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The U.S. Sold This Unique Stealth Drone Called 'Scarab' To Egypt In The 1980s

The SC

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Earlier in 2018, Scaled Composites, an aviation company well known for its advanced and novel designs, and now a division of Northrop Grumman, quietly posted a series of previously unreleased images online of a stealthy reconnaissance drone called the Scarab. Decades earlier, Scaled had built an initial batch of the unmanned aircraft on behalf of what was then Teledyne Ryan Aeronautical, who, in turn, sold them to just one customer, Egypt.

Teledyne Ryan, which itself became part of Northrop Grumman in 1999, developed the jet-powered, ground-launched Scarab, also known as the Model 324, specifically to meet Egyptian requirements in the early 1980s. Scaled was directly involved throughout the entire design and flight test processes.

It’s not entirely clear what the specific impetus was for Egypt’s interest in the drone was, but in 1978, then-Egyptian President Anwar Sadat had signed the Camp David Accords with then-Israeli Prime Minister Menachem Begin. This led to a formal peace treaty between the two countries the following year. It also came along with a pledge by the United States, which had mediated the deal, that it would provide both countries with significant amounts of often advanced military aid.

To this day, these two countries are among the top recipients of American foreign military assistance. Scarab could have been attractive to the Egyptians as it would have provided an advanced aerial reconnaissance tool that would have been highly survivable against most, if not all of the air defense threats in the broader Middle East region at the time. This means that it could collect details imagery of enemy positions without the need for air superiority to ensure its survival.


Scaled Composites
Scaled Composites employees carry a nose section for a Scarab at the company's plant in 1988.

The Scarab was definitely a state-of-the-art design at the time with a purpose-built stealth shape. Teledyne Ryan already had years of experience experimenting with stealthier drone designs for the U.S. Air Force, including the AQM-91 Firefly, also known as Compass Arrow, and YQM-98A, or Compass Cope.

The Model 324 also featured a lightweight composite airframe, which helped improve its performance and further reduce its radar cross-section. Export laws prevented Teledyne Ryan and Scaled from using carbon fiber, so the latter firm devised a novel “composite sandwich panel structure with fiberglass and Kevlar for skins and PVC foam cores,” according to Scaled’s website.


Scaled Composites
Scarabs under construction at Scaled Composites.


Scaled Composites

“Even with these lower-performance materials, Scaled engineering a wing that was strong and stiff enough to accommodate all of the required flight loads,” the company’s profile on the drone continues. “In fact, the vehicle experienced an extreme negative g pitch-over due to a control problem on the first flight, and did not fail any composite components during the ensuing out-of-control event.”

Other components of the unmanned aircraft proved extremely durable, as well. This was in part a result of the need for the drone to survive being repeatedly blasted into the air from a ground-based launcher using a modified rocket booster from a Harpoon anti-ship missile.


Scaled Composites
A Scarab on its launcher.

“On one occasion, the 18,000 pound-thrust launch rocket motor exploded at launch and pitched the vehicle approximately 10 feet vertically into the air,” Scaled’s website notes. “The vehicle then fell back into the incinerating launcher and bounced out into the desert. The integrity of the fuel tank was not compromised during this event.”

The entire system included a truck-mounted ground control station and power generation system that also served as the prime mover for the trailer-mounted launcher. It's not clear who built the 8x8 all-wheel-drive truck, but it appears to have an independent suspension system very reminiscent of a family of designs the Standard Manufacturing Company was developing at the same time. The U.S. military tested a variety of the Standard Manufacturing vehicles, including a wheeled self-propelled anti-aircraft gun called Excalibur, but never adopted any of them.


SDASM Archives
The complete Scarab system.

The six-wheeled trailer also had an auxiliary motor to allow crews to more readily move it into its actual launching position when detached from the truck. The truck-and-trailer combination had a maximum speed of 52 miles on improved roads, but also had some off-road capability. A complete system with a Scarab on the launcher was also small enough to fit inside a C-130 cargo plane.

After blasting off from its launcher, Scarab could reach a top speed of nearly 650 miles per hour and an altitude of up to 40,000 feet, depending on its predetermined altitude and mission profile, and could carry a payload of more than 250 pounds over a total distance of 1,400 miles. When it returned to base, its small jet engine would cut out and a parachute would deploy. The drone would eventually sail down to earth, landing on a set of inflatable airbags hidden inside the fuselage and wings.


Teledyne Ryan
The recovery sequence for the Scarab.

Teledyne Ryan
The Scarab's Air-Bag Impact Attenuation System (ABIAS), which cushioned it when it hit the ground after parachuting down to Earth.

Crews on the ground had a line-of-sight command link that they could use during the beginning and end of the drone's flight. Beyond the range of that control station, the drone would use pre-programmed waypoints and an inertial navigation guidance system to get to and from the intended area. Later on, Egypt upgraded the Scarabs with a GPS-assisted guidance capability.

As delivered, the Scarabs could carry either a KS-153A optical camera or a Loral D-500 infrared laser camera system. The latter used the laser for infrared illumination, allowing the camera to capture images at night. Both cameras, however, employed wet film that required processing after the mission was over. The drone could not transmit any imagery back to base during flight.


Teledyne Ryan
A graphic showing a typical mission profile and operaional setup for the Scarab.

Egypt's President Sadat, who was assassinated in 1981, never got to see the Scarabs and almost certainly didn’t initiate the program. Scarab’s first flight occurred in 1987 and Sadat’s successor, President Hosni Mubarak, accepted the first examples the following year.

Scaled Composites built a total of 29 Scarabs for Teledyne Ryan, which shipped them to Egypt and trained members of the Egyptian Air Force how to fly them. Teledyne Ryan built another 30 Scarabs independently as a second-run and delivered those to Egypt as well. It was the first time Teledyne-Ryan had exported an unmanned aircraft of any kind, which the U.S. military had not adopted, to a foreign country. The Egyptians only established one unit to operate the drones at Kom Awshim Air Base, approximately 50 miles south of Cairo.


via GlobalSecurity.org
An Egyptian Scarab launcher in action.

In 1988, the U.S. Air Force, Navy, and Marines did join together to develop an air- and ground-launched derivative that could be employed both as a target drone and an unmanned reconnaissance platform. Unfortunately, in 1993, the Navy and Marines dropped out of the program.

The Air Force could not afford to purchase the drones, then known as the BQM-145A Peregrine, by itself and subsequently canceled the entire project later that year. The Peregrines lack the visually distinctive hump the Scarabs have on top of their rear fuselage, with their twin air intakes being arranged pectorally instead of having a single intake mounted dorsally.


Workers roll out one of the prototype BQM-145As.


SDASM Archives
An undated photo of an F-4 Phantom II fighter jet, privately owned and carrying the US civil registration code N420ES, with a BQM-145A on its centerline pylon during a test.

Of the 59 Scarab drones the Egyptians received, they reportedly never even uncrated 50 of them, according to Scaled. The nine operational examples did fly some 65 operational missions, but there’s no information about what areas they flew over or for what purpose. There are reports that during Operation Desert Storm, the U.S.-led coalition considered asking the Egyptians to commit the Scarabs to help increase overall reconnaissance coverage. True or not, the conflict ended before the drones went to work, though.

Regardless of their operational activities, the delivery of the drones to Egypt caused something of a stir inside and outside the United States. The biggest concern was that Egyptians might try to modify the Scarabs into stealthy ground-launched cruise missiles that could have presented a significant threat to other countries in the region and potentially have a destabilizing effect.

The Missile Technology Control Regime, a voluntary arms control arrangement covering missiles and unmanned aircraft, which was in place at the time, only prohibits the export of systems that can carry a payload of more than 1,100 pounds to distances greater than 185 miles. This would not cover the Scarab with its stated payload capacity, though it might be possible to increase the payload at the cost of overall range. Either way, Teledyne Ryan did not sell Scarabs to any other customers.


SDASM Archives
An Egyptian Air Force CH-47 Chinook helicopter recovers a Scarab after a launch. The drone's deployed airbag landing system is visible in black under the fuselage.

The exact status of the remaining Scarabs is unclear. As of the late 1990s, Teledyne Ryan was still actively supporting the program in Egypt. After Northrop Grumman bought the firm in 1999, it took over that support contract.

“We are working on a contract with the Egyptians to do upgrades on that aircraft, we are negotiating that as we speak,” Rick Ludwig, then-Director of Unmanned Systems Business Development for Northrop Grumman Integrated Systems, told FlightGlobal in 2006. “They still fly that aircraft about once a month.”

The next year, Northrop Grumman said it was still in talks with Egypt over potentially upgrading the Scarabs, to include new guidance systems and sensors. The addition of digital still or video cameras and a two-way satellite data link to send that imagery back to base in near real time could have significantly improved the drone’s capabilities.
The video below includes footage of a Scarab during testing, beginning at 5:33 in the runtime, followed by clips of the air-launched BQM-145A Peregrine.

..

At this point, the Scarabs, many of which may have been sitting in storage for decades, may be too expensive and impractical to modernize and put to more active use. The idea that the Egyptian Air Force was only flying one of these drones once a month a decade ago doesn’t suggest it was particularly invested in retaining anything but a token capability.
All told, the Scarab’s story may end in relative obscurity.
..
https://www.thedrive.com/the-war-zo...tealth-recon-drone-called-scarab-in-the-1980s
 

Mithridates

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by reading this article one question comes into my mind. we know an stealth plane/drone supposed to bounce of the radar waves in a direction away from the source, also we know that glass fibers (which is the main material of the Scarab structure) are transparent to the radar. so if radar waves can penetrate through the structure and hit internal instruments and engine which are not transparent to it, the radar possibly can detect the drone??
@gambit sir can you help to understand this??
 

Blacklight

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by reading this article one question comes into my mind. we know an stealth plane/drone supposed to bounce of the radar waves in a direction away from the source, also we know that glass fibers (which is the main material of the Scarab structure) are transparent to the radar. so if radar waves can penetrate through the structure and hit internal instruments and engine which are not transparent to it, the radar possibly can detect the drone??
@gambit sir can you help to understand this??
Very interesting question! Looking fwd to an answer from someone more knowledgeable on this topic.
 

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@Bilal Khan (Quwa) this is definitely coincidence but just look at the similarities with Ra'ad. A case of requirements and constraints dictating a design even though decades apart by completely different people.
 

The SC

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Very interesting question! Looking fwd to an answer from someone more knowledgeable on this topic.
Export laws prevented Teledyne Ryan and Scaled from using carbon fiber, so the latter firm devised a novel “composite sandwich panel structure with fiberglass and Kevlar for skins and PVC foam cores,” according to Scaled’s website.


All this from a low-temperature cured non-autoclaved structure, viewed by many skeptics as inappropriate for this class vehicle.

https://www.scaled.com/portfolio/scarab/
 
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The SC

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kevlar is also transparent to radar. the question is how PVC acts against radar.
Not PVC that was used..but PVC foam..

Broadband radar absorbing sandwich structures with enhanced mechanical properties

A fiber column reinforced sandwich absorbing structure has been investigated to achieve broadband absorption at microwave frequencies. It is indicated that the broadband absorption with the reflection less than −10 dB can be achieved from about 2.6 GHz to 21 GHz. The absorption mechanism has been analyzed using the equivalent circuit model and the key parameter study has also been performed. Two samples were fabricated and experimental measurements had been conducted to evaluate the absorbing and mechanical properties. The results indicated that the introduction of the fiber columns in the sandwich structure could remarkably improve the mechanical properties, and has little influence on the absorption. Furthermore, the absorber was quite lightweight because the volume of the foam was about 70.6% in the completely sandwich structure. It is therefore expected that this multifunctional composite structure may find practical applications, such as the stealth technology, and electromagnetic shielding.

https://www.sciencedirect.com/science/article/pii/S2211379718318394
 

Mithridates

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Not PVC that was used..but PVC foam..

Broadband radar absorbing sandwich structures with enhanced mechanical properties

A fiber column reinforced sandwich absorbing structure has been investigated to achieve broadband absorption at microwave frequencies. It is indicated that the broadband absorption with the reflection less than −10 dB can be achieved from about 2.6 GHz to 21 GHz. The absorption mechanism has been analyzed using the equivalent circuit model and the key parameter study has also been performed. Two samples were fabricated and experimental measurements had been conducted to evaluate the absorbing and mechanical properties. The results indicated that the introduction of the fiber columns in the sandwich structure could remarkably improve the mechanical properties, and has little influence on the absorption. Furthermore, the absorber was quite lightweight because the volume of the foam was about 70.6% in the completely sandwich structure. It is therefore expected that this multifunctional composite structure may find practical applications, such as the stealth technology, and electromagnetic shielding.
https://www.sciencedirect.com/science/article/pii/S2211379718318394
i'm not questioning the capability of scarab drone, i'm just interested in this drone because our new cruise missile will look exactly like it. so i just want to understand how much it's immune against radars.
BTW it was a good read so thank you.
 

gambit

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by reading this article one question comes into my mind. we know an stealth plane/drone supposed to bounce of the radar waves in a direction away from the source, also we know that glass fibers (which is the main material of the Scarab structure) are transparent to the radar. so if radar waves can penetrate through the structure and hit internal instruments and engine which are not transparent to it, the radar possibly can detect the drone??
@gambit sir can you help to understand this??
Short answer: Yes. Definitively.

Long answer...

Let us take a look at the AN/APG-79 AESA radar...



Why does the array canted slightly upward?

Because the radome must be radar transparent -- pass thru -- otherwise the radar system would not work. But this is a negative as well. The radome being transparent mean it is pass thru IN BOTH DIRECTIONS. A external signal, being at the right pass thru freq, can reflect off the array, pass thru the radome again, exit the radome, and reveal the aircraft's position. To counter this situation, the -79's array is slightly canted upward so that any possible reflected signal will not return to source direction. The system being AESA with electronic beam steering can point straight ahead or in any direction, so the array's canted degree does not affect radar operations.

Same pass thru principles applies to any material used to cover up anything. Whether this drone is pass thru enough or not, I will leave that research for others, but as far as the laws of physics go, if this pass thru is true, the drone will be detected.
 

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