Human Interference

Simulated testing of NextGen

The problem started out like all the others.  Airplanes started coming in from every direction.  The only difference was that they were all at minimum altitude.  As the first conflict was recognized, Charlie held his breath.  The hesitation came and then sure enough, the command came out to climb the higher performance aircraft.  One after another, the conflicts were resolved and Charlie could see the guests leaning up in their seats, watching the monitors.  This was the taxpayers’ money at work.  This would look good with the voters when it reduced delays, which had become so common.

            Charlie was getting nervous now.  He started focusing on each conflict and noticed that with each one the hesitation was longer.  Would it happen during this problem?  What would the guests do?  Man!  Barney is going to go postal.  He looked over at Sean who was intently watching Charlie’s monitor.

            Looking up, Sean raised his eyebrows as if to ask, “Where’s the air show?” 

            It was Southwest Flight 765 inbound to Las Vegas and American Flight 777 departing the same airport.  Both leveled at eleven thousand feet.  At thirty miles out the commands should have been given.  It became obvious to Charlie that this was the one.  The command generator hesitated, started to give a command, and then retracted it.   Two seconds later two identical commands were sent to both aircraft. 

            As it appeared on his LCD Charlie read, “American 777, climb and maintain one-two thousand.”  Then the next command popped up. “Southwest 765 climb and maintain one-two thousand.”

            “Bingo!”  Charlie sighed leaning back in his chair.  Both aircraft climbed straight at each other with a closure rate of twelve miles a minute to twelve thousand feet.  The targets merged.  One thing Charlie did notice-- no conflict alert!  Guess they figured the computer knew there was no need to tell the controller.

            Looking around he saw Sean trying to hide his big Irish grin.  Bud was giving his engineers high fives.  Barney was just sitting there as if nothing happened.  I guess he wouldn’t know a midair if that bit him in the butt either Charlie thought to himself.  The senators just seemed to be scratching their heads.  Two minutes later another midair transpired, and Charlie keyed up his mic and terminated the test run.