The an important problem for the Navy SEALs who slew Osama bin Laden was the crash of one of their helicopters.
It was no ordinary military chopper. Numerous aviation experts say they see several telltale signs of stealth technology in photos of what was left after the SEAL team tried to destroy the craft.
Some think it was a secret aircraft.
"Had this particular helicopter not crashed, we still would have not motif of its existence," said Gareth Jennings, the aviation desk redactor for Jane's Defence Weekly.
Jennings and other aviation experts say the helicopter may have been a heavily modified version of the UH-60 Black Hawk, a mainstay of the military's helicopter fleet.
But it may embody stealth technology adult for the now-canceled RAH-66 Comanche helicopter. That aircraft was designed to be an armed reconnaissance craft learned of carrying only two people.
Two of the aircraft were built for test flights before the Army repealed the procedure in 2004, not because of rendition but because it needed money to upgrade existing helicopters. At the period, Les Brownlee, then performing secretary of the Army, said, "We will maintain pertinent technologies amplified in the Comanche program."
At the same 2004 briefing about the cancellation of the Comanche, then-Army Chief of Staff Gen. Peter Schoomaker said, "much of what we've acquired out of Comanche we tin shove along into the tech pedestal for hereafter coupler rotorcraft kinds of capabilities as we see further out."
The helicopter in answer was left on the ground by the al Qaeda leader's compound during the raid early Monday.
The SEALs were able to destroy many of the main body of the helicopter when it became clear it couldn't fly. But the tail rotor assembly came down on the other side of the compound wall and was left largely intact deep inside Pakistan when the SEALs finished their task.
Pakistani crews were watched hauling the wreckage away on trucks covered with tarps. The Department of Defense, which would no annotate almost anybody presumption approximately a "stealth helicopter," also wouldn't mention if it's inquired Pakistan apt give the wreckage back to the United States.
"Given the very lusty barricade ties that Pakistan and China currently have, I wouldn't be surprised at all to see this wreckage bring an end to ... in Beijing," Jennings said.
"And that has to be of large concern to the U.S. Department of Defense, for with that technology, the Chinese alternatively any third celebration could both incorporate that technology into their own aircraft or they can figure out ways to defeat that technology, thereby disrupting stealth technology favor this largely needless in future actions," he said.
What makes the experts consider the aeroplane namely crashed in Abbottabad was a mystery "stealth helicopter?"
"The 1st entity that stood out, and it may seem like a small thing, is the color scheme. Whereas most Black Hawk Army helicopters are drew olive green, this particular one namely gray. Not just any gray; it's infrared-suppressant gray, and the intention of the IR gray, as it's understood, is to assist reduce the vulnerability of the helicopter to ground-launched heat-seeking missile systems," Jennings told CNN Pentagon Correspondent Chris Lawrence.
Photos from Abbottabad show that the chopper had a five-bladed tail rotor. "On a conventional Black Hawk, you have four blades. The counting of the more rotor blades on the tail rotor hub reduces the acoustic signature of the helicopter there by production it hard to hear, giving the SEALs that more few minutes to bring ... to an end the compound before anyone on the ground quite knows what's working on," according to Jennings.
Those 5 tail rotor blades are partially covered by a disk-like object that Jennings called a "hub-mounted vibration suppression system." He believes it provides extra noise suppression and some feasible conservation for the tail rotor from bullets of shrapnel. And it's not typical on military helicopters. "No, I've not seen that on an operational helicopter ahead," Jennings said. But he added that a similar system was part of the Comanche helicopter design.
The blades on that tail rotor also appear to be shorter and thinner than typical Black Hawk helicopter's blades. One former Army Black Hawk pilot, who asked not to be identified, said, "More blades and shorter blades manner the helicopter would make less noise in flight."
It's not equitable the tail rotor blades that are assorted. "On the main rotor convergence that was really broke at the SEAL group on the ground the blades themselves are threaded, which signify that these are carbon composite rotor blades as disapproved to accustomed metal rotor blades, which again signifies aspects of stealth technology that have been incorporated into this particular helicopter," Jennings said.
Some photos show chapters of the helicopter arise alike to non-secret stealth aircraft. "What's left of the tail partition of that helicopter, the shape of the fuselage, it's canted. It's angled. It's a fashion that's synonymous with fixed-wing stealth fighters such as the F-22, the F-35. Essentially, it's designed to defeat radar. If you eradicate right angles in an aircraft devise, radar waves can't skip back," Jennings said.
CNN'S Chris Lawrence contributed to this treatise.