Friday, 6 May 2011

Top Secret Weapon US Navy SEALs In Osama Laden Raid Revealed

The crash of a helicopter involved in the raid on Osama bin Laden's Pakistani hideout has prompted intense speculation about whether the aircraft was specially modified to fly stealthily—and whether its remains could offer hostile governments clues to sensitive U.S. military technology.

According to U.S. officials, two Black Hawk helicopters carrying Navy SEALs landed in the compound in Abbottabad, while two other helicopters circled overhead. One Black Hawk was disabled during the landing, and had to be destroyed by the commandos.

However, remnants of the helicopter, including a nearly intact piece of its tail, suggested that the aircraft involved in the raid wasn't the typical MH-60 Black Hawk flown by special-operations forces. Aviation experts who scrutinized photos of the scene say the tail had unusual features that suggested the helicopter had been extensively modified to fly quietly, while appearing less visible to radar.

Is This the Navy's Secret Helicopter?

The U.S. military has tried in the past to build a stealth helicopter, but has kept secret if it has indeed succeeded.

The wreckage in Abbottabad appeared to have exotic coatings and distinct surfaces and edges reminiscent of stealth aircraft such as the B-2 bomber and the F-22 fighter, aviation experts say. Equally important, they pointed to an unusual dishpan-shaped cover over the tail rotor, perhaps designed to make the aircraft quieter.

"The odds are fair—based on my knowledge of the subject area—the vast majority of the special MH-60s aircraft were purpose-built to make those aircraft as stealthy as they could possibly be," said Jay Miller, an author who has written extensively about stealth aircraft.

Mr. Miller said the remnants of the aircraft suggested extensive use of nonmetallic composite parts, which reflect less radar energy. Likewise, he said the tail's remains suggested that it was designed to shroud or mask metal parts, which are much more visible to radar.

In addition, experts said the tail rotor's design suggested an effort to reduce the "acoustic signature" of the helicopters—in other words, to make them fly more quietly.

Rex Rivolo, a former Black Hawk aviator and helicopter expert, said the distinctive noise of a helicopter's rotor blades is "the signature that gives you away."

Mr. Rivolo said the military had studied a number of methods for reducing helicopter noise, including pairing helicopters with unmanned aircraft to cancel out noise.

But he was skeptical about how far those efforts had advanced.

"It's really never materialized," he said. " 'Whisper mode' just doesn't exist."

The U.S. Army spent billions developing the Comanche, a stealth-helicopter project canceled in 2004. Two prototypes were developed, but Comanches were never fielded because of their high price.

Stealth features would have been particularly important in the bin Laden mission: The Navy assault team presumably wanted to give those in the compound as little warning as possible.

In addition, the commandos entered Pakistani air space without permission of the Pakistani authorities; the longer it took for the Pakistani military to realize the helicopters were there, the less likely they would interfere in the U.S. mission.

The recovery of the tail by the Pakistanis raised questions about whether some of the unique technology may have fallen into the wrong hands.

Rep. Howard "Buck" McKeon (R., Calif.), the chairman of the House Armed Services Committee, told reporters Thursday he was unaware of any efforts to retrieve the tail. He said there wasn't much left of the aircraft after the SEALs blew it up, said a staffer who was present. The Pentagon declined to comment on the downed helicopter.

As experts have gotten a look at photos of the pieces of a U.S. helicopter left behind at the compound where Osama bin Laden was killed, they've come to the conclusion that commandos were using a stealth version of the famous Black Hawk, Army Times and IHS Jane's report.

Jane's says that:

"Following the raid on 1 May only the tail section of the helicopter remained — the main body having been destroyed in situ by US special forces — but aspects of its design do not tally with the generally held belief that Sikorsky MH/UH-60 Black Hawk-type helicopters were used in the mission.

"Specifically, the tail rotor of the crashed helicopter has a five-bladed assembly, whereas the Black Hawk tail rotor has four blades. Also, where the Black Hawk's vertical tail section tapers towards the top, the helicopter lost in the raid has a vertical tailplane than has an even chord from top to bottom capped off with what appears to be a large aerodynamic surface."

And Army Times reports that:

"The helicopters that flew the Navy SEALs on the mission to kill Osama bin Laden were a radar-evading variant of the special operations MH-60 Black Hawk, according to a retired special operations aviator.

"The helicopter's low-observable technology is similar to that of the F-117 Stealth Fighter the retired special operations aviator said. 'It really didn't look like a traditional Black Hawk,' he said. It had 'hard edges, sort of like an ... F-117, you know how they have those distinctive edges and angles — that's what they had on this one.' "

Aviation Week says that "stealth helicopter technology in itself is not new and was applied extensively to the RAH-66 Comanche. Priorities are usually different versus fixed-wing aircraft. Reducing noise and making it less conspicuous is the first job (more main and tail blades reduce the classic whop-whop signature). Noise can also be reduced by aerodynamic modifications and flight control changes that make it possible to slow the rotor down, particularly in forward flight below maximum speed."

As for avoiding radar, Aviation Week writes that "radar cross-section reduction is also possible — you can't make a helo as radar-stealthy as a fixed-wing airplane, because of all its moving parts, but on the other hand it is generally operating at low altitude in ground clutter, and is not an easy target."

5 State of the Art Military Technologies That Helped Take Out Bin Laden

Custom stealth helicopters snuck through the darkness, bearing an elite group of tricked out of Navy SEALs with incredible high-tech weapons on the most important counterterrorism mission in U.S. history.And after almost a decade of hide and seek, the U.S. finally caught up to the world’s most wanted man -- Usama bin Laden.

Here are five cool technologies that very likely helped the elite members of Navy SEAL Team 6 get the job done.

Satellite-Linked Camera Feeds

Helmet-mounted cameras beamed live video from the front line back to American headquarters, enabling military and intelligence chiefs to closely monitor the operation, and giving them a first-person perspective from the safety of the Situation Room. President Obama and several key advisors witnessed real-time footage from the raid as he gave the order to SEAL Team 6 to move in.

Hyperspectral Image Processing

Sometimes human eyes just don’t cut it: Our eyeballs typically capture only a tiny portion of the light spectrum. "Hyperspectral" means outside of the spectrum, essentially capturing everything that the human eye cannot see. This kind of imaging technique is so precise, it’s able to separate things not based on appearance but a unique chemical fingerprint, and yes, you can also see in the dark. The National Journal reported that the Black Hawk helicopters that ferried Team 6 in were equipped with these cameras.

Stealth Drones

A key weapon in today’s modern terrorist warfare, stealth drones such as the Lockheed Martin RQ-170 Sentinel are fundamental to surveillance. Before the final attack, months were spent on pure reconnaissance; stealth drones, employing video cameras and hyperspectral sensors, streamline this process while staying undercover.

Stealth Black Hawk Helicopters

Photographs sold to Reuters revealed the remains of a top secret Black Hawk stealth helicopter sporting several modifications, a machine that allowed the U.S. team to infiltrate Pakistani undetected. Designed for special forces missions, these choppers can carry up to 11 soldiers and come with three types of guns: mini, chain, and gatling.

The tail design of the helicopter seen in these photos shows an unusual assembly, possibly hinting at a type of previously-unknown stealth capability, experts said.

"It was a secretly developed stealth helicopter, probably a highly modified version of an H-60 Blackhawk," reported Bill Sweetman on Aviation Week’s Ares blog. "The helicopter's tail features stealth-configured shapes on the boom and tip fairings, swept stabilizers and a "dishpan" cover over a non-standard five-or-six-blade tail rotor. It has a silver-loaded infra-red suppression finish similar to that seen on some V-22s."

Armored Hounds

Sometimes the most useful technology is actually man’s best friend. According to reports, a SEAL dog was imperative to the bin Laden raid. Almost always German Shepherds, these highly trained canines can sniff out dangerous explosive, provide valuable intel, and if necessary, even attack the enemy

'Stealth helicopters' used in Bin Laden raid

The US forces who raided the safehouse of Osama Bin Laden appear to have caught him completely by surprise - and to have avoided detection by Pakistani radar. How did they do it?

One answer, experts believe, is that the special operations team used previously unseen stealth helicopters.

Graphic showing modified Blackhawk

1. Silver finish makes it harder to detect on radar and by infrared sensors

2. Shape of tailboom has been altered and possibly enlarged to evade radar

3. Pan-like cover or hubcap over the rear rotor head conceals exposed machinery which is more easily picked up on radar

4. Extra blades on tail rotor reduce noise and lessen typical chopper sound

Rest of aircraft: There is speculation that the main rotor could also have had extra blades, retractable landing gear and a cover over the main rotor head

Source: Aviation Week

The evidence for this comes from images of the wreckage of one of the helicopters, which departing Seals destroyed after it crash landed in the compound.

The tail of the top secret aircraft survived, providing a treasure chest of clues for aviation experts.

After some detective work, these experts have concluded it was a UH-60 Blackhawk, heavily modified to make it quieter and less visible to radar.

They are confident the raid marks the first time that a stealth helicopter has been used operationally.

It wouldn't be the first of its kind in existence, however. Sikorsky Aircraft built a number of prototype stealth helicopters, known as the RAH-66 Comanche, for the US Army. The programme was cancelled in 2004, due to escalating costs, before the helicopter become operational.

RAH-66 ComancheThe RAH-66 Comanche had some stealth technologies

"What's new here is this was operational use," says Bill Sweetman, editor of Aviation Week. "We really haven't seen stealth helicopters used in this way before.

"The bottom line is about increasing the element of surprise. The less warning that the target has the better."

In this kind of situation an escape route for the aircraft might be needed, he adds, in which case time is of the essence.

To make a helicopter stealthy, you have to get rid of certain shapes and areas that are easily picked up on radar, says Tony Osborne, deputy editor of Rotorhub, a UK-based helicopter magazine.

Children in PakistanChildren collected parts of the wreckage

"You have to cover key parts so that the radar waves bounce in different directions or get absorbed...

"The tail rotor gearbox is covered. I've never seen that before in a helicopter. We know things are being played with all the time, but it is impressive to see it put into action."

The tail fin is completely smooth and appears coated in a pearlescent material that looks silver in some lights, and black in others, says Mr Osborne.

"I've only ever seen that on stealth aeroplanes, and it would probably absorb radar waves. Even the rivets are covered - radars are very sensitive and small rivets could give it away.

"The tail boom remains suggest the landing gear was retractable - again, usually it could be detected by radar, so retracting it would help avoid radar detection.

And don't forget the dogs...

  • Several reports say an unidentified canine was strapped to a human member of the Seals team as he was lowered into the compound
  • It was most likely needed to check for hidden explosives
  • New York Times says it was most likely a German Shepherd or Belgian Malinois, according to military sources

"It looks like the tail rotor has five or six blades. This would mean the rotor could have a slower rotation, which would mean less noise. Noise is caused by the blade tips spinning at high speed, hitting the air."

Slipping under the radar can also be possible without stealth technology. Most of Pakistan's radars are on the ground, and therefore angled in such a way that makes low-flying aircraft difficult to detect, Mr Osborne says.

A Pakistani intelligence official who wished to remain anonymous told the BBC's Syed Shoaib Hasan that the helicopters were not picked up on radar and were only detected whenseen entering the country from Afghanistan.

He said there were four helicopters, coming in very low.

There has been speculation that there was one more stealth helicopter, identical to the one that crashed, and that these were used as pathfinders, backed up by two larger Chinooks.

Map of Abbottabad