RYR 350-500a/c. EZ 280-400a/c. Only 2 operators with plans for nearly 1000 a/c and none have Satcom/Acars systems because it is not mandatory. No doubt there are other similar operators worldwide who choose not to fit that equipment. That relates to 1000's of a/c, many flying in, around, over remote areas. If the basic equipment was fitted as standard and mandatory at manufacture what would it add to the cost? Peanuts I would suggest. Less than 1c per pax ticket over the lifetime of the a/c. If there was a satellite link to home base of all FDR/CVR data on a 2 hour rewrite disk then answers to WTF happened might start earlier. I'm sure they would still search for the ac/ and recover what they could of it and the pax, but the delay in finding answers would be less. Black boxes seem so low tech as the ONLY universal method. The techies will know more.