Senerio #2 Optimum:

SSS - Space Sling Shot feasibility wags with A HALF INCH LINE


Unobtainium towrope Assumptions:

I. Subsonic Line Operations at FL750.

Length: 10sm's long or 52,800 ft
Dia: .5 in or 12mm
Avrg. Tensile strength: Needs to be 200,000 lbs. not Vectran's
24,500lbs!

Cd 1.0
Line Drag at .82 Mach clb: 71,667 (D = 50,000 * 0.5/12 * 34.4 * 1.0
= 71666.6 lbs)
Deployed Wt: 7.7lbs/100ft. 4065 lbs (Vectan #'s) (52,800/100=528,
528(7.7)=4065.6

Thrust Assumptions:
6 GE C90s:

Thrust at S.L: 110,000 lbs * 6 engs = 660,000 total thrust at
S.L.
Thrust at FL500 (1/4 of S.L.): 165,000 lbs

Thrust at dismount: 165,000
Line Drag at Mach .82 -71,667
Residual thrust available for vehicles 93,333
Thrust needed for 747 only -40,000
Available for OrbitOne vehicle 53,333 lbs thrust

Hmmmmmm, this looks very Do-able.



II. Supersonic Line Operation at FL750:

Line Drag at Mach 1: 106,250 lbs (D = 50,000 * 0.5/12 * 51 * 1.0 =
106,250 lbs)

6 GE C90s:

Thrust at S.L: 110,000 lbs * 6 engs = 660,000 total thrust at S.L.
Thrust at FL500 (1/4 of S.L.):165,000 lbs

Thrust at dismount: 165,000
Line Drag at Mach 1.0: -106,250
Residual thrust available for vehicles 58,750
Total 747 thrust need: -40,000
Available for OrbitOne vehicle: 18,750

Hmmmmm, just do-able.

Note: Towship is a stripped-down 747-132SF. These supersonic line
calcs are for 10-15 seconds only in 30 degree towship bank.

Summary: We need some newer technology tether material that allows us
to weave it into a half inch thickness (so that line drag is
reasonable.) We need to stay with a six engine 747 if we're going to
do the slingshot maneuver. A twin tail might get fouled since the
tether is attached to the tugship CG near the main wing stations.
Durring bank the OrbitOne is going to pitch out to the side with the
line taunt. Right? So turn must be made opposite side that tether
runs by tail.

This drag bill Richard warned us about is a ****er!

pac