With two proposals in, the U.S. Air Force’s source selection for the 250-lb. Small Diameter Bomb II (SDB II) moving-target killer is under way, and this will be the first of potentially many fixed-price competitions the Pentagon says will come for major development contracts.

Raytheon and a Boeing/Lockheed Martin submitted their proposals for the SDB II Nov. 5, and a winner is expected to be announced in May. Both contractors have been working under competing $150 million risk reduction contracts for 42 months.

To date, the Boeing/Lockheed Martin team, which is advantaged because of Boeing’s experience fielding the SDB I (a fixed-target variant), has been tight-lipped about its proposal. But company officials gave Aviation Week a peek into their plan, which Boeing Direct Attack Programs manager Dan Jaspering says is “low to moderate risk,” partly because of the company’s experience with the legacy SDB and software development that built off of that weapon as well as the highly touted Joint Direct Attack Munition (JDAM) family of weapons.

The team conducted its first flight of a “fully form-factored vehicle” in September. This included the SDB I airframe, the Lockheed Martin trimode (semi-active laser, millimeter-wave radar and imaging infrared) seeker and the two-way Harris datalink, Jaspering says. The warhead was replaced with a telemetry device needed for the flight trial.

The goal of the mission was to drop the weapon from the F-15E, acquire a fixed target and also acquire separate moving target; both targets were van-sized vehicles.

“We acquired and tracked the target and we hit the target as planned,” Jaspering says, noting the seeker also acquired the separate moving target. Prior to this demonstration, the team conducted a multi-phased approach to captive carry tests for the trimode seeker, which builds off of Lockheed Martin’s work for the Joint Common Missile/Joint Air-to-Ground Missile program, according to Debbie Rub, Boeing’s vice president for weapons. That included increasingly complex trials flown from a helicopter, KingAir and eventually the F-15E.

Rub and Jaspering declined to disclose whether the Boeing/Lockheed Martin design features a cooled seeker. The sophisticated seeker is needed to meet the requirement of destroying moving targets through bad weather or dust. Raytheon, the competition underdog, chose an uncooled seeker in an effort to reduce its proposal cost.

“Cost/price is the least important factor,” Jaspering says. “I believe [the Defense Dept. has] gone to fixed development frankly to prevent contractors from buying in. I think they are trying to get more realistic and more conservative estimates out of contractors.” The top two factors, which are equally weighted, are proposal risk and past performance. Next in importance is missile capability and finally cost.

One requirement is for the SDB II to work with the existing BRU-61 bomb rack, which can nestle four SDBs in place of a single JDAM. SDB II also is required to have the same aerodynamic and mass properties as its predecessor.

One potential area of risk for both contractors is the requirement to integrate the SDB II into the F-35 Joint Strike Fighter weapons bay; the F-35 has only just begun its test program, so some uncertainty surrounds this demand. “Certainly, there is some risk there,” Jaspering says. The companies will have to strategize to develop a reasonable cost to suit the fixed-price development contract structure, and balancing this unknown risk with a desire to be inexpensive will be a challenge.

If the Boeing/Lockheed team wins the contract, the SDB II would be manufactured at its JDAM facility in St. Charles, Mo.

The SDB II is expected to be operational first on the F-15E in 2015 and on the F-35 in 2017. Rub says Boeing could propose to move faster if the company wins. But Jaspering notes that the Pentagon is pushing for “high-confidence programs and lower risk.”

Meanwhile, Boeing and the Air Force are continuing integration work for the SDB I on the F-22. Already, the weapon is suitable for use in operations with the F-15E.

By the end of the year, Boeing plans to deliver new software that will be used to improve the SDB I’s ability to provide close air support. It was designed for long-range standoff engagement, but pilots in Afghanistan and Iraq are largely using weapons for direct attack to support ground troops.

Photo: Boeing