Lockheed Polecat UAV Crashes

Lockheed have lost the only airframe of their experimental flying wing P-175 "Polecat" UAV after it crashed in the Nevada Test Range on 18th December 2006.

The Skunkworks have revealed that the technology demonstrator crashed after an "irreversible unintentional failure in the flight termination ground equipment, which caused the aircraft's automatic fail-safe flight termination mode to activate". Apparently an accidental loss of a $30 million piece of kit.

The Polecat was built to fly at 60,000 ft but never got over 15,000 and it appears that the aircraft only about 5 flights.

Although Lockheed are said to be still laising with the Pentagon with regard to building more UAVs, this is surely a huge set-back to a company which seem to be trailing behind in terms of UAV and flying wing technology.

F-35 Makes Further Flights

The F-35 made its second test flight on the 8th January, lifting its landing gear for the first time and climbing up to 20,000 feet. It also made its third flight on the 10th January.

Click on the picture above for an impressive hi-res version.

Flexible Winged Aircraft Receives X-53 Designation

The Active Aeroelastic Wing (AAW) aircraft is a joint project between NASA Dryden, the Air Force Research Laboratory and the Boeing Phantom Works. The test plane, a modified F/A-18, has a digital flight control system which allows the wings to naturally twist and morph for better manoeuvrability during high speed flight.

Instead of having standard stiff control surfaces the aircraft has flexible leading and trailing edges. These take advantage of the aeroelastic effects that are often detrimental to standard flight. In my opinion the technology could also reduce radar reflections, in turn increasing stealth, from the joins on normal control surfaces.

Obtaining the X-53 name is a step forward as it demonstrates the importance of the project and also makes it more visible to the public and industry insiders. In the future this technology could be used on morphing unmanned aerial vehicles and strike bombers.

F-35 Lightning II Makes First Flight

At 12:44 on the 15th December 2006 the Lockheed Martin F-35 Lightning II fighter took off for the first time from Fort Worth, Texas. Two F-16s and a F/A-18 acted as chase planes during the first flight which begins one of the most comprehensive test schedules ever undertaken, lasting 6 years and 12,000 flight hours performed by 15-20 test planes.

Chief test pilot, Jon Beesley said after the flight, "The Lightning II performed beautifully."
Early reports suggested that Beesley landed the plane after 32 minutes of a planned hour flight, yet the official LockMart press release doesn't mention this and an early landing during the first flight could have been caused by one of thousands of minor faults.

The F-35 that flew on Friday was a conventional takeoff and landing (CTOL) variant, designed to perform on normal runways. Two other variants are in the pipeline, the short takeoff and vertical landing (STOVL) designed to takeoff from small ships and a carrier variant (CV) for catapult launches and cable recoveries. This test plane also used one of two engines designed for the F-35, the Pratt & Whitney F135, rather than the GE Rolls-Royce Fighter Engine Team F136.

More photos can be found here: http://www.accuconference.com/f35.html%5C

Northrop & GD Underwater Express

This subject is strictly off-topic for this blog (destined for Georges View from Above) but I found it interesting anyway.

DARPA have awarded contracts to Northrop Grumman and General Dynamics to develop a high speed underwater craft using supercavitating technology. For more information on supercavitation check http://en.wikipedia.org/wiki/Supercavitation, but the basics are that a craft or object can be specially shaped so that, at high enough speeds, it vapourises the water it is travelling through to create a bubble of gas around itself. Drag underwater is about 1000 times that in air and supercavitation gets around this drag by allowing a craft to effectively fly underwater through a bubble of gas which travels at the same speed as the craft.

DARPA are hoping to create an underwater supercavitating craft (as far as I can see the first of its kind) to transport valuable cargo or small amounts of troops at very high speeds. Apparently the craft may share similarities with a Russian supercavitating torpedo, the Shkval, but with a retracting cavitating nose-cone. The Shkval could travel at up to 230 mph.

If the project progresses a scale model of the Underwater Express will be built with approximate diameter of 8ft and weight of 60 tonnes. Research is currently being performed at the Naval Undersea Warfare Center (Rhode Island) and the Space and Naval Warfare Systems Center (San Diego).