In the early 1970s, a division of AiResearch Manufacturing Co. in Phoenix, Arizona, crafted the Garrett STAMP.
But first, what is VTOL?
A Vertical Take-off and Landing (VTOL) aircraft can launch and alight vertically, eliminating the need for a runway.
This category embraces various aircraft such as helicopters, fixed-wing aircraft with thrust-vectoring, and other hybrids with powered rotors like cyclogyros/cyclocopters and gyrodynes.
Many VTOL aircraft can also operate in different modes, including CTOL (conventional take-off & landing), STOL (short take-off & landing), and STOVL (short take-off & vertical landing).
Some, mainly helicopters, can solely operate as VTOL, as they lack the landing gear for taxiing, making VTOL a subset of V/STOL (vertical or short take-off & landing).
Certain lighter-than-air aircraft also qualify as VTOL as they can hover and maneuver with vertical profiles.
Electric VTOLs (eVTOLs) are under development, leveraging advanced autonomous flight control and Mobility-as-a-Service (MaaS) technologies.
These developments aim to offer advanced air mobility (AAM), covering on-demand air taxis, regional air mobility, freight, and personal air vehicles (PAVs).
Currently, in military service, VTOL aircraft types include tiltrotor aircraft, like the Bell Boeing V-22 Osprey, and thrust-vectoring airplanes, like the Harrier family and the new F-35B Lightning II Joint Strike Fighter (JSF).
In the civilian realm, only helicopters are in widespread use, with other commercial VTOL types in development. Generally, where possible, VTOL aircraft capable of STOVL use it, as it typically improves takeoff weight, range, or payload compared to pure VTOL.
The Garrett STAMP (Small Tactical Aerial Mobility Platform)
A This Small Tactical Aerial Mobility Platform was a prototype for the United States Marine Corps. It accommodated two people, maneuvering with a ducted fan like the Harrier.
However, unlike the Harrier, it lacked wings, relying solely on fan thrust for lift.
Consequently, its projected range was 30 miles, traveling at 75 mph. It utilized a Garrett TSE-231 turbine, typically found in helicopters, producing 1050 pounds of thrust at 6000 rpm.
Read More: Williams X-Jet: – The Personal VTOL ‘Aircraft’
The cockpit, adapted from an OH-6 helicopter, housed two individuals. The prototype underwent successful tethered flight tests on December 21, 1973, at the Marine Corps Air Station El Toro in California.
Its rival in the STAMP program was the Williams Aerial Systems Platform (WASP) from Williams International, a single-person craft with an open cockpit.
Half a Million
This bizarre vehicle is the Garrett STAMP (Small Tactical Aerial Mobility Platform), a kind of two-seater “flying jeep” developed by Garrett Corp. (Phoenix, AZ) in the early seventies.
The project—costing approximately $500,000—began in December 1972 under the auspices of the US Marine Corps, eager to explore the concept of a light VTOL (Vertical Takeoff and Landing) vehicle with vectored thrust.
The design team consisted of a dozen Garrett engineers, overseen by the Naval Weapons Center in China Lake (California).
To expedite and simplify the construction of the prototype, while also reducing costs, Garrett chose to use the fuselage and cockpit from the light observation helicopter Hughes OH-6A Cayuse.
It was stripped of everything deemed superfluous, such as the tail, rotors, and original propulsion apparatus. The OH-6 was chosen due to its robust, yet compact and light, frame.
The first flight took place on December 21, 1973, at the Marine Corps air base in El Toro, California.
The propulsion of the STAMP was entrusted to a 474 hp Garrett TSE-231 turboshaft, which provided about half a ton of thrust at 6000 rpm through two large rectangular ducts located on each side of the vehicle.
Based on the “ducted fan” principle (see also the Harrier), the STAMP was completely dependent on the thrust generated by the turboshaft, as it had no wings.
The air was drawn in by the large fan located at the rear, while the airflow, after cooling the exhaust gases, was channeled along with them through the side ducts.
There is a pretty cool report here on VTOL designs Mil.Report
The dimensions were as follows: 250 cm in length, 180 cm in height, and 180 cm in width, while the empty weight was around 300 kg.
The STAMP could reach a maximum speed of about 120 km/h, with an estimated range of around 50 km.