AKA: Super Loki Datasonde.
In the late 1960s, the USAF wanted a version of the instrumented Loki-Dart PWN-8 with a transponder integrated into the payload to allow a ground tracking technique other than radar. The "starute" (square-shaped metalized parachute structure) was also to be of greater diameter to compensate the higher payload weight. All this required a larger dart, and in turn a more powerful booster. For this purpose, Space Data Corporation developed the Super Loki booster.
Historical Essay © Andreas Parsch
Space Data PWN-10 Super Loki Datasonde
In the late 1960s, the USAF wanted a version of the instrumented Loki-Dart (PWN-8) with a transponder integrated into the payload to allow a ground tracking technique other than radar. The "starute" (square-shaped metalized parachute structure) was also to be of greater diamater to compensate the higher payload weight. All this required a larger dart, and in turn a more powerful booster. For this purpose, Space Data Corporation developed the Super Loki booster. The significantly increased power more than made up for the heavier dart, and could be used to increase overall safety of the system by adding a weight to the booster-dart adapter. This made the booster much more stable after burnout and separation, preventing a tumbling descent on an uncontrolled trajectory. Super Loki rockets are launched from a pad-mounted helical rail-gun launcher, which can be adjusted in azimuth and elevation. The spiral rails impose a stabilizing spin on the rocket during launch.
The USAF used several Super Loki boosted meteorological probes, the first of which was the PWN-10A. It carried a dart with a temperature sensor, a telemetry transmitter, and a transponder. The instrument package transmitted temperature data, and received and transmitted ranging data for accurate tracking to determine wind speed and direction. The PWN-10B was identical except that the ranging receiver was not included in the payload (therefore requiring a powerful tracking radar). From about 1970, the PWN-10 replaced the much more expensive PWN-6 Kitty (Arcas) and the less capable PWN-8 as the Air Force's standard meteorological sounding rocket.
Other derivatives of the Super Loki-Dart used by the USAF were the PWN-11 and PWN-12 probes. In the late 1990s, the PWN-10 (also known as the Super Loki Transpondersonde) was still used by NASA Wallops for high-altitude weather recordings. The probe was then referred to as PWN-10D Datasonde(r), but this is a non-military designation (the suffix "D" was possibly chosen to mean "Datasonde"). Current prime contractor for all Super Loki related rockets is Orbital Sciences, which acquired Space Data in 1991.
SpecificationsNote: Data given by several sources show slight variations. Figures given below may therefore be inaccurate!
Data for PWN-10A:
Length (incl. booster) | 3.34 m (10 ft 11.4 in); dart: 1.32 m (51.9 in) |
Diameter | Booster: 10.2 cm (4 in); dart: 5.40 cm (2.125 in) |
Finspan | Booster: 20.3 cm (8 in); dart: 15.7 cm (6.2 in) |
Weight (incl. booster) | 31 kg (68 lb); dart: 8.1 kg (18 lb) |
Speed | 5800 km-h (3600 mph) |
Ceiling | 70 km (43 miles; 230000 ft) |
Propulsion | Aero Dyne SR110-AD-1 Super Loki solid-fuel rocket; 25 kN (5520 lb) for 2.1 s |
[1] Richard B. Morrow, Mitchell S. Pines: "Small Sounding Rockets", Small Rocket Press, 2000
[2] Peter Alway: "Rockets of the World", Saturn Press, 1999
[3] "DOD 4120.15-L: Model Designation of Military Aerospace Vehicles", Department of Defense, 1974
[4] Upper Air Instrumentation Research Projects Website, NASA, 1997
[5] Edward J. Hopkins: "Meteorological Rockets", 1996