Category Archives: Stealth Black Hawk

Take a look at the following screenshots taken from a Youtube video taken with a helmet-mounted camera by US Special Forces (Delta Force’s A Sqn) rescuing Italian and Polish contractors from a hideout in Iraq with the help, once again of the 160th SOAR, on Jun. 8, 2004.

The first thing  I thought when I saw the footage is that sometimes history repeats itself.

Here the full video. The impact is clearly visible at mins 1.23 and 1.49:

Contractors had been abducted in Baghdad on Apr. 13, 2004 along with another Italian citizen, Fabrizio Quattrocchi, who was killed by kidnappers on Apr. 14.
A daring rescue operation was put into action as soon as coalition forces gathered reliable information on the location where the hostages were being held. As the footage shows, the 4 MH-60s (using c/s “Prince 61 – 64”) along with 4 escorting AH-6s (“Granite 71 – 74”) flew  over Baghdad then approached fast and low the compound where the workers were held.
While the third MH-60K (“Prince 63”) was flaring before touch down (with a dust cloud raised by the preceeding choppers) it hit the comp0und’s wall with its tail rotor beam/stabilizer. Fortunately, unlike what happened in Afghanistan during Operation Neptune’s Spear, the Black Hawk did not break apart and it was able to land allowing the SOF operators to leap out and to rescue hostages. The operation was successful (as the OBL raid was) and the helicopter was (probably) able to return to its base (the video doesn’t show this phase so we can’t be completely sure it didn’t suffer some structural damage).

Anyway, what happened during the 2004 rescue in daylight conditions, seems like a confirmation to what I’ve already suggested yesterday (pt1) describing the possible root causes of the crash landing of the Stealth Black Hawk during the OBL raid: the helicopter might have hit the compound’s wall on fast approach for landing at night with NVG in a particularly long and exhausting mission. A lesson to be learned for future special ops involving low level approaches to compounds surrounded by walls?

An interesting article published yesterday by the Associated Press and commented by Wired/Danger Room, provided some interesting details about the Osama Bin Laden raid. Indeed, anonymous government sources have told the story to the AP even if information they disclosed, raise more questions…
Anyway, first of all, I can’t help but notice that my possible explaination of Operation Neptune’s Spear (OBL raid’s name), published on May 6, was not disproved by facts disclosed so far!

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.

Good. The departure aerodrome is Jalalabad (my guess was right)  and there were also 3 Chinooks. Let’s have a look to what I wrote on May 6:

“I think there are two possibilities: both [helicopters involved in the raid] were Silent/Stealth/Upgraded/Modified/etc. Black Hawks; or 2 were Stealth Black Hawks and Stealth Chinooks. I don’t believe that “normal” MH-47s were involved as some media speculated (for the above mentioned considerations on the stealthiness of the formation) so, I’m almost sure only new Black Hawks were used. However, since we now know that a Black Helicopter exists, I can’t completely rule out the possibility that, along with a Stealth Black Hawk, somewhere there’s also some sort of modified Stealth Chinook flying“.

Since the officials confirmed that 3 Chinooks were involved and given that a mixed formation of stealth and non-stealth helos would have rendered the entire formation clearly visible on radars and audible from distance, I believe that there must be also a modified MH-47 flying with the 160 SOAR. Unlike the Black Hawk, we have no photographic evidences of it, but I think that their existence is somehow confirmed by the fact that the officers admitted their presence on the scene. Furthermore, it is quite obvious that the sources are trying to deceive the public opinion when they say to the AP journalist that:

The Black Hawks were specially engineered to muffle the tail rotor and engine sound, two officials said.

You can’t reduce noise by modifying only the tail rotor. Even the main rotor had to be fixed. And what about the anti-radar finish to enhance stealthiness? In my opinion, as explained in the last post on this subject, the Stealth Black Hawk is a highly modified version of the UH-60 helicopter.

I’ve asked once again to Ugo Crisponi to prepare a sketch of how a Stealth Chinook might look like by applying more or less the same modification used for the Stealth Black Hawk.

The same AP article then gives some details about the Stealth’s crash landing:

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.

On this topic I had a chat with a friend of mine, who’s a former helicopter combat pilot with some Tour of Duty in Afghanistan. He’s quite skeptical about the “weather factor”: Abbottabad is “only” 4.000ft AMSL and at night, the temperature is always (well) below 30° C. Even a heavy modified helicopter should not have problem hovering over the compound. Hence, there could have been three kind of “root cause” for the crash landing:

1) flying a very risky mission at night with Night Vision Goggles, the pilots could have lost situational awareness and impacted the compound’s wall while approaching it for landing. This would explain why the tail is cut as images show
2) the helicopter, flying at lower altitude than the other Stealth Black Hawk, was hit by wake turbulence generated by the other chopper’s rotor. “It’s a very dangerous situation” my friend told me “since the turbulence hits both the main and tail rotor, giving almost no chances to react”
3) there was a “recirculation condition”: exacerbated by proximity to walls or cliffs or trees, this occurs when the air passes down through the rotor disc, hits the ground, moves out horizontally, hits the wall, goes up and then gets sucked down again through the rotor. You then have air that is already moving down coming through the disc and this leads to a greater power requirement which can then make the effect worse. This accident may not have been helped by the modifications to the tail rotor to make it stealthy that also reduced its efficiency and need for more power. It may not have been helped by pilot’s under pressure,
coming in low and fast, possibly with obscured vision behind the first aircraft throwing up dust/sand.

This is how the Stealth Black Hawk (dubbed also “Silent Hawk”) could look like based on the analysis of all the information available to date. It is sensibly different from the previous sketch; if you read below you’ll understand why.

After publishing the various famous sketches of the possible shape of the modified Black Hawk (dubbed “Stealth Black Hawk” or “Silent Hawk”), together with Ugo Crisponi I’ve continued studying pictures, suggestions, comments and all the information available about the mysterious helicopter that performed a crash landing during the Osama Bin Laden raid. While some hundred thousands readers all around the world, along with major media worlwide, much appreciated our work, others argued that we were giving bad guys some valuable information about a “black project”. Actually, the sketches were based on my initial analysis of the publicly available pictures, that Ugo was able, through a series of attempts, to “translate” into a realistic shape. So, what we did could be done by anybody willing to spend some time studying images and thinking to all the possible modification that could make a Black Hawk, if not stealth, more silent.

Furthermore, a far more in-depth study that could be used to project a Low Observability UH-60 is already in the Public Domain and freely available on an official US military website. It was issued in 1978 by Sikorsky Aircraft Division for the US Army Research and Technology Laboratories and it is titled: “STRUCTURAL CONCEPTS AND AERODYNAMIC ANALYSIS FOR LOW RADAR CROSS SECTION (LRCS) FUSELAGE CONFIGURATIONS”. It shows that first attempts to give the UH-60 some stealth capabilities dates back to 33 years ago. Although I can’t expect the fuselage concepts for low radar cross section aircraft configurations designed at the end of the ’70s still apply today, the basic concept around them could be still useful to imagine a few modifications to the Stealth Black Hawk profile as I initially thought it.

Noteworthy, the shape suggested in 1978 document reminds that of an F-117 rather than that of a more modern stealth, like an F-22. This is consistent with the article published on Army Times titled “Mission helo was secret stealth Black Hawk” according to which the helo has “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”.

Here below, you can read some excerpts of the above mentioned public document that I used with Ugo Crisponi of Aviation Graphic to review the sketch.

Three fuselage configurations for low radar cross sections were developed by the Applied Technology Laboratory. […] The main rotor pylon fairings and tail surfaces aft of a tail fold hinge for each configuration were the same as those for the baseline UH60A. In the initial portion of this study, the weight and costs (percent of total) were developed for sections of the baseline UH60A fuselage. […] Structural concepts were developed which could be applied to each configuration using conventional materials. An assessment of safety, fail-safety, and maintainability for each configuration was performed. The change in structural weight and the percentage change in cost for each configuration using the concepts developed were compared to those of the baseline. One concept was selected and applied to the three configurations.
Having selected the structural concept with the lowest weight change and percentage cost change for the three fuselage configurations, the effect on weight and costs using advanced materials was developed and applied to the three configurations. To evaluate the impact of the results of the fuselage study, design attributes of six helicopters were developed using a Helicopter Design Model (HDM) computer program.

Three low radar cross section fuselage configurations for this study were developed by the Applied Technology Laboratory. The first configuration slightly modified the nose section from the baseline configuration; the second configuration changed the fuselage shape along the lines of a truncated triangular prism; the third extended canted flat side shaping throughout the fuselage. The tail surfaces and main rotor pylon fairing were the same as those of the baseline UH60A.

CONFIGURATION 1

This configuration alters the baseline fuselage forward of the mid-cabin section (the cockpit). Although this configuration is different from the baseline, the internal structure must be compatible with the forward cabin to avoid a heavy joining structure. The overall length is slightly increased due to this configuration.

CONFIGURATION 2

This configuration is basically a trapezoidal cross section airframe having sides canted inward 30° and made up of flat exterior structural panels. This configuration is wider at the bottom of the fuselage and narrower at the top of the fuselage than the baseline. This configuration is slightly longer than the baseline UH60A, and its overall height is slightly larger than the baseline. The increased length, width, and height of Configuration 2 does not allow an aircraft of this size to meet the air transportability requirements of the baseline. The narrow upper fuselage causes the pilot and copilot seats to be spaced closer to each other, and shoulder room in the main cabin is decreased. The main cabin floor is approximately 6 inches higher than the baseline from the ground. The increased floor-to-ground height causes difficulties for combat troops to enter or leave the aircraft quickly. Minor modifications of the mold lines for the transition and tail-cone sections were made to properly house the tail rotor shaft of the baseline UH60A.

CONFIGURATION 3

This configuration is basically a flat side cross section airframe having sides canted inward 50 and is tapered in width from a narrow cockpit section to a transition section as wide as the baseline UH60A. The tail-cone is a rectangular section which is narrower than the baseline. The narrow cockpit causes the pilot and copilot seats to be spaced closer to each other; space for four-across seating in the main cabin is decreased. The cockpit and main cabin floors are at the same height from the ground as the baseline. The slope of the windshields may cause problems of visibility for the flight crew. Minor modifications of the mold lines for the transition and tail-cone sections were made to properly house the tail rotor shaft of the baseline UH60A.

ADVANCED MATERIAL APPLICATION

Advanced composite materials can be used in the construction of the three fuselage shapes considered in this study. Studies,  have shown that the use of composite materials can reduce both fuselage weight and cost. The fuselages of this study are relatively lightly loaded compared to fixed-wing aircraft. To efficiently use advanced materials in the fuselages, very light composite skins are used in the post-buckled stress state. […]

CONCLUSIONS

Structural concepts developed for the three LECS configurations showed that extensive reshaping, as exemplified by Configuration 2, would increase fuselage weight from that of the baseline UH-60A fuselage by 223 pounds and cost by 3.65 percent. When advanced materials were used Configuration 2 decreased
from the baseline fuselage weight and cost by 116 pounds and 3.98 percent respectivdly. Total aircraft performance capability was degraded primarily by drag effects. The aerodynamic analysis indicated that Configuration 2 would have a vertic climb rate at 15 percent of the baseline.  Weight, cost, and performance penalties were less in Configurations 3 and 1 respectively.

Based on the results of this study, the following conclusions are made:

1. The use of advanced materials can result in both weight and cost savings over the baseline fuselage, even with the most severe change in LRCS configurations presented.
2. Without the use of advanced materials, the LRCS Configurations 2 and 3 significantly increase both weight and cost of the total aircraft compared to the baseline UH60A.
3. Minor changes to the nose section of Configuration 1 result in negligible fuselage difference to the weight and cost of the fuselage.
4. Consideration of the total aircraft attributes show that vertical drag penalties appear to be of greater magnitude than the structural weight changes involved with the fuselages of Configurations 2 and 3.
Even with the use of advanced materials, the vertical drag penalty exceeds any weight savings.

The sketch was revised to take the document into consideration (without forgetting it was issued at the end of the ’70s). Even the main rotor was redesigned to make its head slightly larger (with a noise reduction cover sheltering the motion-control technology used to input low-frequency variations of rotor blade pitch-angle, as tested by NASA) .

One last thing worth a mention.

In the aftermath of the crash landing, on May 5, Jon Nowinski, an investigative reporter and founder of the Smoking Gun Research Agency (www.sgra.org) sent me an email to let me know that:

[… ] over the last few days there has been an increased number of late-night helicopter flights to the Sikorsky plant. While that doesn’t entirely stand out as odd, it is interesting to note that normally these flights are related to testing aircraft, as well as consistant with what happens when a Sikorsky helo goes down in military action. After an accident like that, military investigators and officials frequently come out to the Sikorsky plan for a debriefing during which they review the operation

We already know that secrecy was of paramount importance in Operation Neptune’s Spear. The US willingness to use Stealth Black Hawk helicopters during the Osama Bin Laden raid is a measure of the importance of a mission involving Special Forces, aircraft, ships, drones, satellites and who knows how many new/unknown technologies, deep inside a foreign country’s territory as if Pakistan was the worst American enemy.

As we know, President Barack Obama gave the go ahead to the operation on Apr. 29 at 08.20AM, in the Diplomatic Room, before leaving for Alabama. According to the reports, he had met his “national security adviser Thomas Donilon, counter-terrorism adviser John O Brennan, and other senior national security aides to go through the detailed plan to attack the compound and sign the formal orders authorising it”.

As Italian news station Rainews noticed, few hours later, as Obama arrived in Cape Canaveral, Florida, he quite “stealthily” gave a piece of paper to Air Force General Ed Wilson (Commander, 45th Space Wing, and Director, Eastern Range, Patrick AFB, Fla.) while they shook hands. Gen. Wilson, took another paper from his pocket and, in the same way, put it into the President’s palm.

Even if it is impossible to guess what kind of information they exchanged in such a weird manner, for sure the way the information was transferred as well as the timing of the episode raise some questions. Rainews Director Corradino Mineo ventured the suggestion that the exchanged information could be related to the OBL raid, demonstrating how keeping it confidential was the number one priority of US government.

Even if I find it intriguing, I think this would be a rather clumsy way to exchange secret orders or other intelligence information: in front of cameras and not, for example, during an extremely quick private meeting. Anyway, at the same time, I can’t completely rule out the possibility that those papers contained something as important as Operation Neptune’s Spear orders. However if “mission critical” information must be exchanged on paper to ensure confidentiality, maybe time’s arrived to review Net Centric Warfare doctrine and Joint Battlespace Infosphere concept (just to name but two) which are based on an integrated, secure, internetworked information flow…

So far, with the help of Ugo Crisponi, I’ve been able to offer my readers a possible view of the Stealth Black Hawk involved in the Osama Bin Laden’s raid. However, although I’ve already underlined since my very first post on this topic that there MUST be much more flying assets involved in the complex mission, I think that it could be interesting to draw a possible “picture” of all the aircraft taking part in Operation Neptune’s Spear. This is obviously just one of the ways to piece facts together but it seems to me the more reasonable for a series of things I’ll briefly discuss. First of all let me stress a concept: the Stealth Black Hawk that crashed in the OBL (Osama Bin Laden) compund was not so stealth to be completely invisible. Indeed, to answer again to my famous Twitter friend @PrimorisEra (for an interesting comment on her intriguing “saga”, read here): I agree, no aircraft can achieve complete stealthiness; choppers in particular, with all those rotating parts, are not so easy to hide to radars.

Not being completely radar-evading, the choppers (I believe more than 2) were covered by some EW platforms, probably in the form of either EA-6B Prowlers from USS Enterprise or EA-18G Growlers from USS Carl Vinson, both currently in the North Arabian Sea. I’m pretty sure that a US supercarrier in the area played an important role in the entire operation: being involved in Operation Enduring Freedom, it launches on a daily basis its assets belonging to the Carrier Air Wing along the Transit Corridors to Afghanistan. Any activity along the TCs across Pakistan would appear absolutely normal to the Pakistani controllers. For the same reason, it is possible that at least an E-2C Hawkleye and a pair of Super Hornets (F-18E or F) launched by the Big-E were used to provide respectively AEW (Airborne Early Warning – air space management) for the entire operation and DCA (Defensive Counter Air): the mini-AWACS could detect any Pakistan AF fighter being scrambled against the formation of helicopters bringing the US Navy Seals to Abbottabad and the “Rhinos” could be directed against the interceptors to provide cover.

1. Where did the helo depart from? Most probably, Jalalabad. The RQ-170 was seen at Kandahar so I assume it operated out of KAF.
2. How many helicopters involved? More than 2, maybe 4 (plus spares?).
3. How many were (let’s say) “stealth”? All of them. If one or two were stealth, both both those approaching Osama Bin Laden’s compound had to be stealth to ensure “stealthiness” of the formation.
4. Which models? I think there are two possibilities: both were Silent/Stealth/Upgraded/Modified/etc. Black Hawks; or 2 were Stealth Black Hawks and Stealth Chinooks. I don’t believe that “normal” MH-47s were involved as some media speculated (for the above mentioned considerations on the stealthiness of the formation) so, I’m almost sure only new Black Hawks were used. However, since we now know that a Black Helicopter exists, I can’t completely rule out the possibility that, along with a Stealth Black Hawk, somewhere there’s also some sort of modified Stealth Chinook flying.
5. Supporting aircraft? Many: KC-130Js provided air-to-air refueling to the assets (notice: all probe equipped), an RQ-170 provided detailed FMV of the target area, an RC-135 Rivet Joint performed SIGINT activity, an EC-130H provided EW jamming communication, Early Warning/Acquisition radar and navigation systems along with the above mentioned Prowlers/Growlers; an E-2 provided AEW, while an E-6 ABNCP acted as an airborne command post (Airborne Command, Control and Communications Platform). MV-22s (or C-2?) were waiting for the command to return to Jalalabad to carry OBL body on board Carl Vinson. MH-47s and other “back up” aircraft could be present as well, both on the ground and CAPping “on call”. BTW all aircraft orbited within the Afghan airspace.

As said, this is obviously just one of the possible descriptions of the mission. If I’ve missed something or if you think something must be fixed, just let me know. Even if I can’t be sure on the actual number of involved aircraft, I’m more than sure it was an extremely complex operation!