Osama and Stealth Black Hawk 


Osama and Stealth Black Hawk

Highly-modified H-60s were employed during the US Special Forces operation that resulted in the death of Osama bin Laden on 1 May 2011. One such helicopter experienced mechanical trouble during the operation and the team was forced to destroy it before departing. The team members later departed in one of two MH-47 Chinooks with bin Laden’s remains. Two MH-47s were used for the mission to refuel the two MH-60s and as backups.

MH-60 Black Hawk stealth helicopter: One of two specially modified MH-60s used in the raid on Osama bin Laden‘s hideout in Pakistan on 1 May 2011 was damaged in a hard landing, and was subsequently destroyed by US forces. Subsequent reports state that the Blackhawk destroyed was a previously unconfirmed, but rumored, modification of the design with reduced noise signature and stealth technology. The modifications are said to add several hundred pounds to the base helicopter including edge alignment panels, special coatings and anti-radar treatments for the windshields.

In the 1 May 2011 operation that killed Osama bin Laden, it emerged that the 160th Special Operations Aviation Regiment, which operated the helicopters during the raid, used a heavily modified version of the UH-60. Features apparently include a modified tail section with extra blades on the tail rotor and other additions which significantly lower noise levels from that of conventional UH-60s. It also had low-observable technology similar to that of F-117 that enabled it to evade Pakistan Air Force radars. The aircraft seemed to include features like special high-tech materials, harsh angles, and flat surfaces, found only on sophisticated stealth jets. This came to light only when one of the helicopters used in the operation crashed and was subsequently destroyed except for its tail section.

Black Hawk is a four-bladed, twin-engine, medium-lift utility helicopter manufactured by Sikorsky Aircraft.

Role Utility helicopter
Manufacturer Sikorsky Aircraft Corporation
First flight 29 November 1974
Introduced 1979
Status Active service
Primary users United States Army
Republic of Korea Army
Colombian Armed Forces
Turkish Armed Forces
Produced 1974–present
Number built >2,600
Unit cost US$44 million (avg. cost fully equipped, 2008)[1]
Variants Sikorsky SH-60 Seahawk
Sikorsky HH-60 Pave Hawk
Sikorsky HH-60 Jayhawk
Sikorsky S-70

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

One of the helicopters had an issue – they’re not sure what as of now – and conducted a soft crash landing. The chopper hit the deck

U.S. forces quickly destroyed the Black Hawk, which was built by Sikorsky Aircraft, a unit of United Technologies Corp, to avoid any of its sensitive equipment falling into enemy hands

Two Black Hawk helicopters were supposed to hover over the bin Laden compound and allow Navy special operations forces to rappel to the ground.

When one of the helicopters ran into problems — including temperatures that were 17 degrees higher than expected — and had to land abruptly, two Boeing Co Chinook helicopters were called in to help get the U.S. troops out, said one U.S. government official, speaking on condition of anonymity.

One Chinook would have sufficed, but a second one was sent in case that helicopter also ran into trouble, said Pike.

One retired military helicopter pilot said the Black Hawk likely ran into an issue called “settling with power,” when high temperatures, a heavy load and high altitudes force an unplanned landing. “Those conditions just suck the RPM out of the rotor,” he said.

Sikorsky’s Black Hawks, which typically have a range of 360 miles, are considered reliable and have been real workhorses during the last decade of war, said one congressional aide.

The Black Hawk, which first began flying in 1978, has a crew of three or four and can carry 11 soldiers equipped for combat. It has a maximum gross weight of 22,000 pounds and can carry up to 9,000 pounds on an external cargo hook. It has a top speed of 187 miles per hour.

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.”

In addition, “in order to keep the radar cross-section down, you have to do something to treat the windshield,” he said. If a special coating was applied to the windshield it is “very plausible” that would make the helicopter more difficult to fly for pilots wearing night-vision goggles, he said.

That crash landing might have been caused by a phenomenon known as “settling with power,” which occurs when a helicopter descends too quickly because its rotors cannot get the lift required from the turbulent air of their own downwash. “It’s hard to settle with power in a Black Hawk, but then again, if they were using one of these [low-observable helicopters], working at max gross weight, it’s certainly plausible that they could have because they would have been flying so heavy,” the retired special operations aviator said, noting that low-observable modifications added “several hundred pounds” to the weight of the MH-60, which already weighs about 500 to 1000 pounds more than a regular UH-60 Black Hawk.

The special operations troops on the bin Laden mission destroyed the stricken aircraft — most likely using thermite grenades — but the resultant fire left the helicopter’s tail boom, tail rotor assembly and horizontal stabilizers intact in the compound’s courtyard.

Tail of the helicopter did not resemble any officially acknowledged U.S. military airframe.

Disc-shaped device that is seen covering the tail rotor in the photographs as a “hubcap

The early versions of the low-observable Black Hawks were not fitted with air-to-air refueling probes, the retired special operations aviator said. “The probe would disrupt the ability to reduce the radar cross-section,” he added. “There was no way to put some kind of a hub or cowling over the probe that would make it stealthy.” However, he said he did not know whether the models that flew the bin Laden mission had been equipped with such probes.

They were likely carried to the target in two UH-60 helicopters, which can carry various weapons, more than 10 troops, plus high-tech gear to help the aircraft fly at night. White House officials did say only two helicopters were involved, but additional aircraft likely accompanied them to guard the commandos from counterattacks by jihadis or Pakistani aircraft, or to rescue any troops that might be stranded.

Several years ago, interrogators had persuaded detainees to reveal an individual who worked as a trusted courier for bin Laden. After several years, officials gradually learned more about the courier, and identified his residence in August 2010, in the town of Abbottabad.

It appears to be a significantly modified version of a Sikorsky H-60 Black Hawk, although whether an MH-60K, L or M version is still unknown. The U.S. Army’s 160th Special Operations Aviation Regiment (Airborne), the Night Stalkers, uses all three types of MH-60s.

Stealth enhancements for rotorcraft are not new and were applied extensively to the Boeing/Sikorsky RAH-66 Comanche, canceled in 2004. Compared with fixed-wing stealth, more emphasis is usually placed on noise and IR signatures.

Noise can be reduced and made less conspicuous by adding blades to the main and tail rotors. It can also be reduced by aerodynamic modifications and flight control changes that make it possible to reduce rotor rpm, particularly in forward flight below maximum speed. Under any such effort, a reduction in IR would be critical; the Comanche had an elaborate system of exhaust ducts and fresh-air ejectors in its tail boom.

Classic radar cross-section (RCS) reduction measures include flattened and canted body sides, making landing gear and other features retractable, and adding fairings over the rotor hubs. But it is believed that a helicopter cannot yet be made as radar-stealthy as a fixed-wing airplane, as helicopters generally operate at low altitude and against ground clutter. Still, reducing RCS makes jamming more effective, whether from the helicopter itself or from a standoff jammer.

According to Pentagon budget data from fiscal 2010, there have been plans for an MH-60M version. Following standard practice, this would have been the most recent Black Hawk variant for the Army to be upgraded for U.S. Special Operations Command (Socom) standards.

The aircraft was damaged during the mission and abandoned. The mission team destroyed most of the airframe but its tail section landed outside the wall of the target compound and escaped demolition.

Stealth helicopter technology is not new and was applied extensively to the Boeing/Sikorsky RAH-66 Comanche, cancelled in 2004. Compared with fixed-wing stealth, more emphasis is usually placed on noise and infrared signatures.

Noise can be reduced and made less conspicuous by adding blades to the main and tail rotors. It can also be reduced by aerodynamic modifications and flight control changes that make it possible to reduce rotor rpm, particularly in forward flight below maximum speed. Infrared reduction measures are crucial – the Comanche had an elaborate system of exhaust ducts and fresh-air ejectors in its tailboom.

Radar cross-section (RCS) reduction measures include flattened and canted body sides, making landing gear and other features retractable, and adding fairings over the rotor hubs. It usually is not possible to achieve the same – you can’t make a helo as radar-stealthy as a fixed-wing airplane, but helicopters generally operate at low altitude in ground clutter. Reducing RCS also makes jamming more effective, whether from the aircraft itself or from a standoff jammer.

Sikorsky Aircraft Delivers 100th New Production UH-60M BLACK HAWK Helicopter to U.S. Army.  With a new airframe, avionics and propulsion system, the UH-60M helicopter is the latest and most modern in a series of BLACK HAWK variants that Sikorsky has been delivering to the Army without interruption since 1978.

“The UH-60M helicopter delivers great technology and a load of confidencebased on Sikorsky’s three decades of experience in designing, building and servicing the workhorse of the United States Army,” said Sikorsky President Jeffrey P. Pino, a retired U.S. Army Master Aviator with 26 years of combined active, reserve and National Guard service. “I can talk about the aircraft’s reduced pilot workload, increased lift, better protection and enhanced survivability, but nothing means more than when soldiers tell us how much they depend on and trust this helicopter.”

Col. L. Neil Thurgood, Utility Helicopters Project Manager for the U.S. Army, noted an entire battalion of the aircraft has deployed to Afghanistan. “The UH-60M BLACK HAWK has been warmly received by our soldiers who appreciate its performance, durability and robust design,” said Col. Thurgood, who spent time with employees in the Stratford plant, thanking them for the important part they play in America’s defense.

The Army currently has more than 1,740 BLACK HAWK variants with more than 5.8 million combined flight hours in inventory, constituting the world’s largest

and most battle-tested BLACK HAWK fleet. The Army BLACK HAWK fleet will soon exceed more than 1 million hours of combat duty in the Iraq and Afghanistan war theaters since 2003.

“The BLACK HAWK is a great aircraft, the military’s battlefield transport of choice,” Pino said. “With the UH-60M helicopter, the Army and Sikorsky are building upon that tradition and ensuring that it will continue for generations to come.”

The UH-60M helicopter’s new composite spar wide-chord blade will provide 227 kg (500 lbs) more lift than the current UH-60L blade. The new General Electric T700-GE-701D engine will add more horsepower and allow additional lift during external lift (sling load) operations.

The UH-60M helicopter represents the Army’s third standard baseline BLACK HAWK version in the 30-year production history of the program. Sikorsky delivered the UH-60A BLACK HAWK helicopters from 1978 until 1989, and delivered the UH-60L from 1989 until 2008. Not content with the status quo, Sikorsky is even now working on an upgrade to the UH-60M helicopter.  The upgrade will feature

Fly-by-wire flight controls, full authority digital engine controllers, enhanced cockpit displays and a composite tail-cone.  Brig. General Walter Davis, Director of Army Aviation, received a briefing on this effort.

Sikorsky Aircraft Corp., based in Stratford, Conn., is a world leader in helicopter design, manufacture and service.  Its mission statement reflects the company’s long commitment to safety and innovation: “We pioneer flight solutions that bring people home everywhere… every time(TM).”  More information is available at the interactive http://www.sikorsky.com Web site.

United Technologies Corp., based in Hartford, Conn., provides a broad range of high technology products and support services to the aerospace and building systems industries.