1st digit: Booster Type:

1B = RSRMV (updated)

1C = RSRMV

2B = ATK Advanced Booster

2C = Pyrios (2xF-1B)

3 = Aerojet (3xAJ1E6)

4 = ATK Advanced Booster

2nd digit: Core Type:

C = Boeing IAC2012

B = Boeing IAC2013

3rd digit: Number of RS-25D engines

4th digit: Upper Stage Engine Type:

A = RS-25D

B = MB-60

C = RL-10C-2

J = J-2X

O = AJ10–190

V = Vinci

5th digit: Number of Upper Stage Engines

.6th digit: Variation Number

The following configurations have been simulated to a 200 km 28.45° orbit:

Name | Booster | Core | Upper Stage | Payload (t) | Comment |
---|---|---|---|---|---|

SLS1 | RSRMV | 4 x RS-25D | 1 x RL-10B-2 | 89.0 | Core at 109%. Standard Block I. |

SLS1B | RSRMV | 4 x RS-25E | 4 x RL-10C-2 | 97.1 | Core at 111%. Standard Block IB. |

SLS2B | ATK AB | 4 x RS-25E | 4 x RL-10C-2 | 113.4 | Core at 111%. Standard Block IIB. |

SLS2B4V4 | ATK AB | 4 x RS-25E | 4 x Vinci | 120.2 | Core at 111%. |

SLS2B4B4 | ATK AB | 4 x RS-25E | 4 x MB-60 | 126.1 | Core at 111%. |

SLS2B5C4 | ATK AB | 5 x RS-25E | 4 x RL-10C-2 | 117.9 | Core at 111%. |

SLS2B5B4 | ATK AB | 5 x RS-25E | 4 x MB-60 | 136.1 | Core at 111%. |

SLS1C4J2.0 | RSRMV | 4 x RS-25D | 2 x J-2X | 97.7 | Core at 110% |

SLS1C4J2.1 | RSRMV | 4 x RS-25D | 2 x J-2X | 72.1 | Core at 110% with 65% thrust bucket |

SLS1C4J2.2 | RSRMV | 4 x RS-25D | 2 x J-2X | 102.8 | Core at 109% with optimised upper stage |

SLS1C4J1 | RSRMV | 4 x RS-25D | 1 x J-2X | 103.3 | " |

SLS1C4A1 | RSRMV | 4 x RS-25D | 1 x RS-25D | 107.5 | " |

SLS1C5J1 | RSRMV | 5 x RS-25D | 1 x J-2X | 118.2 | " |

SLS1C5J2 | RSRMV | 5 x RS-25D | 2 x J-2X | 123.7 | " |

SLS1C5J3 | RSRMV | 5 x RS-25D | 3 x J-2X | 122.2 | " |

SLS1C6J2 | RSRMV | 6 x RS-25D | 2 x J-2X | 133.0 | " |

SLS2C4B2 | 2 x F-1B | 4 x RS-25D | 2 x MB-60 | 121.8 | " |

SLS2C4J2 | 2 x F-1B | 4 x RS-25D | 2 x J-2X | 129.0 | " |

SLS2C4B4 | 2 x F-1B | 4 x RS-25D | 4 x MB-60 | 129.4 | " |

SLS3C4B4 | 3 x AJ1E6 | 4 x RS-25D | 4 x MB-60 | 132.6 | " |

SLS4C4J2 | ATK AB | 4 x RS-25D | 2 x J-2X | 121.5 | " |

SLS4C5J2 | ATK AB | 5 x RS-25D | 2 x J-2X | 140.2 | " |

SLS1C4J1.1 | RSRMV | 4 x RS-25E | 1 x J-2X | 113.6 | Core at 111% thrust |

SLS2C4J2.2 | 2 x F-1B | 4 x RS-25E | 2 x J-2X | 133.2 | " |

SLS3C4J2.2 | 3 x AJ1E6 | 4 x RS-25E | 2 x J-2X | 136.2 | " |

SLS4C4J2.2 | ATK AB | 4 x RS-25E | 2 x J-2X | 124.8 | " |

SLS1C5J2.1 | RSRMV | 5 x RS-25E | 2 x J-2X | 130.6 | Heavy core at 111% thrust |

SLS1C6J2.1 | RSRMV | 6 x RS-25E | 2 x J-2X | 137.0 | " |

SLS4C5J2.2 | ATK AB | 5 x RS-25E | 2 x J-2X | 144.1 | " |

SLS1C6J2C4 | RSRMV | 6 x RS-25E | 2 x J-2X | 140.7 | LUS and 4 x RL-10C-2 CPS use common bulkheads. |

The following configurations have been simulated to a 96x241 km 28.45° orbit:

Name | Booster | Core | Upper Stage | Payload (t) |
---|---|---|---|---|

SLS4C5J2.1 | ATK AB | 5 x RS-25D | 2 x J-2X | 146.2 |

The following configurations have been simulated to a 400 km 51.6° orbit:

Name | Booster | Core | Upper Stage | Payload (t) |
---|---|---|---|---|

SLS1B4O1 | RSRMV | 4 x RS-25E | 1 x AJ10-190 | 75.4 |

SLS2B4O1 | ATK AB | 4 x RS-25E | 1 x AJ10-190 | 91.3 |

SLS1C4 | RSRMV | 4 x RS-25D | - | 28.7 |

SLS1C4O1 | RSRMV | 4 x RS-25D | 1 x AJ10-190 | 50.5 |

I have written a general purpose simulation program that simulates the Space Shuttle. The heart of the simulation program is rocket.pas which contains procedures used to determine the trajectory of any rocket using the Runga-Kutta fourth order method. I first wrote this for a Saturn V trajectory simulation program. rocket.pas is separate from the stage*.pas procedures which generate the appropriate values (such as thrust F, propellant rate Rp, time increment dt, etc.) for input to rocket.pas. const.pas contains the constants used in the stage*.pas procedures.

This program was compiled using Free Pascal.

When you execute "sls1c" you will get the following response

Enter output filename (return is standard output): t a vi h0 r0 alpha beta theta Pq m0+Me sec m/s^2 m/s metres metres deg deg deg Pa kg ----------------------------------------------------------------------------- Turn time (s)?

You should then enter the duration in which you want the rocket to pitch over. The pitch angle can be adjusted in const.pas with name angle1. The rocket then takes off vertically before pitching over for the time specified. This time does not include the time to move the rocket to and from angle1, so even if you set the angle to 0, the rocket will slightly pitch over. The output from the program has in each line

t time, seconds a acceleration (excluding any external forces such as gravity and air drag); metres per second per second vi inertial speed; metres per second h0 altitude above planet's surface; metres r0 range; metres alpha thrust angle relative to inertial velocity vector or angle of attack; degrees beta velocity angle relative to motionless planet; degrees theta velocity angle relative to rotating planet; degrees Pq Dynamic pressure; Pascals m0+Me the mass of the rocket

The first stage performs a gravity turn keeping the thrust vector and the air
velocity vector the same. Thus the air angle of attack is zero. At the end of
the first stage burn you are asked for the maximum angle of attack. This is
relative to the inertial velocity vector. When this angle is greater than the
air angle of attack, the angle of attack will gradually increase. This is due
to the trajectory algorithm trying to maintain the rate of altitude increase.
We have *h*_{0} as the height, *h*_{1} =
*dh*_{0}/*dt* is the rate of increase of height, and
*h*_{2} = *dh*_{1}/*dt*. Our orbit algorithm
has *h*_{2} proportional to
sign(*h*_{1})|*h*_{1}|^{pow}. pow is a
constant and is set to 2.0. This seems to be not the most optimal algorithm,
but I have found that it does a reasonable good job, getting you where you want
to go.

The angle of attack will increase until the maximum angle is reached and be maintained there until centrifugal acceleration becomes strong enough. The angle of attack will then naturally decrease. The reason that "sls1c" needs this algorithm is that the engines doesn't have enough thrust to allow for a zero angle of attack. Well, this is what I found anyway. If anyone has a better way that uses a smaller angle of attack, I would be glad to hear from them.

One area I would like to improve is determining the coefficient of drag (cd) versus speed. The values I used were from the Mars Project by Werner von Braun for a 20 m diameter rocket. If anyone can help me out on this, I would greatly appreciate it.

14 Oct 2018 Added SLS1

20 May 2016 Corrected SLS2B5B4. Added SLS2B4V4.

19 May 2016 Added SLS2B5B4

18 May 2016 Added SLS1B4O1 and SLS2B4O1

8 Mar 2016 Added SLS2B4B4

7 Mar 2016 Added SLS2B5

4 Mar 2016 Added SLS2B

3 Mar 2016 Added SLS1B

20 Jul 2015 Updated SLS1C6J2C4

7 Jul 2015 Added SLS1C4J1.1, SLS1C5J2.1 and SLS4C4J2.2

6 Jul 2015 Added SLS1C6J2.1, SLS2C4J2.2, SLS3C4J2.2 and SLS4C5J2.2

24 Jun 2015 Added SLS1C6J2C4

28 Dec 2013 First release

Any comments, questions, additions, or corrections should be directed to

Steven S. Pietrobon Small World Communications 6 First Avenue Payneham South SA 5070 Australia |
ph. +61 8 8332 0319 fax +61 8 7117 1416 email: steven@sworld.com.au web: http://www.sworld.com.au/ |