WASHINGTON, Aug. 6, 2007 (PRIME NEWSWIRE) -- Northrop Grumman Corporation's (NYSE:NOC) extensive knowledge of "sense-and-avoid" (SAA) technologies that make it safer for unmanned aircraft to share airspace with piloted aircraft is an important element of the company's solution for the U.S. Navy's Broad Area Maritime Surveillance (BAMS) program.
One of the most challenging requirements for BAMS is "due regard," the ability to ensure that the unmanned aircraft can operate safely with other aircraft when outside controlled airspace not under normal flight procedures. Northrop Grumman has been working with the government on sense-and-avoid technologies for more than five years.
Northrop Grumman's BAMS offering features a maritime derivative of the proven RQ-4 Global Hawk unmanned aircraft with Navy-specific sensors and ground stations. For the BAMS due regard requirement, Northrop Grumman has proposed a low-risk, cost-effective systems solution with on-board radar as the primary sensor and additional data sources in the Mission Control System (MCS) to assist the unmanned aircraft pilot on the ground.
"The challenge is that once the unmanned aircraft has detected another aircraft as a potential collision threat, the unmanned aircraft pilot has little time to respond," said Carl Johnson, vice president and Northrop Grumman's BAMS program manager. "You need a fail-safe solution to guarantee avoidance, so we have developed algorithms to assist the pilot in choosing the right maneuver. We've found the best way is to combine the features of radar and an electro-optical sensor. This electro-optical sensor can generate visual images to provide the equivalent of human sight.
"Initially, because the radar is more mature, it will be the primary sensor for collision avoidance, but electro-optical sensors will be added to meet sense-and-avoid requirements still being developed by the Federal Aviation Administration," said Johnson.
The baseline BAMS RQ-4N solution includes a pilot-in-the-loop as the cognitive maneuver decision-maker using Northrop Grumman's initial Aircraft Collision Avoidance System (ACAS) algorithm. The ACAS software provides radar and cooperative system contact detection and tracking, which provide a recommended maneuver direction for collision avoidance while maintaining at least 500 feet of separation.
As the process is tested, matures and actions can become autonomous, a Jointly Optimal Collision Avoidance (JOCA) algorithm will be employed on the RQ-4N as it processes conflict resolution decisions. JOCA works with many competing objectives such as following right-of-way rules, keeping the contact within radar field of view and ensuring there will be no new conflict with nearby traffic to expeditiously maintain separation from potential conflicting traffic. As a result, the unmanned aircraft will be able to generate more aggressive maneuvers to avoid close-in contacts without exceeding flight limits.
"Our approach is based on many years of research, extensive government funding and Northrop Grumman's internal research and development efforts. To verify our approach, we have designed a ground laboratory for SAA hardware-in-the-loop testing and evaluation, which will be used to support our BAMS solution. The due regard solution proposed by Northrop Grumman is low risk and cost effective," concluded Johnson.
BAMS will supply the U.S. Navy with a persistent global intelligence, surveillance and reconnaissance system to protect the fleet and provide a capability to detect, track, classify, and identify maritime, littoral and land targets.
As prime contractor for the RQ-4N BAMS team, Northrop Grumman will provide the unmanned aircraft, Multi-Function Active Sensor, an active electronically scanned array radar and the Night Hunter II electro-optical infrared sensor. Other members of the team are L-3 Communications for communications integration, Raytheon for MCS segment support, and Rolls-Royce for the aircraft engine.
Northrop Grumman Corporation is a $30 billion global defense and technology company whose 120,000 employees provide innovative systems, products, and solutions in information and services, electronics, aerospace and shipbuilding to government and commercial customers worldwide.