Narrative:

Descending on the avsar 3B arrival to [runway] 23L at MMMX we encountered wake turbulence from a B-747 12 miles ahead on the same arrival. We adjusted our speed and descent rate to avoid any further encounter. A few minutes later we were cleared for the ILS 23L and to caution wake turbulence behind the 747. The following controller told us to turn to a 160 heading to intercept the ILS. I told him I didn't want to cut the turn to the ILS to reduce our wake turbulence separation. He insisted that we turn at that time. We began the turn as requested but at a gradual rate to maintain a safe distance. The wind was out of the east at about 7 kts which would have maintained the wake on the glide slope. We landed uneventfully.

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Original NASA ASRS Text

Title: A B737 Captain reported encountering wake turbulence 12 miles in trail of a B747 on approach to MMMX.

Narrative: Descending on the AVSAR 3B arrival to [Runway] 23L at MMMX we encountered wake turbulence from a B-747 12 miles ahead on the same arrival. We adjusted our speed and descent rate to avoid any further encounter. A few minutes later we were cleared for the ILS 23L and to caution wake turbulence behind the 747. The following controller told us to turn to a 160 heading to intercept the ILS. I told him I didn't want to cut the turn to the ILS to reduce our wake turbulence separation. He insisted that we turn at that time. We began the turn as requested but at a gradual rate to maintain a safe distance. The wind was out of the east at about 7 kts which would have maintained the wake on the glide slope. We landed uneventfully.

Data retrieved from NASA's ASRS site 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.