An A320 on approach MMMX was told to expect the kobel 1B arrival but was never cleared to descend fr...

Narrative:

We were at FL330 approaching mexico city and the qet VOR expecting the kobek 1B arrival. We were in contact with mexico center and were told to maintain FL330 and contact mexico approach. We checked in with mexico approach at FL330 and were told by approach to maintain FL330 and expect the kobek 1B arrival. After a few minutes the captain and I began to feel like we were too high for our proximity to the airport and position on the approach. We were now inside qet and outside of kobek. We were about to query mexico approach about our altitude when mexico approach called us and asked us what our altitude was. We told them FL330 assigned. The controller responded by saying; 'negative. You should be descending to 13;000 ft. Turn to heading 090; descend to 13;000 and intercept the slm VOR 360 radial inbound to slm.' we followed these new instructions; but asked ATC to verify if we had missed a previous clearance to 13;000. It took 3 attempts to finally understand what the controller was trying to say which was that he had cleared us to descend via the kobek 1B arrival when we first checked in. Neither the captain nor I recall receiving this clearance. We intercepted the slm VOR 360 radial as instructed and resumed the arrival and ILS DME 2 for runway 23L and landed without incident. In addition to the communication barrier; the captain and I were dealing with possible windshear and moderate turbulence reports on the arrival and approach into mexico city. We are both aware of the challenges of flying into MMMX and had fully briefed many things to expect. As I write this report it is my recollection that no descent to 13;000 was given. I will take from this experience the need to be even more cognizant of potential communication miscues especially as we get closer to the airport and arrival fixes and on initial check-in with approach.

Original NASA ASRS Text

Title: An A320 on approach MMMX was told to expect the KOBEL 1B arrival but was never cleared to descend from FL330 until after QET. A descent clearance was issued off track when the Controller realized what happened.

Narrative: We were at FL330 approaching Mexico City and the QET VOR expecting the Kobek 1B arrival. We were in contact with Mexico Center and were told to maintain FL330 and contact Mexico Approach. We checked in with Mexico Approach at FL330 and were told by approach to maintain FL330 and expect the Kobek 1B arrival. After a few minutes the Captain and I began to feel like we were too high for our proximity to the airport and position on the approach. We were now inside QET and outside of Kobek. We were about to query Mexico Approach about our altitude when Mexico Approach called us and asked us what our altitude was. We told them FL330 assigned. The Controller responded by saying; 'Negative. You should be descending to 13;000 FT. Turn to heading 090; descend to 13;000 and intercept the SLM VOR 360 radial inbound to SLM.' We followed these new instructions; but asked ATC to verify if we had missed a previous clearance to 13;000. It took 3 attempts to finally understand what the Controller was trying to say which was that he had cleared us to descend via the Kobek 1B arrival when we first checked in. Neither the Captain nor I recall receiving this clearance. We intercepted the SLM VOR 360 radial as instructed and resumed the arrival and ILS DME 2 for Runway 23L and landed without incident. In addition to the communication barrier; the Captain and I were dealing with possible windshear and moderate turbulence reports on the arrival and approach into Mexico City. We are both aware of the challenges of flying into MMMX and had fully briefed many things to expect. As I write this report it is my recollection that no descent to 13;000 was given. I will take from this experience the need to be even more cognizant of potential communication miscues especially as we get closer to the airport and arrival fixes and on initial check-in with approach.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	931051
Time
Date	201102
Local Time Of Day	1201-1800
Place
Locale Reference	MMEX.ARTCC
State Reference	FO
Aircraft 1
Make Model Name	A320
Operating Under FAR Part	Part 121
Flight Phase	Cruise Descent
Route In Use	STAR KOBEK 1B
Flight Plan	IFR
Person 1
Function	First Officer Pilot Not Flying
Experience	Flight Crew Last 90 Days 150 Flight Crew Total 11000 Flight Crew Type 3000
Person 2
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 150 Flight Crew Total 17000 Flight Crew Type 4000
Events
Anomaly	ATC Issue All Types Deviation - Procedural Clearance

An A320 on approach MMMX was told to expect the kobel 1B arrival but was never cleared to descend from FL330 until after qet. A descent clearance was issued off track when the controller realized what happened.