready to dip into the deeper levels and that's when I pull as hard as I can into the atmosphere.

[Patriot03]

Originally posted by Ogre420:

One *TRICK* is to add another control point (probe/docking port) that is pointed a bit downwards (Say 15 - 30 deg.).

When you re-enter the atmosphere just control from there and tell it to point prograde.

Since it's pointed *DOWN* 15 -30 deg. it will hold the nose *UP* by 15 -30 Deg. when going prograde.

Note: The angle *DOWN* for the control point depends on the type of craft, you may have to fiddle around to find a correct re-entry angle. (May want to add some MOAR SAS to help control it.

Note 2: Don't forget to return control to a forewards facing control point for landing.

******
Another *TRICK* is to adjust all the aero-control surfaces for better control.

Lower the sensitivity of the control surfaces to 25% of normal and see if that helps...
(I've had a lot of problems with control parts OVER controlling and causing oscillation unless I lower the throw limits on the control surfaces)

******

*Trick* #3

Also in the SPH right click on each control surface and assign the PROPER control settings for Yaw/Pitch/Roll...

Wing elevons close to center (Pitch ONLY)
Wing elevons on outer part of wing OR only elevon on wing (Pitch, Roll)
Rudder/Tail Fin (Yaw Only)
Elevator (Pitch Only)
Canard [Forward/Nose Winglet] (Pitch only)

Setting this stuff made all my planes fly better.

******

Pro tip, you can hold down left alt and then any control input you give it acts like a trim. Pressing "Alt X" cancels out all trim, please not that IIRC this only works when SAS is disabled. Which is fine, if you need SAS to fly an aircraft then it's designed wrong.

So doing that you can hold any angle of attack you light without having to mount another control pod.

I use trim for all of my aircraft.