By Michael Sirak
The Air Force has decided against procuring the capability to attack maritime targets with a specially configured version of the Joint Direct Attack Munition, known as the JDAM AMSTE, judging this approach to be too difficult, senior service officials said last week.
“We had pursued the JDAM AMSTE program, but found that…when we looked at this in detail, that we believed it to be too complex,” Maj. Gen. Mark Matthews, director of plans and programs for Air Combat Command, said Oct. 10, the first day of the 33rd Annual Air Armament Symposium that the Air Force and National Defense Industrial Association sponsored in Ft. Walton Beach, Fla. “So we are electing to go with a different path.”
That path, according to Matthews and the Air Force’s top weapons developers, includes relying on existing and emerging systems in the near term, like modified Sensor Fuzed Weapons (SFWs) and the Laser JDAM, a new version of the JDAM with a laser seeker for terminal guidance, to strike at-sea targets until more robust munitions emerge. Textron Systems [TXT] builds the SFW, which the company began modifying for maritime roles for the Air Force last year (Defense Daily, Aug. 11, 2006). The Laser JDAM is expected in the field around May 2008, according to briefing slides of these officials at the symposium.
In the longer term, the Air Force is planning to use a special variant of the JASSM cruise missile and the Small Diameter Bomb Increment II (SDB II) system for maritime interdiction (MI), they said.
“We believe that the JASSM MI offers great promise in this scenario,” Matthews said.
The JDAM is a Global Positioning System-guidance-aided bomb that can strike fixed-site and stationary objects in all weather conditions within several meters of the aimpoint when released from aircraft many thousands of feet in altitude above and away from the target. Boeing [BA] builds the modification kits that convert so- called dumb gravity bombs to the JDAMs.
AMSTE, which stands for Affordable Moving Surface Target Engagement, works by allowing seekerless weapons, such as the baseline JDAM, to receive GPS updates in flight from aircraft that have radars on board with a ground-moving-target-indication (GMTI) mode. Such radars are resident today on E-8C Joint Surveillance Target Attack Radar System (Joint STARS) aircraft and will be on future platforms like the F-35 Lightning II stealth fighter jet. The concept requires software modifications to the radars and the installation of antennas and a datalink on the munitions.
Northrop Grumman [NOC] matured AMSTE technologies and validated them earlier this decade against moving targets on land under a Defense Advanced Research Projects Agency-sponsored project. The Air Force took an interest in the concept since Pacific Air Forces (PACAF) had identified the need for a near-term, all-weather, precision maritime-strike capability. AMSTE also works with other seekerless glide munitions, such as the Raytheon [RTN]-built Joint Stand Off Weapon (JSOW).
In November 2004, PACAF experimented with the AMSTE capability on the 2,000-pound version of the JDAM and on the JSOW during the Resultant Fury exercise off of the coast of Hawaii (Defense Daily, Nov. 29, 2004). Based on the results of the exercise, the Air Force decided to procure the AMSTE capability for the 2,000-pound JDAM, with the goal of fielding the capability before the end of the decade (Defense Daily, Aug. 23, 2006).
But subsequently, the service realized that, while the modified JDAMs worked as intended, the demands for an airborne support infrastructure to make the concept work were too great, Judy Stokley, the Air Force’s deputy program executive officer for Weapons, told Defense Daily during an interview Oct. 10 at the symposium.
“To use a JDAM, which doesn’t have a datalink and is not powered, against a moving maritime target required an overhead architecture of surveillance and information platforms,” she said. “It took three platforms to get one JDAM on a moving target, so the warfighters decided that that was not worth investing in because that is just too hard to set up.”
Northrop Grumman spokesman Jim Stratford, said: “We still think that it is a viable technology and we are going to continue to work with the Air Force.”
The company does not believe that the AMSTE architecture is too complicated, he noted.
“Two aircraft with GMTI radar–they don’t even have to be Joint STARS,” he said.
But instead, Stokley said, the Air Force’s focus is on maturing weapons concepts that have a datalink like the JASSM MI and the SDB II because “with the datalink, you can give information directly to the weapon.”
In the interim, she said, the Air Force is procuring a limited set of Laser JDAMs. According to presentation slides by speakers at the symposium, the service is ordering 400 Laser JDAMs, while the Navy is procuring 200 of them.
“That gives some capability,” Stokley explained, “and then married with what the Navy is doing, the services decided that they could deal with that so we can get a more robust solution out there.”
The Navy, for its part, is procuring a new variant of the JSOW, designated the JSOW-C1, that will have a datalink for in-flight targeting update to strike movers at sea, Capt. Mat Winter, the Navy’s program manager for Precision Strike Weapons, said at the symposium.
The sea service is also acquiring the Harpoon Block III strike missile, which has a similar datalink and networking capabilities, and continues to refine its Standoff Land Attack Missile-Expanded Response system, he said. A recent software upgrade of the latter missile now allows it to hit moving targets traveling up to 40 miles per hour, Winter said.
Winter said the Navy is also interested in the JASSM MI. But as with the Air Force, the future of JASSM MI rests on the ability of contractor Lockheed Martin [LMT] to overcome reliability issues with the baseline configuration of the stealthy cruise missile. These issues led the Pentagon’s acquisition czar to freeze government-sponsored activities on the maritime interdiction version and associated datalink development until that time (Defense Daily, June 7).
“Assuming we get the JASSM back on course, we can get the maritime up and running again, and maybe be a little late, but still out in the field,” Maj. Gen. David Eidsaune, the Air Force’s program executive officer for Weapons, told Defense Daily Oct. 10.