Stalker
Lockheed Martin Skunk Works · UAV · United States of America · Modern (1992–2009)
The Lockheed Martin Stalker is an American small-class long-endurance UAV — Lockheed Martin Skunk Works's electric + hybrid-fuel-cell powered surveillance UAV + a niche product in the US Special Operations small-UAV market. Lockheed Martin Skunk Works developed the Stalker in 2006-2010 for US Special Operations Command + entered service 2006. Several hundred Stalkers have been built; the system is used by US Special Operations Command + (export-restricted) classified end-users.
The Stalker XE (current variant) uses an electric motor with hybrid solid-oxide fuel-cell power. Maximum speed 100 km/h, endurance 8 hours (XE) or 12 hours (XE Solid Oxide Fuel Cell variant), range >100 km, service ceiling 4,000 m, MTOW 6 kg, wingspan 3 m. Payload: daylight TV + FLIR gimbal + (some variants) LIDAR + signal-intelligence receivers. Launch: hand-launched or bungee-launched. Recovery: belly-landing or net. The aircraft uses a quiet electric propulsion (no audible signature at altitude) + low-radar-cross-section airframe.
Stalker service is concentrated with US Special Operations Command (USSOCOM) for long-endurance covert reconnaissance. The hybrid fuel-cell variant extends endurance to ~12 hours — well beyond electric-only competitors. Famous use scenarios (publicly disclosed): Operation Inherent Resolve counter-ISIS surveillance 2014-2019, + extended-duration border-surveillance + counter-narcotic operations. The Stalker is among very few US small-class UAVs to use hybrid fuel-cell power; the technology has since been adopted by additional Skunk Works UAVs + (in different form) civilian electric-aircraft developers. Production continues under classified contracts; specific unit counts + customer details remain undisclosed.
For Kids — a shorter, friendlier version
The Lockheed Martin Stalker is a small American spy drone. It was built by a famous team called Skunk Works. The Stalker first flew for the military in 2006.
The Stalker is very light and small. It weighs only about 6 kilograms. That is smaller than most pet dogs! Its wings stretch 3 meters wide, which is longer than a grown adult lying down.
This drone runs on a quiet electric motor. Some versions also use a special fuel cell for extra power. Because it is so quiet, people on the ground cannot hear it flying above them.
The Stalker can fly for up to 12 hours without stopping. It can reach speeds of up to 100 kilometers per hour. Soldiers launch it by hand or with a bungee cord, like a slingshot. It lands softly on its belly or in a net.
The Stalker carries special cameras that see in daylight and at night. It helps special operations soldiers gather information safely from the sky. Hundreds of these drones have been built for the American military.
Fun Facts
- The Stalker is so quiet that people on the ground cannot hear it flying overhead.
- It weighs only 6 kilograms — lighter than most backpacks full of school books.
- The Stalker's wings are 3 meters wide, longer than a tall adult lying flat on the floor.
- Some Stalker drones can fly for 12 hours straight without landing.
- Soldiers can launch the Stalker simply by throwing it into the air by hand.
- The drone can fly as high as 4,000 meters — taller than many mountains in Europe.
- The Stalker can see in total darkness using its special heat-sensing camera.
- It was designed and built by the famous Skunk Works team, known for making secret and advanced aircraft.
Kids’ Questions
How does the Stalker drone fly without making noise?
The Stalker uses a quiet electric motor instead of a loud gas engine. At high altitudes, people below cannot hear it at all. This makes it great for secret scouting missions.
How do soldiers get the Stalker into the air?
Soldiers can launch the Stalker in two ways. They can simply throw it into the air by hand. They can also use a bungee cord to fling it into the sky, a bit like a giant slingshot.
How long can the Stalker stay in the air?
The regular Stalker can fly for up to 8 hours. A special version with a fuel cell can stay up for 12 hours. That is like watching six movies back to back!
What does the Stalker do while it flies?
The Stalker carries cameras that record video during the day and at night. It helps special operations soldiers see what is happening in hard-to-reach places. Some versions can also pick up electronic signals from far away.
Variants
- Stalker XE (electric)
- 8-hour endurance pure-electric variant.
- Stalker XE SOFC (hybrid)
- 12-hour endurance solid-oxide fuel-cell variant.
Notable Operators
- US Special Operations Command (2006-present)
- Principal operator. Long-endurance covert reconnaissance.
Frequently Asked Questions
How does the solid-oxide fuel-cell power extend endurance?
The Stalker XE Solid Oxide Fuel Cell variant uses a hybrid powertrain — a small electric motor + battery for short-term peak power, + a propane-fed solid-oxide fuel cell (SOFC) generating electricity continuously at ~500°C operating temperature. SOFCs offer ~5× the energy density of equivalent batteries (kWh/kg) + extend Stalker endurance from 8 hours (pure-electric) to ~12 hours. The fuel cell is also nearly silent — unlike piston engines, there is no audible exhaust signature. The trade-off is system complexity + startup time (~15 min for the SOFC to reach operating temperature). For long-endurance covert ISR missions where audible signature + duration both matter, the SOFC hybrid is the right architecture.
Sources
See Also
- AeroVironment RQ-11 Raven — Competing US small UAV
- AeroVironment RQ-20 Puma — Competing US small UAV