Bin Laden Mission: More Wild Helicopter Tales

Curiosity unsatisfied is like the itch that can’t be scratched, which is how I feel in sorting through reports on the spec ops helicopter crash during the May 2011 raid that took out Osama bin Laden. I wrote about it in this blog a few months ago.I keep seeing accounts of this event and although they agree on one basic fact-a helicopter definitely crashed-they certainly don’t agree on why or what exactly happened. I’ve read three books on the topic: Mark Owen’s controversial No Easy Day: The Autobiography of a Navy SEAL, Man Hunt by Peter Bergen and SEAL Target Geronimo by Chuck Pfarrer. Owen was a member of SEAL Team Six, the unit that carried out the raid, and was actually aboard the helicopter when it crashed. Pfarrer is a former member of SEAL Team Six and is now an author and screenwriter. He had no involvement with the operation.In his book and a subsequent television interview with 60 Minutes, Owen said the original tactical plan was to “fly to the X” and fast rope assaulters to both the top of the bin Laden house and the compound ground floor simultaneously. He was in the ground insertion team, but as the helicopter approached hover and the team prepared to rope down, the aircraft became unstable, seemed to lose yaw control and touched down hard in the middle of the walled compound with everyone still aboard. It came to rest with its tail boom propped up on the wall and the tail rotor just outside the wall’s perimeter.No one was injured, so the SEALS disembarked, adjusted and carried on with the mission. But they made one change on the fly. After the crash, the second helo that was supposed to insert a team on the roof diverted and roped the team down from the outside of the compound or landed. It’s not clear which. They then gained access through the compound’s high walls with breaching charges, according to Owen’s account.Did the Black Hawk suffer a tail strike on the wall or some other damage, thus precipitating the crash? Bergen, who may have used sources close to Owen-or certainly sources different than Pfarrer’s–seems to think that, as some have speculated, the helo got into vortex ring state-settling with power-and simply lost vertical control. “The biggest problem was not correctly matching the wall that surrounded the compound in the life-size mock-ups they had used for rehearsals,” Bergen writes. “The solid walls of the actual compound had caused turbulent aerodynamics for the first Black Hawk when it hovered to drop the SEALS into the courtyard and had necessitated the hard landing.” This squares with Owen’s account generally, if not in detail.But in his book, Pfarrer is having none of this. He claims to have talked directly to sources involved in the raid who told him the team did insert from the roof, as planned, and found and killed bin Laden within 90 seconds of insertion, not after a 15-minute assault from the ground floor, as Owen claims. Pfarrer says the roof team assaulted down through the building and took out other targets. Pfarrer also claims the crash occurred as the Black Hawk, which eventually landed on the roof, was repositioning to outside the wall to stage for the exfiltration. The aircraft lost control and crashed tail first into the courtyard, according his account. And it had nothing to do with settling with power, but a freak mechanical failure of dual electronic control systems that Pfarrer calls “green units.”From Army nomenclature I’ve found on the Black Hawk, I surmise that the U/MH-60 does have a dual channel flight control system-it’s actually a stability augmentation system-that provides short term damping in all three flight axes. But because the two systems max out at 10 percent control authority, it’s not clear to me if a dual failure would result in aircraft loss. Then again, the aircraft involved clearly were not plain-vanilla Black Hawks, having been tricked out with acoustic damping rotors and radar suppression features, not to mention other secret stuff we’ve never heard about. Pfarrer called them Stealth Hawks and claims that two even more super-secret helos called Ghost Hawks were in theatre but were kept on the ground when it was decided that providing fighter top cover for them would risk drawing too much attention from Pakistani radar and the Army simply wasn’t willing to risk exposing the technology by losing it. It’s possible that these aircraft are based loosely on the U/MH-60, but are in fact custom one-offs made just for such sensitive tactical work. It’s just as possible that they don’t exist, I suppose.Why the difference in accounts? Pfarrer claims administration officials watched the operation in real time through an RQ-170 Sentinel drone link and knew the crash occurred on the exfil, not the insertion. So why did they-and Owen-hew to the story that the helicopter crashed on insertion? Pfarrer supports his claims with what he says are eyewitness accounts from Pakistani neighbors, corroborated by a Pakistani military report that claimed clear evidence of the assault having been carried out from the top down. In explaining how the widely photographed almost intact tail rotor section came to rest against an outer wall, Pfarrer said it was blown out of the compound when the SEALS blew up the crashed helicopter. I’m not sure I buy that. In this photo, that pipe looking thing snaking over the wall is the rotor driveshaft. Seems hard to believe it would repose like that if it had arced over the wall. Pfarrer doesn’t offer a motive for these disparate accounts, merely claims that his version of the event doesn’t match either Owen’s or the Pentagon’s. Not that it matters much, other than being a curiosity, but one should never mistake any of this for an NTSB finding of cause.Indeed, some of Pfarrer’s aviation reporting struck me as a little suspect. He described the RQ-170 departure from Jalamabad thusly: “The delta-shaped object lumbered down the runway…and lifted off on a pair of afterburners framed by titanium thrust vectors.” He described the Sentinel as climbing vertically and capable of supersonic flight. The RQ-170 is a dark project, but what reporting has surfaced on it suggests that it’s a single-engine aircraft, which is in keeping with drone design of that size and type. It’s believed to have a GE TF34 turbofan engine, with about 9200 pounds of thrust. Two engines in that range would give a 10,000 pound drone a two-to-one thrust- to-weight ratio, far greater than any modern fighter, including the F-22.The RQ-170, by the way, is the type that the Iranians claimed to have captured; it looks like a mini B-2 bomber. Drones have been mostly about stealth and endurance, not speed or the maneuverability provided by thrust vectoring. Mach +1 and stealthy drone would seem to go together like oil and water and afterburners wouldn’t be on the short list of low observables. But then not many of us know much about what goes on in the dark programs. The fact that Pfarrer is also a screenwriter gives me certain pause, too, since screenwriting and truth aren’t exactly joined at the hip. While we’re on that subject, later this week, a feature film about the bin Laden operation by Kathryn Bigelow called Zero Dark Thirty will go into limited release. It’s likely that it will use the crash-on-insertion scenario, whether true or not.So, having read all this material, I have no better sense of what really happened to the helo than when I started. Even in my wildest conspiratorial speculations, I can’t construct a plausible reason why the Pentagon would misstate the real reason for the crash. Maybe there is no explanation, not for the crash, but for sticking with a story that isn’t true.If you gain a certain grim entertainment from reading accounts of the same event that are profoundly different, these books are worth the effort. One thing all three of them do with not a hint of inconsistency is to describe, in at least general terms, the staggering capability these special operations teams-and related intel agencies–have developed during the past decade, not the least of which is super-secret helicopters that sound like distant waterfalls in the night.