Narrative:

About 75-85 mi southwest of zun, ZAB issued a clearance '... Direct tonto...comply with all restrs.' normally our flts are not INS and we are routinely given the fossl 3 arrival and cross tonto at 12000 ft and 250 KTS. Since we were now proceeding INS direct to tonto and still at FL350 I asked the first officer if I was correct in understanding the last ATC clearance 'direct tonto...comply with all restrs?' he agreed that was correct. Since I was now about 65 INS mi from tonto I decided it was necessary to start our descent and left FL350. The first officer attempted to tell ATC that we were leaving FL350, but they were very busy and did not acknowledge our xmissions. I determined that a high rate of descent was necessary in order to make the expected crossing restrs at tonto. As we passed through approximately FL348 we were surprised by a pop-up TCASII TA at our 2 O'clock position, 5-6 mi and 2000 ft below us. We immediately spotted the traffic and I began to attempt to stop the descent but even after disconnecting the autoplt, I didn't get the descent reversed until we had gone through about FL344. This generated a TCASII RA (climb) which didn't cease until I had climbed back through FL347 (then 'TCASII clear of conflict'). Up to this point ATC had been busy with other traffic, but they began to query us about our altitude. We were then informed that radar showed a loss of separation and we were instructed to phone ZAB after landing at phx. We were also told that we were only expected to comply with the speed restrs at tonto and that we had not been issued a descent clearance. This event could have been catastrophic if TCASII had not alerted us to the traffic conflict. I was very upset that I had exposed my flight and the other aircraft to this dangerous situation. I take my captain's responsibilities seriously. I thought I was properly following all company and FAA policies and procedures prior to and during this event. I feel that there were several distinct factors that led me to make the decision to descend when I did: 1) we do not routinely fly INS equipped aircraft. 2) our flts to phx are routinely assigned the fossl 3 arrival and cleared to cross tonto 12000 ft at 250 KTS (or 280 KTS depending on landing direction). 3) ATC cleared us direct tonto 'comply with all restrs.' 4) we had a preconceived expectation of tonto at 12000 ft and 250 KTS. 5) our clearance to proceed INS direct to tonto put us close to tonto while still at FL350. 6) our review and crew coordination for the descent missed the word (small letters) 'expect' 12000 ft at tonto. In addition, our flight engineer was a new hire who had only recently been released to line service. He was busy getting the phx ATIS and working up a landing card while all of this was taking place. He did, however, ask me if we had been cleared to descend from FL350 just prior to the initial TCASII TA. In the future I will ask ATC for a clarification of any vague sounding clearance before starting an altitude change, and I will make a more thorough review of an expected arrival. Supplemental information from acn 357649: I was first officer on flight from st louis, mo, to phoenix, az. We were flying a L1011 at 35000 ft. Approximately 125 mi from phoenix when the captain requested to fly direct to tonto intersection, with our INS equipment. ZAB cleared us direct to tonto intersection and told us to comply with all the restrs. When I first heard this clearance I was checking the arrival chart to see if there were any other restrs on the fossl 3 arrival. Then I realized we were cleared direct to the tonto intersection and the only restrs for landing on runway 26L/right were the 250 KT restr and I noticed there was a 12000 ft restr, which when I first glanced at the restrs, I thought the 250 KTS and the 12000 ft were both restrs to be expected. As the captain approached approximately 69 mi from the tonto intersection, he started down to comply with what he apparently thought were the restrs of 250 KTS and 12000 ft at tonto, which when looking closer the restr actually was just the 250 KTS. As the captain started down I stopped reviewing the policy manual and noticed I had not dialed in a lower altitude on the altitude alerter. So I immediately called ZAB to confirm the lower altitude and my xmissions were blocked as I tired to call again the TCASII alerted us of traffic. At this point I told the captain to stop the descent, as, I recall we were at 34300 ft and the TCASII was showing 1800 ft separation. We saw the traffic visually and started to climb back to 35000 ft when the TCASII told us to climb. At this point center asked us what altitude we were at, and the captain was climbing back to 35000 ft so he told me to tell them we were at 35000 ft.

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Original NASA ASRS Text

Title: ACR X WAS CLRED DIRECT TO TONTO INTXN FOR ARR INTO PHX AND TO COMPLY WITH RESTRS. CAPT MISREAD FOSSL 3 ARR AND THOUGHT CROSS TONTO AT 12000 FT INSTEAD OF 'EXPECT' TO CROSS TONTO AT 12000 FT. ACR X RECEIVED A TCASII RA DURING DSCNT THROUGH FL343 FOR TFC AT FL330 AND STARTED A CLB BACK TO FL350, RESULTING IN LTSS.

Narrative: ABOUT 75-85 MI SW OF ZUN, ZAB ISSUED A CLRNC '... DIRECT TONTO...COMPLY WITH ALL RESTRS.' NORMALLY OUR FLTS ARE NOT INS AND WE ARE ROUTINELY GIVEN THE FOSSL 3 ARR AND CROSS TONTO AT 12000 FT AND 250 KTS. SINCE WE WERE NOW PROCEEDING INS DIRECT TO TONTO AND STILL AT FL350 I ASKED THE FO IF I WAS CORRECT IN UNDERSTANDING THE LAST ATC CLRNC 'DIRECT TONTO...COMPLY WITH ALL RESTRS?' HE AGREED THAT WAS CORRECT. SINCE I WAS NOW ABOUT 65 INS MI FROM TONTO I DECIDED IT WAS NECESSARY TO START OUR DSCNT AND LEFT FL350. THE FO ATTEMPTED TO TELL ATC THAT WE WERE LEAVING FL350, BUT THEY WERE VERY BUSY AND DID NOT ACKNOWLEDGE OUR XMISSIONS. I DETERMINED THAT A HIGH RATE OF DSCNT WAS NECESSARY IN ORDER TO MAKE THE EXPECTED XING RESTRS AT TONTO. AS WE PASSED THROUGH APPROX FL348 WE WERE SURPRISED BY A POP-UP TCASII TA AT OUR 2 O'CLOCK POS, 5-6 MI AND 2000 FT BELOW US. WE IMMEDIATELY SPOTTED THE TFC AND I BEGAN TO ATTEMPT TO STOP THE DSCNT BUT EVEN AFTER DISCONNECTING THE AUTOPLT, I DIDN'T GET THE DSCNT REVERSED UNTIL WE HAD GONE THROUGH ABOUT FL344. THIS GENERATED A TCASII RA (CLB) WHICH DIDN'T CEASE UNTIL I HAD CLBED BACK THROUGH FL347 (THEN 'TCASII CLR OF CONFLICT'). UP TO THIS POINT ATC HAD BEEN BUSY WITH OTHER TFC, BUT THEY BEGAN TO QUERY US ABOUT OUR ALT. WE WERE THEN INFORMED THAT RADAR SHOWED A LOSS OF SEPARATION AND WE WERE INSTRUCTED TO PHONE ZAB AFTER LNDG AT PHX. WE WERE ALSO TOLD THAT WE WERE ONLY EXPECTED TO COMPLY WITH THE SPD RESTRS AT TONTO AND THAT WE HAD NOT BEEN ISSUED A DSCNT CLRNC. THIS EVENT COULD HAVE BEEN CATASTROPHIC IF TCASII HAD NOT ALERTED US TO THE TFC CONFLICT. I WAS VERY UPSET THAT I HAD EXPOSED MY FLT AND THE OTHER ACFT TO THIS DANGEROUS SIT. I TAKE MY CAPT'S RESPONSIBILITIES SERIOUSLY. I THOUGHT I WAS PROPERLY FOLLOWING ALL COMPANY AND FAA POLICIES AND PROCS PRIOR TO AND DURING THIS EVENT. I FEEL THAT THERE WERE SEVERAL DISTINCT FACTORS THAT LED ME TO MAKE THE DECISION TO DSND WHEN I DID: 1) WE DO NOT ROUTINELY FLY INS EQUIPPED ACFT. 2) OUR FLTS TO PHX ARE ROUTINELY ASSIGNED THE FOSSL 3 ARR AND CLRED TO CROSS TONTO 12000 FT AT 250 KTS (OR 280 KTS DEPENDING ON LNDG DIRECTION). 3) ATC CLRED US DIRECT TONTO 'COMPLY WITH ALL RESTRS.' 4) WE HAD A PRECONCEIVED EXPECTATION OF TONTO AT 12000 FT AND 250 KTS. 5) OUR CLRNC TO PROCEED INS DIRECT TO TONTO PUT US CLOSE TO TONTO WHILE STILL AT FL350. 6) OUR REVIEW AND CREW COORD FOR THE DSCNT MISSED THE WORD (SMALL LETTERS) 'EXPECT' 12000 FT AT TONTO. IN ADDITION, OUR FE WAS A NEW HIRE WHO HAD ONLY RECENTLY BEEN RELEASED TO LINE SVC. HE WAS BUSY GETTING THE PHX ATIS AND WORKING UP A LNDG CARD WHILE ALL OF THIS WAS TAKING PLACE. HE DID, HOWEVER, ASK ME IF WE HAD BEEN CLRED TO DSND FROM FL350 JUST PRIOR TO THE INITIAL TCASII TA. IN THE FUTURE I WILL ASK ATC FOR A CLARIFICATION OF ANY VAGUE SOUNDING CLRNC BEFORE STARTING AN ALT CHANGE, AND I WILL MAKE A MORE THOROUGH REVIEW OF AN EXPECTED ARR. SUPPLEMENTAL INFO FROM ACN 357649: I WAS FO ON FLT FROM ST LOUIS, MO, TO PHOENIX, AZ. WE WERE FLYING A L1011 AT 35000 FT. APPROX 125 MI FROM PHOENIX WHEN THE CAPT REQUESTED TO FLY DIRECT TO TONTO INTXN, WITH OUR INS EQUIP. ZAB CLRED US DIRECT TO TONTO INTXN AND TOLD US TO COMPLY WITH ALL THE RESTRS. WHEN I FIRST HEARD THIS CLRNC I WAS CHKING THE ARR CHART TO SEE IF THERE WERE ANY OTHER RESTRS ON THE FOSSL 3 ARR. THEN I REALIZED WE WERE CLRED DIRECT TO THE TONTO INTXN AND THE ONLY RESTRS FOR LNDG ON RWY 26L/R WERE THE 250 KT RESTR AND I NOTICED THERE WAS A 12000 FT RESTR, WHICH WHEN I FIRST GLANCED AT THE RESTRS, I THOUGHT THE 250 KTS AND THE 12000 FT WERE BOTH RESTRS TO BE EXPECTED. AS THE CAPT APCHED APPROX 69 MI FROM THE TONTO INTXN, HE STARTED DOWN TO COMPLY WITH WHAT HE APPARENTLY THOUGHT WERE THE RESTRS OF 250 KTS AND 12000 FT AT TONTO, WHICH WHEN LOOKING CLOSER THE RESTR ACTUALLY WAS JUST THE 250 KTS. AS THE CAPT STARTED DOWN I STOPPED REVIEWING THE POLICY MANUAL AND NOTICED I HAD NOT DIALED IN A LOWER ALT ON THE ALT ALERTER. SO I IMMEDIATELY CALLED ZAB TO CONFIRM THE LOWER ALT AND MY XMISSIONS WERE BLOCKED AS I TIRED TO CALL AGAIN THE TCASII ALERTED US OF TFC. AT THIS POINT I TOLD THE CAPT TO STOP THE DSCNT, AS, I RECALL WE WERE AT 34300 FT AND THE TCASII WAS SHOWING 1800 FT SEPARATION. WE SAW THE TFC VISUALLY AND STARTED TO CLB BACK TO 35000 FT WHEN THE TCASII TOLD US TO CLB. AT THIS POINT CTR ASKED US WHAT ALT WE WERE AT, AND THE CAPT WAS CLBING BACK TO 35000 FT SO HE TOLD ME TO TELL THEM WE WERE AT 35000 FT.

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.