Value chain · CLM-1367
In plain terms
A long spinning cable in low orbit dips its end down to 150 km, grabs a cargo pod from a very fast plane, and flings it towards a high orbit.
The claim as recorded
The 2001 HASTOL Phase II study designs a rotating tether about 630-636 km long, spinning so its tip moves at about 2.5 km/s, to catch a 5,500 kg payload from a Mach 17 hypersonic airplane at 150 km altitude. It then tosses the payload into a transfer orbit to geostationary altitude. The whole facility masses just under 69 times the payload, and the payload feels about 1.5 g while attached.
Evidence behind this: T3, a contractor final report to the NASA Institute for Advanced Concepts; it permits "the study's design is Y", not that it was built or tested.
Scope and limits
A design study, never built. Two lengths are given: 630 km in the summary (PDF p.38) and 636,300 m in Table 3-3 (PDF p.39). Rechecks (my arithmetic): 0.00583 rad/s x 431,831 m = 2,518 m/s tip speed. 7,627 - 2,517 = 5,110 m/s, matching the airplane's speed at catch. 582 km - 431.8 km = 150.2 km tip altitude at catch. 2,517^2 / 431,831 m = 14.7 m/s2 = 1.50 g. 378,961 / 5,500 = 68.9 times payload. The catch is in the equatorial plane (PDF p.38); the "catch altitude" is the airplane's apogee, 150 km.
What it assumes
No assumptions are recorded against this claim.
Where it comes from
PDF p.38 / printed 32: "Capability to capture a payload from a Mach 17 hypersonic airplane at 150 km apogee altitude."; "Payload capacity of 5,500 kg."; "Orbit of tether after payload toss shall not allow the tether tip to drop below 80 km altitude."; Tether Length 630 km, orbit 582 x 805 km (paraphrase); "the tether must rotate with a tip velocity of 2.5 km/s"; release at 38.63 degrees from vertical gives a 682 x 35,790 km transfer orbit (paraphrase). PDF p.39 / printed 33, Table 3-3 (paraphrase): tether length 636,300 m; tip velocity at catch 2,517 m/s, at toss 2,481 m/s; angular rate 0.00583 rad/s; tether mass 323,311 kg; total facility mass 378,961 kg; rendezvous acceleration 1.50 g; airplane apogee 150 km at 5,110 m/s; tether centre-of-mass perigee 582 km at 7,627 m/s; centre of mass to grapple 431,831 m.
Basis: tether length (km, m); tip speed (m/s); catch altitude (km); payload mass (kg); acceleration (g)
Cite this
energyaperture.com/c/clm-1367
CLM-1367, Energy Aperture, as of 2001-10.
Connected records
Other published records linked to this one. A list, not a judgement.