Hi:

I would like to ask you if you think if CIVA INS is worth to be installed in a short-medium hauler as B727 is. I'm flying 707 from a long year now, and the 727 more recently. Let me explain my question.

The need of an inertial system arised when crossing long distances over the water with no VOR NDB or whatever radio stations. Although LORAN stations where usefull, AFAIK signal was not allways available. So INS was usefull for the 707 (although a little unaccurate, though risky as veterans may remeber for KAL flights over USSR border).
But...Was it so usefull for a plane overflying the continent full of navaids?

Today we've got restrictions over Europe, and non RNAV certified ac can not fly above FL150, but these restrictions are quite recent (10-12 years) so If a European airline would like to upgrade a B727 Im sure they would get GPS-FMC on board (for those who like extreme ARAIG).

What do you think about this? Perhaps Lou can tell us something.