Navy Turns to UAVs for Help with Radar, Communications

By Eric Beidel, Office of Naval Research

ARLINGTON, Va. (NNS) -- Scientists launched unmanned aerial vehicles (UAVs) from a research vessel July 13-18 in a significant experiment that could help boost the Navy's radar and communications performance at sea.

Sailing off Virginia Beach, Va., the Office of Naval Research's (ONR) Research Vessel (R/V) Knorr explored ocean and atmospheric weather variations that can change the angle that radar and radio waves bend, making it more difficult for ships to remain undetected and hindering their ability to communicate or locate adversaries.

Sponsored by ONR's Ocean Battlespace Sensing Department and the Oceanographer of the Navy, the initiative was part of Trident Warrior-a large annual fleet experiment organized by Navy Warfare Development Command.

Researchers used ONR-owned ScanEagle UAVs-along with unmanned undersea and surface vehicles-to obtain accurate, real-time measurements of variations in atmospheric and ocean conditions. Fluxes and turbulence caused by the interaction between the air and sea can significantly alter the path of electromagnetic waves in radar and communications systems.

Atmospheric "ducts" can trap energy in the lowest layer of the atmosphere, allowing radar and communications to travel over much longer distances, increasing the chances that information could reach unintended audiences. Energy also could be trapped aloft, preventing Navy radars from seeing things even if they normally would be well within range.

"We need to understand where we are in relation to this ducting environment and understand the energy we're emitting and the energy an adversary is emitting," said Dr. Dan Eleuterio, program officer for ONR's Ocean Battlespace Sensing Department. "If we don't know these things, it's like rolling the dice. If we do know them, it can give us a tactical advantage."

Smaller, light unmanned aircraft are ideal for the task, because they can launch from a ship, get close to the ocean's surface and fly for extended periods of time. During the experiment, the UAVs flew as close as 100 feet above the ocean's surface, allowing for more precise measurements.

Developed by the Marine Physical Laboratory at Scripps Institution of Oceanography, the sensor packages used on the ScanEagles measured everything from surface waves, winds, humidity and temperature to fluxes in mass, momentum and energy. Once collected, the data was delivered to personnel aboard a destroyer and an amphibious assault ship participating in the experiment.

"In the old days, we launched weather balloons to give us the best data on the real environment, but that only happened in one place and at one time of day," said Cmdr. Rob Witzleb, head of capabilities and requirements on the staff of the Oceanographer of the Navy. "Many miles and hours later, we were often left looking for answers when weapon systems didn't perform the way we thought they would. Using UAVs is giant leap forward in that they can give us near-continuous data, across multiple parameters where the atmosphere is the most unpredictable."

The recent research aboard R/V Knorr is in keeping with Chief of Naval Operations Adm. Jonathan Greenert's call for the Navy to expand the reach of its sensors and platforms with unmanned and autonomous systems. He has described these assets as critical for the Navy to dominate the new arenas of the electromagnetic spectrum and cyberspace.

In addition to ONR and Scripps, the experiment aboard R/V Knorr included representatives from the Naval Research Laboratory, Naval Surface Warfare Center Dahlgren, Space and Naval Warfare Systems Center Pacific, Naval Postgraduate School, Oregon State University and the Woods Hole Oceanographic Institute, which operates the research vessel, also part of the University-National Oceanographic Laboratory System.

ONR provides the science and technology necessary to maintain the Navy and Marine Corps' technological advantage. Through its affiliates, ONR is a leader in science and technology with engagement in 50 states, 70 countries, 1,035 institutions of higher learning and 914 industry partners. ONR employs approximately 1,400 people, comprising uniformed, civilian and contract personnel, with additional employees at the Naval Research Lab in Washington, D.C.

UAVs autonomously refuel in flight during DARPA demo

Two modified RQ-4 Global Hawk unmanned aerial vehicles successfully demonstrated technology that allows unmanned vehicles to be automatically refueled in-flight, an important step in conducting surveillance and combat duties, said the Defense Advanced Research Project Agency on Oct. 5.

Currently global military aviation relies on a key enabler – aerial refueling. Fighters, bombers, reconnaissance and transport aircraft use “flying gas stations” to go the extra mile, it said. Increasingly, it said UAVs are conducting combat and Intelligence, Surveillance and Reconnaissance (ISR) operations, but the aircraft aren’t designed to be refueled in flight.

DARPA said it teamed up with NASA in 2007 to show high-performance aircraft can easily perform automated refueling from conventional tankers, but many unmanned aircraft can’t match the speed, altitude and performance of the current tanker fleet. The 2007 demonstration also required a pilot on board to set conditions and monitor safety during autonomous refueling operations, it said.

On Oct 5, DARPA’s two-year Autonomous High-Altitude Refueling (AHR) program, which concluded Sep. 30, explored the ability to safely conduct fully autonomous refueling of UAVs in challenging high-altitude flight conditions. During its final test flight, two modified Global Hawk aircraft flew in close formation, 100 feet or less between refueling probe and receiver drogue, for the majority of a 2.5-hour engagement at 44,800 feet, said the agency.

The manuever demonstrated for the first time that High Altitude Long Endurance (HALE) class aircraft can safely and autonomously operate under in-flight refueling conditions, it said. The flight was the ninth test and the first time the aircraft flew close enough to measure the full aerodynamic and control interactions, it added. Flight data was analyzed over the past few months and fed back into simulations to verify system safety and performance through contact and fuel transfer–including the effects of turns and gusts up to 20 knots, it said.

According to the agency, since HALE aircraft are designed for endurance at the expense of control authority, the program started with the expectation that only one of six attempts would achieve positive contact (17 percent). The final analysis, however, showed 60 percetn of the attempts would achieve contact, it said. Multiple autonomous breakaway contingencies were successfully triggered well in advance of potentially hazardous conditions, it said. Fuel systems were also fully integrated and ground tested, demonstrating a novel “reverse-flow” approach with the tanker in trail, said DARPA, opening up valuable trade space for future developers to choose between various fixed and modular implementations of proven probe and drogue hardware.

“The goal of this demonstration was to create the expectation that future HALE aircraft will be refueled in flight,” said Jim McCormick, DARPA Program Manager. “Such designs should be more affordable to own and operate across a range of mission profiles than systems built to satisfy the most stressing case without refueling. The lessons from AHR certainly extend beyond the HALE flight regime, and insights into non-traditional tanker concepts may offer further operational advantages.”

Air Force's new surveillance system for aerial drones not working as hoped

According to a report in the Washington Post, Air Force field testers have concluded in a draft report that a new wide-area surveillance system for use with remotely piloted aircraft is "not operationally effective" and should not be fielded, but Air Force officials said Monday they expect the system will still be deployed by late winter in Afghanistan.

A Dec. 30 report by the Air Force's 53rd Wing Group at Eglin Air Force Base said that the new system, dubbed Gorgon Stare, had "significant limitations," including an inability to track people on the ground in real time, and a delay in sending real-time images to the ground.

You can read the complete article at the URL below:
http://www.washingtonpost.com/wp-dyn/content/article/2011/01/24/AR2011012406320.html?hpid=moreheadlines

U.S. was Warned of Predator Drone Hacking

Iraqi insurgents have reportedly intercepted live video feeds from the U.S. military's Predator drones using a $25.95 Windows application which allows them to track the pilotless aircraft undetected.

Hackers working with Iraqi militants were able to determine which areas of the country were under surveillance by the U.S. military, the Wall Street Journal reported on Thursday, adding that video feeds from drones in Afghanistan also appear to have been compromised.

When a Predator unmanned aerial vehicle, or UAV, is far from its base, terrain prohibits it from transmitting directly to its operator. Instead, it switches to a satellite link. That means an enterprising hacker can use his own satellite dish, a satellite modem, and a copy of the SkyGrabber Windows utility sold by the Russian company SkySoftware to intercept and display the UAV's transmissions.


Iraqi interest in intercepting U.S. military transmissions is not exactly new. A report prepared for the CIA director after the U.S. invasion and occupation noted that Saddam Hussein assigned a young relative with a master's degree in computer science to intercept transmissions from U.S. satellites. The relative, "Usama," was secretly given office space in the Baghdad Aerospace Research Center, which had access to satellite downlinks.

The 2005 CIA report compiled by special advisor Charles Duelfer quotes Abd al-Tawab Huwaysh, Saddam's minister of industry, as saying he was shown real-time overhead video supposedly of U.S. military installations in Turkey, Kuwait, and Qatar before the invasion. A likely explanation, the report concludes, is that "Usama located and downloaded the unencrypted satellite feed from U.S. military UAVs."

You can read the entire CBS News copyrighted story at click here.

Coalition Jets Shoot Down Iranian Drone Over Iraq

By Donna Miles
American Forces Press Service


WASHINGTON, March 16, 2009 - Coalition jet fighters shot down an Iranian drone that was hovering over Iraq late last month, Multinational Force Iraq officials confirmed today.
The incident occurred Feb. 25, about 60 miles northeast of Baghdad, officials said in a statement.

Two coalition aircraft were directed to visually identify the unmanned aerial vehicle after it was detected hovering inside the Iraqi border. The pilots confirmed that it wasn't a coalition aircraft and that no collateral damage would result from a shoot-down. Coalition air forces tracked the UAV for more than an hour before the pilots engaged it, officials said.

"This was not an accident on the part of the Iranians," officials said. "The UAV was in Iraqi airspace for nearly one hour and 10 minutes and well inside Iraqi territory before it was engaged."

Officials said they believe the drone to be an Iranian-made Ababil 3 model UAV.

Defense Secretary Robert M. Gates and military leaders have long accused Iran of interference in Iraq. Iran poses "a real problem," Gates said on PBS' "Tavis Smiley Show" March 11.

"I think it's one of the significant challenges that we're going to face over the next several years," he said.