Narrative:

We departed palo alto airport (pao) on a left downwind departure on a 160 magnetic heading. We were handed off to moffet tower (nuq) and checked in at 1;900 feet. Moffet tower instructed us to descend and maintain at or below 1;500 feet for traffic at 12 o'clock; 1.5 nm away. We acknowledged; and replied that we did not have the traffic in sight. As we began our descent out of 1;900 feet; we converged on a blue and white [aircraft] descending straight at us. The [aircraft] dove beneath our flight path and made a left turn (from their perspective) and we initiated a climb to avoid them. We believe the [aircraft] was on an instrument approach into san carlos airport (sql) and had received vectors for their initial approach. The [aircraft] appeared to have already descended below 2;000 feet before reaching their final approach point cuzup; which is why they converged on our position so rapidly.

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Original NASA ASRS Text

Title: Two GA pilots reported a NMAC while departing PAO.

Narrative: We departed Palo Alto Airport (PAO) on a left downwind departure on a 160 magnetic heading. We were handed off to Moffet Tower (NUQ) and checked in at 1;900 feet. Moffet Tower instructed us to descend and maintain at or below 1;500 feet for traffic at 12 o'clock; 1.5 nm away. We acknowledged; and replied that we did not have the traffic in sight. As we began our descent out of 1;900 feet; we converged on a blue and white [aircraft] descending straight at us. The [aircraft] dove beneath our flight path and made a left turn (from their perspective) and we initiated a climb to avoid them. We believe the [aircraft] was on an instrument approach into San Carlos Airport (SQL) and had received vectors for their initial approach. The [aircraft] appeared to have already descended below 2;000 feet before reaching their final approach point CUZUP; which is why they converged on our position so rapidly.

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.