Narrative:

I was flying a piper archer under visual flight rules. I was familiar with the area. I was flying south around highway 55; about 3-4 miles west of 494 near wayzata; minnesota. This area is under the 4000 ft shelf of the msp class bravo. I was tuned to fcm tower as I already made my 10 mile out call. The wind was out of the east. I received a traffic warning from my G1000. It pointed out traffic to my right at about 4 or 5 o'clock and 300 feet above me. I turned and looked over my shoulder to see an airliner heading right for me with his lights on. At that moment I would guess the airplane was less than 1 mile away from me. I put my plane in an emergency dive. I pulled up at about 2;500 feet MSL. By this time the plane was passing to my rear and left. I returned and landed at fcm but was quite shaken up. I looked up the plane on [an app] which shows a 737-800 flying in the same area at the same time. The track shows the plane descending to 3;900 ft MSL a couple miles prior to entering the 3000 foot ring of the class bravo. I was not on flight following at the time; but my trip was recorded in [the app]. My conclusion is the actions of the flight crew in the other plane caused them to leave the protected space of the class bravo. This caused a near miss with another aircraft; and caused [me] to do emergency evasive maneuvers over a highly populated area.

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Original NASA ASRS Text

Title: Piper Archer pilot reported an airborne conflict with a B737-800 that had apparently descended below the MSP Class B airspace on arrival to MSP.

Narrative: I was flying a Piper Archer under visual flight rules. I was familiar with the area. I was flying south around highway 55; about 3-4 miles west of 494 near Wayzata; Minnesota. This area is under the 4000 ft shelf of the MSP class Bravo. I was tuned to FCM Tower as I already made my 10 mile out call. The wind was out of the east. I received a traffic warning from my G1000. It pointed out traffic to my right at about 4 or 5 o'clock and 300 feet above me. I turned and looked over my shoulder to see an airliner heading right for me with his lights on. At that moment I would guess the airplane was less than 1 mile away from me. I put my plane in an emergency dive. I pulled up at about 2;500 feet MSL. By this time the plane was passing to my rear and left. I returned and landed at FCM but was quite shaken up. I looked up the plane on [an app] which shows a 737-800 flying in the same area at the same time. The track shows the plane descending to 3;900 ft MSL a couple miles prior to entering the 3000 foot ring of the Class Bravo. I was not on flight following at the time; but my trip was recorded in [the app]. My conclusion is the actions of the flight crew in the other plane caused them to leave the protected space of the Class Bravo. This caused a near miss with another aircraft; and caused [me] to do emergency evasive maneuvers over a highly populated area.

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.