AGM-158 JASSM

The AGM-158 JASSM (Joint Air-to-Surface Standoff Missile) is a low observable standoff cruise missile developed in the United States. It is a large, semi-stealthy long-range weapon of the 2,000 lbs class. The missile's development began in 1995, but a number of problems during testing delayed its introduction into service until 2009. The JASSM is now entering service with a number of foreign nations as well, which are Australia and Finland. An extended range version of the missile, the AGM-158B JASSM-ER (Joint Air-to-Surface Standoff Missile-Extended Range), is under development and is expected to deploy in 2013.

Origins
The JASSM project began in 1995 after the cancellation of the AGM-137 TSSAM project. The TSSAM was designed as a high precision stealthy missile for use at stand-off ranges, but poor management of the project resulted in rising costs. Since the requirement for such weapons still existed, the military quickly announced a follow-up project with similar goals. Initial contracts for two competing designs were awarded to Lockheed Martin and McDonnell Douglas in 1996, and the missile designations AGM-158A and AGM-159A were allocated to the two weapons. Lockheed Martin's AGM-158A won and a contract for further development was awarded in 1998.

The AGM-158A is powered by a Teledyne CAE J402 turbojet. Before flight the wings are kept folded to reduce size. Upon launch the wings flip out automatically. There is a single vertical tail. Guidance is via inertial navigation with updating from a global positioning system. Target recognition and terminal homing is via an imaging infrared seeker. A data link allows the missile to transmit its location and status during flight, allowing improved bomb damage assessment. Reliability has been questionable and the program has been over funded resulting in considerations to drop the program entirely. The warhead is a WDU-42/B 450 kg (1000 lb) penetrator. The JASSM will be carried by a wide range of aircraft: the F-15E, F-16, F/A-18, F/A-18E/F Super Hornet, F-35, B-1B, B-2 and B-52 are all intended to carry the weapon.

Problematic development
In 1999, powered flight tests of the missile began. These were successful, and production of the JASSM began in December 2001. The weapon began operational testing and evaluation in 2002. Late that year, two missiles failed tests and the project was delayed for three months before completing development in April 2003. Two more launches failed, this time as a result of launcher and engine problems. In July 2007, a $68 million program to improve JASSM reliability and recertify the missile was approved by the Pentagon. A decision on whether to continue with the program was deferred until Spring 2008. Lockheed agreed to fix the missiles at its own cost and has tightened up its manufacturing processes.

On 27 August 2009, David Van Buren, assistant secretary of the Air Force for acquisition, said that there would be a production gap for the JASSM while further tests were held. Further tests in 2009 were more successful however, with 15 out of 16 rounds hitting the intended target, well above the 75% benchmark set for the test. As such JASSM is now cleared for service entry. The United States Air Force plans to acquire up to 3,700 AGM-158 missiles. Meanwhile, the United States Navy had originally planned to acquire 450 AGM-158 missiles but pulled out of the program in favor of employing the proven SLAM-ER.

Foreign sales
In 2006 the Australian government announced the selection of the Lockheed Martin JASSM to equip the Royal Australian Air Force's F/A-18 Hornet fighters. This announcement came as part of a program to phase out the RAAFs F-111 strike aircraft, replacing the AGM-142 Popeye stand off missile and providing a long-range strike capability to the Hornets. JASSM was selected over the SLAM-ER since the European Taurus KEPD 350 withdraw from the tender, despite that KEPD 350 was highly rated in the earlier RFP process, due to their heavily involvement in the series preparation for the German Airforce, their troop trials in South Africa and their final negotiations with the Spanish Airforce which finally lead to a contract. As of mid-2010 the JASSM is in production for Australia and will soon enter service.

Finland had also previously planned to purchase JASSM missiles for the Finnish Air Force as part of modernization plans of its F/A-18 Hornet fleet. However in February 2007 the United States declined to sell the missiles, while agreeing to proceed as planned with other modernization efforts (the so-called Mid-Life Update 2, or MLU2). This episode led to speculation in the Finnish media on the state of Finnish - American diplomatic relations. However, in October 2011 the US DSCA announced that they had given permission for a possible sale to Finland. An order, valued 178.5 million Euros was placed in March 2012.

JASSM-Extended Range (JASSM-ER)
The US Air Force studied various improvements to the AGM-158, resulting in the development of the JASSM-Extended Range (JASSM-ER), which received the designation AGM-158B in 2002. Using a more efficient engine and larger fuel volume in an airframe with the same external dimensions as the JASSM, the JASSM-ER is intended to have a range of over 575 mi as compared to the JASSM's range of about 230 mi. Other possible improvements were studied but ultimately not pursued, including a submunition dispenser warhead, new types of homing head, and a new engine giving ranges in excess of 620 mi. The JASSM-ER has 70% hardware commonality and 95% software commonality with the original AGM-158 JASSM.

The first flight test of the JASSM-ER occurred on May 18, 2006 when a missile was launched from a U.S. Air Force B-1 bomber at the White Sands Missile Range in New Mexico. The JASSM-ER is expected to be fully operational and ready to deploy in 2013. The initial platform for the JASSM-ER will be the B-1. While both the original JASSM and the JASSM-ER are several inches too long to be carried in the internal weapons bay of the F-35 Lightning II, the F-35 will be able to carry both missiles externally, although this will compromise the aircraft's stealth features.

The JASSM-ER is also the basis for Long Range Anti-Ship Missile, which is currently a JASSM-ER with new seeker. The Air Force used the B-1 Lancer to complete a captive carry test of an LRASM to ensure the bomber can carry it, as both missiles use the same airframe. However, the LRASM will not be deployed on the B-1. Instead, the Air Force hopes to use LRASM technology, such as receiving target or coordinate updates in-flight, to add to the JASSM and give the B-1 a maritime role.

Operators

 * Royal Australian Air Force
 * Finnish Air Force
 * United States Air Force
 * Finnish Air Force
 * United States Air Force
 * United States Air Force

AGM-158A (JASSM)

 * Length: 4.27 m (14 ft)
 * Wingspan: 2.4 m (7 ft 11 in)
 * Weight: 975 kg (2,150 lb)
 * Speed: Subsonic
 * Range: 370 km (230 mi)
 * Propulsion: Teledyne CAE J402-CA-100 turbojet; thrust 3.0 kN (680 lbf)
 * Warhead: 450 kg (1000 lb) WDU-42/B penetrator
 * Production unit cost: $700,000
 * Total program cost: $3,000,000,000
 * Production dates: 1998–present

AGM-158B (JASSM-ER)

 * Speed: Subsonic
 * Range: 1000 km (620 mi)
 * Production unit cost: $1,327,000
 * Propulsion: Williams International F107-WR-105 turbofan
 * Production dates: 2010–present