The crash of a stealthy RQ-170 Sentinel unmanned aircraft in Iran is revealing details about U.S. intelligence monitoring of that increasingly bellicose and isolated nation.

Among these clues is evidence that Washington has been conducting intelligence-gathering overflights with both stealthy and nonstealthy unmanned aircraft to observe Tehran's military developments. That a Sentinel was involved is important because the Lockheed Martin-built flying wing currently carries a full-motion video (FMV) payload (AW&ST Aug. 9, 2010, p. 29; Dec. 14, 2008, p. 26). FMV is the key to activity-based intelligence analysis, the same discipline that revealed Osama bin Laden's hiding place. Both the CIA and the National Geospatial-Intelligence Agency (NGA) see activity-based intelligence as the path to better monitoring of Iran, and they are busy expanding that capability.

Early on, officials said the crashed aircraft was possibly the Lockheed Martin Sentinel. That initial hesitation by the U.S. to confirm the downed unmanned aircraft as an RQ-170 indicates there are other aircraft monitoring Iran as well. Moreover, the intelligence community indicated that missile testing in eastern Iran was at least one of the targets of interest for Sentinel when it carried a different payload.

Yet there appears to be no panic in the military or aerospace industry about any loss of stealth or advanced intelligence, surveillance and reconnaissance (ISR) technology in the crash.

“The Iranians don't have the ability to reverse-engineer it, and there was no fancy [ISR] technology on board,” says a veteran intelligence specialist with insight into the program. “There could be a bit of a problem if the Russians or Chinese get the [airframe].”

Video released by the Iranian government shows the airframe intact, but with the landing gear and bottom of the Sentinel hidden. Specialists say the aircraft was not shot down because there is no blast or fire damage. The lack of crash damage would indicate the standard UAV flight-termination procedure after an airborne mishap of going into a flat spin. The video also shows an F-117 type grill work over the engine intake to avoid radar reflections from moving parts on the face of the engine. A Lockheed Martin stealth specialist contends that it's still an acceptable idea if the size of the aircraft is constrained and it has “big, fat, round leading edges” to further attenuate radio-frequency reflections.

Russian missile developers explained to Aviation Week the problem they had using the remains of a downed U.S. Air Force F-117 stealth fighter to upgrade the stealth-detection capability of their next-generation air defenses. Because only sections of the F-117 survived intact, “we haven't been able to model the entire [low-observable bomber],” a Russian engineer conceded. “It's not the same as testing against an undamaged F-117. You provide us with a complete stealth aircraft and then we'll tell you how effective we are.”

Having a virtually intact aircraft should present fewer problems for reverse engineering. However, it is a lengthy process and often means replicating a design that is already several years and at least a generation of technology behind.

The RQ-170, equipped with a full-motion video sensor, was a key element in the Osama bin Laden raid in Pakistan. Perhaps the most important detail that emerged from the raid was how much its planning relied on activity-based intelligence. Bin Laden was never seen, but the coming and going of important people revealed that he was there. Much of the critical information was gathered by the FMV sensor system and the data was analyzed by the National Geospatial-Intelligence Agency (NGA). The need for even more sophisticated activity-based intelligence is being emphatically touted by NGA.

“We're moving into more of an anticipatory [style of operations],” a senior agency official says. “We look at key intelligence questions and bring as many pieces of information together as we can by using multi-intelligence fusion and nontraditional sources.” The bin Laden residence was identified by “pattern of life activity, and [the NGA] worked with the assault team to look at the best way to get there,” the official says. Information developed from the data included flight path and acoustics modeling, line-of-sight analysis, landing-zone surveys and calculating the heights of walls, as well as the locations of entryways, windows and doors.

The single-channel, FMV capability is being multiplied up to 65 times in new systems being packaged for carriage by unmanned aircraft and airships. Gorgon Stare is an Air Force version of the capability. An Army system is called Argus-IS. ISR specialists contend that the UAV loss in Iran would have been far more critical if one of the multi-channel systems had fallen into Iran's possession and made its way to China or Russia, where the capability can be reverse engineered.

Gorgon Stare, developed by Sierra Nevada Corp. and the Air Force's Big Safari program, has been flying over Afghanistan on MQ-9 Reapers since December 2010. The current payload is in two pods. One carries a sensor ball produced by subcontractor ITT Defense. The ball contains five electro-optical (EO) cameras for daytime and four infrared (IR) cameras for nighttime ISR, positioned at different angles for maximum ground coverage. The pod also houses a computer processor. Images from the five EO cameras are stitched together by the computer to create an 80-megapixel image. The four IR cameras combined shoot the equivalent of two 32-megapixel frames per second. The second Gorgon Stare pod contains a computer to process and store images, a data-link modem, and two pairs of antennas for the Common Data Link and Tactical Common Data Link.

BAE Systems' multi-channel system is being automated for monitoring by fewer intelligence analysts than the current system of FMV exploitation. The wide-area persistent surveillance sensor, called the Autonomous Real-time Ground Ubiquitous Surveillance Imaging System (Argus-IS), provides that multi-channel functionality from a single sensor operating on a single platform.

The Pentagon, U.S. Army and NGA want to accelerate the use of fused data with a package that can be installed on platforms that stay aloft for days or weeks.

“That is how we are responding to the need for more access to information from the strategic to the tactical level,” says Bob Fecteau, chief information officer for BAE Systems' intelligence and security division. “With this capability comes a new challenge—how to manage the increase in the volume of data. We are awash in information. The key for analysts is to find the data when they want it, deliver it to a consumer that can make a decision based on that information and, finally, ensure the data is up to date.”

Argus-IS combines wide-area coverage (40 sq. km.) with impressive detail (15-cm.-resolution ground sample distance per pixel). Moreover, the imagery resolution allows tracking of moving vehicles and dismounted individuals.

“The way the sensor actually operates is to continuously image an area on the ground about the size of a small city, and it stores the data on board for the entire mission,” says Jeremy Tondreault, program director of the company's electronic systems business. “When an operator interacts with the system in real time, he requests the video piece so he can look for a truck, a person or a safe house. Each of the [65] video windows is analogous to what he gets today with narrow-band FMV.”

All of the data are recorded all of the time. An analyst can select any number of video windows focused anywhere around the town. He also could review what happened at the same place an hour or a day or a week before. If he missed something, he can find it. Already there are some automated functions—such as vehicle-tracking—to reduce the analysts' workload. More are under development.

“We're trying to find and characterize activity, document the critical patterns of life, discover the networks and recognize the anomalies within this group so you can find that needle in the haystack,” says Wes Green, program director of BAE Systems' global analysis business. “We're talking about a pull system where you are only extracting critical information [instead of] a push system like we currently have where each pixel is [analyzed].”

“Now we have the ability to look at a network,” he says. “So we do nodal analysis, characterize the network and create a capability to affect that network at a place and time of the Army's choosing.”

A long-term task of the Argus team is to increase the amount of the electromagnetic spectrum in which the sensor package can operate. Right now, the main imagery is EO and IR. But it could become part of a multi-intelligence-gathering system that has several sensors in a pod.