Narrative:

Procedural problem causing unsafe situationuation. At dfw TRACON; triple ILS approachs are used. In paragraph 8-3b(2) of the dfw 7110.65L final controllers are to 'ensure frequency change to tower is accomplished at least 1 mi prior to the simultaneous approach fixes' then in parenthesis 'this ensures frequency change prior to loss of vertical separation.' also found 7100.65 5-9-7a2 (national order) the assumption that the pilot will actually make that frequency change 'ensuring' that it will be made prior to losing vertical separation is a false assumption. There is no way to verify the switch has been made at that point on a consistent basis; because of frequency congestion on local control frequency as well as pilot choosing flight priorities over communication to ATC. The final monitor position must be staffed during simultaneous or triple ILS approachs; 7110.65 5-9-7a6 (national). Our local order dfw 7110.65 8-4-east(2) says final monitor position 'shall monitor' localizer control frequency to 'ensure' arrival aircraft have changed to tower frequency. This sounds solid on paper but in actuality is again putting a task on a controller that he cannot effectively accomplish. If the pilot checks in on the frequency and if the local controller attempts to call the aircraft; then you can ensure the pilot switched. But if neither happens; you have ensured nothing. The only way the monitor has at present to verify and ensure the pilot switched frequencys before losing vertical is to call him on local control (tower) frequency for a radio check. This is not practical; safe or prudent to block tower's frequency with a transmission such as this; so it is not being done. Therefore; we are charged with and expected to carry out a directive we have no way to accomplish safely. Suggestion: in my experience as an arrival and final monitor controller over the last 17 yrs at dfw; I've found that few pilots actually make the switch to the tower frequency in time so as to be verified by the final monitor to comply with the aforementioned orders. I believe this can be attributed to the precarious time of flight and demands on the pilot's attention and duties to fly the approach with all the restrs given by ATC and execute the landing checklist as well as frequency congestion on the tower local control frequency. I can think of no other time in the terminal situation when a frequency change must be accomplished at a precise moment in space to determine legal separation. Given all the factors involved; the procedure 'put all the eggs in 1 basket' with no redundancy built in and certainly no room for error. Even if every pilot complied with the instruction to a 'T;' the tower frequency is simply too congested to expect each pilot to be able to check in at a precise moment in space. A viable solution would be to have the pilot use the identify feature on the transponder to show the frequency change was accomplished. This would allow the pilot to instantly indicate his presence on the frequency and he wouldn't have to wait for a chance to make his call. It would show the final monitor that the pilot was on frequency and an added benefit is that it would alleviate frequency congestion on the tower frequency. A common occurrence is that a pilot will try to check in several times before the tower will acknowledge him to issue a landing clearance. This procedure would allow the tower controller to reach out and give the landing clearance when it aligned with his control priorities. If the final monitor did not observe the identify at or prior to the simultaneous approach fix; a quick call to the arrival controller would be made to re-issue the instruction to the pilot to switch and identify. The different is that no one would assume the pilot was on frequency and just didn't have a chance to check in. It would be understood that he was not until the identify was observed.

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Original NASA ASRS Text

Title: D10 CTLR EXPRESSED CONCERN REGARDING THE MONITORING PROC DURING TRIPLE ILS APCHS THAT MAY NOT ENSURE ALT SEPARATION.

Narrative: PROCEDURAL PROB CAUSING UNSAFE SITUATIONUATION. AT DFW TRACON; TRIPLE ILS APCHS ARE USED. IN PARAGRAPH 8-3B(2) OF THE DFW 7110.65L FINAL CTLRS ARE TO 'ENSURE FREQ CHANGE TO TWR IS ACCOMPLISHED AT LEAST 1 MI PRIOR TO THE SIMULTANEOUS APCH FIXES' THEN IN PARENTHESIS 'THIS ENSURES FREQ CHANGE PRIOR TO LOSS OF VERT SEPARATION.' ALSO FOUND 7100.65 5-9-7A2 (NATIONAL ORDER) THE ASSUMPTION THAT THE PLT WILL ACTUALLY MAKE THAT FREQ CHANGE 'ENSURING' THAT IT WILL BE MADE PRIOR TO LOSING VERT SEPARATION IS A FALSE ASSUMPTION. THERE IS NO WAY TO VERIFY THE SWITCH HAS BEEN MADE AT THAT POINT ON A CONSISTENT BASIS; BECAUSE OF FREQ CONGESTION ON LCL CTL FREQ AS WELL AS PLT CHOOSING FLT PRIORITIES OVER COM TO ATC. THE FINAL MONITOR POS MUST BE STAFFED DURING SIMULTANEOUS OR TRIPLE ILS APCHS; 7110.65 5-9-7A6 (NATIONAL). OUR LCL ORDER DFW 7110.65 8-4-E(2) SAYS FINAL MONITOR POS 'SHALL MONITOR' LOC CTL FREQ TO 'ENSURE' ARR ACFT HAVE CHANGED TO TWR FREQ. THIS SOUNDS SOLID ON PAPER BUT IN ACTUALITY IS AGAIN PUTTING A TASK ON A CTLR THAT HE CANNOT EFFECTIVELY ACCOMPLISH. IF THE PLT CHKS IN ON THE FREQ AND IF THE LCL CTLR ATTEMPTS TO CALL THE ACFT; THEN YOU CAN ENSURE THE PLT SWITCHED. BUT IF NEITHER HAPPENS; YOU HAVE ENSURED NOTHING. THE ONLY WAY THE MONITOR HAS AT PRESENT TO VERIFY AND ENSURE THE PLT SWITCHED FREQS BEFORE LOSING VERT IS TO CALL HIM ON LCL CTL (TWR) FREQ FOR A RADIO CHK. THIS IS NOT PRACTICAL; SAFE OR PRUDENT TO BLOCK TWR'S FREQ WITH A XMISSION SUCH AS THIS; SO IT IS NOT BEING DONE. THEREFORE; WE ARE CHARGED WITH AND EXPECTED TO CARRY OUT A DIRECTIVE WE HAVE NO WAY TO ACCOMPLISH SAFELY. SUGGESTION: IN MY EXPERIENCE AS AN ARR AND FINAL MONITOR CTLR OVER THE LAST 17 YRS AT DFW; I'VE FOUND THAT FEW PLTS ACTUALLY MAKE THE SWITCH TO THE TWR FREQ IN TIME SO AS TO BE VERIFIED BY THE FINAL MONITOR TO COMPLY WITH THE AFOREMENTIONED ORDERS. I BELIEVE THIS CAN BE ATTRIBUTED TO THE PRECARIOUS TIME OF FLT AND DEMANDS ON THE PLT'S ATTN AND DUTIES TO FLY THE APCH WITH ALL THE RESTRS GIVEN BY ATC AND EXECUTE THE LNDG CHKLIST AS WELL AS FREQ CONGESTION ON THE TWR LCL CTL FREQ. I CAN THINK OF NO OTHER TIME IN THE TERMINAL SITUATION WHEN A FREQ CHANGE MUST BE ACCOMPLISHED AT A PRECISE MOMENT IN SPACE TO DETERMINE LEGAL SEPARATION. GIVEN ALL THE FACTORS INVOLVED; THE PROC 'PUT ALL THE EGGS IN 1 BASKET' WITH NO REDUNDANCY BUILT IN AND CERTAINLY NO ROOM FOR ERROR. EVEN IF EVERY PLT COMPLIED WITH THE INSTRUCTION TO A 'T;' THE TWR FREQ IS SIMPLY TOO CONGESTED TO EXPECT EACH PLT TO BE ABLE TO CHK IN AT A PRECISE MOMENT IN SPACE. A VIABLE SOLUTION WOULD BE TO HAVE THE PLT USE THE IDENT FEATURE ON THE XPONDER TO SHOW THE FREQ CHANGE WAS ACCOMPLISHED. THIS WOULD ALLOW THE PLT TO INSTANTLY INDICATE HIS PRESENCE ON THE FREQ AND HE WOULDN'T HAVE TO WAIT FOR A CHANCE TO MAKE HIS CALL. IT WOULD SHOW THE FINAL MONITOR THAT THE PLT WAS ON FREQ AND AN ADDED BENEFIT IS THAT IT WOULD ALLEVIATE FREQ CONGESTION ON THE TWR FREQ. A COMMON OCCURRENCE IS THAT A PLT WILL TRY TO CHK IN SEVERAL TIMES BEFORE THE TWR WILL ACKNOWLEDGE HIM TO ISSUE A LNDG CLRNC. THIS PROC WOULD ALLOW THE TWR CTLR TO REACH OUT AND GIVE THE LNDG CLRNC WHEN IT ALIGNED WITH HIS CTL PRIORITIES. IF THE FINAL MONITOR DID NOT OBSERVE THE IDENT AT OR PRIOR TO THE SIMULTANEOUS APCH FIX; A QUICK CALL TO THE ARR CTLR WOULD BE MADE TO RE-ISSUE THE INSTRUCTION TO THE PLT TO SWITCH AND IDENT. THE DIFFERENT IS THAT NO ONE WOULD ASSUME THE PLT WAS ON FREQ AND JUST DIDN'T HAVE A CHANCE TO CHK IN. IT WOULD BE UNDERSTOOD THAT HE WAS NOT UNTIL THE IDENT WAS OBSERVED.

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.