Narrative:

While on the arrival into bogota we were cleared to the vulam intersection then direct to bog VOR and cleared to cross the VOR at 12000 and 200 knots. We verified 12000 in the altitude selector and the FMC at the bog VOR. We were then cleared for the approach so I asked the captain to set 10000 which is the altitude at the final approach point and said we are protected because we have 12000 at the bog VOR. I said I would arm the approach closer in. Both VNAV and LNAV were armed and active. Approx 2 miles from the VOR the capt said we need to level of. Then I realized we had never leveled but continued our descent to approx 11600 feet. I hit altitude hold and the plane climbed back to 11800 feet at the same time the controller called us and told us to cross the bog VOR at 12000 feet. The airplane was in VNAV so I'm very confused as to why the aircraft continued its descent instead of leveling at 12000. Anyway there was no GPWS warning and we continued to bog without incident. In my opinion all procedures were followed to the letter however I allowed my confidence in the VNAV to not properly monitor our descent.

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Original NASA ASRS Text

Title: B737 First Officer reported descending below a feeder MEA during arrival to SKBO. VNAV and LNAV was being used to descend to 12000 feet at SKBO with 10000 feet in the MCP altitude window.

Narrative: While on the arrival into Bogota we were cleared to the VULAM intersection then direct to BOG VOR and cleared to cross the VOR at 12000 and 200 knots. We verified 12000 in the altitude selector and the FMC at the BOG VOR. We were then cleared for the approach so I asked the Captain to set 10000 which is the altitude at the Final Approach Point and said we are protected because we have 12000 at the BOG VOR. I said I would arm the approach closer in. Both VNAV and LNAV were armed and active. Approx 2 miles from the VOR the Capt said we need to level of. Then I realized we had never leveled but continued our descent to approx 11600 feet. I hit altitude hold and the plane climbed back to 11800 feet at the same time the controller called us and told us to cross the BOG VOR at 12000 feet. The airplane was in VNAV so I'm very confused as to why the aircraft continued its descent instead of leveling at 12000. Anyway there was no GPWS warning and we continued to BOG without incident. In my opinion all procedures were followed to the letter however I allowed my confidence in the VNAV to not properly monitor our descent.

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.