One has to remember the GPS / SuperTANS combination presented error codes that were “meaningless”. That is, if the system displayed a faulty the crew had no way of knowing what to do or what it meant, so would in all probability have to ignore the system or switch it off. The resultant distraction is self evident.
The GPS unit had a number of faults. Time of Day output was faulty, as was the power supply; both fairly fundamental issues in a GPS system.
Neither the GPS nor SuperTANS was cleared for use.
The SuperTANS installation was vulnerable to EMC problems.
Despite the above, MoD’s position remains that both systems were perfectly serviceable. Despite warning crews not to rely solely on the systems, MoD’s case relies solely on them.
I can’t reconcile these facts. Too many problems to be absolutely certain the system was working correctly and displaying the correct information.