Targeting Pod Circuit Card Shock Loading Evaluation

This task required MERC to investigate possible causes for solder joint failures on circuit card assemblies contained in an airborne targeting electronics pod. MERC produced a finite element model of the circuit card assemblies contained in the electronics pod and performed a vibration analysis.

The analysis of the CCA’s showed a potential resonance near the first harmonic of the aircraft gunfire vibration. This resonance is sensitive to the amount of support provided by the metal PCB retainers which fasten the CCA’s to the chassis. Visual evidence suggested that these retainers allowed the CCAs to deflect a substantial amount.

MERC recommended a re-design of these pieces to improve the fatigue life of the CCA’s. This re-design had minimal impact on the legacy system while improving overall system reliability.

AppliedMechanics_CCA_ModalResponse
Model of Stress on CCA Cards
Modal frequency alignment with gunfire rate decreases the life of the CCA.

Learn more about MERC’s structural analysis capabilities.