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Eglin wings help with B-52 weapons bay testing

(U.S. Air Force photo by Jet Fabara)

(U.S. Air Force photo by Jet Fabara)

EDWARDS AIR FORCE BASE, Calif. -- The B-52 Joint Direct Attack Munition Internal Weapons Bay Upgrade program recently completed developmental test here where it successfully demonstrated employment of JDAM munitions from the new Conventional Rotary Launcher.

Prior to this added capability, hardware and software limitations restricted the B-52's carriage of MIL-STD-1760 weapons to external pylons only. The internal weapons bay was configured either with racks, which allowed release of non-MIL-STD-1760 gravity bombs, or with a Common Strategic Rotary Launcher, which held up to eight weapons.

The CSRLs were used to carry gravity nuclear weapons, the nuclear Air-Launched Cruise Missile and the Conventional Air-Launched Cruise Missile.

These weapons operated via a MIL-STD-1553 data bus, which was incompatible with MIL-STD-1760 weapons. The IWBU program provided eight additional MIL-STD-1760 weapon stations by modifying existing CSRLs and integration of existing B-52 equipment. The modified CSRLs were designated as CRLs.

The test team consisted of many personnel linked to or headquartered at Eglin Air Force Base, Fla.  The Eglin participants were:  the 49th Test and Evaluation Squadron (a geographically separated unit of the 53rd Wing); the 53rd Test Management Group and the Air Force Seek Eagle Office.

Early on, the perceived "simplicity" of the system created discussion regarding the need or value of conducting developmental test. Fortunately, the decision was made to proceed with DT first.

During rigorous ground test efforts, hardware related deficiencies were discovered that needed to be corrected prior to the start of flight test. As an example, ground fit and function testing revealed interference issues between aircraft components and weapon arming systems. This vital issue was corrected, enabling proper functionality of the weapons after they are released from the aircraft.

Flight testing was broken into three categories: safe separation, weapon integration, and actual weapon delivery.

The first flight was a weapon release to demonstrate safe separation. Four weapons were to be released. Captive carry flights were flown to test the overall system and its ability to perform simulated weapon releases with actual weapon hardware in the loop. These tests revealed several issues, one being a dynamic software anomaly that caused the offensive avionics computer processors to shut down as the aircraft was flying towards the target. System issues discovered in DT provided insight that supported two hardware fixes and three additional software versions.

While these discovered issues drove some schedule delays, this was far less delay and cost than would have occurred had these issues been discovered during operational test or after fielding.

Although the system will continue to be improved, the JDAM IWBU flight test program ended as a success.

The B-52 IWBU program in the near future will expand the internal smart weapon carriage capability to include Joint Air-to-Surface Standoff Missiles and Miniature Air-Launched-Decoy variants.