While the function and complexity of modern civil aircraft airborne software are growing rapidly, those safety standards for airborne software (such as DO-178B/C, etc.) must be satisfied at the same time. It raises more challenge to analyze and verify the consistency and integrity of airborne software requirements on the early stage of system development. This study introduces a formal modeling and analysis tool platform (avionics requirement tools, ART) for airborne software natural language requirements, and carries out a case study of the requirements of cockpit display and control software subsystem (EICAS). Firstly, the semantics of a formal variable relationship model (VRM) is given, also the platform architecture and tool chain of ART are descripted. Then, a methodology of formal analysis of requirement consistency and integrity based on multi-paradigm is given. After that, some details of the case study of EICAS are shown including: how to make a pre-modeling process of initial natural language requirements and the automatic analysis process of requirement model, such as the preprocessing and standardization of original requirement items, automatic generation of VRM models and multi-paradigm based formal analysis, etc. Finally, some experiences of this case study are drawn.