Launch (procedures)

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Parameters: HAB fuel load @ MES = 25000 kg

intercept target’s orbital altitude = 315 km
HAB intended orbital altitude = 350 km (so we end up above the target)

Abreviations: MES = main engine start

MECO = main engine cut-off
SRBI = solid rocket booster ignition
MET = mission elapsed time
Qmax = point of maximum dynamic atmospheric pressure indicated
by top readout in second display box on orbit software


Plan: The spacecraft is vulnerable to re-entry in the case of engine failure until orbital Vtan is reached. Launch to orbit profile is designed to minimize the time taken to reach ref Vo orbital speed. Initial vertical launch takes the spacecraft out of the thick part of the atmosphere as rapidly as possible to minimize fuel use and time to reach orbital speed. Roll to ccw prog orientation is initiated at a point such that when ccw prog orientation is reached, the spacecraft has the necessary vertical velocity to coast up to the desired orbital altitude while the engines are used only to accelerate the spacecraft to the necessary Vtan as rapidly as possible. If the procedure is followed, the spacecraft should reach the desired maximum orbital altitude (Vcen = 0) at the same time as Vtan reached the required value to maintain a circular orbit at that altitude. This minimizes the time taken to circularize the orbit after final MECO. With the correct angular separation from the target at liftoff, the spacecraft should reach the top of its orbit and complete circularization just as the target pulls along side.

Procedure

GUIDO confirms time that target reaches angle for spacecraft liftoff using ORBIT5tm. This time is communicated to FIDO who ensures that it is loaded into ORBIT5sd as the mission start time (MST).

MET Conditions Actions
-0:30:00 Flight engineer cold-starts reactor & brings all systems online.

HAB main engine systems remain off.

FIDO ensures ABORT landing site is entered into ORBITsd: 17oW

Pilot: cen=HAB; targ=earth; ref=earth; NAVmode=deprt ref

press “t” and <space> to lock view center

targ = ISS

HAB EECOM performs pressure test:

Each compartment pressurized 20% above ambient one at a time.

HAB & MC EECOM confirm that: pressure is stable.

pressure warnings activate

door warnings activate

HAB EECOM returns each compartment to normal pressure

HAB & MC EECOM confirm all compart @ normal gas pressures.

-0:10:00 Flight engineer confirms with MC that all engineering systems are functioning within limits.

HAB fuel load = 26000 kg (load or unload as needed)

Pilot and GUIDO confirm RSCP = on

RSC fuel = 100

Pilot and GUIDO confirm RSCP system functioning

Pilot makes small impulses using RCS in all 4 directions

Pilot & GUIDO confirm that RSC fuel drops and recharges

Main engine test

ION and ACC on for all engines

fuel injectors OFF

10% throttle: main bus = 48745.2A 9988V; 1765 kg/hr fuel flow

-0:06:45 HRT = 40o Mission commander and flight director confirm that:

a) all personnel are in place in spacecraft and mission control

b) all software is running and is time synchronized

c) that all spacecraft systems are configured for launch

-0:04:15 HRT = 30o Mission commander and flight director confirm GO FOR LAUNCH status from all stations in HAB and MC.

Mission commander and flight director confirm GO FOR LAUNCH status with each other.

-0:01:50 HRT = 20o Engineer and GUIDO confirm 25000 kg fuel on board

GUIDO displays intended track: press Z & select launch1 to redraw track, press z

Pilot and GUIDO confirm NAVmode=deprt ref

-0:01:00 Engineer sets HAB engine fuel injectors to ON

Engineer and FIDO confirm fuel injectors, ION, ACC, RSCP are ON

-0:00:30 Pilot: throttle to 70%

GUIDO & Engineer confirm 70%@

-0:00:20 Engineer & FIDO confirm engineering parameters are within limits:
main bus: 338709.3A 9915V
fuel flow: 12203 kg/hr
reactor temp: climbing (eventually stabilizes @ 102)

Pilot & GUIDO confirm engine acceleration >10.00 m/s2

-0:00:10 Mission commander confirms GO FOR LAUNCH status
-0:00:02 HRT = 12.92o Engineer initiates SRB ignition
0:00:00 HRT = 12.76o Pilot confirms SRB ignition and liftoff

Pilot & Guido confirm acceleration > 53.9 m/s2

(accel increases at constant engine setting as fuel mass drops)

0:00:02 Pilot: sets NAVmode = MAN
targ = Earth

GUIDO confirms new settings

0:00:17 Qmax

Vcen > 480 m/s

Pilot increases throttle to 90%

GUIDO confirms throttle and Vcen

Engineer & FIDO confirm engineering systems within limits

main bus: 434430.8A, 9891V

fuel flow: 15649 kg/hr

reactor temp climbing (eventually stabilizes @ 107)

Pilot and GUIDO confirm accel > 56.9 m/s2

0:00:31 alt = 13.00 km

Vcen < -740 m/s

Pilot initiates 2o/s ccw roll

HAB & MC EECOM confirm: ambient pressure drop

compartment pressure stable

interior door warnings off

exterior door warnings on

compartment gas levels stable

0:1:17 oriented ccw prog

Vcen < -1640 m/s

Vtan > 1520 m/s

alt > 70.00 km

apoapsis > 215 km

Pilot: roll maneuver to ccw prog completed by pressing F2

GUIDO confirms NAVmode = ccw prog

GUIDO confirms orbital parameters within normal limits

0:01:32 alt = 100.00 km

Vcen < -1550 m/s

Vtan > 2550 m/s

Confirm atmospheric drag < 0.001 m/s2
0:02:01 alt = 140.00 km

Vcen < -1300 m/s

Vtan > 4000 m/s

apoapsis > 280 km

Confirm SRB shutdown

Pilot and GUIDO confirm accel > 13.1 m/s2

0:02:15 ABORT decision Engineer & FIDO check engineering systems within normal limits

reactor temp < 107

main bus: 434430.8A, 9891V

fuel flow: 15649 kg/hr

accel > 13.1 m/s2

HAB & MC EECOM confirm: ambient pressure zero

compartment pressure stable

interior door warnings off

exterior door warnings on

compartment gas levels stable

int./ext. RAD levels acceptable

If abort is called: set targ = TARGET
initiate 2o/s cw roll for 22 s then null roll rate
maintain max possible thrust
MECO when orbit projection just passes target
Follow landing from orbit procedures
If no abort is called: GUIDO checks speed & position variances from intended orbital track. Small

variances (<1000 m and <25 m/s) are acceptable & expected. For large variances or if the variance is

increasing rapidly:

Speed: GUIDO requests small changes in throttle to correct variance

Position: Pilot sets NAVmode to manual

GUIDO magnifies image to check direction of variance, requests roll in opposite direction
- roll @ 1o/s for a few seconds, null roll, check if variance starts to decrease
- NAVmode to ccw prog once a slow variance reduction begins
Perform opposite maneuver to zero out variance rate
0:03:11 apoapsis > 300 km

Vcen = -900 m/s

Vtan > 4900 m/s

Orbital parameters within limits.

Continue to monitor apoapsis.

Engineering systems within normal limits.

0:03:41 alt = 250 km

apoapsis > 305

Vcen = -760 m/s

Vtan > 5300 m/s

Orbital parameters within limits.

Continue to monitor apoapsis.

Engineering systems within normal limits.

0:04:31 apoapsis = 320 km

alt > 280 km

Vcen = -525 m/s

Vtan >5900 m/s

Orbital parameters within limits.

Continue to monitor apoapsis.

Engineering systems within normal limits.

0:05:13 apoapsis = 330 km

alt > 300 km

Vcen = -400 m/s

Vtan > 6450 m/s

Orbital parameters within limits.

Continue to monitor apoapsis.

Engineering systems within normal limits.

0:05:47 apoapsis = 340 km

alt > 315 km

Vcen = -310m/s

Vtan > 6900 m/s

Orbital parameters within limits.

Continue to monitor apoapsis.

Engineering systems within normal limits.

0:06:06 apoapsis = 348 km

alt > 320 km

Vcen = -280 m/s

Vtan > 7200 m/s

MECO (critical that this happens at apoapsis = 348 km)

Engineer & FIDO confirm fuel remaining on board.

FIDO calculates fuel use per hour and compares to readout

- this is a check for leaks: the two rates should be similar

Orbital parameters within limits.

Engineering systems within normal limits.


The spacecraft now coasts up to the apoapsis with engines off.

Vcen and Vtan will gradually approach zero as the altitude increases.


Vcen will reach zero at the top of the orbit (apoapsis).

Since it is important that Vtan equal ref Vo at the top of the orbit, the

engines must be fired to accelerate the spacecraft so Vtan = re Vo

starting just before the top of the orbit, when Vcen is approx. -40 m/s

0:09:10 Vcen = -40 m/s

Vtan > 7150 m/s

alt = 348 km

Main engines to 100% thrust

Monitor Vtan

0:09:51 Vtan = ref Vo

Vcen = 0 m/s

alt = 350 km km

MECO

Evaluate Vcen and Vtan

0:10:15 If Vcen and Vtan have large variances from target values:
1) correct Vtan using main engines at small throttle settings
2) set NAV mode to deprt ref and adjust Vcen to zero
3) set NAV mode to ccw prog and reset Vtan to ref Vo

If Vcen and Vtan variances are small:

1) use RCS thrusters to correct each velocity
0:11:15 Confirm orbit cicularization at near 350 km (+-20 km)
0:11:30 HAB & MC EECOM confirm: ambient pressure zero
compartment pressure stable
interior door warnings off
exterior door warnings on
compartment gas levels stable
int. & ext. RAD levels acceptable
0:12:00 Confirm distance, direction, and relative speed for target
1) Set targ = desired target
2) Note direction vector to target
3) Note Vcen, Vtan, velocity vector to target
4) Note distance to target
0:12:30 Plan approach to dock with target.