Narrative:

On 7/thu/05 an aircraft off of laa asked the denver center sector 27 controller for a clearance to an airport in the denver area. The controller assigned a beacon code to the aircraft; radar identified it; and issued the clearance; but forgot to activate the flight plan by entering a departure message into the computer. Consequently; the aircraft flew all the way to the denver approach boundary as a limited intruder track; while receiving no ATC services whatsoever; until the same controller descended another IFR aircraft to its altitude; causing the conflict alert to activate. The controller issued traffic to the second aircraft; still without realizing his mistake; until the second aircraft had the first one in sight. Shortly thereafter; the error was recognized; and upon investigation; the closest proximity was found to be 1.5 miles lateral and 100 ft vertical; which is very close to the resolution of the radar system. Obviously; if the WX radar quality; or controller workload had been any different; the outcome could easily have been tragic. On 5/fri/99 an aircraft cleared from gld by the denver center sector 19 controller flew well into kansas city center; below radar coverage; before the fact that the controller forgot to activate its flight plan was discovered. I filed an ASRS report on this incident. I do not have the text of that report; but I believe I made a number of suggestions as to how the process could be automated to reduce the possibility of human error. I know I made those same suggestions personally at the facility; but all were rejected because such changes could only be made at the national level. It was that response that prompted me to file an ASRS report; as I knew it was a recurring problem that would likely never be seriously addressed. In all fairness; subsequent to my report; though not as a result of my personal suggestions; the facility instituted a rule requiring controllers to start a track upon clearing an aircraft. Some controllers were already doing that; and it is a good idea; but it really doesn't solve the problem. Controllers are required to activate flight plans; but for whatever reason; they occasionally forget; and they can as easily forget to start a track. The automation suggestions I made were intended to be a barrier beyond which the controller could not proceed in the course of issuing a clearance; rather than another rule to forget. Between my first report and this most recent incident; two similar incidents have occurred; and possibly more. I don't have the dates or exact details; but one involved an aircraft that was cleared from lbf by the denver center sector 19 controller; and flew well into minneapolis center before being discovered. The aircraft had been assigned a beacon code and radar identified; but the controller forgot to activate its flight plan. The second involved an aircraft that was cleared from an airport east of gld by the denver center sector 19 controller. This incident clearly illustrates the ineffectiveness of the rule requiring controllers to start tracks when issuing a clearance; as the controller did start a track; but at the wrong airport; and without activating the flight plan. Separation was lost almost immediately after the aircraft departed; with another aircraft overflying the departure airport. The same controller who cleared the aircraft off the ground issued traffic to the overflt; using the limited intruder track; but without realizing its identity. As the track that was started on the departure was some tens of miles away at the wrong airport; and since the controller elected not to activate the flight plan; the procedure was really of no help in clearing up the confusion or of preventing the loss of separation. However; if the controller had activated the flight plan and then started a track at the wrong airport; the track and the radar target would have correlated; and made it clear much sooner what had happened. This controller; like many others; elects to not activate flight plans until the aircraft is airborne; purportedly to avoid having to update the route later. Personally; I would rather have another controller call me and ask where an airplane was; rather than be asked who an airplane was. Once again; I have personally made automation suggestions at the facility; and once again have been told that nothing can be done locally. However; a suggestion was made by a manager which might help; but it will certainly meet a great deal of resistance; as it is somewhat cumbersome. That suggestion was to cause beacon codes to timeout on proposal flight plans almost immediately after being assigned by the computer. This arrangement would require the controller to either activate the flight plan or request a code in the course of issuing a clearance; which is exactly the type of solution I have been suggesting all along. In fact; one of my suggestions was that beacon codes should not be assigned at all; until the flight plan is activated. Currently; flight plan proposals are available in the computer long before their departure times; without beacon codes. Beacon codes are assigned as the departure time approaches; and timeout several hours later. Unlike the early proposals; which have no beacon code at all; proposals with expired beacon codes retain the first two digits of the original beacon code; and have the last two digits replaced by zeros. If this suggestion were to be implemented; I would not be surprised if some controllers elected to assign the non discrete beacon code rather than activate the flight plan in order to obtain a discrete code. Here are my updated suggestions for the record: 1) prevent any computer beacon code assignments whatsoever; until a flight plan is activated. Some people will no doubt request a code using the call sign; so the computer should respond with a duplicate message; requiring the use of the cid. If a code is requested using the cid; the flight plan should be automatically activated. 2) along with beacon code assignment restrictions; starting a track should automatically activate the flight plan and assign a beacon code. If a call sign is used; the computer should respond with a duplicate message; requiring the use of the cid. 3) along with beacon code assignment restrictions; entering a departure message should automatically start a track at the departure airport and assign a beacon code. If a call sign is used; the computer should respond with a duplicate message; requiring the use of the cid. 4) limited intruder tracks should flash in the manner of conflict alert; with a similar ability to be suppressed; it is unbelievable how many limited intruder tracks fly around without being noticed; or while purposely being ignored. This is a security issue as well as a safety issue; of equal importance. There is absolutely no reason to allow an unidentified aircraft to display a discrete beacon code without intense investigation. This suggestion alone could virtually eliminate all the errors of the type mentioned in this report; with the exception of those that occurred outside radar coverage.

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Original NASA ASRS Text

Title: ZDV CTLR DESCRIBES ONGOING FAILURE TO ACTIVATE FLT PLANS RESULTING IN LIMITED AUTOMATED DATA ON IFR ACFT.

Narrative: ON 7/THU/05 AN ACFT OFF OF LAA ASKED THE DENVER CTR SECTOR 27 CTLR FOR A CLRNC TO AN ARPT IN THE DENVER AREA. THE CTLR ASSIGNED A BEACON CODE TO THE ACFT; RADAR IDENTIFIED IT; AND ISSUED THE CLRNC; BUT FORGOT TO ACTIVATE THE FLT PLAN BY ENTERING A DEP MESSAGE INTO THE COMPUTER. CONSEQUENTLY; THE ACFT FLEW ALL THE WAY TO THE DENVER APCH BOUNDARY AS A LIMITED INTRUDER TRACK; WHILE RECEIVING NO ATC SERVICES WHATSOEVER; UNTIL THE SAME CTLR DSNDED ANOTHER IFR ACFT TO ITS ALT; CAUSING THE CONFLICT ALERT TO ACTIVATE. THE CTLR ISSUED TFC TO THE SECOND ACFT; STILL WITHOUT REALIZING HIS MISTAKE; UNTIL THE SECOND ACFT HAD THE FIRST ONE IN SIGHT. SHORTLY THEREAFTER; THE ERROR WAS RECOGNIZED; AND UPON INVESTIGATION; THE CLOSEST PROXIMITY WAS FOUND TO BE 1.5 MILES LATERAL AND 100 FT VERT; WHICH IS VERY CLOSE TO THE RESOLUTION OF THE RADAR SYSTEM. OBVIOUSLY; IF THE WX RADAR QUALITY; OR CTLR WORKLOAD HAD BEEN ANY DIFFERENT; THE OUTCOME COULD EASILY HAVE BEEN TRAGIC. ON 5/FRI/99 AN ACFT CLRED FROM GLD BY THE DENVER CTR SECTOR 19 CTLR FLEW WELL INTO KANSAS CITY CTR; BELOW RADAR COVERAGE; BEFORE THE FACT THAT THE CTLR FORGOT TO ACTIVATE ITS FLT PLAN WAS DISCOVERED. I FILED AN ASRS RPT ON THIS INCIDENT. I DO NOT HAVE THE TEXT OF THAT RPT; BUT I BELIEVE I MADE A NUMBER OF SUGGESTIONS AS TO HOW THE PROCESS COULD BE AUTOMATED TO REDUCE THE POSSIBILITY OF HUMAN ERROR. I KNOW I MADE THOSE SAME SUGGESTIONS PERSONALLY AT THE FACILITY; BUT ALL WERE REJECTED BECAUSE SUCH CHANGES COULD ONLY BE MADE AT THE NATIONAL LEVEL. IT WAS THAT RESPONSE THAT PROMPTED ME TO FILE AN ASRS RPT; AS I KNEW IT WAS A RECURRING PROB THAT WOULD LIKELY NEVER BE SERIOUSLY ADDRESSED. IN ALL FAIRNESS; SUBSEQUENT TO MY RPT; THOUGH NOT AS A RESULT OF MY PERSONAL SUGGESTIONS; THE FACILITY INSTITUTED A RULE REQUIRING CTLRS TO START A TRACK UPON CLEARING AN ACFT. SOME CTLRS WERE ALREADY DOING THAT; AND IT IS A GOOD IDEA; BUT IT REALLY DOESN'T SOLVE THE PROB. CTLRS ARE REQUIRED TO ACTIVATE FLT PLANS; BUT FOR WHATEVER REASON; THEY OCCASIONALLY FORGET; AND THEY CAN AS EASILY FORGET TO START A TRACK. THE AUTOMATION SUGGESTIONS I MADE WERE INTENDED TO BE A BARRIER BEYOND WHICH THE CTLR COULD NOT PROCEED IN THE COURSE OF ISSUING A CLRNC; RATHER THAN ANOTHER RULE TO FORGET. BETWEEN MY FIRST RPT AND THIS MOST RECENT INCIDENT; TWO SIMILAR INCIDENTS HAVE OCCURRED; AND POSSIBLY MORE. I DON'T HAVE THE DATES OR EXACT DETAILS; BUT ONE INVOLVED AN ACFT THAT WAS CLRED FROM LBF BY THE DENVER CTR SECTOR 19 CTLR; AND FLEW WELL INTO MINNEAPOLIS CTR BEFORE BEING DISCOVERED. THE ACFT HAD BEEN ASSIGNED A BEACON CODE AND RADAR IDENTIFIED; BUT THE CTLR FORGOT TO ACTIVATE ITS FLT PLAN. THE SECOND INVOLVED AN ACFT THAT WAS CLEARED FROM AN ARPT E OF GLD BY THE DENVER CTR SECTOR 19 CTLR. THIS INCIDENT CLEARLY ILLUSTRATES THE INEFFECTIVENESS OF THE RULE REQUIRING CTLRS TO START TRACKS WHEN ISSUING A CLRNC; AS THE CTLR DID START A TRACK; BUT AT THE WRONG ARPT; AND WITHOUT ACTIVATING THE FLT PLAN. SEPARATION WAS LOST ALMOST IMMEDIATELY AFTER THE ACFT DEPARTED; WITH ANOTHER ACFT OVERFLYING THE DEPARTURE ARPT. THE SAME CTLR WHO CLRED THE ACFT OFF THE GND ISSUED TFC TO THE OVERFLT; USING THE LIMITED INTRUDER TRACK; BUT WITHOUT REALIZING ITS IDENTITY. AS THE TRACK THAT WAS STARTED ON THE DEP WAS SOME TENS OF MILES AWAY AT THE WRONG ARPT; AND SINCE THE CTLR ELECTED NOT TO ACTIVATE THE FLT PLAN; THE PROC WAS REALLY OF NO HELP IN CLEARING UP THE CONFUSION OR OF PREVENTING THE LOSS OF SEPARATION. HOWEVER; IF THE CTLR HAD ACTIVATED THE FLT PLAN AND THEN STARTED A TRACK AT THE WRONG ARPT; THE TRACK AND THE RADAR TARGET WOULD HAVE CORRELATED; AND MADE IT CLEAR MUCH SOONER WHAT HAD HAPPENED. THIS CTLR; LIKE MANY OTHERS; ELECTS TO NOT ACTIVATE FLT PLANS UNTIL THE ACFT IS AIRBORNE; PURPORTEDLY TO AVOID HAVING TO UPDATE THE ROUTE LATER. PERSONALLY; I WOULD RATHER HAVE ANOTHER CTLR CALL ME AND ASK WHERE AN AIRPLANE WAS; RATHER THAN BE ASKED WHO AN AIRPLANE WAS. ONCE AGAIN; I HAVE PERSONALLY MADE AUTOMATION SUGGESTIONS AT THE FACILITY; AND ONCE AGAIN HAVE BEEN TOLD THAT NOTHING CAN BE DONE LOCALLY. HOWEVER; A SUGGESTION WAS MADE BY A MANAGER WHICH MIGHT HELP; BUT IT WILL CERTAINLY MEET A GREAT DEAL OF RESISTANCE; AS IT IS SOMEWHAT CUMBERSOME. THAT SUGGESTION WAS TO CAUSE BEACON CODES TO TIMEOUT ON PROPOSAL FLT PLANS ALMOST IMMEDIATELY AFTER BEING ASSIGNED BY THE COMPUTER. THIS ARRANGEMENT WOULD REQUIRE THE CTLR TO EITHER ACTIVATE THE FLT PLAN OR REQUEST A CODE IN THE COURSE OF ISSUING A CLRNC; WHICH IS EXACTLY THE TYPE OF SOLUTION I HAVE BEEN SUGGESTING ALL ALONG. IN FACT; ONE OF MY SUGGESTIONS WAS THAT BEACON CODES SHOULD NOT BE ASSIGNED AT ALL; UNTIL THE FLT PLAN IS ACTIVATED. CURRENTLY; FLT PLAN PROPOSALS ARE AVAILABLE IN THE COMPUTER LONG BEFORE THEIR DEP TIMES; WITHOUT BEACON CODES. BEACON CODES ARE ASSIGNED AS THE DEP TIME APPROACHES; AND TIMEOUT SEVERAL HOURS LATER. UNLIKE THE EARLY PROPOSALS; WHICH HAVE NO BEACON CODE AT ALL; PROPOSALS WITH EXPIRED BEACON CODES RETAIN THE FIRST TWO DIGITS OF THE ORIGINAL BEACON CODE; AND HAVE THE LAST TWO DIGITS REPLACED BY ZEROS. IF THIS SUGGESTION WERE TO BE IMPLEMENTED; I WOULD NOT BE SURPRISED IF SOME CTLRS ELECTED TO ASSIGN THE NON DISCRETE BEACON CODE RATHER THAN ACTIVATE THE FLT PLAN IN ORDER TO OBTAIN A DISCRETE CODE. HERE ARE MY UPDATED SUGGESTIONS FOR THE RECORD: 1) PREVENT ANY COMPUTER BEACON CODE ASSIGNMENTS WHATSOEVER; UNTIL A FLT PLAN IS ACTIVATED. SOME PEOPLE WILL NO DOUBT REQUEST A CODE USING THE CALL SIGN; SO THE COMPUTER SHOULD RESPOND WITH A DUPLICATE MESSAGE; REQUIRING THE USE OF THE CID. IF A CODE IS REQUESTED USING THE CID; THE FLT PLAN SHOULD BE AUTOMATICALLY ACTIVATED. 2) ALONG WITH BEACON CODE ASSIGNMENT RESTRICTIONS; STARTING A TRACK SHOULD AUTOMATICALLY ACTIVATE THE FLT PLAN AND ASSIGN A BEACON CODE. IF A CALL SIGN IS USED; THE COMPUTER SHOULD RESPOND WITH A DUPLICATE MESSAGE; REQUIRING THE USE OF THE CID. 3) ALONG WITH BEACON CODE ASSIGNMENT RESTRICTIONS; ENTERING A DEP MESSAGE SHOULD AUTOMATICALLY START A TRACK AT THE DEP ARPT AND ASSIGN A BEACON CODE. IF A CALL SIGN IS USED; THE COMPUTER SHOULD RESPOND WITH A DUPLICATE MESSAGE; REQUIRING THE USE OF THE CID. 4) LIMITED INTRUDER TRACKS SHOULD FLASH IN THE MANNER OF CONFLICT ALERT; WITH A SIMILAR ABILITY TO BE SUPPRESSED; IT IS UNBELIEVABLE HOW MANY LIMITED INTRUDER TRACKS FLY AROUND WITHOUT BEING NOTICED; OR WHILE PURPOSELY BEING IGNORED. THIS IS A SECURITY ISSUE AS WELL AS A SAFETY ISSUE; OF EQUAL IMPORTANCE. THERE IS ABSOLUTELY NO REASON TO ALLOW AN UNIDENTIFIED ACFT TO DISPLAY A DISCRETE BEACON CODE WITHOUT INTENSE INVESTIGATION. THIS SUGGESTION ALONE COULD VIRTUALLY ELIMINATE ALL THE ERRORS OF THE TYPE MENTIONED IN THIS RPT; WITH THE EXCEPTION OF THOSE THAT OCCURRED OUTSIDE RADAR COVERAGE.

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.