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	Director, Operational Test & Evaluation
	FY98 Annual Report

SYSTEM DESCRIPTION & CONTRIBUTION TO JOINT VISION 2010

The CBU-97/B Sensor Fuzed Weapon (SFW) is a 1000 pound class, unpowered, air-delivered, wide area cluster munition designed to provide multiple kills per pass against armored and support vehicle combat formations. Fighter and bomber aircraft can employ the SFW. The primary components of the SFW are the SUU-66/B tactical munitions dispenser (TMD), 10 BLU-108/B submunitions, and 40 "hockey puck" shaped infrared sensing skeet projectiles. After release, the TMD opens and dispenses the ten submunitions, which are parachute stabilized. At a preset altitude sensed by a radar altimeter, a rocket motor fires to spin the submunition and initiate an ascent. The submunition then releases its four projectiles, which are lofted over the target area. After the projectile's sensor detects a vehicle's infrared signature, an explosively formed penetrator fires at the heat source. The SFW is currently planned to be retrofitted with the Wind Corrected Munitions Dispenser (WCMD) Tail Kit in the year 2000. The SFW BLU-108/B Submunition will also be a payload in the Joint Standoff Weapon AGM-154B (1^st LRIP Buy in FY99). SFW is certified Level 1 Y2K compliant.

The SFW program entered full-scale development in 1985. After a DAB program review, the USD(A&T) authorized LRIP in March 1992. In November 1994, USD(A&T) delegated the full-rate production decision to the Assistant Secretary of the Air Force for Acquisition. The Air Force Milestone III Acquisition Decision Memorandum was signed in June 1996.

The B-LRIP report submitted in May 1996 determined that SFW is operationally effective only when employed at low altitudes using level or shallow angle dive deliveries. Due to TMD performance limitations, the current SFW weapon configuration provides the user a limited range of tactical employment options.

The WCMD) and SFW P3I programs are intended to address current performance shortfalls in SFW. The WCMD is an inertial guidance tail kit that replaces the existing tail section of the SFW in order to improve delivery accuracy when released from medium to high altitude. The SFW with WCMD is designated as a CBU-105. The P3I program involves three major improvements: (1) improving performance against countermeasures; (2) altering the warhead design to improve performance against softer targets without degrading the current target-set performance; and (3) raising the radar altimeter height of function to increase area coverage. The current sensor will be upgraded from passive-only to a dual-mode active passive type. This will enhance the sensor's performance against cooler targets, improve weapon aimpoint, and expand the current target set.

Two Producibility Enhancement Program (PEP) hardware upgrades were initiated for SFW to reduce costs and improve producibility through design improvements. The first, PEP-1, involves electronic and mechanical changes to the projectile. The second, PEP-2, involves redesign of the sequencer and altimeter into one integrated submunition electronics unit.

The DOT&E-approved SFW TEMP consists of five future phases of OT&E testing and a new LFT&E strategy for the P3I SFW. FOT&E-1&2 will examine performance of low-rate and early full-rate production weapons that incorporate the PEP-1&2 hardware changes, respectively. The WCMD DT/IOT&E will include examination of the performance of WCMD with the SFW. The P3I DT/FOT&E will address SFW P3I performance without WCMD. FOT&E-3, scheduled for FY00-FY01, will address end-to-end performance of the CBU-105 P3I SFW. The TEMP is being updated to reflect the current approved program.

The DOT&E-approved LFT&E strategy for SFW P3I will be completed in two phases. Phase I will include: (1) collection of sensor data against a representative target set; (2) warhead performance data against armor plate targets; and (3) three test shots that repeat shotlines from the original SFW testing in 1990. An optional Phase II test will consist of a maximum of seven additional tower shots determined after the results of Phase I have been reviewed.

Three of the four FOT&E-1 missions were completed in 1998. All objectives were met during the three missions and preliminary results indicate that the PEP-1 changes have not degraded the performance of the SFW. Technical testing of the PEP-2 altimeter has identified deficiencies in performance that have necessitated an indefinite delay for FOT&E-2. The Air Force is considering combining FOT&E-2 with the SFW P3I DT/FOT&E scheduled for FY01.

Technical testing of the WCMD tail kit showed uncommanded fin movement during a supersonic release. As a result, the Air Force split the combined DT/OT and IOT&E programs into two phases. Phase I testing was intended to verify the high altitude, supersonic performance of the weapon necessary to achieve early capability on the B-52. Phase I testing was successfully completed in August 1998. Phase II testing will use production representative hardware, including the fin lock mechanism to verify all unresolved WCMD issues. Phase II combined DT/OT and IOT&E testing is planned for 2QFY99. WCMD received a favorable decision to enter LRIP following the successful completion of Phase I testing.

Technical testing of the newly designed SFW P3I active sensor has encountered performance problems, resulting in program schedule delays. In addition, the problems encountered with the PEP-2 altimeter, which is required to support P3I, have also adversely affected the SFW P3I program schedule.

Testing conducted in FY98 in support of LFT&E was limited to contractor testing of an Insensitive Munition (IM) explosive fill and testing of various design options for the multiple-fragment, explosively formed penetrator. Based on satisfactory test results, the IM fill was adopted for use in SFW P3I. Adoption of the IM explosive subsequently required a change in the manufacturing process for the P3I warhead. Unlike the liquid pouring process for Octol (the explosive fill in the baseline SFW), the IM filler (an explosive powder) requires press loading at very high pressures. Since new equipment and manufacturing techniques were required for the P3I warhead, testing was required to verify that the new process did not degrade performance of the warhead. The final series of contractor testing provided the necessary data to evaluate the new manufacturing techniques and equipment. Initial analysis shows that the process does not degrade the warhead's performance.

After a longer than expected series of dynamic and static warhead firings against rolled homogeneous armor, the final warhead design was fixed in 4QFY98. Following this testing and evaluation of the IM manufacturing process, 20 warheads were produced to support the Warhead Qualification Test. Originally scheduled for completion in FY98, Phase 1 LFT&E is delayed until 1QFY99 because of extended contractor testing. The final two phases of captive fight sensor testing have been delayed due to sensor development problems.

After determining that the first version of the LFT&E Test and Analysis Plan (TAP) needed revision, subsequent discussions between DOT&E and various Air Force LFT&E representatives resulted in agreement on the TAP's content. DOT&E will review the revised TAP prior to the beginning of Phase 1 LFT&E.

The SFW has experienced premature high altitude dispenses in both lot acceptance testing and WCMD DT. An Air Force Red Team has determined the most probable cause of failure to be the proximity fuse. The Air Force is identifying corrective actions needed to solve the problem. Analysis showed occurrence of early opening events falls within stated reliability of the FZU-39 fuse.

Overall, the SFW program continues to fall behind schedule. Further delays in PEP 2, P3I, or warhead development could threaten the planned cut-in date for P3I weapons and result in the procurement of less capable baseline weapons. Delays in the SFW P3I program also threaten to adversely impact the JSOW BLU-108 program. Preliminary testing in support of the P3I LFT&E has indicated that the newly designed multiple EFP warhead has the potential to achieve its intended effectiveness. DOT&E continues to monitor the WCMD and SFW programs due to interrelated issues.