Narrative:

Air carrier X was descending to the bethel (bet) terminal area for approach to bethel from the east. The aircraft is not ads-B equipped. The WX had been bad all day with many pop-up IFR requests and much IFR traffic in and out of bet. Fortunately; at the time of the incident; there was a lull in the traffic for a short period. There were several aircraft in the area that had either departed on special VFR clrncs or holding VFR for a special into the class D/east airspace. These VFR aircraft were ads-B equipped and were on the radar scope squawking 1200 via the ads-B code. Air carrier X dropped off the radar approximately 20 mi east of bet. The flight was cleared for approach. When the radar controller repositioned the data block; which was a coast track; not painted by radar or ads-B; to a spot on the radar near the airport; the data block acquired on one of the 1200 codes near the airport. The controllers reposition non-radar data blocks all the time as a technique to indicate to themselves that there is a non-radar aircraft where they are repositioning the data block to. The air carrier X data block began flying wbound from bet in the green color indicating it was ads-B equipped. This occurs with regularity in the ads-B area of ak. The FAA automation classifies the problem as a 'M-earts' problem. This does not occur in any other part of the 'M-earts' alaskan airspace that is non-ads-B. It is extremely unsafe for data blocks to have the capability of acquiring onto another aircraft. This is an unacceptable capability in all areas of air traffic control and should be unacceptable in the ads-B area of alaska.

Google
 

Original NASA ASRS Text

Title: ZAN CTLR DESCRIBED QUESTIONABLE RADAR IDENT PROCS INVOLVING ADS-B AND NON ADS-B EQUIPPED ACFT.

Narrative: ACR X WAS DSNDING TO THE BETHEL (BET) TERMINAL AREA FOR APCH TO BETHEL FROM THE E. THE ACFT IS NOT ADS-B EQUIPPED. THE WX HAD BEEN BAD ALL DAY WITH MANY POP-UP IFR REQUESTS AND MUCH IFR TFC IN AND OUT OF BET. FORTUNATELY; AT THE TIME OF THE INCIDENT; THERE WAS A LULL IN THE TFC FOR A SHORT PERIOD. THERE WERE SEVERAL ACFT IN THE AREA THAT HAD EITHER DEPARTED ON SPECIAL VFR CLRNCS OR HOLDING VFR FOR A SPECIAL INTO THE CLASS D/E AIRSPACE. THESE VFR ACFT WERE ADS-B EQUIPPED AND WERE ON THE RADAR SCOPE SQUAWKING 1200 VIA THE ADS-B CODE. ACR X DROPPED OFF THE RADAR APPROX 20 MI E OF BET. THE FLT WAS CLRED FOR APCH. WHEN THE RADAR CTLR REPOSITIONED THE DATA BLOCK; WHICH WAS A COAST TRACK; NOT PAINTED BY RADAR OR ADS-B; TO A SPOT ON THE RADAR NEAR THE ARPT; THE DATA BLOCK ACQUIRED ON ONE OF THE 1200 CODES NEAR THE ARPT. THE CTLRS REPOSITION NON-RADAR DATA BLOCKS ALL THE TIME AS A TECHNIQUE TO INDICATE TO THEMSELVES THAT THERE IS A NON-RADAR ACFT WHERE THEY ARE REPOSITIONING THE DATA BLOCK TO. THE ACR X DATA BLOCK BEGAN FLYING WBOUND FROM BET IN THE GREEN COLOR INDICATING IT WAS ADS-B EQUIPPED. THIS OCCURS WITH REGULARITY IN THE ADS-B AREA OF AK. THE FAA AUTOMATION CLASSIFIES THE PROB AS A 'M-EARTS' PROB. THIS DOES NOT OCCUR IN ANY OTHER PART OF THE 'M-EARTS' ALASKAN AIRSPACE THAT IS NON-ADS-B. IT IS EXTREMELY UNSAFE FOR DATA BLOCKS TO HAVE THE CAPABILITY OF ACQUIRING ONTO ANOTHER ACFT. THIS IS AN UNACCEPTABLE CAPABILITY IN ALL AREAS OF AIR TFC CTL AND SHOULD BE UNACCEPTABLE IN THE ADS-B AREA OF ALASKA.

Data retrieved from NASA's ASRS site as of January 2009 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.