Most glitches are localized, or there's backup systems, or you can fall back to manual human processes. If pilots/dispatchers can't get current NOTAMs, the air

Most glitches are localized, or there's backup systems, or you can fall back to manual human processes. If pilots/dispatchers can't get current NOTAMs, the aircraft can't safely depart - especially if they're flying IFR. There's no way around it. (One could argue about whether it's legal for general aviation traffic to depart VFR - the regs say you need "all available information", and the information isn't available. But that's arguing semantics.) There was a NOTAM outage about a year ago where Leidos' (the Flight Service contractor in the lower 48) computer system failed and prevented entering new notices, but as a backup they were able to call Alaska FSS on the phone. Since Alaska's FSS is still run by the federal government and used a different computer system, their system was still online. But in this case the outage is on the FAA's (upstream) side.