Super Loki

Super Loki
Credit - via Andreas Parsch

Sounding rocket. Year: 1968. Family: Loki. Country: USA.

Larger-diameter version of single-stage Loki sounding rocket, developed originally for NASA's Marshall Spaceflight Center.

A new motor with a diameter of 102 mm replaced the original Loki, and after seperation of the payload dart the depleted motor had better ballistic characteristics, ensuring it would not land outside of the planned impact area. This sounding rocket, with both chaff and instrument payloads, continued in use into the 21st Century.

The Super Loki stable booster rocket systems was developed by Bruce Bollermann at Space Data Corporation to obtain high altitude temperature, density, and wind measurements by means of small inexpensive rocket systems which had post-burnout stable booster trajectories. These systems could be used at ranges where booster wind drift was a safety problem. The expended rocket booster impacted at a range of about 4.56 km from the launch site. These systems were developed to replace the Super Loki PWN-10A, PWN-10B, and PWN-12A at launch sites requiring either transponder or falling sphere payloads and stable booster impacts.

Manufacturer: Space Data. Launches: 641. Failures: 1. First Launch Date: 1968-11-20. Last Launch Date: 2004-09-01. Launch data is: continuing. Payload: 6.00 kg (13.20 lb). Apogee: 90 km (55 mi). Liftoff Thrust: 18.000 kN (4,046 lbf). Total Mass: 29 kg (63 lb). Core Diameter: 0.10 m (0.33 ft). Total Length: 3.16 m (10.36 ft). Span: 0.20 m (0.67 ft).

Model: PWN-10. Country: USA. Department of Defence Designation: PWN-10. Popular Name: Super Loki Datasonde.

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.

Specifications

Note: 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

Main Sources

[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

Model: PWN-11. Country: USA. Department of Defence Designation: PWN-11. Popular Name: Super Loki Datasonde.

Historical Essay © Andreas Parsch

Space Data PWN-11 Super Loki Datasonde

The PWN-11A uses the same Super Loki rocket motor and temperature measuring instrument package as the PWN-10 probe (q.v. for further details), but has a smaller and lighter dart without a transponder unit. Therefore the PWN-11A can reach a slightly higher apogee (80 km (50 miles) vs. 70 km (43 miles) of the PWN-10) but requires a tracking radar to get wind speed and direction data.

In the late 1990s, the PWN-11 (also known as Super Loki Rocketsonde) was still used by NASA Wallops for high-altitude weather recordings. The probe was then usually referred to as PWN-11D Datasonde(r), but this is a non-military designation (the suffix "D" was possibly chosen to mean "Datasonde").

Specifications

Note: Data given by several sources show slight variations. Figures given below may therefore be inaccurate!

Data for PWN-11A:

Length (incl. booster)	3.16 m (10 ft 4.5 in); dart: 1.16 m (45.7 in)
Diameter	Booster: 10.2 cm (4 in); dart: 4.0 cm (1.58 in)
Finspan	Booster: 20.3 cm (8 in); dart: 11.7 cm (4.62 in)
Weight (incl. booster)	29 kg (64 lb); dart: 6 kg (13.2 lb)
Speed	?
Ceiling	80 km (50 miles; 260000 ft)
Propulsion	Aero Dyne SR110-AD-1 Super Loki solid-fuel rocket; 25 kN (5520 lb) for 2.1 s

Main Sources

Model: PWN-12. Country: USA. Department of Defence Designation: PWN-12. Popular Name: Super Loki Robin.

Historical Essay © Andreas Parsch

Space Data PWN-12 Super Loki ROBIN

The PWN-12A is another sounding rocket using the Super Loki booster of the PWN-10 and PWN-11. It uses a dart with a ROBIN (Rocket Balloon Instrument) Inflatable Falling Sphere payload. At an apogee of about 115 km (70 miles), the dart releases an ML-568/AM metalized mylar balloon, which is inflated to 1 m (3.3 ft) diameter and 12 hPa pressure. While it is slowly descending back to earth, the balloon is tracked by a high-precision radar (e.g. AN/FPS-10) on the ground. Minimum tracking altitude is about 30 km (18 miles), where the ambient pressure will cause the balloon to collapse. Using the balloon's known mass and volume, the radar track can be used to calculate atmospheric data like wind speed/direction and air density. The latter can then be used to calculate air pressure and temperature.

Other than the telemetry-equipped PWN-10 and PWN-11 probes, the PWN-12A ROBIN requires a high-precision radar to get air temperature data. However, its maximum altitude and temperature measurement ranges are greater than that of the datasondes. PWN-12A rockets (also known as Super Loki Inflatable Sphere) are still used today on NASA and military stations for regular high-altitude weather probing.

Specifications

Note: Data given by several sources show slight variations. Figures given below may therefore be inaccurate!

Data for PWN-12A:

Length (incl. booster)	3.16 m (10 ft 4.5 in); dart: 1.16 m (45.7 in)
Diameter	Booster: 10.2 cm (4 in); dart: 4.0 cm (1.58 in)
Finspan	Booster: 20.3 cm (8 in); dart: 11.7 cm (4.62 in)
Weight	?
Speed	?
Ceiling	115 km (70 miles; 380000 ft)
Propulsion	Aero Dyne SR110-AD-1 Super Loki solid-fuel rocket; 25 kN (5520 lb) for 2.1 s

Main Sources

[1] Richard B. Morrow, Mitchell S. Pines: "Small Sounding Rockets", Small Rocket Press, 2000
[2] "DOD 4120.15-L: Model Designation of Military Aerospace Vehicles", Department of Defense, 1974
[3] Upper Air Instrumentation Research Projects Website, NASA, 1997
[4] Edward J. Hopkins: "Meteorological Rockets", 1996

Super Loki Chronology

1968 November 20 - 22:45 GMT - Launch Site: Cape Canaveral. Launch Vehicle: Super Loki.

Aeronomy mission Nation: USA. Apogee: 75 km (46 mi). References: 1592.

1968 December 19 - 19:10 GMT - Launch Site: Cape Canaveral. Launch Vehicle: Super Loki.

Aeronomy mission Nation: USA. Apogee: 75 km (46 mi). References: 1592.

1968 December 19 - 18:00 GMT - Launch Site: Cape Canaveral. Launch Vehicle: Super Loki.

Aeronomy mission Nation: USA. Apogee: 75 km (46 mi). References: 1592.

1969 January 25 - 03:00 GMT - Launch Site: White Sands. Launch Vehicle: Super Loki.

Meteorological sphere aeronomy mission Nation: USA. Agency: USA. Apogee: 126 km (78 mi). References: 1550.

1969 January 27 - 22:00 GMT - Launch Site: White Sands. Launch Vehicle: Super Loki.

Meteorological sphere aeronomy mission Nation: USA. Agency: USA. Apogee: 127 km (78 mi). References: 1550.

1969 February 19 - 19:30 GMT - Launch Site: White Sands. Launch Vehicle: Super Loki.

Meteorological sphere aeronomy mission Nation: USA. Agency: USA. Apogee: 120 km (70 mi). References: 1550.

1969 April 20 - 04:15 GMT - Launch Site: White Sands. Launch Vehicle: Super Loki.

Meteorological sphere aeronomy mission Nation: USA. Agency: USA. Apogee: 120 km (70 mi). References: 1550.

1969 May 11 - 07:00 GMT - Launch Site: White Sands. Launch Vehicle: Super Loki.

Meteorological sphere aeronomy mission Nation: USA. Agency: USA. Apogee: 126 km (78 mi). References: 1550.

1969 June 27 - Launch Site: Cape Canaveral. Launch Complex: LC43. Launch Vehicle: Super Loki.

Aeronomy mission Nation: USA. Agency: NASA?. Apogee: 91 km (56 mi). References: 1956.

1970 April 10 - 20:20 GMT - Launch Site: Cape Canaveral. Launch Vehicle: Super Loki.

Aeronomy mission Nation: USA. Apogee: 75 km (46 mi). References: 1592.

1970 April 11 - 21:43 GMT - Launch Site: Cape Canaveral. Launch Vehicle: Super Loki.

Aeronomy mission Nation: USA. Apogee: 75 km (46 mi). References: 1592.

1970 October 6 - 18:40 GMT - Launch Site: Cape Canaveral. Launch Vehicle: Super Loki. LV Configuration: Super Loki AFCRL 70-1.

Test mission Nation: USA. Agency: USAF. Apogee: 73 km (45 mi). References: 1592.

1970 October 7 - 16:00 GMT - Launch Site: Cape Canaveral. Launch Vehicle: Super Loki. LV Configuration: Super Loki AFCRL 70-2.

Test mission Nation: USA. Agency: USAF. Apogee: 72 km (44 mi). References: 1592.

1970 October 8 - 15:15 GMT - Launch Site: Cape Canaveral. Launch Vehicle: Super Loki. LV Configuration: Super Loki AFCRL 70-4.

Test mission Nation: USA. Agency: USAF. Apogee: 74 km (45 mi). References: 1592.

1970 October 8 - 13:00 GMT - Launch Site: Cape Canaveral. Launch Vehicle: Super Loki. LV Configuration: Super Loki AFCRL 70-3.

Test mission Nation: USA. Agency: USAF. Apogee: 78 km (48 mi). References: 1592.

1970 October 8 - 16:23 GMT - Launch Site: Cape Canaveral. Launch Vehicle: Super Loki. LV Configuration: Super Loki AFCRL 70-5.

Test mission Nation: USA. Agency: USAF. Apogee: 75 km (46 mi). References: 1592.