Narrative:

Upon receiving my frequency change handoff from ZZZ tower; having just taken off from there; I tuned to pt. Mugu on 124.70 to request flight following to vny at 3;500 feet. They responded that they were too busy to safely accommodate the request. Understanding what that implied to the busyness of the airspace around me; I proceeded with the flight; maintaining an extra vigilant scan of the sky outside; and monitoring 124.7 and then socal on 134.2 as appropriate; while cruising at an altitude of 3;500 feet. Roughly 13 nm from vny; over simi valley; following the 118 freeway towards vny; I saw aircraft Y passing directly in front of my plane from the left side of my windshield to the right in what appeared to be a climbing 180 turn to the east. With a high closure rate we were ultimately under 50 feet apart. I brought my power back to idle and made a descending turn to the left with a bank of over 50 degrees. Even so it seemed like we would still impact. With our separation at that point being under 10 feet. No contact was made; and upon rolling back to straight and level flight I could see aircraft Y flying in straight and level flight as well; a few hundred feet above me and now with about half a mile of separation and furthering. No one came on frequency (134.2) to report this; that I observed; and after a few minutes I proceeded to switch over to vny and call tower to report that I was inbound for landing. My interpretation of the facts stated above is that aircraft Y was not on 134.2; or on any kind of flight following/plan; was engaging in either a training maneuver or evasive maneuver to avoid collision; though not adhering to the idea that two aircrafts in threat of colliding shall each turn to the right; and were at the wrong altitude for their originally westbound heading prior to turning 180 degrees to the east. No strobes; nav or landing lights could be observed on aircraft Y post near miss. It appeared that there were two people aboard aircraft Y.

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Original NASA ASRS Text

Title: GA pilot reported an NMAC at VNY airport.

Narrative: Upon receiving my frequency change handoff from ZZZ Tower; having just taken off from there; I tuned to Pt. Mugu on 124.70 to request flight following to VNY at 3;500 feet. They responded that they were too busy to safely accommodate the request. Understanding what that implied to the busyness of the airspace around me; I proceeded with the flight; maintaining an extra vigilant scan of the sky outside; and monitoring 124.7 and then SoCal on 134.2 as appropriate; while cruising at an altitude of 3;500 feet. Roughly 13 nm from VNY; over Simi Valley; following the 118 freeway towards VNY; I saw Aircraft Y passing directly in front of my plane from the left side of my windshield to the right in what appeared to be a climbing 180 turn to the east. With a high closure rate we were ultimately under 50 feet apart. I brought my power back to idle and made a descending turn to the left with a bank of over 50 degrees. Even so it seemed like we would still impact. With our separation at that point being under 10 feet. No contact was made; and upon rolling back to straight and level flight I could see Aircraft Y flying in straight and level flight as well; a few hundred feet above me and now with about half a mile of separation and furthering. No one came on frequency (134.2) to report this; that I observed; and after a few minutes I proceeded to switch over to VNY and call Tower to report that I was inbound for landing. My interpretation of the facts stated above is that Aircraft Y was not on 134.2; or on any kind of flight following/plan; was engaging in either a training maneuver or evasive maneuver to avoid collision; though not adhering to the idea that two aircrafts in threat of colliding shall each turn to the right; and were at the wrong altitude for their originally westbound heading prior to turning 180 degrees to the East. No strobes; nav or landing lights could be observed on Aircraft Y post near miss. It appeared that there were two people aboard Aircraft Y.

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.