Assault on Bin Laden: mystery of the downed chopper

I think we're going to be left to our own devices in deducing just what sort of a helo got stuck on OBL's service yard; at least I've seen no-one from the armed forces, CIA or the White House willing to discuss anything about it. Not that anyone's asked them either? Some people here have (what to me appear superhuman) skills of going through impenetrable seeming documents and sources from airspace restrictions to federal budget footnotes and come up with reasonable assumptions. I'm in awe.

From a design standpoint a helicopter doesn't seem like a prime candidate for stealth, even with the RAH-66s of this World ... I've bookmarked a couple of links to bespoke rotor flow softwares which seemed exclusively flow dynamics related. It's been a couple of years since I've visited them, but both were billed "state of the art" at the time and even now - it seems to me - it'd be a bit of a stretch to make them "multiphysics enough" to include both acoustics and RCS and coalesce all the design goals into a perfectly integrated product. Dunno, perhaps finite element methods have leaped forward in the mean time and this sort of thing is within the reach of any wet behind the ears mech BEng these days. I do vaguely remember a German Prof. Whatshisname working on reducing noise by adding small, actuated control surfaces to the main rotor - but that was for Eurocopter, I think. Me, I was just slightly surprised to see the tail rotor "stealthized", I would've thought NOTAR an obvious choice for such an "application". But then again I don't design helicopters.

About the raid being handled "extremely poorly" vis-a-vis a ficticious Pakistan nukes-grab and general political expediency ... I think our "allies" have clearly stated that the US will not be privy to their weapons' location; the existence of any agreement to "secure" the stockpiles in case of a radical uprising has been debunked. US intel dropped the ball way back with AQ Khan already (even instructing European spooks to stand down, I think), directly resulting in the worst rogue nukes profileration in memory - at the bare minimum Libya, North Korea and Iran got their goods (or "bads") from them. The idea of DevGru or even a battalion of Rambos solving this by the way of stealthy insertion ... is fanciful. On top of the manifest tenuousness of trust, it's the old guard, the Musharraf generation that was at least willing to play give-us-military-aid-and-we'll-behave-ball; worryingly there's increasing radicalization in the younger ranks coming up. And to add to the reality check - Pakistan ranks as the 6th most populous country in the World; by mid-century there'll be more folks there than there are in the US now. Can you imagine, say, the Chinese sending a commando force to "forcibly disarm" the US, or the UK?

By the way of "operational quietness" this option was the most stealthy put on the table by those who actually have to execute such things; having a couple of B-2s drop a precision payload on the compound would've also been linked to the US fairly instantly, I think. That the Pakistanis had to be excluded from the planning (as per McRaven's doctrine and previous "relations empiricism" i.e. high value targets getting tipped off) obviously necessitated accepting a level of exposure after the fact. As to the element of surprise, I think Al Qaeda - after at least a decade of relentless pursuit - has had more than a fair warning by now. We play the hands we are dealt and right now OBL's catch-me-if-you-can "mystique" is coming back to bite him and his pet projects. Besides, in a couple of predominantly islamic countries there have already been revolutions based on ... "On Strategic Nonviolent Conflict" (Robert L. Helvey, AEI) and social media tools specially engineered by human rights activists.

Not a resounding success for OBL and his band of blowhard acolytes, for I doubt said "Arab Spring" revolutionaries' ideal is to have an omnipotent medieval caliph replace their decrepit and/or dynastic strongman. Especially as we have competing examples of such religiously driven systems on full display in Iran and Saudi Arabia.
 
UpForce said:
From a design standpoint a helicopter doesn't seem like a prime candidate for stealth, even with the RAH-66s of this World ... I've bookmarked a couple of links to bespoke rotor flow softwares which seemed exclusively flow dynamics related. It's been a couple of years since I've visited them, but both were billed "state of the art" at the time and even now - it seems to me - it'd be a bit of a stretch to make them "multiphysics enough" to include both acoustics and RCS and coalesce all the design goals into a perfectly integrated product. Dunno, perhaps finite element methods have leaped forward in the mean time and this sort of thing is within the reach of any wet behind the ears mech BEng these days.

Both finite element methods and methods of moments have, in the last 5 years, become much more accessible. For example, I have regularly been using CUDA (http://www.nvidia.com/object/cuda_home_new.html) and OpenCL (http://www.khronos.org/opencl/) based finite element simulations to compute the RCS of objects derived from photographs using OpenCV (http://opencv.willowgarage.com/wiki/) and OpenFrameworks (http://www.openframeworks.cc/). This is where my analysis of the J-20 came from, and I had been planning to do an article on how it was done.
Hedge is one package that can use GPU computing for computational electromagnetics:
http://mathema.tician.de/software/hedge
There are a number of GPU shaders and CUDA kernels for finite element methods as well. Simple optical methods are sufficient for modeling some scenarios, however, and require much less power.

In industry, there have been significant advances in modeling and simulation capabilities specifically for the survivability of rotorcraft. A group at Sikorsky apparently made some headway with this several years ago, unfortunately I have not yet found a source for this that I can post.

Now that the story is out of the mainstream news cycle...

We'll be generous and assume a standard, unmodified UH-60, as any of the modifications discussed would likely have a negative impact on performance. According to most accounts, there were 24 assaulters on the two primary aircraft (our UH-60s), which would mean the aircraft were about fully loaded. A fully loaded UH-60 has a nominal range of 360 or so miles. DoD reports that the assault staged out of JBad, though local observers originally reported Ghazi AB in Pakistan (where the US has a presence, originally for flood relief operations).

Even with the most direct route to the target from JBad, 160 miles each way, a standard UH-60 would have no time on target (planned for 30 minutes), and little reserve. This is ignoring terrain, air density, and a whole lot of other factors that would come into play and increase fuel consumption. Most routes from JBad would also expose the assault force to multiple AAA sites and radars, such as those at Peshawar and Cherat. Routes that avoid AAA sites would add significant distance, and require more fuel. Sean O'Connor's list of worldwide SAM sites (http://geimint.blogspot.com/2008/06/worldwide-sam-site-overview.html) is a good starting point if you are curious about this.

If the assault force had staged out of Ghazi at Tarbela Air Field, the range to the target would have been significantly less, about 80 miles round trip. Using Ghazi would also have decreased exposure to air defense sites, and provided different opportunities for using terrain to mask an approach to the target. Regardless, it's still unlikely that the assault force recovered to Ghazi, though it could have been used to refuel on the way out (though that too is unlikely). They still would have been getting out of Pakistan as fast as possible. The activity observed at Ghazi by locals could have easily been CSAR support, which was provided by USAF and would have appeared to be an assault force to the casual observer.

Given all that, it seems very likely that the assault force refueled at some point, most probably inside Pakistan. Air refueling would be unlikely for a number of reasons. Either they stopped at Ghazi both ways, or there was a FARP inside Pakistan. This could have been done using fuel bladders on the two MH-47s if the assault blocking force was used to provide security, or other assets were used exclusively for the FARP. In the past TF160 has done it both ways.

It's reasonable to assume that modifications to a UH-60 would decrease performance and range. Even a small decrease in range would alter the mission planning significantly and require a FARP, or mulitple FARPs, within non permissive territory. A FARP decreases some risks (running out of gas), but increases others (chances of discovery, contact, accidents).

However, I like turtles.
 
Orionblamblam said:
Catalytic said:
In the unlikely event of having to snatch Pakistan's nukes within the next few years, presumably the US would like to appear to have a second trick up their sleeve.

No longer. The OBL raid was handled EXTREMELY poorly by the administration, for any purpose beyond Obama-promotion. The purpose of Special Forces raids are not for PR, but to get a job done quietly. The proper response by the administration should have been... utter silence. Express mild surprise if the raid is ever brought up in a press conference. Let rumors that the US had taken out OBL fly, and *eventually* confirm that OBL was no longer a concern. This way, nothing is confirmed. The raid on the compound is left a mystery. Other Al Queda targets that could/would/should be targetted afterwards would not get nearly the same level of warning.

And Pakistans military would not get the same major wakeup call that they need to upgrade their air defenses against rapid stealthy incursions.

By going so blatantly public with this, Obama has made future military missions that much harder or even potentially impossible, while tacking on needless diplomatic problems.

So... good job.
Very good post OBB in fact why not bring the body back to A-stan and place it on a goat path next to a cave complex. Then all the sources and methods could have been kept secret and we could still have presented the proof OBL was dead.
 
quellish said:
Given all that, it seems very likely that the assault force refueled at some point, most probably inside Pakistan. Air refueling would be unlikely for a number of reasons. Either they stopped at Ghazi both ways, or there was a FARP inside Pakistan. This could have been done using fuel bladders on the two MH-47s if the assault blocking force was used to provide security, or other assets were used exclusively for the FARP. In the past TF160 has done it both ways.

It's reasonable to assume that modifications to a UH-60 would decrease performance and range. Even a small decrease in range would alter the mission planning significantly and require a FARP, or mulitple FARPs, within non permissive territory. A FARP decreases some risks (running out of gas), but increases others (chances of discovery, contact, accidents).

Highly probable that there was a "Fat Cow" (CH-47 FARP) in the effort. Given the pit crew training of the SOAR ground personnel and the overhead imagery, it was probably not as hard as one might think to find a quiet valley or bluff in the mountains and quickly refuel to hawks. Also recall that the 47's were their rapidly for the exfil. They were likely holding "one ridgeline back" from the target area.
 
bobbymike said:
why not bring the body back to A-stan and place it on a goat path next to a cave complex. Then all the sources and methods could have been kept secret and we could still have presented the proof OBL was dead.

There were certainly better ways to handle this. Psyops experts could have dreamed up some interesting and effective ways to use bin Laden, dead or alive. "Shot dead by Americans," he's a martyr, plain and simple. "Shot dead by his gay lover over a spat regarding OBL's dalliance with a gay Mossad agent" would certainly have done some interesting things to his public aura.

If he were to simply vanish with all his data, and anyone at the compound who had any idea what really happened were to also disappear or suddenly find themselves slightly dead, then bin Laden could potentially have continued to issue orders, at least for a while. Orders dreamed up by, say, the CIA.

"Bin Laden has defected to the US and converted to Christianity/Judaism/Wicca" would have played hash with his image as well.

A tad out of scope for this particular thread, I imagine.
 
yasotay said:
Highly probable that there was a "Fat Cow" (CH-47 FARP) in the effort. Given the pit crew training of the SOAR ground personnel and the overhead imagery, it was probably not as hard as one might think to find a quiet valley or bluff in the mountains and quickly refuel to hawks. Also recall that the 47's were their rapidly for the exfil. They were likely holding "one ridgeline back" from the target area.

The problem there though is that if you have a MH-47 FARP, you don't have room to carry a full security element on that transport. Since you don't go with a single FARP helo, that would mean that both MH-47s carried the FARP gear and fuel in, so where was the security team and support teams (tactical SIGINT, collection team, 'navigators', etc)? So if they FARP'd, they would have needed more assets than have been mentioned before, and they almost certainly did FARP.

A casual human survey of the terrain across several possible infil routes didn't turn up a "good" FARP location, and an automated tool only turned up 2 (which were not that great. one was very close to a military facility). I'm sure they are out there. You have to wonder if the FARPs were observed by ground teams for weeks beforehand, and if so, when the ground teams were extracted and how.
 
Not much of a surprise now that Islamabad is making noises about letting the Chinese have a look at what's left. Considering how many pieces were taken as souvenirs by early gawkers I wouldn't be surprised if they already had a sample of RAM from it.
 
UpForce said:
I think we're going to be left to our own devices in deducing just what sort of a helo got stuck on OBL's service yard; at least I've seen no-one from the armed forces, CIA or the White House willing to discuss anything about it. Not that anyone's asked them either?

http://www.dodbuzz.com/2011/05/09/dod-what-secret-helicopter/
 
quellish said:
yasotay said:
Highly probable that there was a "Fat Cow" (CH-47 FARP) in the effort. Given the pit crew training of the SOAR ground personnel and the overhead imagery, it was probably not as hard as one might think to find a quiet valley or bluff in the mountains and quickly refuel to hawks. Also recall that the 47's were their rapidly for the exfil. They were likely holding "one ridgeline back" from the target area.

The problem there though is that if you have a MH-47 FARP, you don't have room to carry a full security element on that transport. Since you don't go with a single FARP helo, that would mean that both MH-47s carried the FARP gear and fuel in, so where was the security team and support teams (tactical SIGINT, collection team, 'navigators', etc)? So if they FARP'd, they would have needed more assets than have been mentioned before, and they almost certainly did FARP.

A casual human survey of the terrain across several possible infil routes didn't turn up a "good" FARP location, and an automated tool only turned up 2 (which were not that great. one was very close to a military facility). I'm sure they are out there. You have to wonder if the FARPs were observed by ground teams for weeks beforehand, and if so, when the ground teams were extracted and how.

Actually we really don't know how many "other" aircraft were involved in the effort. It is possible there were other SOAR assets involved. The Fat Cow does not have to be on the ground for much more than thirty minutes (assuming the aircraft need a full fuel load). One MH can carry enough fuel for top off of two Hawks and security could be on the other. Also with the extended fuel sponsons the MH-47 have lots of gas on their own without the internal tanks. Although I suspect you are right that the FARP location was probably under observation for some time by assets, with several alternates planned for. You really don't need more than a football field sized location to put in a Fat Cow FARP for a small two ship Hawk element.
 
yasotay said:
Actually we really don't know how many "other" aircraft were involved in the effort. It is possible there were other SOAR assets involved. The Fat Cow does not have to be on the ground for much more than thirty minutes (assuming the aircraft need a full fuel load). One MH can carry enough fuel for top off of two Hawks and security could be on the other. Also with the extended fuel sponsons the MH-47 have lots of gas on their own without the internal tanks. Although I suspect you are right that the FARP location was probably under observation for some time by assets, with several alternates planned for. You really don't need more than a football field sized location to put in a Fat Cow FARP for a small two ship Hawk element.

Right. You wouldn't have just one MH-47 FARP, losing one would abort the assault. If you have two, there is no room for the 40-60 men for the blocking force, etc. Open reporting indicates 2 MH-47 and 2 "blackhawks" at the target. It's certainly possible that additional MH-47s were used to set up FARPs.

So either there were many more assets involved - which makes the operation MUCH more complicated, detectable, and prone to error - or our "blackhawks" had much longer legs and didn't FARP (or FARP'd less, or used Ghazi).

But that would make it much less likely that it was a "modified blackhawk". ESSS wings with tanks could increase the range, but have other performance drawbacks, and may cut into useful load. They would also destroy the signature, and not allow for a fastrope insertion (the MH-60K has different sponsoons for carrying fuel, which may allow fastroping).
 
quellish said:
yasotay said:
Actually we really don't know how many "other" aircraft were involved in the effort. It is possible there were other SOAR assets involved. The Fat Cow does not have to be on the ground for much more than thirty minutes (assuming the aircraft need a full fuel load). One MH can carry enough fuel for top off of two Hawks and security could be on the other. Also with the extended fuel sponsons the MH-47 have lots of gas on their own without the internal tanks. Although I suspect you are right that the FARP location was probably under observation for some time by assets, with several alternates planned for. You really don't need more than a football field sized location to put in a Fat Cow FARP for a small two ship Hawk element.

Right. You wouldn't have just one MH-47 FARP, losing one would abort the assault. If you have two, there is no room for the 40-60 men for the blocking force, etc. Open reporting indicates 2 MH-47 and 2 "blackhawks" at the target. It's certainly possible that additional MH-47s were used to set up FARPs.

So either there were many more assets involved - which makes the operation MUCH more complicated, detectable, and prone to error - or our "blackhawks" had much longer legs and didn't FARP (or FARP'd less, or used Ghazi).

But that would make it much less likely that it was a "modified blackhawk". ESSS wings with tanks could increase the range, but have other performance drawbacks, and may cut into useful load. They would also destroy the signature, and not allow for a fastrope insertion (the MH-60K has different sponsoons for carrying fuel, which may allow fastroping).
Lets not forget that the SOAR put the Robinson Tank Company in business with the internal "Robby" tanks that are special designed for the MH-60 series. So it is possible that the "Stealthhawk had to fuel for the mission from the start, or at least to make it to the objective and then FARP on the exfil. Would add to the weight of course, but then there is no telling if the aircraft had tweaked engines. If you are going to spend the money on a stealth helo then maybe the engines get the treatment too.

Fun conjecture
 
What's the significance of a generic fuel cap? Other than whatever this one went on held 181 USG in that tank?


blackstar said:
Saw this on the NY Times site. Don't think it has been posted here yet.
 
In an article in Aviation Week this week, a source of theirs claims that the two "modified" Blackhawks were used and two HH-47 Chinooks were used as well. The HH-47 was used to refuel the Blackhawks and go in and get the crew of the Blackhawk that went down.
 
One thing you're all forgetting is that the CIA had a presence on the ground. It is not inconceivable that they were able to set up a covert fuel dump/s on either the ingress or extraction routes in advance.
 
Also, there is a possibility that the stealth helos could be operated by CIA and not by the Navy or Marines.
 
Grey Havoc said:
One thing you're all forgetting is that the CIA had a presence on the ground. It is not inconceivable that they were able to set up a covert fuel dump/s on either the ingress or extraction routes in advance.

TF160 and other Army/JSOC units drill to do FARPs day in, day out. It's their bread and butter. Special Activities does not. JSOC has more than one unit dedicated to tactical intelligence collection supporting specifically this kind of operation. You can't kick down UBL's door unless you know what it's made of, and what kind of lock is on it. You don't land a C-130 on a desert strip without making sure the ground can hold the weight. These are the guys that go in ahead of an operation and collect that information.

The point though was that either:
1. It was a modified UH-60 and either FARP'd or staged/refueled out of Ghazi
2. It was not a UH-60 and had greater range/payload
 
running with the idea that this stealth helicopter is not based on a UH-60...

My knowledge of utility/troop carying helicopter performance specs is limited, so appologies if it's lazy of me to ask this. Which (if any) helicopters are currently on the market that would have the range and load carrying capacity to perform this mission without covert in-theatre refueling?

Top be clear, the reason for asking is just to get a feel for the size and performance characteristics necessary to complete the mission without FARP's (I'm not searching for alternative benchmark models that were "pimped for stealth").

EDIT
NB// V-22's, tandem rotor choppers or conventional choppers with stealth-destroying external tanks don't count!
 
quellish said:
TF160 and other Army/JSOC units drill to do FARPs day in, day out. It's their bread and butter. Special Activities does not. JSOC has more than one unit dedicated to tactical intelligence collection supporting specifically this kind of operation. You can't kick down UBL's door unless you know what it's made of, and what kind of lock is on it. You don't land a C-130 on a desert strip without making sure the ground can hold the weight. These are the guys that go in ahead of an operation and collect that information.

The point though was that either:
1. It was a modified UH-60 and either FARP'd or staged/refueled out of Ghazi
2. It was not a UH-60 and had greater range/payload

Just covering all the angles. B)
 
Catalytic said:
My knowledge of utility/troop carying helicopter performance specs is limited, so appologies if it's lazy of me to ask this. Which (if any) helicopters are currently on the market that would have the range and load carrying capacity to perform this mission without covert in-theatre refueling?

Minimum range for launch and recover at JBad would be about 420 miles. Actual ranges vary with route, reserve, fuel consumption loitering at the target for 30 min, etc. but 420 miles is a good starting point based on probable routes and reserve.
S-92, EH101, NH90 and other helicopters in that class would qualify. The S-92 rotor head does not look at all like the wreckage, unfortunately.
S-92 rotor head:
http://www.flickr.com/photos/wehaveapiperdown69/3629991908/

Wreckage:
http://www.secretprojects.co.uk/forum/index.php/topic,12597.msg123963.html#msg123963
 
Best online EHI-01 EH-101 ;) rotor head pic I could find:

p5707.jpg


Someone said "it IS Sikorsky" - show your working?
 
Thank you Mr Q!

So fairly large birds then, although an NH-90 sized helicopter is not unreasonably large compared to the wreckage footprint. Your previous comment regarding rotor sizes is insightful!

My eye only reckoning would suggest that even with 5 blades on the tail rotor, the swept area of these aerodynamically inefficient looking blades would appear to be too small for a chopper with the necessary size to do this mission without a FARP. I suppose increased tail rotor RPM is a possibility but this runs counter to common sense and historical developments for quiet choppers.

New chopper or not, it seems (to me) most likely that FARP's were involved and this mission was much more complicated than my first glance assumption of SEAL team six, Casey Ryback & the Littlest Hobo jumping in a fleet of stealthy helicopters and just flying in and out.

Some members have great skill in dragging out dimensions from photographs (Tagboard did an excellent job in a thread on the RQ-170) so I'll repeat a request for help on determining rotor sizes, if only to prove my eye only reckoning is worthless.

EDIT
addition of feeble canine humor
 
Gridlock said:
Best online EHI-01 EH-101 ;) rotor head pic I could find

http://ftp.rta.nato.int/public//PubFulltext/RTO/MP/RTO-MP-024///MP-024-08.pdf
 

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For what it's worth, I had a couple of Black Hawks in our local airport today. According to the fuel caps on them, they do indeed hold 181 USG per tank, so I'd venture to say that it's a good chance the cap in the pic could very well be taken from a Black Hawk.


frank said:
What's the significance of a generic fuel cap? Other than whatever this one went on held 181 USG in that tank?


blackstar said:
Saw this on the NY Times site. Don't think it has been posted here yet.
 
On the main rotor hub: does anyone know if Sikorsky has flown the 5-blade hub for the CH-148 Cyclone? Are there images of that hub?
 
Walter Boyne was on my local TV news yesterday morning. He's the (cough) former director of the National Air and Space Museum. He has a new book out about helicopters. Apparently the gist of it is that the U.S. hasn't done anything good in helos in a long time and he considers it "a shame" that the helicopters used in the bin Laden raid are based on 30+ year-old designs. He cited things like the cancellation of the Comanche and the presidential helo fiasco. He also considered it a shame that the Black Hawks had "bolted on stealth."

There you go.
 
I I had something that needed a good analyzin', I'd hire the whole bloody lot of you!
 
Apophenia said:
On the main rotor hub: does anyone know if Sikorsky has flown the 5-blade hub for the CH-148 Cyclone? Are there images of that hub?

Or you scale up an RAH-66 rotor system, although I have no idea if is scales up or not. Then you have to change out the main gear box. etc., but if you have a set of deep pockets off the primary books... sure why not.
 
A guy called radojavor over at deviantart did this (image via MP.net):

http://www.militaryphotos.net/forums/attachment.php?attachmentid=156245
 

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Grey Havoc said:
A guy called radojavor over at deviantart did this (image via MP.net):

http://www.militaryphotos.net/forums/attachment.php?attachmentid=156245

Wow, that actually makes a lot of sense. A fair amount of LO work on the parts that likely created significant returns, without being massively different. The only place I think this artist missed is the possibility of a rotor hub fairing or perhaps an upward extension of the hydraulics assembly cover to do the same function.

http://www.globalsecurity.org/military/systems/aircraft/mh-x.htm - Also found at MP net an interesting article on rotor noise reduction.
 
Orionblamblam said:
The OBL raid was handled EXTREMELY poorly by the administration, for any purpose beyond Obama-promotion. The purpose of Special Forces raids are not for PR, but to get a job done quietly. The proper response by the administration should have been... utter silence.

Huh:
http://www.usnews.com/news/blogs/washington-whispers/2011/05/13/seals-angry-at-attention-want-it-stopped

U.S. Navy SEALs, like the teams that killed Osama bin Laden, are grateful for nation's show of support but are growing angry with the continued focus on their operation, tactics, and tools, claiming it could jeopardize future raids and their safety.

"My friends in the community tell me they're very glad for the bit of attention they got," said former Pentagon deputy undersecretary Jed Babbin, "but at some point the best way to help them is to stop. You guys in the press have done a good job, but stop for God's sake, stop."
...
"It's my feeling that the administration has aimed a spotlight into one of the darkest corners of our national security apparatus without regard for the damage it might do to its ongoing operations."
 
Orionblamblam said:
"It's my feeling that the administration has aimed a spotlight into one of the darkest corners of our national security apparatus without regard for the damage it might do to its ongoing operations."

http://www.funnyordie.com/videos/8e464776e6/the-navy-seal-who-killed-osama-bin-laden?rel=player


Discovery is running a show right now, "Killing Bin Laden" that has the usual group of talking heads. Nothing all that new in the program, though they do get the name of the operation correct, and explain the crash correctly.
They're using CounterStrike to simulate the raid.
 
If you look at some of the photos of the wreckage - in particular the first few photos, which show the tail propped up against the wall - you may be able to pick out the tail rotor drive shaft. It appears to be a UH-60 tail rotor drive shaft, but:
1. According to people familiar with UH-60 crash investigations, in a crash the tail rotor drive shaft often becomes twisted. This one appeared to be snapped, almost cleanly.
2. The diameter of the shaft appears too small for a UH-60.

Turns out, the UH-60M has a composite tail rotor drive shaft. The new drive shaft was required on the UH-60M:
"The introduction of an all composite tailcone precipitated the requirement for a compatible composite tail rotor drive shaft to provide a suitably matched coefficient of thermal expansion."
http://www.vtol.org/f64_bestPapers/propulsion.pdf

Which makes some sense. If the SHHHHH-60 is a blackhawk with composite components, the UH-60M driveshaft would probably be required for the same reasons.
 
http://www.washingtonpost.com/world/sen-john-kerry-arrives-in-pakistan-for-meetings-that-could-sway-future-us-aid-prospects/2011/05/16/AFJJIZ4G_story.html?hpid=z1

Pakistan to return U.S. helicopter tail, Kerry says
By Karin Brulliard, Updated: Monday, May 16, 11:39 AM

ISLAMABAD, Pakistan — Pakistan has agreed to return the tail of the U.S. military helicopter that malfunctioned during the Osama bin Laden raid, U.S. Sen. John F. Kerry said Monday, part of a “specific series of steps” aimed at reducing suspicion between Islamabad and Washington.

Kerry (D-Pa.) came here to discuss the killing of bin Laden with top Pakistani leaders, in meetings that could influence whether the United States continues to provide billions of dollars in aid to an ally that many in Washington believe harbors Islamist militants.

In the wake of the raid, the two nations’ relationship hovers at one of its worst-ever points. Some members of Congress, outraged that bin Laden found refuge for years in a Pakistan city known for its military academy and bases, are calling for the severance of aid to Pakistan. Pakistani officials, meanwhile, are furious that the U.S. did not tell them in advance of the bin Laden operation, and are facing an angry domestic backlash at the unilateral American action on Pakistani soil.

Kerry, chairman of the Senate Foreign Relations Committee and the most senior U.S. official to visit Pakistan since bin Laden’s death, told reporters in the Pakistani capital on Monday that, “This road ahead will not be defined by words. It will be defined by actions.”

“My goal in coming here was not to apologize for what I consider to be a triumph against terorrism of unprecedented consequences,” Kerry said of raid on bin Laden’s compound. But, he added, “isolated episodes, no matter how profound, don’t jeopardize the larger relationship.”

Kerry said that in meetings with top civilian and military leaders, the U.S. and Pakistan had “agreed on a specific series of steps that will be implemented in order to get the relationship on track.”

The first step in that “roadmap,” as he described it, is that the the tail of the downed helicopter used in the raid will be returned to U.S. custody. The copter experienced mechanical difficulties when landing at bin Laden’s compound. Navy SEALs destroyed part of it before leaving, in an effort to keep the latest U.S. military technology a secret.

But the tail remained intact, and photos of it quickly made their way into public view.

Kerry’s name is widely associated in Pakistan with a recent U.S. assistance package meant to demonstrate a long-term strategic partnership. But with many in Washington focusing on Pakistan’s alleged collusion with insurgents, that funding is now on the line – a development Pakistanis interpret as proof of U.S. capriciousness.
 
Fun thread to read! Tons of good discussion going on :)

Just came across this - some more details on the operation:

http://www.navytimes.com/news/2011/05/ap-raiders-knew-mission-a-one-shot-deal-051711/

Five aircraft flew from Jalalabad, Afghanistan, with three school-bus-size Chinook helicopters landing in a deserted area roughly two-thirds of the way to bin Laden’s compound in the Pakistani city of Abbottabad, two of the officials explained.

...

The Black Hawks were specially engineered to muffle the tail rotor and engine sound, two officials said. The added weight of the stealth technology meant cargo was calculated to the ounce, with weather factored in. The night of the mission, it was hotter than expected.

...

The plan unraveled as the first helicopter tried to hover over the compound. The Black Hawk skittered around uncontrollably in the heat-thinned air, forcing the pilot to land. As he did, the tail and rotor got caught on one of the compound’s 12-foot walls. The pilot quickly buried the aircraft’s nose in the dirt to keep it from tipping over, and the SEALs clambered out into an outer courtyard.

- 'fat cow' FARP was set up by chinooks as mentioned earlier in the thread
- blackhawk modifications had a primary focus of sound reduction, with stealth a second priority which I infer as not too drastic a redesign, with changes around the tail, main engines, and probably nose
- modifications extremely inhibited performance (or they decided to push the load out to the limit, actually most likely both) which isn't too suprising
 
http://www.washingtonpost.com/world/national-security/cia-flew-stealth-drones-into-pakistan-to-monitor-bin-laden-house/2011/05/13/AF5dW55G_story.html

CIA flew stealth drones into Pakistan to monitor bin Laden houseBy Greg Miller, Updated: Tuesday, May 17, 9:27 PM
The CIA employed sophisticated new stealth drone aircraft to fly dozens of secret missions deep into Pakistani airspace and monitor the compound where Osama bin Laden was killed, current and former U.S. officials said.
 
Damn, I was just about to post this too. Oh well. From what I read in the article they ARE NOT talking about the RQ-170.
 
John21 said:
Damn, I was just about to post this too. Oh well. From what I read in the article they ARE NOT talking about the RQ-170.

Probably something a lot smaller, perhaps some MAV-type drone, or one of the smaller Aerovironment UAVs.
 
John21 said:
Damn, I was just about to post this too. Oh well. From what I read in the article they ARE NOT talking about the RQ-170.

The article mentions the RQ-170, but does not cite a new source other than the one mentioned earlier in this thread. It's important to try and figure out when a reporter is using direct information (he's got some quotes and paraphrases that are attributed to anonymous sources, but indicate that he did talk to somebody), and when the reporter is speculating. He may only be speculating that the RQ-170 was involved and not actually know that.
 

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