| P-791 | |
|---|---|
 Lockheed Martin P-791 | |
| General information | |
| Type | Hybrid airship |
| National origin | United States |
| Manufacturer | Lockheed Martin |
| Status | Prototype |
| Number built | 1 |
| History | |
| First flight | 31 January 2006 |
The Lockheed Martin P-791 is an experimental aerostatic and aerodynamic hybrid airship developed by Lockheed Martin. The first flight of the P-791 took place on 31 January 2006 at the company's flight test facility at United States Air Force Plant 42 in Palmdale, CA. [1] [2]
The P-791 has a tri-hull shape, with disk-shaped cushions on the bottom for landing. As a hybrid airship, part of the weight of the craft and its payload are supported by aerostatic (buoyant) lift and the remainder is supported by aerodynamic lift. The combination of aerodynamic and aerostatic lift is an attempt to benefit from both the high speed of aerodynamic craft and the lifting capacity of aerostatic craft. [3]
The P-791 was designed as part of the U.S. Army's Long Endurance Multi-intelligence Vehicle (LEMV) program, but lost the program's competition to Northrop Grumman's HAV-3 design. The P-791 was modified to be a civil cargo aircraft under the name SkyTug, with a lift capability of 20 short tons (18,000 kg) and plans to scale larger. [4]
In March 2016, Straightline Aviation signed a Letter of intent for 12 LMH1 airships, valued at $480 million. [5]
In 2014, Hybrid Enterprises from Atlanta, Georgia entered into an agreement with Lockheed Martin to market and sell the commercial LMH-1 Hybrid Aircraft built by Lockheed, based on the technology demonstrated by the P-791. [6]
At the Paris Air Show in June 2015, Lockheed Martin announced that all required FAA certification planning steps were complete, and Hybrid Enterprises was accepting orders. [7] The LMH1 would initially transport 20 tonnes of cargo or 19 passengers, plus 2 crew members, with deliveries beginning in 2018. [8] In September 2016, plans were announced to operate the LMH-1 craft in Alaska. [9]
In September 2017 it was announced that the first flight of the LMH-1 was being delayed to 2019. [10]
In May 2023, Lockheed Martin announced the transfer of intellectual property and assets related to their airship business, and the LMH-1, to a new company, called AT2 Aerospace, which would continue the development of the LMH-1 as the Z1 hybrid airship. [11]
The Lockheed Martin LMZ1M is the follow on to the P-791 test vehicle. [12] [13]
An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or the dynamic lift of an airfoil, or, in a few cases, direct downward thrust from its engines. Common examples of aircraft include airplanes, rotorcraft, helicopters, airships, gliders, paramotors, and hot air balloons. Part 1 of Subchapter A of Chapter I of Title 14 of the U. S. Code of Federal Regulations states that aircraft "means a device that is used or intended to be used for flight in the air."
A non-rigid airship, commonly called a blimp (/blɪmp/), is an airship (dirigible) without an internal structural framework or a keel. Unlike semi-rigid and rigid airships, blimps rely on the pressure of their lifting gas and the strength of the envelope to maintain their shape. Blimps are known for their use in advertising, surveillance, and observation due to their maneuverability, slow speeds and steady flight capabilities.
An airship, dirigible balloon or dirigible is a type of aerostat (lighter-than-air) aircraft that can navigate through the air flying under its own power. Aerostats use buoyancy from a lifting gas that is less dense than the surrounding air to achieve the lift needed to stay airborne.
Flight or flying is the motion of an object through an atmosphere, or through the vacuum of outer space, without contacting any planetary surface. This can be achieved by generating aerodynamic lift associated with gliding or propulsive thrust, aerostatically using buoyancy, or by ballistic movement.
A lifting body is a fixed-wing aircraft or spacecraft configuration in which the body itself produces lift. In contrast to a flying wing, which is a wing with minimal or no conventional fuselage, a lifting body can be thought of as a fuselage with little or no conventional wing. Whereas a flying wing seeks to maximize cruise efficiency at subsonic speeds by eliminating non-lifting surfaces, lifting bodies generally minimize the drag and structure of a wing for subsonic, supersonic and hypersonic flight, or spacecraft re-entry. All of these flight regimes pose challenges for proper flight safety.
Thrust vectoring, also known as thrust vector control (TVC), is the ability of an aircraft, rocket or other vehicle to manipulate the direction of the thrust from its engine(s) or motor(s) to control the attitude or angular velocity of the vehicle.
An aerostat or lighter-than-air aircraft is an aircraft that relies on buoyancy to maintain flight. Aerostats include the unpowered balloons and the powered airships.
The Aereon 26 was an experimental aircraft developed to investigate lifting body design with a view to using its shape to create hybrid designs, part airship, part conventional aircraft. It was powered by a piston engine, driving a pusher propeller, and generated lift through the aerodynamics of its lozenge-shaped fuselage.
A hybrid airship is a powered aircraft that obtains some of its lift as a lighter-than-air (LTA) airship and some from aerodynamic lift as a heavier-than-air aerodyne.
The Walrus HULA project was a DARPA-funded experiment to create an airship capable of traveling up to 12,000 nautical miles in range, while carrying 500–1000 tons of air cargo. In distinct contrast to earlier generation airships, the Walrus HULA would be a heavier-than-air vehicle and would generate lift through a combination of aerodynamics, thrust vectoring, and gas buoyancy generation and management.
SkyCat is a class of proposed heavy-lift hybrid airships which derive more than half of their lift by helium buoyancy and the balance via aerodynamic lift produced by aerodynamic shaping. The SkyCat design incorporates hover cushion technology in place of wheels, allowing craft to take off and land anywhere, including remote regions without need for airports or sophisticated forward based infrastructure.
Aeros Corp is an American manufacturer of airships based in Los Angeles, California. It was founded in 1993 by the current CEO and chief engineer, Igor Pasternak, who was born in Soviet Kazakhstan, raised in Soviet Ukraine, and moved to the U.S. after the Soviet collapse to build airships there. It currently employs more than 100 workers.
Airship Industries was a British manufacturers of modern non-rigid airships (blimps) active under that name from 1980 to 1990 and controlled for part of that time by Alan Bond. The first company, Aerospace Developments, was founded in 1970, and a successor, Hybrid Air Vehicles, remains active as of 2022. Airship Industries itself was active between 1980 and 1990.
The Hybrid Air Vehicles Airlander 10 is a hybrid airship designed and built by British manufacturer Hybrid Air Vehicles (HAV). Comprising a helium airship with auxiliary wing and tail surfaces, it flies using both aerostatic and aerodynamic lift and is powered by four diesel engine-driven ducted propellers.
The AeroLift CycloCrane was a unique US hybrid airship which adopted helicopter derived airfoil control for low speed flight manoeuvring by spinning on its axis. It was intended to be a heavy load lifter, initially aimed at the Canadian logging industry. A proof of concept vehicle flew at times during the 1980s, but no large production aircraft were built.
Hybrid Air Vehicles (HAV) Limited is a British limited company and a British manufacturer of hybrid airships, though none have been built since the crash of its last demonstrator in Nov 2017. These aircraft use both aerodynamics and lighter-than-air (LTA) technology to generate lift, potentially allowing the vehicle to stay aloft for several weeks.
The Aereon Dynairship is a conceptual large hybrid airship developed by the Aereon Corporation for civilian and military cargo transport.
The Nimbus EosXi is an Italian unmanned aerial vehicle (UAV) designed for civilian use, developed and manufactured by NIMBUS Srl.
{{cite web}}: CS1 maint: numeric names: authors list (link)The airships are considered "hybrid" in nature because they apply both aerostatic (i.e., buoyant) and aerodynamic technologies to achieve lift, thereby exceeding dirigibles in speed and planes in economy.
press release by Lockheed Martin Aeronautics