visitor maps

Translation-Traduction

Tuesday, June 22, 2010

First Look: Next-Gen Anti-Aircraft Missile Jammer

 

A new device, called Boldstroke, is the solution to a problem the Army does not want to have: the threat of advanced shoulder-fired missiles to American helicopters. Here are the details.

bae systems anti aircraft jammer

BAE Systems' anti-aircraft jammer system.

There's a laser-guided antiaircraft missile jammer sitting on the table of the conference room in the office of Popular Mechanics. It comes in a medium-size box, weighing in at about 30 pounds, topped with a clear hemisphere housing a prominent mirror mounted on a 360-degree gimbal. Peering inside the dome, a viewer can see a network of other mirrors that bounce light from a laser housed below, directing the beam to the main lens affixed to the gimbal. This prototype is the only one in the world, and this is the first time its inventors, BAE Systems, have brought it out of the lab for a journalist to paw over.
The device, called Boldstroke, is the solution to a problem the Army does not want to have. The threat of advanced shoulder-fired missiles to American helicopters is a nightmare, one that hearkens to the defeat of the Soviet Union in Afghanistan, where U.S. supplied Stinger missiles downed an estimated 250 Russian helicopters over two years. Shoulder-fired missiles with infrared tracking can rightfully take their place next to improvised explosive devices, sniper rifles and car bombs as gold-standard tools of asymmetric warfare.
Insurgents in Iraq have used SA-7s, shoulder-fired missiles tipped with infrared homing devices, against U.S. and British aircraft. But there are more sophisticated threats out there, like the SA-16, which has a sensitive seeker that adds ultraviolet tracking to IR seekers in order to ignore flares that aircraft fire to spoof the missiles. The SA-16 is available on the black market.
In 2008, something happened that triggered an increase in helo protection, and the Army commissioned BAE to fast-track a system that uses lasers to blind the seekers in infrared missiles. Exactly what prompted the request, called a Quick Reaction Contract, is classified. But it's not a leap to assume that intelligence reports or an actual attack set the wheels in motion. By the end of 2009 BAE delivered its first Advanced Threat Infrared Countermeasure (ATRICM) to the Army for use on its CH-47 Chinooks. ATRICM fires a pencil-thin multiband laser at frequencies that blind IR seekers scanning for targets in those same frequencies. The Pentagon recently confirmed to Aviation Week that the defensive system thwarted an IR missile attack on a Chinook, and BAE officials tell PM that the attack occurred within weeks of weeks of ATIRM's arrival in Iraq. The Army is on track to outfit its fleet of Chinooks in Iraq and Afghanistan with the protective system by the end of the year.
Helicopters are a deciding factor in both Iraq and Afghanistan—more so in Afghanistan, where roads are lacking and helos are used for resupply as well as combat missions. The crucial rotorcraft that ferries troops and supplies is the Chinook, but they depend on massive engines to haul their heavy loads. Those engines produce a lot of heat, enough to attract the attention of even modest missile seekers. “There is a huge IR signature from Chinooks,” says Ernest Keirstead, the director of BAE's Boldstroke program.
That brings us back to the prototype on the conference-room table. BAE has created Boldstroke to improve on ATIRCM. It's lighter, has fewer moving optical parts and uses mirrors instead of a physical “light pipe” to shoot its laser. Instead of three boxes, the entire unit is housed in one box. A helicopter with a Boldstroke system mounted on either side of the helicopter would have 360 degrees of protection. And the 360 gimbaled mirror is an improvement on the two-axis steering of the currently deployed ATIRCM.
The Boldstroke rollout is coinciding as simple, unguided rocket-propelled grenades (RPGs) continue to take their toll on helicopters during takeoff and landing. In early June a NATO helicopter was felled by a pair of RPGs, killing four soldiers. It is not the first such successful attack. BAE officials say they have dedicated money in-house to investigating how to modify current detection systems that could warn pilots of the approach of an RPG. The key, again, is heat from the rocket, which could be tracked by BAE's existing thermal sensors. Instead of a laser countermeasure, the system could warn pilot where the missile is coming from and allow for some evasive action.
BAE has sunk $70 million over the last three years on upgrading its lab and production infrastructure at its Nashua, N.H., facilities. They are betting—with good reason—that more work will come their way as IR missile threats proliferate. That could mean deploying similar systems on commercial airplanes as well as a wider variety of military aircraft.

No comments:

Clubic.com - Articles / Tests / Dossiers