S-TEC Sentry
A 1980s US battlefield mini-UAV with autopilot heritage.
The S-TEC Sentry is a battlefield mini-UAV, comparable to the BAI Dragon drone, that was introduced in 1986 by S-TEC Systems of Texas, now part of DRS Unmanned Technologies. The company’s primary business is producing autopilots for civilian aircraft, and small UAVs were a natural offshoot of that work. The Sentry is built from carbon composite and Kevlar, powered by a 19.5 kW (26 hp) piston engine in a tractor configuration, and visually resembles an Exdrone with a twin-boom raised tail. It launches from a wheeled dolly or pneumatic catapult and recovers via parasail or skid landing gear. Over 130 units have been sold. In an unusual test, S-TEC experimented with carrying the BLU-108 Sensor Fuzed Weapon anti-armor submunition on the Sentry. After release, the cylindrical SFW deploys a small parachute to orient itself, then fires four "skeet" projectiles in four directions. Each skeet uses an infrared sensor to detect when it passes over an armored vehicle, then fires a penetrator slug downward to punch through the top armor. S-TEC has partnered with TRW Corporation in the United States and IAI of Israel to market the UAV internationally.
Quick Facts
- Aircraft Type
- Reconnaissance UAV
- National Origin
- United States
- Manufacturer
- S-TEC
- First Flight
- 1986
Facts from the source article.
Lore & Background
The S-TEC Sentry was introduced in 1986, and over 130 units have been sold since that time. Its design resembles an Exdrone with a twin-boom raised tail. The airframe is built of carbon composition and Kevlar, and is powered by a 19.5 kW (26 hp) piston engine in a tractor configuration. Launch is accomplished via a wheeled dolly or pneumatic catapult, and recovery is via parasail or on skid landing gear. S-TEC has teamed with TRW Corporation in the US and IAI of Israel to sell UAVs on the international market. In an interesting experiment, the company has experimented with carriage of the BLU-108 Sensor Fuzed Weapon (SFW) anti-armor submunition on the Sentry. After release in a target area, the cylindrical SFW pops out a small parachute to orient itself and then fires out four 'skeet' projectiles in four directions. The skeets have an infrared sensor to detect when they are flying over the top of an armored vehicle, and then fire a penetrator slug straight down to punch through the top armor.
Reader's Guide
The S-TEC Sentry represents a niche but significant entry in the history of small battlefield UAVs. Developed by a company whose primary expertise was in civil aviation autopilots, the Sentry demonstrated how existing technology could be adapted for military reconnaissance roles. Its sales of over 130 units indicate a modest but sustained market presence. The experimental integration of the BLU-108 Sensor Fuzed Weapon submunition highlights an early attempt to give a mini-UAV an anti-armor strike capability, a concept that would later become more common. The partnership with TRW and IAI for international sales reflects the global interest in such systems during the late Cold War and post-Cold War periods. While not as widely known as some contemporaries, the Sentry's use of carbon composite and Kevlar construction, along with its twin-boom tail configuration, placed it within the technological mainstream of its era. Its legacy lies in showing that a company focused on autopilots could successfully branch into complete UAV systems.
Did You Know?
- The S-TEC Sentry is built of carbon composition and Kevlar.
- Recovery can be via parasail or on skid landing gear.
More in Unmanned Aerial Vehicles by Country, Part 2 1-24
Spotted an error? Know more?
Reader corrections go straight into our review queue. Suggest an edit · How this site is sourced