Ramon Lopez/WASHINGTON DC

The US Navy is investigating the development of a lifting body airframe for the Boeing Stand off Land Attack Missile - Expanded Response (SLAM-ER) as an insurance policy against delays to work on a hypersonic replacement.

Capt A J Benn, USN SLAM-ER programme manager, discloses that the further improved SLAM, incorporating a wingless and finless airframe, is envisaged in the fiscal year 2007 timeframe, if other developments do not proceed to plan.

Paul Achille, Benn's deputy, says that Boeing recently completed a lifting body advanced technology demonstration (ATD) which included windtunnel testing of two-third-scale models. He says that the research is "very encouraging" and shows that a composite airframe can give the SLAM additional range and slightly better manoeuvrability.

He added that a lifting body SLAM airframe would be cheaper to build, yet strong enough to support internal missile components. Although the ATD only considered a subsonic weapon, Achille says the potential is there for a supersonic missile. Funding is being sought to keep the lifting body development effort alive.

As the USN looks into further missile developments, Boeing is heading for full rate SLAM-ER production as project officials wrap up work on the latest improvements.

The company is to upgrade the USN's inventory of 700 SLAMs. The SLAM-ER, which becomes operational in 1999, incorporates upgrades to the baseline SLAM, including planar wings for improved range, an upgraded warhead to increase penetration and software improvements.

The missile is entering its third year of production, with 75 and 60 weapons procured in fiscal years 1996 and 1997, respectively. In May, the USN enters the second low rate initial production phase.

Full rate production would begin with the planned FY1999 purchase of 54 units, followed by 58 missiles in FY2000. Funding constraints limit further annual production to 38 units through to the end of FY2011.

An automatic target acquisition unit is to be added in 1999, creating the SLAM-ER+. The earlier missiles will be retrofitted with the system, which provides autonomous guidance by matching the seeker image with a digitally stored reference photograph.

A SLAM-ER+ guidance section has been flown on a Raytheon Beech King Air, and four developmental/operational flight tests are set to begin later this year.

Source: Flight International