Spaceport Earth

Joe Pappalardo, Cedar Mill 629.4, 2017

A collection of essays by a staff writer for Popular Mechanics.

Vomit Comets

Many of the essays are about small companies at the small desert airports designating themselves "spaceports", where vomit comets might someday take off and land for brief thrill rides above the 100 km Karman line.

The Karman line is a legal fiction; it is too high for aerodynamic lift, and too low for orbit. It is the demarcation between national airspace (where a sovereign nation are permitted to shoot down intruders), and "outer" space, where foreign orbiting objects can pass overhead without interference. That's an interesting place; however, the potential energy is less than 3% of orbital energy, and 1.5% of escape energy. Achieving orbit with rockets requires stored propellants and suffers from the Tsiolkovsky exponential, so the extra difficulty of reaching "real" space is far more than 30 or 60 to one.

Either way, the difficulty can be far less with a launch loop. Without the need for wings or onboard propellant, launch loops can launch vehicles to high orbit with less cost, energy, and risk than a vomit comet to the Karman line.

So, municipalities and taxpayers are paying for space travel and getting very expensive amusement rides. To date, no aircraft has flown to orbit, though hybrid aircraft like the space shuttle have flown back, after the lifting heavy wings and wheels with extra large rockets. After !SpaceX demonstrated vertical landing and reuse for first stages, a major justification for winged landing evaporated.

Wings may assist orbital return and landing at multiple sites, and increase survivable return to secondary landing sites for military missions in wartime, but new technologies may evolve to replace that function as well. I'm imagining a twin-fuselage aircraft like the LauncherOne mothercraft, with a net between the fuselages, designed for midair rendezvous with a spacecraft descending on parachutes. Make the net-toting aircraft robust and maneuverable; don't loft that capability to orbit with every mission.

Vertical Launch

The more interesting parts of the book are about historical and recent developments for vertical launch. Much of that is about !SpaceX, some about BlueOrigin, and some about less-well-known vertical launch sites like Wallops, Vandenberg, and Kourou.

Since the book was written, development of the !SpaceX Boca Chica launch site near Brownsville at the southern tip of Texas has slowed. Inadequate demand, perhaps; the world has more launch sites than mission types.

The book starts with the author's coverage of the last space shuttle launch; remarkably similar to my own "coverage" of the first space shuttle launch. Some interesting history of the "nationalization" of the Air Force Atlantic Missile Range into the Kennedy Space Center. p23 the author's photos of the !SpaceX innovative ball-and-socket stage separators are withheld; ITAR violation. p29 "I swear I feel a warm flash on my face" ... I remember that too.

Kourou spaceport replaced Hammaguir in the Algerian Sahara. 5.3N latitude, 25 percent fuel savings to GEO. First Ariane launch in 1979. p42 Charlie Ergen watches launch of his billion dollar satellite. p44 "weather satellite???"

p62 Mojave: 'nitrous oxide tank explosion kills three Scaled Composites employees. p79 premature manual deployment of "feather rudders" destroys Virgin Galactic SpaceShipTwo and kills copilot Michael Alsbury.

p97 Wallops: Antares engine (decades old) failure and explosion.

p101 Minuteman III, 341st Missile Wing, Malmstrom AFB, Montana. 150 out of 450 silos in MT and WY, 3 W87 warheads each. 750 km apogee. Launch Control Center 65 feet underground, controls 10 missiles, monitors 50 more. p103 main entrance through 1.5 meter blast door, emergency exit through sand-filled tube to surface. 1960s electronics, will keep running until 2030. p107 sampled missiles launched from Vandenberg, CEP 500 feet. Flight time = 186 miles moscow rotation, 1040.4 mph*cos(55.8°), 19 minutes. p115 Iridium NEXT satellites, 860 kg in LEO.

p123 Cape Canaveral SLS-41: Dream Chasser spaceplane (hypothetical, Atlas launched), Boeing CST-100 Starliner

p135 2015 June 28 ISS supply mission, Falcon 9 second stage fail at T+140sec.

p135 2011 August 24, Blue Origin crash near Van Horn Texas. New Shepard launcher. BE-4 engine. p145 !SpaceX in McGregor near Waco. 280 foot 500,000 gallon water tower tallest in US. p151 !SpaceX in Brownsville.

p175 bad trigonometry: Existing blimps flown ... 10,000 feet (range to surface 197 km)... over Baltimore could scan an area ... Upstate New York (320 km) ... Outer Banks (330 km) ... Ohio (360 km)

p176 World View Stratolite balloon, 76,900 ft, 23.4 km ... 0.4% of orbital energy.

p181 2016 September 1 SLC-40, Falcon 9, $200M 5.5 tonne AMOS-6 Facebook Comsat, static fire test obliterates rocket, damages pad and risks water systems and chiller for NASA's OSIRIS_Rex satellite. Suspected breach in second stage cryohelium system, but actually accumulation of LOX in COPV (Composite Overwrapped Pressure Vessel) between overwrap and aluminum liner.


SpaceportEarth (last edited 2018-08-07 20:33:15 by KeithLofstrom)