DG-IV Hands-on reentry

TMac3000

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I have been making the attempt to reenter the DG-IV with no autopilot. I can get it into the atmosphere, down to around 30-45 km, but then it starts to climb again. At this point, I am doing about Mach 5, so if I try to force the ship lower the hull temp shoots up and she threatens to burn up. How do I make her keep decelerating?
 
Switch to ATM mode, set a little trim, and do some S-turns. If that doens't work watch your initial speed before reentry and get that as low as possible.
 
Keep your angle of attack up. 40 degrees works well... remember that lowering your angle of attack will tend to increase your vertical velocity, and vice versa.
 
The altitude and speed sound about right, you're definitely suborbital. This means that if you are climbing it's because you have too much lift. If you aren't decellerating much it's because you don't have enough drag. It sounds to me like you are in a low Angle of Attack conventional flight mode rather than a high AoA aerobraking flight mode.

There are two solutions that come to mind:

1. It is possible to re-enter in a low AoA flight mode, but it takes much longer to lose your speed. You should have the controls set to Elvon & nosewheel (not ATM Auto). Use the trim keys (ins and del) to maintain a very slow 10 - 15 m/s descent rate. Keep an eye on the hull temps, and once your velocity is below 3k and the hull temps have dropped engage the airbrake.

2. Use a high AoA re-entry profile like the autopilots do. If you were attempting to to this, you may have had a problem keeping the nose up. If you can't keep the AoA high enough you'll get to much lift and climb. There's a trick to make it possible to hold the high AoA profile - set the controls to Elev & nosewheel, then use [F8] to switch o "glass cockpit" mode. Click on the [ROT] button on the upper left corner of the display, then use [F8] again to return to 2-d panel view. You will now have both airfoils and RCS working together. Just adjust the trim all the way up, and a bit of back stick as needed. Start with about a 40 degree AoA. Watch the VACC to determine the lift you are getting. If VACC is positive pitch up more, and vice versa. Try to maintain about a 80 m/s descent.

Either way, you can also use roll to control your VACC. The higher the roll angle, the more lift is being used to turn the craft and less used to counteract gravity. In short, more roll = lower VACC. An example of this would be the S turns used by the shuttle.
 
Thanks everyone for the help. I completed a manual reentry last night, and didn't have to do any S-turns or anything. All I had to do was set the trim all the way back, and then zero it out at Mach 2.5

Too bad I ended up 1500 km from the Cape:(
 
"Drive" back home with the fuel you have left (if any) :)
(Using atmospheric flight AP)
 
Targeting a base reliably during re-entry is almost impossible without AerobrakeMFD. Press [PRJ] to select Graph/Map mode, then [PRJ] to get the map view.
 
Very slight necropost:P

Targeting a base reliably during re-entry is almost impossible without AerobrakeMFD. Press [PRJ] to select Graph/Map mode, then [PRJ] to get the map view.

I can now do it with stock MFDs only.
The technique I figured out works like this: arctan(altitude/distance), and use the result as your reentry angle in the Deorbit Display (DISP 2).

The few times I have done this, it's always landed me within 600 km of my intended base. Which incidentally, is on the bleeding edge of the DG-IV's post-reentry cross-range.
 
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