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	Director, Operational Test & Evaluation
FY97 Annual Report

MK 48 ADCAP TORPEDO UPGRADES

	Navy ACAT III Program 1427 systems Total program cost (TY$) $183M Average unit cost (TY$) $52K Full-rate production: BU III: 4QFY97 BU IV: 4QFY00 CBASS: 4QFY04 Prime Contractor Northrup-Grumman & Raytheon Electronic Systems

SYSTEM DESCRIPTION & CONTRIBUTION TO JOINT VISION 2010

The MK 48 Mod 5 ADCAP torpedo is an improvement to the MK 48 submarine launched torpedo. It is a heavyweight acoustic homing torpedo with sophisticated sonar and a fuzed warhead. The ADCAP enhancement includes all digital guidance and control systems, digital fuzing systems, and pro-pulsion improvements which add speed, depth, and range capability. The MK 48 class torpedoes are the Navy's only submarine launched torpedoes used for engagement of submarine and surface targets, making up a significant part of the submarines' precision engagement contribution. They are essential to the force protection role of submarines. There are a number of upgrades to the ADCAP torpedo, discussed in the following paragraphs.

The Navy developed two hardware modifications to ADCAP, called the G&C (Guidance and Control) MOD and the TPU (Torpedo Propulsion Upgrade) MOD. The G&C MOD replaces the obsoles-cent guidance and control set with current technology, improves the acoustic receiver, and adds additional memory and improves processor throughput to handle the expanded software demands anticipated for near term upgrades. The TPU MOD improves the propulsion unit as discussed in the classified version of the FY96 Annual Report. Both modifications were combined into one torpedo, the MK 48 Mod 6 (MODS ADCAP). The Navy will produce about 1046 MODS ADCAPs, replacing an equivalent number of baseline (Mod 5) ADCAPs, and maintaining the total inventory of ADCAP torpedoes at 1046.

Software Block Upgrade III (BU III) is intended to provide a near-term improvement for use in the baseline G&C for improved performance in some key scenarios.

Software Block Upgrade IV is intended to provide a mid-term upgrade for use in the MODS G&C for improved performance in key scenarios as discussed in the classified version of this report. It will use advanced sonar and signal processing algorithms.

One engineering change planned for the MODS ADCAP, the Common Torpedo Development Vehicle (COT-DV), is planned for fleet introduction in the FY01 time frame. COT-DV is a common processor to be used on all advanced U.S. torpedoes, that will use COTS hardware and be significantly more capable than the current MODS G&C. It will initially use BU IV software.

Another hardware upgrade, Common Broadband Advanced Sonar System (CBASS), is planned for IOC in FY04. Additional information about CBASS is contained in the classified version of this report.

The ADCAP torpedo OPEVAL was completed in August 1988, and the B-LRIP report was sent to Congress in December 1988. ADCAP was reported to be operationally effective against certain threats, but not operationally effective against other threats at that time. The system was reported operationally suitable. The Navy subsequently authorized full-rate production, but Congress constrained procurement because of the concerns identified in test reporting. Modifications were implemented by the Navy to improve performance in certain scenarios, upgrade fuzing systems, and improve reliability. These modifications were considered effective. In 1994 a second software upgrade was introduced to improve performance and reliability. DOT&E assessed ADCAP to be operationally effective following this improvement, but some areas remained unsatisfactory. Additional detail, including areas in which DOT&E reached different conclusions than those reached by COMOPTEVFOR are discussed in the classified versions of the FY94 and FY95 Annual Reports.

The MODS ADCAP, intended to address open issues from previous OT&E, was tested in 1995 and reported in the FY95 and FY96 Annual Reports and the 1996 B-LRIP Report. U.S. ships and nuclear submarines were used as targets, simulating threat surface ships and threat nuclear and diesel submarines. A comparison with baseline ADCAP performance was done using over 400 runs in the historical data base.

DOT&E assessed MODS ADCAP to be both operationally effective and suitable. Although the reliability was marginally below threshold, DOT&E showed MODS ADCAP to produce total performance much better than the baseline ADCAP against the COEA threat. DOT&E assessed the MODS ADCAP to provide a significant advantage against nuclear submarines using some difficult evasion tactics as well, although testing was not conducted against submarines employing these tactics.

The Navy began DT of both BU III and BU IV and combined DT/OT of BU III in shallow water (DT/OT-IIIE) in 1996. This included a test involving the launch of a number of torpedoes against a representative target using an advanced evasion in a potentially adverse environment. Further details were included in the classified version of the FY96 Annual Report.

DOT&E approved the TEMP for BU III.

DOT&E participated in an IPT leading to accreditation of the Navy's hardware in the loop model, the Weapons Analysis Facility (WAF), for regression testing of BU III and BU IV ASW runs in deep water, an area which is fairly well understood.

Combined DT/OT and OPEVAL was held on BU III in 1997. Additionally, a number of BU III weapons were launched during training exercises conducted by prospective submarine commanding officers and observed by DOT&E and/or COMOPTEVFOR representatives. Testing was conducted in accordance with the approved TEMP. All test plans were approved by DOT&E, and most tests were carried out in accordance with the test plan.

Some required capabilities were not adequately tested for BU III. These are discussed in the classified version of this report. DOT&E, COMOPTEVFOR, and the Program Office have signed a memorandum of agreement to schedule and accomplish some of the needed testing.

Block Upgrade III (BU III). While COMOPTEVFOR found BU III operationally effective and suitable, DOT&E assesses BU III to be not operationally effective but operationally suitable. BU III met its operational thresholds, although it hasn't been adequately tested against all requirements yet, but did not produce improvement in some key areas. Details of the effectiveness are in the classified version of this report.

ADCAP and MODS ADCAP. The ADCAP torpedo (MK 48 Mod 5) is operationally effective in some environments, against some targets. The MODS ADCAP (MK 48 Mod 6), when properly employed, is more effective. Unfortunately, production MODS ADCAPs have shown a significant vulnerability, differing from the test units. This production problem is typical of problems seen in the initial phases of LRIP. The program office is investigating. DOT&E will continue to follow this.

Performance in some environments of both ADCAP and MODS ADCAP, against certain targets employing advanced tactics and equipment, still needs to be improved. Shortfalls are discussed in the classified version of this report. The program office is aggressively working to upgrade these modes.

Some performance questions are unresolved due to inadequate T&E support. Some testing has been done in open ocean, without range instrumentation, forcing testers to rely on the tested torpedo's internal monitoring equipment to assess torpedo performance. This has been shown to result in excessive post run analysis errors, which in at least one case led to incorrectly calling a miss a hit. Other shortcomings are discussed in the classified version of this report.

Torpedo reliability hovers around the threshold value. Reliability and availability, even if they meet thresholds, still have affected the overall effectiveness of the torpedo.

To the Navy's credit, it is concerned and aggressively addressing the performance and reliability issues. The Navy has recently resumed shooting live (non-exercise) torpedoes in carefully controlled exercises. The ADCAP program office is working hard with DOT&E and COMOPTEVFOR to resolve issues with T&E support adequacy. The program has very close ties with the operational forces. This translates directly to better support for testing and more realistic testing. It is also beneficial in that the program has direct input from the operational forces on fleet problems.

DOT&E worked with the program office to modify their incremental approach to fielding improvements that represented small enhancements. While this approach appears less expensive and is certainly less challenging and more flexible than a true block upgrade approach, it requires many more test assets to demonstrate the intended marginal improvements in multiple scenarios than the equivalent combined block upgrade would. As a result of this cooperation, the program office has combined COT-DV and BU IV development and testing.

In MODS ADCAP at-sea testing, a simple interoperability test (selecting "SNAPSHOT" fire control mode, used in quick reaction firings) demonstrated an operationally significant interoperability fault. This could have been discovered in DT, using the land-based fire control system lab.

While M&S was used in support of BU III OT&E to do deep water ASW regression testing, the V,V & A effort was not a complete success. The WAF was accredited for some parts of the run, but there were some areas of the WAF that were not faithful to in-water performance. This V,V & A effort required a number of in-water runs, so there was little cost savings in testing. Further V,V&A efforts for different torpedo improvements will also require in-water runs to validate WAF simulation of the new equipment or software, offsetting cost savings.

Notwithstanding the preceding, it is still important to validate the WAF as much as possible. Both in development and in regression testing, a number of weapons problems have been discovered and flushed out through analysis of apparent anomalous weapon behavior. The Navy's efforts to make the Weapons Analysis Facility more realistic have paid off in allowing the analysts and developers to see weapon performance that is almost exactly the same as in-water behavior in most portions of the torpedo run.

DOT&E contributed to the ADCAP Torpedo program by identifying an incorrect run analysis in open ocean testing, leading to revised test procedures. DOT&E's insistence on closer examination of the torpedo performance against selected targets and suggestions for methods to do this testing resulted in an agreement to conduct this testing in a much more representative and informative manner. Comparative evaluation with baseline torpedo performance has been sponsored by DOT&E, and is available to the community as well. COMOPTEVFOR has also been very aggressive in insisting on improvements in test realism and instrumentation as well as insisting on an adequate number of test runs.