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|
Attributes | |
ACN | 429433 |
Time | |
Date | 199902 |
Day | Fri |
Local Time Of Day | 0601 To 1200 |
Place | |
Locale Reference | atc facility : zqa |
State Reference | FO |
Altitude | msl bound lower : 12300 msl bound upper : 14000 |
Environment | |
Flight Conditions | Mixed |
Light | Daylight |
Aircraft 1 | |
Operator | common carrier : air carrier |
Make Model Name | MD-80 Series (DC-9-80) Undifferentiated or Other Model |
Flight Phase | cruise other other |
Route In Use | arrival other enroute : atlantic enroute airway : br58v |
Flight Plan | IFR |
Aircraft 2 | |
Operator | common carrier : air carrier |
Make Model Name | B727 Undifferentiated or Other Model |
Flight Phase | descent other |
Route In Use | arrival other enroute : atlantic |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : flight engineer pilot : cfi |
Experience | flight time last 90 days : 100 flight time total : 20000 flight time type : 300 |
ASRS Report | 429433 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : commercial |
Events | |
Anomaly | altitude deviation : overshoot conflict : nmac non adherence : published procedure non adherence : far other anomaly other |
Independent Detector | aircraft equipment other aircraft equipment : unspecified other controllera |
Resolutory Action | flight crew : took evasive action other |
Consequence | faa : investigated faa : reviewed incident with flight crew |
Miss Distance | horizontal : 0 vertical : 100 |
Supplementary | |
Air Traffic Incident | Operational Error Pilot Deviation |
Situations | |
ATC Facility | procedure or policy : unspecified |
Navigational Aid | Unspecified |
Narrative:
We were flying flight from jfk to NAS. Flight was normal until we were approximately 50 NM northwest of NAS. At that time, ZMA (125.7) gave us a speed reduction followed by a radar vector for delay purposes. We heard the aircraft ahead of us get a holding clearance with the explanation that NAS was not accepting traffic due to heavy quantity of aircraft arriving at NAS. We were subsequently given a holding clearance at the hankx intersection. Disturbing portions to this clearance are: 1) we had been given radar vectors followed by direct to the zqa VOR so we were not on an airway leading to hankx, 2) holding clearance was not in the proper format, and 3) we were given an 'as published' holding clearance even though there were not any holding patterns depicted on the charts we were using. This last point may have been a contributing event to the near miss. In any event, we maneuvered ourselves over to the airway just as we arrived at hankx and began holding at the ZMA approved altitude of 14000 ft with left turns and 20 NM legs. During the third or fourth orbit on the outbound leg (northbound) our TCASII gave 'traffic' alerts, both aurally and visually with a yellow round DOT on the ivsi. The 'traffic' alert sounded no more than twice before it changed to 'descend' with a red square/diamond on the ivsi. I disconnected the autoplt/autothrottles and began a descent. The aural command of 'descend' continued until I considerably increased the descent rate as the green arc was now at approximately 4000 FPM. My recollection is that I attempted to shallow the descent after losing approximately 800 ft but the warning either came back on or was continuing. I can't remember which! We did not get a 'monitor vertical speed' until we were at approximately 12300 ft MSL. During this maneuver, I heard ATC in the backgnd saying 'air carrier X, climb, climb.' however, since my TCASII was giving me resolution and I could only assume that ATC may have been the one to create the problem, I elected to go with TCASII. I later found out the controller reasoning, which may have seemed logical to him at the time, but a climb would have most likely resulted in a head-to-head midair collision. During the initial part of the descent I broadcast (125.7) that flight was making a TCASII descent from 14000 ft. After the conflict was past I asked ATC what altitude they wanted us at and began a climb back to 14000 ft. We were then turned over to NAS approach to whom we announced a minimum fuel advisory. Their response was to give us a vector to the east, slow us so as to require flaps and informed us that we were #25 for the airport. I repeated our minimum fuel advisory but was made to understand that we would still be number #25 for the airport. After another 5 mins I asked for a clearance to mia and was told that mia was not accepting any traffic. I then demanded a turn to the west toward mia, advised them that I was accelerating and that I would deal with mia as I approached their airspace. We were subsequently given clearance for climb and clearance to the mia airport where we refueled and completed the original jfk-NAS mission. During the mia ground time, I complied with ZMA's request that I call them. A mr X was 1 of 2 supervisors I spoke to regarding this near miss. He stated that the investigation had already determined that the traffic, a B727, was twice given an altitude assignment of 16000 ft. The captain of the flight had already acknowledged that they indeed did bust their altitude and went through our altitude. The captain further stated that he looked up and saw our tail right in front of him at which point he pulled up and just missed hitting our tail. This agrees with our TCASII and ATC's separation of approximately 100 ft vertically. The visual picture that I have of why we continued to have and/or reacquired the 'descend' TCASII command is that the B727 was above us and descending with us until we were below 13000 ft. At that point he passed over us and was then below and behind our position. I did not see the B727 aircraft when he was in front of us. Callback conversation with reporter revealed the following information: when the flight was cleared to hankx fix for holding, the crew eventually told the controller that they were going to do a left pattern, 20 mi legs since they could not find the 'as published.' the controller replied, in a stressful voice, 'just go ahead and hold.' their aircraft did not have any other navigation equipment except VOR/DME. The crew both had their heads down looking for the holding pattern in every chart available. No TA was issued since the controller appeared to be overly stressed and burdened with traffic. It was stated to the captain, when finally arriving at nassau airport, that the traffic delay was created by the approach controller's union who had created a slow down as a political action against the minister of transport who was about to 'pull a ronald reagan.' a TA would have been helpful to the crew but the captain said the controller was barely making it with the shortest of radio contacts. The in-flight visibility was obstructed by clouds and they were basically within a set of clouds at the time. The supervisor in ZMA said that the B727 crew, with a new start-up foreign airline, had acknowledged the 16000 ft altitude assignment. The PIC felt, due to the high rate of descent of the B727, that the other crew must have missed their altitude alert at 16000 ft. The B727 was of an older model and probably did not have TCASII on board, thus no alert on their part. Since nassau is a foreign airport, the aircraft was not required to have that equipment by the FARS. As to aircraft vertical separation problems and descent rates, the PIC said that he was initially working on old, past experiences with TCASII RA's and slowly started the descent and expected the RA to cease at 300-400 ft. It wasn't until he noted the closure rate of the B727 that he realized there was a real problem of a gross overshoot coming down at a high rate. The analyst talked the pilot through the reasoning of the ZMA controller on the climb clearance. There is a 12 second 'radar sweep' delay on area radar, with the presentation of aircraft position really being '2 sweeps' behind. These 2 aircraft were closing at approximately 520 KTS which equates to 762 ft per second. The controller had information that showed the aircraft to be a false 3.5 mi further apart than what the 'real time' TCASII indicated. That is why the controller said to 'climb.' he believed the B727 was descending in front of the MD80. The ZMA supervisor stated that the controller knew he had erred in advising the MD80 to 'climb, climb' but it was high belief that the B727 was much further away than it was in actuality. The 2 aircraft passed so close that ZMA thought the 2 aircraft had hit when the radar picture showed a merger of the 2 targets. It took a rate of over 4000 FPM for the MD80 to avoid the B727 and a last moment pull-up of the B727 to avoid the tail of the MD80. Upon return to domicile the PIC felt in need of going off schedule due to trauma from the incident.
Original NASA ASRS Text
Title: AN MD80 FLC EXPERIENCES AN NMAC WHILE IN A L-HAND HOLDING PATTERN AT 14000 FT, 48 MI N OF ZQA, NASSAU, FO. AN AIRLINE B727 OVERSHOT ITS ASSIGNED ALT OF 16000 FT AND CREATED THE NMAC WHICH OCCURRED BTWN 12300 FT AND 14000 FT. LATER, ENSUING TFC DELAYS CREATED THE NEED FOR THE MD80 TO DIVERT TO MIA FOR FUEL.
Narrative: WE WERE FLYING FLT FROM JFK TO NAS. FLT WAS NORMAL UNTIL WE WERE APPROX 50 NM NW OF NAS. AT THAT TIME, ZMA (125.7) GAVE US A SPD REDUCTION FOLLOWED BY A RADAR VECTOR FOR DELAY PURPOSES. WE HEARD THE ACFT AHEAD OF US GET A HOLDING CLRNC WITH THE EXPLANATION THAT NAS WAS NOT ACCEPTING TFC DUE TO HVY QUANTITY OF ACFT ARRIVING AT NAS. WE WERE SUBSEQUENTLY GIVEN A HOLDING CLRNC AT THE HANKX INTXN. DISTURBING PORTIONS TO THIS CLRNC ARE: 1) WE HAD BEEN GIVEN RADAR VECTORS FOLLOWED BY DIRECT TO THE ZQA VOR SO WE WERE NOT ON AN AIRWAY LEADING TO HANKX, 2) HOLDING CLRNC WAS NOT IN THE PROPER FORMAT, AND 3) WE WERE GIVEN AN 'AS PUBLISHED' HOLDING CLRNC EVEN THOUGH THERE WERE NOT ANY HOLDING PATTERNS DEPICTED ON THE CHARTS WE WERE USING. THIS LAST POINT MAY HAVE BEEN A CONTRIBUTING EVENT TO THE NEAR MISS. IN ANY EVENT, WE MANEUVERED OURSELVES OVER TO THE AIRWAY JUST AS WE ARRIVED AT HANKX AND BEGAN HOLDING AT THE ZMA APPROVED ALT OF 14000 FT WITH L TURNS AND 20 NM LEGS. DURING THE THIRD OR FOURTH ORBIT ON THE OUTBOUND LEG (NBOUND) OUR TCASII GAVE 'TFC' ALERTS, BOTH AURALLY AND VISUALLY WITH A YELLOW ROUND DOT ON THE IVSI. THE 'TFC' ALERT SOUNDED NO MORE THAN TWICE BEFORE IT CHANGED TO 'DSND' WITH A RED SQUARE/DIAMOND ON THE IVSI. I DISCONNECTED THE AUTOPLT/AUTOTHROTTLES AND BEGAN A DSCNT. THE AURAL COMMAND OF 'DSND' CONTINUED UNTIL I CONSIDERABLY INCREASED THE DSCNT RATE AS THE GREEN ARC WAS NOW AT APPROX 4000 FPM. MY RECOLLECTION IS THAT I ATTEMPTED TO SHALLOW THE DSCNT AFTER LOSING APPROX 800 FT BUT THE WARNING EITHER CAME BACK ON OR WAS CONTINUING. I CAN'T REMEMBER WHICH! WE DID NOT GET A 'MONITOR VERT SPD' UNTIL WE WERE AT APPROX 12300 FT MSL. DURING THIS MANEUVER, I HEARD ATC IN THE BACKGND SAYING 'ACR X, CLB, CLB.' HOWEVER, SINCE MY TCASII WAS GIVING ME RESOLUTION AND I COULD ONLY ASSUME THAT ATC MAY HAVE BEEN THE ONE TO CREATE THE PROB, I ELECTED TO GO WITH TCASII. I LATER FOUND OUT THE CTLR REASONING, WHICH MAY HAVE SEEMED LOGICAL TO HIM AT THE TIME, BUT A CLB WOULD HAVE MOST LIKELY RESULTED IN A HEAD-TO-HEAD MIDAIR COLLISION. DURING THE INITIAL PART OF THE DSCNT I BROADCAST (125.7) THAT FLT WAS MAKING A TCASII DSCNT FROM 14000 FT. AFTER THE CONFLICT WAS PAST I ASKED ATC WHAT ALT THEY WANTED US AT AND BEGAN A CLB BACK TO 14000 FT. WE WERE THEN TURNED OVER TO NAS APCH TO WHOM WE ANNOUNCED A MINIMUM FUEL ADVISORY. THEIR RESPONSE WAS TO GIVE US A VECTOR TO THE E, SLOW US SO AS TO REQUIRE FLAPS AND INFORMED US THAT WE WERE #25 FOR THE ARPT. I REPEATED OUR MINIMUM FUEL ADVISORY BUT WAS MADE TO UNDERSTAND THAT WE WOULD STILL BE NUMBER #25 FOR THE ARPT. AFTER ANOTHER 5 MINS I ASKED FOR A CLRNC TO MIA AND WAS TOLD THAT MIA WAS NOT ACCEPTING ANY TFC. I THEN DEMANDED A TURN TO THE W TOWARD MIA, ADVISED THEM THAT I WAS ACCELERATING AND THAT I WOULD DEAL WITH MIA AS I APCHED THEIR AIRSPACE. WE WERE SUBSEQUENTLY GIVEN CLRNC FOR CLB AND CLRNC TO THE MIA ARPT WHERE WE REFUELED AND COMPLETED THE ORIGINAL JFK-NAS MISSION. DURING THE MIA GND TIME, I COMPLIED WITH ZMA'S REQUEST THAT I CALL THEM. A MR X WAS 1 OF 2 SUPVRS I SPOKE TO REGARDING THIS NEAR MISS. HE STATED THAT THE INVESTIGATION HAD ALREADY DETERMINED THAT THE TFC, A B727, WAS TWICE GIVEN AN ALT ASSIGNMENT OF 16000 FT. THE CAPT OF THE FLT HAD ALREADY ACKNOWLEDGED THAT THEY INDEED DID BUST THEIR ALT AND WENT THROUGH OUR ALT. THE CAPT FURTHER STATED THAT HE LOOKED UP AND SAW OUR TAIL RIGHT IN FRONT OF HIM AT WHICH POINT HE PULLED UP AND JUST MISSED HITTING OUR TAIL. THIS AGREES WITH OUR TCASII AND ATC'S SEPARATION OF APPROX 100 FT VERTLY. THE VISUAL PICTURE THAT I HAVE OF WHY WE CONTINUED TO HAVE AND/OR REACQUIRED THE 'DSND' TCASII COMMAND IS THAT THE B727 WAS ABOVE US AND DSNDING WITH US UNTIL WE WERE BELOW 13000 FT. AT THAT POINT HE PASSED OVER US AND WAS THEN BELOW AND BEHIND OUR POS. I DID NOT SEE THE B727 ACFT WHEN HE WAS IN FRONT OF US. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: WHEN THE FLT WAS CLRED TO HANKX FIX FOR HOLDING, THE CREW EVENTUALLY TOLD THE CTLR THAT THEY WERE GOING TO DO A L PATTERN, 20 MI LEGS SINCE THEY COULD NOT FIND THE 'AS PUBLISHED.' THE CTLR REPLIED, IN A STRESSFUL VOICE, 'JUST GO AHEAD AND HOLD.' THEIR ACFT DID NOT HAVE ANY OTHER NAV EQUIP EXCEPT VOR/DME. THE CREW BOTH HAD THEIR HEADS DOWN LOOKING FOR THE HOLDING PATTERN IN EVERY CHART AVAILABLE. NO TA WAS ISSUED SINCE THE CTLR APPEARED TO BE OVERLY STRESSED AND BURDENED WITH TFC. IT WAS STATED TO THE CAPT, WHEN FINALLY ARRIVING AT NASSAU ARPT, THAT THE TFC DELAY WAS CREATED BY THE APCH CTLR'S UNION WHO HAD CREATED A SLOW DOWN AS A POLITICAL ACTION AGAINST THE MINISTER OF TRANSPORT WHO WAS ABOUT TO 'PULL A RONALD REAGAN.' A TA WOULD HAVE BEEN HELPFUL TO THE CREW BUT THE CAPT SAID THE CTLR WAS BARELY MAKING IT WITH THE SHORTEST OF RADIO CONTACTS. THE INFLT VISIBILITY WAS OBSTRUCTED BY CLOUDS AND THEY WERE BASICALLY WITHIN A SET OF CLOUDS AT THE TIME. THE SUPVR IN ZMA SAID THAT THE B727 CREW, WITH A NEW START-UP FOREIGN AIRLINE, HAD ACKNOWLEDGED THE 16000 FT ALT ASSIGNMENT. THE PIC FELT, DUE TO THE HIGH RATE OF DSCNT OF THE B727, THAT THE OTHER CREW MUST HAVE MISSED THEIR ALT ALERT AT 16000 FT. THE B727 WAS OF AN OLDER MODEL AND PROBABLY DID NOT HAVE TCASII ON BOARD, THUS NO ALERT ON THEIR PART. SINCE NASSAU IS A FOREIGN ARPT, THE ACFT WAS NOT REQUIRED TO HAVE THAT EQUIP BY THE FARS. AS TO ACFT VERT SEPARATION PROBS AND DSCNT RATES, THE PIC SAID THAT HE WAS INITIALLY WORKING ON OLD, PAST EXPERIENCES WITH TCASII RA'S AND SLOWLY STARTED THE DSCNT AND EXPECTED THE RA TO CEASE AT 300-400 FT. IT WASN'T UNTIL HE NOTED THE CLOSURE RATE OF THE B727 THAT HE REALIZED THERE WAS A REAL PROB OF A GROSS OVERSHOOT COMING DOWN AT A HIGH RATE. THE ANALYST TALKED THE PLT THROUGH THE REASONING OF THE ZMA CTLR ON THE CLB CLRNC. THERE IS A 12 SECOND 'RADAR SWEEP' DELAY ON AREA RADAR, WITH THE PRESENTATION OF ACFT POS REALLY BEING '2 SWEEPS' BEHIND. THESE 2 ACFT WERE CLOSING AT APPROX 520 KTS WHICH EQUATES TO 762 FT PER SECOND. THE CTLR HAD INFO THAT SHOWED THE ACFT TO BE A FALSE 3.5 MI FURTHER APART THAN WHAT THE 'REAL TIME' TCASII INDICATED. THAT IS WHY THE CTLR SAID TO 'CLB.' HE BELIEVED THE B727 WAS DSNDING IN FRONT OF THE MD80. THE ZMA SUPVR STATED THAT THE CTLR KNEW HE HAD ERRED IN ADVISING THE MD80 TO 'CLB, CLB' BUT IT WAS HIGH BELIEF THAT THE B727 WAS MUCH FURTHER AWAY THAN IT WAS IN ACTUALITY. THE 2 ACFT PASSED SO CLOSE THAT ZMA THOUGHT THE 2 ACFT HAD HIT WHEN THE RADAR PICTURE SHOWED A MERGER OF THE 2 TARGETS. IT TOOK A RATE OF OVER 4000 FPM FOR THE MD80 TO AVOID THE B727 AND A LAST MOMENT PULL-UP OF THE B727 TO AVOID THE TAIL OF THE MD80. UPON RETURN TO DOMICILE THE PIC FELT IN NEED OF GOING OFF SCHEDULE DUE TO TRAUMA FROM THE INCIDENT.
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.