They were the mischievous creatures blamed for causing mechanical failures and faults on aircraft during World War Two and later the destructive monsters in a hit film franchise.

So Gremlins might not seem like the first choice for a fleet of robotic aircraft being developed by the US military.

But the US Defense Advanced Research Projects Agency has given the go ahead for four firms to begin building the craft.

Darpa said the program has been deliberately named Gremlins after the imps that British pilots during Wold War Two adopted as their good luck charms.

Composite Engineering, Dynetics, General Atomics Aeronautical Systems and Lockheed Martin will develop craft

Named for the imaginary, mischievous imps that became the good luck charms of many British pilots during World War II, the program envisions launching groups of UASs from existing large aircraft such as bombers or transport aircraft - as well as from fighters and other small, fixed-wing platforms - while those planes are out of range of adversary defenses.

When the gremlins complete their mission, a C-130 transport aircraft would retrieve them in the air and carry them home, where ground crews would prepare them for their next use within 24 hours.

The gremlins' expected lifetime of about 20 uses could provide significant cost advantages over expendable systems by reducing payload and airframe costs and by having lower mission and maintenance costs than conventional platforms, which are designed to operate for decades.

'We've assembled a motivated group of researchers and developers that we believe could make significant progress toward Gremlins' vision of delivering distributed airborne capabilities in a robust, responsive and affordable manner,' said Dan Patt, DARPA program manager. 

'These teams are exploring different, innovative approaches toward achieving this goal and are rolling up their sleeves for the hard work ahead.'

The idea is to replace the expensive and increasingly vulnerable multi-function combat aircraft which currently perform a range of different missions.

Instead they propose deploying from the air smaller unmanned aircraft, each with different capabilities, to perform a mission before retrieving them mid-air so they can be used again.

Not only would the concept remove the risk to pilots by keeping them out of the front line but it would also drastically reduce the cost of each aircraft.

Darpa said the program has been deliberately named Gremlins after the imps that British pilots during Wold War Two adopted as their good luck charms.

This is because they are hoping to the 'feasibility of conducting safe, relatable operations with multiple air-launched unmanned drones'.

Dan Patt, program manager at Darpa, said: 'Our goal is to conduct a compelling proof-of-concept flight demonstration that could employ intelligence, surveillance and reconnaissance (ISR) and other modular, non-kinetic payloads in a robust, responsive and affordable manner.'

Darpa says the Gremlin drones would have a lifetime of around 20 uses, fitting somewhere between missiles and conventional aircraft.

The Gremlins would be launched in mid-air from larger aircraft and then retrieved in the same way.

The agency is hoping to build on its automated mid-air refuelling technology alongside the sea based platforms for capturing drones as they come into land.

Mr Patt said: 'We wouldn't be discarding the entire airframe, engine, avionics and payload with every mission, as is done with missiles.

'But we also wouldn't have to carry the maintainability and operational cost burdens of today's reusable systems, which are meant to stay in service for decades.'

Darpa is now inviting military engineers and academics to suggest solutions that will allow the drones to be launched and recovered mid-flight along with navigation and flight control systems.

In its briefing, the agency said it hopes that by using cheap drone aircraft it would be possible to overwhelm the increasingly sophisticated defences of enemies.

It said: 'As part of a future concept of operations, it is envisioned that instead of using conventional, monolithic systems to conduct missions in denied environments, multiple platforms with coordinated and distributed warfighting functions can be employed to saturate adversary defenses while achieving mission objectives.

'Within this concept of operations, a Gremlins system would provide options for delivering small Intelligence, Surveillance, and Reconnaissance (ISR) and other non‐kinetic payloads to the battlespace in a manner that is robust and responsive.

'Responsiveness is achieved through the use of conventional aircraft hosts to transport and launch a volley of gremlins from stand‐off ranges.

'Furthermore, by scaling up the number of systems engaged in operations, the impact of a loss of any individual gremlin is reduced.'