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Deorbit and land the Space Shuttle
By Kevin Stoffel
Start docked to the ISS, at about 385km alt (estimate).
Keep an Eye on your orbital path on the Map MFD. When it looks as if the orbit will intersect Edwards in 2 orbits, do the following....
UNDOCK from ISS.
Close CBDs (cargo bay doors)
Turn retrograde, and burn at ApD, to reduce PeD to 360km alt over the surface. (Should be PeD 6.732 if I remember correctly).
At Alt of 360km, and hopefully at PeD, burn retrograde to circularize the orbit to 6.732 x 6.732, eccentricity of 0.00 (or there abouts...)
Wait until you are even with edwards, but still 1 orbit away from alignment with Edwards on your orbital track.
Set Surface Base target to Edwards.
Watch the distance to base number. It should be moving
UPWARDS, indicating that you are moving away from Edwards, which you should be at this point. If its still going down, give it a few minutes and check again. The point I normally do this is about over Texas, and one
orbit from where I would land at edwards. Again, watch the distance to target base number on the Map MFD. It will go all the way up to about 19.08 and then start to come back down again, showing that you are once
again moving towards edwards.
When the distance come back down to 18.50, its time to burn retrograde, until PeD = 6.371
When PeD = 6.371, you should be at ABOUT 17.00 distance
from the surface base, and on the orbital path that will take you directly over edwards, or close enough that you can correct later on during the approach.
When burn is complete and PeD = 6.371, turn prograde.
At about an altitude of 175km, bring up the SURFACE MFD,
and use Hlevel to roll wings level. I usually use hlevel to get my wings level, then use the RCS thrusters (1 and 3 on numeric keypad) to get my nose perfectly aligned in the YAW axis with my Velocity vector. Then I
KILLROT, and press Hlevel again. This makes sure that you are pointing the right direction for reentry, and that you will stay pointing the correct direction. Hlevel is just for now to keep wings level, and a good
view of earth =)
When alt is 135km, KILLROT. The nose will start to climb
up the climb ladder. This is normal and good. When the nose hits about 38 degrees, use thruster to keep it at about 38-42 degrees. I usually keep it at 38.
You will really start to feel the effects of the
atmosphere at about 90km, and the nose wants to go down. Dont let it, or you will burn up. (cant wait till THAT is modeled LOL )
At 84km ALT, Press P, to autopitch the shuttle to 38
degrees. If you have the Version 2 or higher shuttles, I know this works. Not sure about previous versions...
If not, keep the pitch at 38 degrees manually. This is a
biznizitch to do, so be prepared to take about a half hour to reenter if you are going to have to do it manually (without auto pitchup).
Dont worry too much about your velocity vector during
the heating phase, because it doesnt reeeally matter at THIS point. Right now you are just bleeding off energy.
Keep an eye on your forward velocity and acceleration
meters during the reentry. Dont let the Acc go over 30.00 (3gs). If you did everything right so far, it shouldnt. However you will know if it does, because an audible alarm will sound. But dont worry, I know you did
it all right so far.
When the forward velocity reads 4.500km/s, get ready to do another maneuver. This is where it gets a bit tough.
At forward velocity of 3.800km/s, disengage the
autopitch, and MANUALLY lower the pitch to about NEGATIVE 1 degree. Thats one degree BELOW the 0 line on the pitch ladder. Make your downward motion from 40 to -1 a smooth, but quick action.
Dont do it too fast though. I usually do about, say...
10 degrees per second. That may be a little faster then what I really do... not sure. You will know if its too fast or two slow, because the g meter will sound that alarm. Even if it does though, dont worry about
it, you can still come down no problem. You just pulled a few extra G's there then you should have.
Keep the nose between - 0.5 and - 2.0 degrees. At this
point, acceleration meter should read about -2.0 to -2.8. Less is ok too, and a LITTLE bit more wouldnt hurt for just a few seconds, but remember, any speed that is lost, cant be regained, and speed is distance. You
can always bleed it off later, and you will.
Now that the pitch is about neg 1 degree, the speed should be about 3.500km/s or there abouts.
This is the point at which you can make adjustments to the lateral direction of the velocity vector.
At the top of the HUD, when in Surface mode, there
should be a heading bar up top. Along that heading bar, should be what looks like a "V" (I think....) That "V", is the direction the heading the surface base (Edwards) is from your current
position on the globe. The trick here, is to keep a SLOW... and I mean very slow, descent going, by maintaining the neg 0.5 pitch angle, and at the same time, turning horizontally (with Number Pad 4 and 6 keys), to
align the direction of the velocity vector, with the same heading as the target base. You will know this has been accomplished, when you can roll wings level, the velocity vector is in the center of your nose marker
on the Climb ladder, and the direction to target base, on the HUD heading indicator, are all aligned in front of you. This means your velocity vector will take you to edwards.
Use small corrections to keep the velocity vector, your
nose, and the target base heading indicator, aligned. This is not really hard to do, and anyone who has used any time of FLIGHT simulator knows the process of banking to turn.
Keep an eye on the distance to target base on the MAP
MFD now, and when the distance reads about 1000kms, your speed should be about low enough to do a roll reversal. This is a simple process which I will explain here.
Roll about 80 degrees bank to the left. Remember to use
a little bit of upward pitch force to make the turn actually happen. When you are pointing about 25 degree to the left of the heading of the target base, roll wings level, and begin a 80 degree bank right turn. Pass
the heading of the target base, and turn for an additional 25 degrees to the right. This is the same exact movement we just made to the left, with the exception, that it is now to the right.
Pretty simple so far.
Once at 25 degrees heading to the right of the target
base heading, roll wings back level, and turn left again until your velocity vector is alligned with the heading to target base on the heading indicator on the hud. Now, you are heading back towards edwards again,
and you have just bled off quite a bit of excess speed. I probably should have noted this before, but the correct rate of upward pitch to use during the bank, will indicate about 10m/s to 15m/s deceleration on the
Surface MFD. I try to make it close to 10m/s
Now, you should be pretty close to edwards according to the Map MFD, which should have you at about 800-500 kms out. This is fine.
Try to keep speed at about 1.500 km/s forward velocity at this point.
When distance to edwards is about 120kms, you should see
the runway. Now, its like a normal approach. Put the nose down below the horizon to get the velocity vector on the VASI lights before the runway. Turn to line up, and keep a steady descent. Use the speedbrakes to
get speed to about 900 m/s. When distance is about 50km, reduce speed to about 700m/s.
Keep aligned with the runway and keep a steady descent
to hit the VASI lights before the runway. Yes , right now we are not actually descending to the runway, but rather, the red and white lights about 1000 feet BEFORE the runway. Ideal approach has a 20 degree descent
to the lights. At about 3000 feet, reduce speed to 250m/s.
Use slight taps of the speedbrake to try to keep the speed at 250m/s
When alt is 1500, start to bring the velocity vector up
to have a landing at the beginning part of the runway. Reduce speed to 220. Drop landing gear at 500 feet altitude. Speed should be dropping now, and at about 200m/s.
Target is to be at 180m/s over the runway threshold and
at 170m/s forward velocity. pitch up when over the threshold to keep the velocity vector at about where neg 0.5 degrees would be in the pitch ladder. Point is to land the shuttle with a POSITIVE pitch, and a
NEGATIVE velocity vector. This should occur at about 150m/s or so. Once down, deploy speed brakes, and use rudder to keep aligned with the centerline. When aligned, engage both wheel brakes, (Comma and Period key on
the REGULAR keyboard pad), and HOLD those two keys. They are not toggle type brakes. That would not be very realistic now would it? As long as you are holding comma and period, the brakes are slowing you down. I
usually release the brakes at 50m/s. Drag chute separates at 30m/s. Then, just let the natural forces of nature bring you to a stop.