When TSO 129 IFR GPS first appeared, it had onboard software called receiver autonomous integrity monitoring to keep track of the nav solution's reliability. The advent of WAAS diminished RAIM's importance, but now that many operators are using GPS as primary navigation when operating RNAV, RAIM is again important. Beginning next summer, any aircraft operating RNAV with GPS as primary nav — and many business aircraft are — will need a means of predicting RAIM availability.
As part of its popular JetPlan online flight planning system, Jeppesen has recently added a module that essentially makes RAIM prediction a menu-choice item. You plan your route, altitude and departure as usual and ask the system to calculate RAIM availability over that route. If there are gaps in the plan, the software will find them, and you can plan accordingly. The system is entirely online-based and, as Jeppesen's Mike Cetinich describes in this podcast, the calculation takes mere seconds.
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