FGM-148 Javelin - Development Lessons
A key point in this era of acquisition streamlining was that it took live testing to discover the following findings, something that simulation would not have been able to accomplish.
Requirements should be formally rev7iewed periodically. Javelin requirements were written in 1988 and never updated. One requirement, the probability of kill given an engagement opportunity (PK(EO))---did not take into account selected human factors and new technology that the contractor would include in the Javelin. By the time one applied all of the contributing factors into the calculation of the PK(EO), the result was much lower than the requirement but good enough to determine the system effective given the newly understood human factors and the availability/reliability factors of system components.
DOT&E early involvement facilitates PM decisions to ensure adequate testing. Three operational tests would not have been conducted without DOT&E oversight: (1) A Limited User's Test which resulted in a number of improvements, especially in reliability and availability. (2) A Multiple Parings and Operational Lock-on Test which enabled a comparison of the entire end-to-end engagement sequence between the tactical system and the Field Tactical Trainer (FTT) that provided the appropriate insights to adequately measure how well the FTT met its requirement to replicate the tactical system. (3) A Confirmatory Test which provided performance of the Enhanced Producibility Program version of the missile early enough to impact on the MS III decision and reduce the scope of follow-on tests.
Tactics and doctrine can be developed initially by simulation but live experience was necessary to mold them into viable tactics, techniques and procedures (TTPs). One example: The ability to distinguish friend or foe becomes very difficult at greater ranges. Situational awareness and command and control measures were not adequate to preclude firing on "friendlies." The "man-in-the-loop" variable provided the insights that simulation could not yield.
Test-Fix-Test was an efficient and effective methodology that provides numerous timely changes to system design. There were several changes made to the Javelin that resulted from either Operational or Live Fire Testing. One of the more notable examples was the Power Distribution Assembly (PDA). During Phase A of the LFT, it was discovered that the main charge in the warhead in the tandem configuration was achieving about 100mm less rolled homogeneous armor penetration than had been expected. Analysis revealed that the deficiency was caused by a combination of a slightly thicker PDA bulkhead in the EPP design coupled with a second production source for the main charge liner that had used a slightly different manufacture process. The thickness of the PDA bulkhead was reduced and the expected penetration was realized.
Always anticipate updating models and simulations after live testing. LFT&E preshot predictions overstated the penetration of the Javelin warhead against targets protected by Explosive Reactive Armor. The cause was the overestimation of two aspects of tandem warhead performance. After live testing, appropriate corrections were made to input data of the penetration model before Javelin's lethality were computed.
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