Leading Systems' ancestors of MQ-1 Predator


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I've searched the forum and did not find anything substantial on Abe Karem's designs that led to the massively successful MQ-1 Predator.
I know one of the first designs was Amber, under the TEAL RAIN program, which started life as a tube-launched cruise missile/ISR platform, with a folding wing on top of the fuselage.
There are later designs, including Prowler, GNAT, and some odd-looking skewed-wing vehicle. I remember finding some information in an old Air and Space magazine 2-3 yrs ago.
Can you share some info on this topic?
Actually there's a whole bunch of information over at The Bar:

Yeah, i posted there last week. That's actually what spiked my curiosity.
Predator A is probably the most successful UAV ever (debatable, and i would list Firebee as close second). But I find very little references in the public domain to its lineage, which is pretty colorful from the little i know.
I mean, Amber launched from a torpedo, had pivoting wing and tails, an incredibly economic in-house developed engine, and could either be used as a surveillance platform or a cruise missile. And the man behind it is pretty interesting too. Abe Karem, was also behind W570, A160 Hummingbird, and now the OSTR entered in the JHL (or whatever they call it these days) competition. It's rare these days that you can actually tie the success of aerospace products to a single personality, the only other one that comes to mind being Burt Rutan (Go CalPoly State University!).
I've looked around, and there isn't much at all on TEAL RAIN - Amber - at all.
The only information I have comes from Andreas Parsch's website


which has the picture attached.
You can see the pylon-mounted wing, meant to rotate for stowage, and simple inverted V-tail. The wingtip and tail surfaces are rounded rather than squared off, giving a rather more graceful appearance. The satellite radome is absent, and so is the third fin usually associated with MQ-1. The latter was probably introduced to address directional stability reduction introduced by the former (pure speculation on my part).


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overscan said:
I've looked around, and there isn't much at all on TEAL RAIN - Amber - at all.

If you're still interested, I do have some information around on it. SOMEWHERE I also have a great interview with Karem from a late 90s issue of Airpower.
is it the two-part Bill sweetman's HALE/MALE article (Vol.15 & 16 IIRC)?
I just got a hold of them recently and they contain more information than found anywhere else, to the best of my knowledge.
AeroFranz said:
is it the two-part Bill sweetman's HALE/MALE article (Vol.15 & 16 IIRC)?
I just got a hold of them recently and they contain more information than found anywhere else, to the best of my knowledge.

No, some stuff from the 80s and early 90s about AMBER, and the Abe Karem interview piece from Airpower. The AMBER material is probably not all that revealing though. I've been meaning to go through it all again in light of some new information on it's relation to Condor and Tier 3.
Machine translation of the text from my web that I did some three years ago:

Early eighties Agency DARPA launched a secret project RAIN Teal, to study pilotless aircraft with long, fueled by a more or less conventional engines. In 1984, californian company Leading Systems received a 40 million contract for the development of the unmanned vehicle Amber, which was used for photographic survey mission ELIN and the role of cruise missiles. Expressed interest in the U.S. Army, U.S. Navy and Marine Corps. 4.6 m, for the margin of 8.54 meters and an empty weight of 335 kg proposed by a team headed by Abraham Karem. It was powered by four-cilinder, water-cooled piston engine with a power of 49 kW, which transmits its power to the two bladed pusher propeller at the rear of the machine. Protect it from damage, vertical tail surfaces in the shape of inverted letter V. The hull was made of plastic and composite materials, primarily of Kevlar, and based on the three-point retractable undercarriage. The wing was mounted on the hull to be in the case of the role of cruise missiles in the ditch on the final phase of guidance to the target. Opening the contract called for three machines Basic Amber A-45 (combat missile) and three B-45 (reconaissance). The first flight took place in November 1986 and main long endurance flights began a year later. The vehicle was able to remain airborne for more than 38 hours. The first information about the project to break into the public in 1987. However, at that time began to have doubts about the U.S. Congress numerous development programs UAV-type aircraft and ordered their consolidation. Project Amber it survived, and in October 1989 took-off the first of seven newly ordered reconnaissance aircraft Amber I. But already a year later were the expenditures for exploration systems, and significantly reduced the program was discontinued. Leading Systems Company was forced to declare bankruptcy and then was purchased by General Atomics.

So far there are two photos of the Amber available to public. First was already posted and the second is this one:


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Am I lucky because I am collecting material for the new Hitechweb update? Yes, I am! :)

01 Amber at El Mirage Airport, circa 1985.

02 GNAT-750 with Rotax 582 engine. Circa 1993. The first aircraft to be flown through a Ku-band satellite link.


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Matej said:
Am I lucky because I am collecting material for the new Hitechweb update? Yes, I am! :)

01 Amber at El Mirage Airport, circa 1985.

02 GNAT-750 with Rotax 582 engine. Circa 1993. The first aircraft to be flown through a Ku-band satellite link.

I've been cleaning/moving the last week or so and have not located the Amber material yet. It may be a lost cause.
I find the first picture especially interesting. You can see several different versions or 'tweaks' of the same version.
It looks like the second and third vehicle from the left in the rear row have small landing gear fairings, whereas the first one doesn't.
The fourth seems to have 'sheared' wingtip shape, while the others have the rounded shape, and then the nose fairing seems slightly flatter on the last vehicle.

AIAA 2010-158
To Boldly Go Where No Unmanned Aircraft Has Gone Before: A Half-Century of DARPA’s Contributions to Unmanned Aircraft
Michael J. Hirschberg
CENTRA Technology, Inc., Arlington, VA 22203

photos (c) Leading Systems and GA ASI


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Way cool! I had never seen the Albatross before, nor the Amber in such a close shot!
Hmmm ???

Just found that in the ARC-Forum under the topic "What is this? Mothballed fuselage identification" posted by 'oldHooker'

This is cut from the corner of a larger picture of an old DC-8-71F that was taken in the desert near Roswell. The photo didn't mention anything about what the smaller fuselage was so I was wondering if anyone here could possibly identify it? Thanks.

the nose kind of resembles a Preditor UAV, but the wingroot on this is at the top of the fuselage... any help greatly appreciated.



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That is the Northrop Grumman Tier II+ HAE UAV mockup at Mojave. Teledyne Ryan won with their Global Hawk. Northrop Grumman later bought TRA (and the Global Hawk program).
aim9xray said:
That is the Northrop Grumman Tier II+ HAE UAV mockup at Mojave. Teledyne Ryan won with their Global Hawk. Northrop Grumman later bought TRA (and the Global Hawk program).

Exactly. Developed by Scaled Composites under the Model 260 study, if memory serves.
MIT Lincoln Labs developed AMBER radar mounted in a AMBER surrogate fuselage attached to a Lincoln Labs Twin Otter.


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I stand corrected. I had no idea that Mr. Karem was behind the Leading Systems (and later General Atomics) drones.

I also didn't realize the impact of his work in general on the adoption of UAVs by all the Armed Forces.

Plus the guy invented the A160 rotorcraft UAV too! Much respect. :-X Thanks VTOLicious for sharing this article.
Welcome Skyblazer, Karem is an interesting person indeed.

...for the sake of this topic, some quotes from the Air&Space article:

1) The Albatross:

The trio produced a UAV demonstrator that was feather-light—it weighed only 200 pounds—and would carry a television camera in its nose. Hertenstein contributed avionics and ground control, and, Karem says, “tremendous expertise in flying his automated model aircraft without crashing.” According to DARPA calculations, it would stay aloft a stunning 56 hours. Karem named it Albatross.

2) The Amber:

DARPA ended up funding the Albatross flight tests. The drone’s exceptional performance led the agency in 1985 to contract with Karem’s new company, Leading Systems Inc., to develop a larger endurance UAV the agency named Amber.

Thus were the seeds of the drone revolution sown. The Predator, though nearly twice as large, is a direct descendant of Amber, as their near-identical configurations suggest. Amber’s thrust came from a two-blade wooden propeller at the rear of the fuselage. Its tricycle landing gear retracted into its body. The V-shaped stabilizers at its tail pointed downward. Karem chose that distinctive feature mainly for aerodynamic stability but also because, in a rough landing, the stabilizers could hit the ground and skid, keeping the propeller blades from shattering on the runway.

Like the Albatross, Amber was radio controlled and could be configured to take off and land like conventional aircraft or fold its wings and stabilizers for launch by rocket from a canister. Most ingenious of all, Amber could be recovered by putting it into a “deep stall”—a feature used in free flight glider models to escape thermal updrafts and stay within flight time limits. The stall would bring Amber to “a near-vertical landing so it could be used from small ships, submarines or trucks/trailers,” Williams explains.

By 1988, Karem was expecting to build large numbers of the UAV for the Navy. With GPS becoming available and other key technologies gaining momentum, interest in UAVs was growing. Leading Systems now occupied 200,000 square feet of industrial space in Irvine, California, and had a contract on an airfield near El Mirage Dry Lake. In June of that year, an Amber flew over El Mirage at 5,500 feet above sea level for 38 hours. Even so, the Navy dropped a plan to buy 200, and the Army rejected the aircraft when Karem offered it as a short-range UAV, a mission in which endurance was no advantage. Around the same time, piqued by the money spent on programs like Aquila and Condor, which failed to develop useful and affordable UAVs, Congress froze funding for such programs and created a joint program office to consolidate drone development. DARPA transferred Amber to the joint program office, which promptly cancelled it.

Developing a useful and affordable UAV, however, is precisely what Karem had done. His achievement, says Bob Williams, “was not a high-aspect-ratio wing, good aerodynamics, or a lightweight structure, although good designers could do those things, and Abe could do them better than most. The issue really was reliability. Manned aircraft fly for tens of thousands of hours without crashing. So how do you even get in that ballgame? The crowning success of Amber was that by the end of the program, we were able to fly 650 hours without a loss. That was a huge order of magnitude increase in reliability [over other UAVs at the time].”

3) The Gnat-750:

When Amber’s future looked unsure, Karem shifted his focus to a lower-tech export version his team had been working on with private funding: the Gnat-750. The number refers to the chord of the wing in millimeters at its root, a dimension of the airfoil from leading to trailing edge. The Gnat was bigger, heavier, and less capable than Amber, with a two-stroke Rotax 532 engine and no canister launch capability. While Karem tried to make a foreign sale, a $5 million bank loan came due.

Alerted to the opportunity by a mutual friend, the owners of General Atomics, brothers and reputed billionaires Neal and Linden Blue, bought the assets of Leading Systems out of bankruptcy in 1990. Their company, which had been working on its own UAV with minimal success, got everything Karem had achieved with Amber and Gnat, Karem says. The Blue brothers, lifelong aviators and entrepreneurs who also saw unmanned aircraft as a beckoning frontier, hired Karem and eight of his people, getting “a team that was flying advanced UAVs like nobody else,” Karem boasts.

4) The Predator:
The CIA bought two Gnat-750s with video cameras and started flying them over Bosnia. They were launched from Albania, where their ground control station and operators were located. As that was happening, the Department of Defense held a competition for the right to demonstrate in actual missions a more advanced “medium-altitude endurance” UAV. One requirement was that the aircraft have a satellite antenna so it could be flown by operators who were much farther away than those flying the Gnat, which over Bosnia had to relay its signals to Albania through a piloted, motorized glider.
To make room for the satellite antenna, Karem gave the Gnat-750 a nose job, adding a big upward bulge. The only other major changes were a Rotax 912 engine (upgraded later to the 914), heavier landing gear, and a wing chord that measured 1,100 mm (43.25 inches) at the root. The new craft wasn’t armed, but GA-ASI’s then-president, former fighter pilot and retired rear admiral Thomas J. Cassidy, decided they should call it Predator, the name the company had used for its pre-Karem UAV.

A competition among four entrants ended with a $31.7 million contract, awarded to General Atomics in January 1994, to deliver three Predators and a ground control station within six months and more within another year. Predator crews became the first combatants in history able to spy on and, eventually, kill an enemy from the opposite side of the globe.

Karem says those who think the secret to the Predator’s success was endurance should think again. What he brought to UAVs, he says, was a refusal to treat them—as others had—like models or target drones, which aren’t built to last, and therefore aren’t built to be reliable. He designed the Albatross, Amber, Gnat-750, and Predator to fly hundreds of hours without a crash. He adds “I’m not a genius, but I am probably one of the best aircraft designers in the world today.”

BR Michael
Two pics of the Gnat-750 with the satcom radome on top.


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VTOLicious said:
He adds “I’m not a genius, but I am probably one of the best aircraft designers in the world today.”

BR Michael

This is exactly whats wrong with the aerospace industry. He may be correct, but thats not much of a boast. We are talking about people who spend hundred of millions, just to be outshined by someone in their garage.

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