Those among you who like their skies filled with black helicopters, or indeed secret space launch vehicles, might have already caught a quite remarkable March report in Aviation Week & Space Technology which claims that the US has successfully developed and tested a "two-stage-to-orbit system that could place a small military spaceplane in orbit" (see AWST pic, right).
The spook system, deliciously dubbed "Blackstar", allegedly comprises a carrier vehicle (codename "SR-3" according to AWST), to which is docked a reusable spacecraft (XOV or "experimental orbital vehicle"). On 4 October, 1998, claims AWST, eyewitness James Petty of Salt Lake City saw "a small, highly swept-winged vehicle nestled under the belly of the XB-70-like aircraft. The vehicle appeared to be climbing slowly on a west-southwest heading. The sky was clear enough to see both vehicles' leading edges, which Petty described as a dark gray or black color".
The orbiter apparently lands in a conventional manner, a la Space Shuttle, and reported sightings encompass Hurlburt AFB, Florida, Kadena AB, Okinawa, and Holloman AFB, New Mexico.
Provocative stuff. Of course, nobody in the US military has ever heard of Blackstar. ASWT says "top military space commanders apparently have never been 'briefed-in'," concluding that "most likely user is an intelligence agency" with eyes on the deployment of surveillance equipment comprising "an advanced imaging suite that features 1-metre-aperture adaptive optics with an integral sodium-ion-sensing laser".
So what's the solid evidence supporting AWST's story? As noted above, the SR-3 carrier vehicle resembles the XB-70 Valkyrie - legendary in both its technical ambitions and sheer cost.
The Ride of the Valkyrie
The XB-70 programme, initiated in 1955 by manufacturer North American, was designed to provide a very fast, long-range replacement for the B-52.
Powered by six turbojet engines to Mach 3, the XB-70 (left) was 196 feet long with a wingspan of 105 feet. Two prototypes were built at a cost of $700m a pop. The first (AV/1) made its maiden flight in 1964, with sister ship AV/2 taking to the skies in July 1965. The programme was dogged by technical problems from the start (detailed history of the project here), and ultimately doomed in June 1966 when AV/2 collided in midair with an accompanying F-104 Starfighter during a photo call flypast for the benefit of the manufacturers. Two pilots died and the aircraft was destroyed.
The Valkyrie had, however, previously reached it target velocity of Mach 3 in October 1965. The surviving AV/1 made a further 33 test flights until retirement in 1969, by which time the US military had acknowledged that sheer speed or altitude alone - which, in the case of the former, prevented the Valkyrie from performing even the most modest evasive manoeuvres - would not protect the aircraft from falling victim to Soviet ground-to-air missile technology. The case of Gary Powers, whose U-2 spyplane was brought down over the Soviet Union in 1960, made this painfully apparent.*
AWST's tech factsheet of the SR-3 reads as follows:
- A roughly 200 ft long, clipped-delta-winged planform resembling that of the North American Aviation XB-70 trisonic bomber.
- Canards that extend from the forward fuselage. These lifting surfaces may sweep both fore and aft to compensate for large centre-of-gravity changes after dropping the spaceplane, based on multiple sighting reports.
- Large, outward-canted vertical tail surfaces at the clipped-delta's wingtips.
- At least four engine exhaust ports, grouped as two well-separated banks on either side of the aircraft centerline.
- Very loud engines. One other classified military aircraft may have used the same type of powerplant.
- Operation at supersonic speeds and altitudes up to 90,000 feet.
Regarding the orbiter, AWST explains:
During the system's development cycle, two types of spaceplane orbiters may have been flown. Both were a blended wing/fuselage lifting-body design, but differed in size. The smaller version was about 60 foot to 65 foot long and may have been unmanned or carried a crew of two, some say. Industry engineers said this technology demonstrator was "a very successful program".
The larger orbiter is reportedly 97.5 foot long, has a highly swept, blended wing/body planform and a short vertical fin. This bulky fin apparently doubles as a buried pylon for conformal carriage of the spaceplane beneath the large SR-3. The "Q-bay" for transporting an optics-system pallet or other payloads may be located aft of the cockpit, with payload doors on top of the fuselage.
Outboard sections of the spaceplane's wing/body cant slightly downward, possibly for shock-wave control and compression lift at high speeds while in the atmosphere, whether on ascent or reentry. The only visible control surfaces are flap or drag-type panels on the wing's trailing edge, one section on each side of the stubby vertical fin. A relatively large spade-shaped section forward of the cockpit - which gives the orbiter a "shark-nose" appearance - may provide some pitch stability, as well.
The orbiter's belly appears to be contoured with channels, riblets or "strakelets" that direct airflow to engine inlets and help dissipate aerodynamic heating. These shallow channels may direct air to a complex system of internal, advanced composite-material ducts, according to an engineer who says he helped build one version of the orbiter in the early 1990s. Air is directed to what is believed to be aerospike engines similar to those once planned for use on the NASA/Lockheed Martin X-33.