Experts Describe the Secret, Stealthy Chopper From the bin Laden Mission

By Valerie Ross | May 9, 2011 5:07 pm

What’s the News: The helicopter that crashed during the raid on Osama bin Laden’s compound earlier this week was a stealth design that the US government had kept secret, according to aviation experts. The military is still keeping mum and the SEALs—keeping with protocol—burned the aircraft after it went down. But information gleaned from photos of the surviving tailboom (the part that holds the rear rotor) and clues from other stealth aircraft suggest the helicopter was an H-60 Blackhawk, heavily modified to escape radar detection and fly more quietly—explaining why Pakistani air forces didn’t detect the helicopters.

How the Heck: To the experts’ eyes, several unusual features marked the helicopter as a never-before-discussed stealth model.

  • Rotor: The rotor had five or six blades—rather than the usual four—that were topped with a shield-like cover, which would keep down turbulence, making the helicopter more efficient, and reduce noise.
  • Skin: Most helicopters are liberally studded with rivets, but this one’s skin was unusually smooth and nearly rivet-free, a sign that this was a departure from the normal design.
  • Outer Shell: What’s more, the helicopter’s boom and tip-farings were reshaped from the original Blackhawk design to scatter radar beams rather than reflect them right back.
  • Paint Job: Coating the copter might have been an infrared suppression finish, which would camouflage the aircraft’s infrared signature and has been used on F-22′s and other stealth planes.

What’s the Context:

  • No one knows exactly how these helicopters came to be, since the government hasn’t released any info, but some of the stealth features may have come from the RAH-66 Comanche, a stealth helicopter program that didn’t make it past the prototype stage before it was canceled in 2004, or from another stealth-chopper development program called MH-X.
  • Since most of the plane was burned, it’s impossible to tell from the photos just what the whole thing looked like. Making their best guess, a journalist/ex-pilot, teamed with a graphic artist, did a mock-up, above, comparing the regular Blackhawk to a likely stealth design.

Image: David Cenciotti and Ugo Crisponi

CATEGORIZED UNDER: Technology
  • Iowa

    Sweet. From what I learned reading various news articles, it sounded like they slapped some stealth on the helecopter. Nice to know that was a stupid explanation. I guess the hundreds of billions we give to the military actually goes to some kick ass, useful technology! Makes me respect the Federal Budget a bit more… only a bit though.

  • http://discovermagazine.com Iain

    That whirling rotor must have a huge radar signature, and that’s going to limit your stealthiness. Maybe the Pakistani’s were asleep, or watching a cricket match.

  • Gazza

    Nothing can mask the noise of rotors, regardless of what these “experts” may claim. The noise would have woke up everybody in a 100m radius, and we are expected to belive that OBL was surprised in his bedclothes and didn’t have time to get a weapon? What utter rubbish, an insult to the readers intelligence.

  • Glidingpig

    Huntington Beach in Orange county CA has a ‘stealthy’ police helicopter. You would be surprised at how quite it is when it’s coming at you. It is much louder when it is going away. I suspect this one would be the same.

  • matt sculley

    the rotors are coated in special paint to diminish the radar signature, your conclusions are still sound Iain… Gazza, Pakistan is filled with rolling valleys and mountains, which easily bounce sound waves up into space… so to claim that everyone would of heard the choppers for a 100m radius is absurd and unfounded….it also reflects on your intelligence.

  • GuruOfChem

    A big portion of the noise comes from interaction between the wash from the tail rotor and the main rotor. Previous noise suppressive designs have either shrouded the tail rotor or used ducted air in place of the tail rotor to keep the chopper from rotating uncontrollably. Glidingpig is also correct – most choppers are much louder from behind, so as long as you are flying at your target, there can be very little discernible noise. As far as a radar signature goes, helicopters tend to be pretty visible, but reducing the signature as discussed (paint, carbon skin, etc.) would help, and helicopters flying low are hard to spot on radar to begin with.

  • Rogue

    I don’t know much about choppers, so forgive any ignorance my questions may bely. There does not appear to be a refueling probe on the stealth chopper: is that because it could be retracted and enshrouded by the aircraft’s skin, or is it omitted in the interests of stealth? Is there a stealthier non-probe method of aerial refueling for helicopters or has that capability been omitted to permit a cleaner design? Would increased stealth trump range and justify the removal of in- flight refueling capacity? Do the open doorways affect the choppers radar and noise signatures?Finally, is there anything to suggest that the helicopter didn’t malfunction and crash but was rendered inoperable due to battle damage? Thanks for any enlightening responses.

  • dave chamberlin

    Some conspiracy quacks are pointing to the small percentage chance of a black hawk helicopter crash during such an operation. But if it was a experimental helicopter that the pilot wasn’t completely trained on then the chances of a crash go way up. I understand stealthy aircraft sacrifice stability for stealthiness as well so while our government says the crash was because of a miscalculation in ground temperature meaning the craft needed more lift than expected, it may have just been the stealthiness of the helicopter made it a lot harder to fly.

  • disposablechild

    Its kind of pitiful that such an awesome, well equipped, and highly expensive helicopter crashed on such an important mission. Not much stealth when you smash into a building.

  • Mike

    The helicopter was damaged inside the high walled compound after a “hard” landing. Landing a helicopter in a high walled enclosure like the compound is dangerous. The walls provide a natural obstruction to the down force needed to keep the copter up. The walls act to deflect the air up and back into the rotors. This creates a convection type air current that returns the air pushed out the bottom of the rotors back up and around into the top of the rotors again. This would greatly reduce the air pressure beneath the copter needed to keep it up. No more lift. The helicopter could have fallen like a stone if it was too close to the wall or just in the wrong spot.

  • Abulabad

    Secret military assassin squad that do not official exist, listen up.
    Your objectives:
    1. Destroy and dispose of the target enemy person.
    2. OK good, now cover your tracks and Destroy the helicopter!

    Good job. Mission Complete… Now inform public on Nation TV of operation success!

    Do Americans not suspect this is odd for secret mission to make such media noise? It is ironic at the least but what I know anyway, haha!

  • Popsiq

    It certainly would have wakened the neighborhood when the rotors hit the wall. The subsequent ‘hard landing’ wouldn’t have been very quiet, either (How did the tail section get over a wall, upside down, if the AC was burned?). One can only think the demolition occurred after the assault on Bin Laden’s house.

    All that aside, the two supporting Chinooks would have made about the same sound as a flying diesel locomotive, with the added rotor noise thrown in to disturb sleeping dogs.

    A stealth operation this was not.

  • Rayce

    In reply to matt sculley’s post. Why is it that civilians in Islamabad heard the helicopters from their house and tweet about it before pakistan was informed about the mission? Your assumptions also reflects on your intelligence.

  • shiraz

    I have military choppers training about 3 km from my house. They are boldly noisy.
    even my deaf neighbour complains about them.

  • http://paragonit.net/ BusinessIT services

    Good post by auther on experts describe the secret stealthy chopper from the obl mission

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