Zephyr Net

Amraam C7, D Delayed 15 Months
Aviation Week & Space Technology
09/25/2006, page 49

Amy Butler
Eglin AFB, Fla.

Fielding of the AIM-120 C7 and D slips, but developers expect increased performance

Printed headline: New Amraams

Officials claim that the new AIM-120 variants, once fielded, will provide significant improvement over current versions. But development of the Pentagon's new advanced air-to-air missile has slipped 15 months.

Raytheon's Advanced Medium-Range Air-to-Air Missile (Amraam)--the AIM-120--has been the preeminent missile in its class and a cash cow for the company, with sales to at least 32 countries. It was introduced into the field more than a decade ago. Amraam is a beyond-visual-range weapon. Initial and mid-course guidance is provided by the launch aircraft, while Amraam's radar provides target acquisition and terminal guidance. Because airborne threats--aircraft and cruise missiles--continue to become more sophisticated and employ increasingly complicated countermeasures, the U.S. and its allies find themselves playing catch-up in a technological game of cat and mouse. Airborne targets also continue to have smaller radar cross sections.

Using round electronics cards, engineers opened up space on the Amraam C7 missile. That hole will be filled with a GPS/IMU unit in the D version, currently being developed.

In the meantime, China is developing the PL-12 active medium-range air-to-air missile. And Russia is working on technology for its R-77 (AA-12 Adder).

The Pentagon is continuing early production of the AIM-120C7 after some recent snags in operational testing. Forging ahead, the Air Force has already started to fund its follow-up, the AIM-120D. Officials here were limited in what they were willing to discuss about Amraam's ongoing development efforts.

The AIM-120C7 is estimated to cost about $700,000 per missile. It will use modern electronics on round--not longitudinal--cards in a hockey puck configuration, opening up space on the missile for upgrades to be added to the D-variant. The C7 also has a new, more robust and maintainable radar seeker, according to Lt. Col. Michael Schmidt, Amraam program manager here.

Schmidt says the Air Force "underestimated" the amount of time needed by Raytheon to build the first C7s. Operational testing was to be complete by March 2006, but additional time was needed to test software fixes for the missile. "We've encountered some things we didn't expect in operational testing, and we had to reshoot the missile," Schmidt says.

Baseline operational testing continues in parallel, but a fielding decision is not expected until the C7's Software Upgrade Program is fully tested.

Operational testing should wrap up next spring, with a fielding decision likely in June 2007. Already, more than 250 of the weapons have been produced and are in storage. The Air Force and Navy C7 buy was to be 900, but that number is going up--including 70 additional C7s this year--to compensate for the delay in the D's availability. None of the required fixes for the C7 have prompted officials to rescope work for the D variant.

Compared to the more substantial changes in the AIM-120D, the C7 is an incremental improvement. The 15-month delay in the C7 has spilled into the D developmental timeline. This summer, the Air Force added $25 million to Raytheon's AIM-120D contract to extend development to June 2008, while officials continue operational testing of some technical fixes to the C7.

The space opened up on the C7 by installing round electronic cards enables developers to install a GPS receiver on the D missile. By using GPS, the missile is directed more accurately toward its target from the moment its motor ignites. The constantly moving target--an aircraft or cruise missile--forces the missile to receive continual course corrections from the launch aircraft, or to self correct, and the GPS guidance unit allows more efficient use of the missile's propulsion.


"Because of the additional computing power and the GPS, we are better at putting the missile on the correct track from the beginning, which saves a lot of energy--it is efficiency," Schmidt says. "The increased battery life allows us to use the guidance section longer and take advantage of the missile's energy longer."

The D will be the first Amraam to have a conformal, one-way antenna on the missile's nose as well as an enhanced, two-way datalink at the back end. The improved communications capability, dubbed the "Enhanced Datalink," is designed to increase the probability of a kill, especially against advanced targets, by extending communications between the missile and launch aircraft longer than possible as compared to earlier models.

The array is wrapped around the missile, giving it a wider field of view to receive targeting updates from more angles in flight. It also eliminates the need for a launch aircraft to have a direct line of sight to the back end of the missile.

"You are kind of guessing what the missile is doing in the current environment," says Schmidt.

In other words, pilots are left to guess when they can break communications with a missile and possibly retreat to a safer position during an engagement.

"Depending on what the aircraft is doing and what the missile is doing, you get a lot better opportunity to stay in communication with the missile," Schmidt explains. Ball Aerospace is developing the conformal array.

Initial operational capability for the D is slated for the fall of 2009, and the F/A-18C/D will follow about six months later. The Air Force expects to declare operational capability for the D on the F-22 in 2013.

Meanwhile, officials at the Air Force Research Laboratory are also looking ahead to other Amraam improvements that may be ready in the near future, possibly as soon as the next decade. Among them are reaction jets, which could be used to direct the missile at extreme angles during flight, similar to thrust vectoring in a jet. Small exhaust nozzles ring the back of the missile around the main exhaust, and depending on the vector needed, these nozzles could take over, directing the missile with the heat-plume thrust. The typical Amraam fins would also be removed. Reaction jets would be useful in high-off-boresight engagements.

In other avenues, officials at Air Combat Command are now examining the potential utility of a Joint Dual Role Air Dominance Missile (JDRADM), which would be useful against short- to medium-range aerial targets as well as small ground targets. The missile, if developed, could be optimized to suppress enemy air defenses, or it could be used to work against cruise missiles. It is possible that JDRADM could assume some of the roles of the High-Speed Anti-Radiation Missile.

Eglin is finalizing negotiations for study work with three contractors, and a downselect is expected in about one year.

Defense

Production Fuzion
Aviation Week & Space Technology
09/25/2006, page 50


Amy Butler
Eglin AFB, Fla.






Air Force officials say they've stabilized production for their newest workhorse weapon fuze after supplier problems in recent years prompted the former top Air Force bomb developer to declare it "the biggest hole in the weapons world."

The service is standing up a second FMU-152 Joint Programmable Fuze (JPF) production facility at manufacturer Kaman Aerospace. The first--formerly known as Dayron, in Orlando, Fla.--was established after Motorola decided during its massive restructuring in the 1990s to abandon the fuze-making business. The second will be at Kaman's Middletown, Conn., plant. JPF will assume the roles currently handled by FMU-143 and FMU-139 fuzes.

Kaman was awarded the contract to manufacture Motorola's JPF design, but it encountered production problems. Designers found that maintainers were improperly loading early lots of the JPFs onto aircraft, prohibiting the mechanism that powers the fuze from engaging properly upon weapons release. That issue, however, has been resolved and the system now works as expected.

The workflow has since stabilized, according to Lynda Rutledge, director of fuze programs here. In Fiscal 2007, JPF production will double with the addition of a second manufacturing facility owned by Kaman, she says. Kaman acquired Dayron in 2002.

JPF is the new general purpose fuze for the Air Force and Navy. Legacy fuzes were not reprogrammable from the cockpit and required much more maintenance and attention when loading an aircraft. JPF, however, has detonation settings from instantaneous to 24 hr. It can also be adjusted from the cockpit in flight.

Developers are already looking ahead to new applications for JPF and possibly a new fuze better suited for the difficult job of detonating a penetrating weapon. Developers are planning sled tests next year of the JPF on the BLU-122, the Air Force's newest penetrator, weighing 5,000 lb.

A fuze for a penetrating weapon requires durability to survive the violent penetration into concrete and dirt and a void-counting capability--through layers of a building, for example--to detonate accurately in a specific area of the target.

Rutledge says the Air Force is exploring the outer limits of durability for the JPF in next year's tests. The goal is to explore whether modifications to it can satisfy a need for the BLU-122, or if a new fuze is necessary. "When you are putting this level of electronics and software and the kind of complexity we are talking about in something that small and having it survive this kind of impact, it is as much an engineering issue," she says. "The technology to do this is out there today." The challenge "is putting it all together in a package that can survive those kinds of impacts."

The Air Force Research Laboratory has already developed technology in these areas. The Hard Target Smart Fuze is able to withstand 8-12 kG's of force and can count layers by using an onboard accelerometer that distinguishes sand and soil from rock and concrete upon penetration. The smaller and lighter Multivent Hard-Target Fuze can handle more than twice the forces Smart Fuze can. Both would require funding for procurement if the Air Force chooses to buy them.