Electronic Warfare Countermeasures
Receiving Set (AN/ALR-20A)
Communications & Embedded Systems
Schematic of AN/ALR-20A Countermeasures Receiving Set
The AN/ALR-20A Countermeasures Receiving Set is a complex electronic warfare system installed on the B-52 G and B-52 H aircraft. It consists of 11 Line Replaceable Units (LRUs) distributed throughout the airframe. Numerous modifications and upgrades of the AN/ALR-20A prevented proper configuration control of the design. Specifications for individual LRUs had never been developed. Most documentation was either incomplete or out of date, making it difficult to establish actual system parameters. Prime contractor assistance was not possible because the original development contractor no longer existed.
The U.S. government contracted with Southwest Research Institute (SwRI) to analyze these support problems and other reliability and maintainability deficiencies and then develop recommended solutions for them. SwRI reviewed the available documentation and performed extensive electrical testing on the system. SwRI performed testing on the aircraft at various places, including:
- Air Force depot
- Intermediate shops
- SwRI
The project team assembled a complete operating AN/ALR-20A system as a hot mock-up at SwRI so that the team could perform an accurate characterization of the system interfaces.
SwRI identified a number of system problems and developed solutions, including:
- Qualification of replacement components to relieve parts shortages
- Revision of maintenance procedures to reduce failures
- Determination of component changes to overcome alignment problems
Related Terminology
obsolete technology • obsolete parts • reverse engineering • replacement engineering • FFFR • functional replacement • vanishing vendors • form, fit, and functional replacement • AN/ALR-20A Countermeasures Receiving Set • electronic warfare system • system interface characterization • replacement components • maintenance procedures • parts shortages • failure reduction
