Digital Systems Resources, (DSR Inc.)

E-2C Aircraft Display System Modernization

Ada to C++

History: The E-2C Hawkeye is a U.S. Navy all weather, carrier-based tactical aircraft. It provides airborne all-weather early warning and command-and-control functions for the carrier battle group. Additional missions include surface surveillance coordination, strike and interceptor control, search-and-rescue guidance, and communications relay. The E-2C's Mission Computer (MC) contains four Digital Equipment Corporation (DEC) 64-bit 333 MHz Alpha Model 940 Central Processing Units (CPU). The MC Operational Flight Program (OFP) is programmed in Ada. The operating system for the ACIS OFP is Unix-based and coded in C++. The Mission Computer Upgrade (MCU) is designed to receive input data from onboard and remote sensors while providing an integrated tactical picture to the CIC crew.

Challenge: The Mission Computer Fault Isolation Program (MFIP) is the central processing point for sensor data aboard the Navy's E-2C Hawkeye Airborne Early Warning aircraft. MFIP is a mission-critical real time system. The Navy contracted with Digital Systems Resources (DSR), a division of DEC, to modernize the MFIP. The MFIP was written in Ada, which required migration to C++ to support MCU platform requirements, reduce maintenance, and lower lifetime operational costs. Ada is a rich language filled with many complexities such as Variant Records, Tasking, Generic Packages, Subprograms, etc. The MCU program office identified the Ada to C++ rewrite as a high-risk project from scheduling and technical considerations. Furthermore, the transformation from Ada into C++ needed to preserve the real-time performance requirements of the E-2C Hawkeye's MFIP. The MCU program office contacted the US Office of Naval Research (USONR) to identify a viable cost effective modernization solution.

To perform the Ada to C++ transformation, TSRI first created an Ada to Intermediate Object Model (IOM) gateway within its JANUS™ automated toolset. This involved the development of a complete parser and constrainer, a task similar to the development of the initial Ada compiler. Development of the full language Ada compiler, (allowing no sub-sets), took several years for a government team of software engineers to complete.

Results: The USONR recommended The Software Revolution, Inc (TSRI), with their Automated Software Modernization (ASM) solutions, as the sole source capable of providing the MFIP modernization within schedule, performance, and cost constraints. TSRI performed a 100% automated transformation of the legacy Ada software in the MFIP and delivered a 100% error-free compile and error-free link. The deliverable was on-time, on-schedule, and within budget, meeting all contract delivery requirements. Complex integration requirements required DSR to carry out operational testing and deployment of the upgraded MFIP system without further assistance from TSRI.