Narrative:

During preflight planning we uploaded and reviewed the plan for this flight. Weather for departure; enroute; and arrival phases of flight were relatively benign; although metars indicated trending marginal VFR conditions with ceilings of 20 tcu (towering cumulus); and taf for arrival indicating VFR with PROB40 for light rain. Nearby had a tempo for thunderstorms. Dispatcher remarks further indicated no arrival delays. The dispatcher planned [remaining] fuel of 1:01/4900lbs. Fuel load was legal but I felt surprised that more extra fuel [had not] been planned relative to the operational contingencies that can easily occur in the MMMX operation even under a situation with no delays. The flight was to be flown at night to an airport that has a challenging approach procedure; along with high terrain in most quadrants. Having flown this route segment many times; I am fairly aware of the procedures and challenges to this operation. Often on approach; ATC will give headings off the STAR to intercept radials inbound to the IAF to accommodate spacing with other aircraft. I have seen this happen very spontaneously even if the airport is not busy. The approach procedure (ILS-2 05R) is rather challenging; but not insurmountable to an experienced crew. If a go around were to be executed; the map is not an easy boxed pattern back to the field. It would most likely require vectors well to the north and back onto the long approach path required to this runway due to terrain. Runways at MMMX are non-grooved; and pose operational challenges when wet. If an incident occurred with an inbound airplane; it could cause unforeseen delays. The MMMX briefing guide from the airbus fleet spells out numerous other contingencies that can occur flying to this airport. I called the dispatcher to discuss the planning of this flight; and shared my thoughts about the fuel load. He asked me how much fuel I wanted; and he gave me my request without incident. I added ZZZ1 as a precautionary alternate relative to the trends on the current metars and nearby taf. The flight operated uneventfully.

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Original NASA ASRS Text

Title: A319 Captain reported concern with the fuel planned for the flight to MMMX and requested an increase.

Narrative: During preflight planning we uploaded and reviewed the plan for this flight. Weather for departure; enroute; and arrival phases of flight were relatively benign; although METARS indicated trending marginal VFR conditions with ceilings of 20 TCU (Towering Cumulus); and TAF for arrival indicating VFR with PROB40 for light rain. Nearby had a TEMPO for thunderstorms. Dispatcher remarks further indicated no arrival delays. The Dispatcher planned [remaining] fuel of 1:01/4900lbs. Fuel load was legal but I felt surprised that more extra fuel [had not] been planned relative to the operational contingencies that can easily occur in the MMMX operation even under a situation with no delays. The flight was to be flown at night to an airport that has a challenging approach procedure; along with high terrain in most quadrants. Having flown this route segment many times; I am fairly aware of the procedures and challenges to this operation. Often on approach; ATC will give headings off the STAR to intercept radials inbound to the IAF to accommodate spacing with other aircraft. I have seen this happen very spontaneously even if the airport is not busy. The approach procedure (ILS-2 05R) is rather challenging; but not insurmountable to an experienced crew. If a go around were to be executed; the MAP is not an easy boxed pattern back to the field. It would most likely require vectors well to the north and back onto the long approach path required to this runway due to terrain. Runways at MMMX are non-grooved; and pose operational challenges when wet. If an incident occurred with an inbound airplane; it could cause unforeseen delays. The MMMX briefing guide from the Airbus fleet spells out numerous other contingencies that can occur flying to this airport. I called the Dispatcher to discuss the planning of this flight; and shared my thoughts about the fuel load. He asked me how much fuel I wanted; and he gave me my request without incident. I added ZZZ1 as a precautionary alternate relative to the trends on the current METARS and nearby TAF. The flight operated 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.