Narrative:

Due to what I believe is a confign problem, all speed readouts on the ARTS iia here register higher than the aircraft's actual ground speed. I verified this against aircraft RNAV ground speed, DME speeds, and against the ARTCC's speed readout. While the speed varies according to which of these you ask, our speed is always higher. This causes problems with sequencing, since the speed shown on the tag never is right and you must ask the pilots their speed, causing frequency congestion, and confusion in the cockpit when I ask them to slow down to a speed greater than their current speed. This problem has been reported to the 'programming' department many times to no avail.

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Original NASA ASRS Text

Title: AIRSPD IN DATA BLOCK SHOWS HIGHER THAN THE ACFT'S ACTUAL SPD.

Narrative: DUE TO WHAT I BELIEVE IS A CONFIGN PROB, ALL SPD READOUTS ON THE ARTS IIA HERE REGISTER HIGHER THAN THE ACFT'S ACTUAL GND SPD. I VERIFIED THIS AGAINST ACFT RNAV GND SPD, DME SPDS, AND AGAINST THE ARTCC'S SPD READOUT. WHILE THE SPD VARIES ACCORDING TO WHICH OF THESE YOU ASK, OUR SPD IS ALWAYS HIGHER. THIS CAUSES PROBS WITH SEQUENCING, SINCE THE SPD SHOWN ON THE TAG NEVER IS RIGHT AND YOU MUST ASK THE PLTS THEIR SPD, CAUSING FREQ CONGESTION, AND CONFUSION IN THE COCKPIT WHEN I ASK THEM TO SLOW DOWN TO A SPD GREATER THAN THEIR CURRENT SPD. THIS PROB HAS BEEN RPTED TO THE 'PROGRAMMING' DEPT MANY TIMES TO NO AVAIL.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.