Narrative:

My partner and I launched from the fixed wing hangar at vny for a staggs east crossing. Upon reaching 1300 feet; I called the tower and advised of my altitude and asked if I was approved to cross. The tower approved me to cross both runways. As I was approaching the 405 freeway; the controller advised I had traffic; a fixed wing; northbound at 1:00 o'clock; slightly low. I observed a fixed wing aircraft passing my one o'clock in the pattern above me. I advised I had the traffic and would maintain visual. A few seconds later; a fixed wing aircraft passed northbound in front of me approximately 25 to 50 feet below me. We were approximately two seconds from converging. I advised the tower I had the traffic that had just passed right in front of me. The tower acknowledged and apologized. Upon landing I contacted the tower supervisor and explained what had happened and asked what went wrong. He talked to the tower controller and then explained that the fixed wing aircraft had entered the pattern from burbank airspace and was advised to maintain 1800 feet. Somehow he lost altitude down to 1200 feet. The fixed wing was on with the regular tower and I was on with the helicopters and the information did not get passed efficiently. He apologized and advised that they would try and do better in the future. I thanked him. I had just passed the runways and had been concentrating on traffic on final or taking off. Once past the runways; I did not resume a thorough scan around me and was somewhat concentrating on my new glass panel in order to observe my altitude. It took me a few seconds longer than normal to locate it in my instrument scan. I believe my attention was also diverted to the fixed wing I observed in the pattern when I was told about the traffic. My scan was limited to where I expected fixed wing traffic to be. When I observed a fixed wing where I expected to see it; I watched it without continuing my scan further to the sides. I did not expect a fixed wing to be at my altitude or below when they were suppose to be 500 feet above me. The tower could have used better terminology than 'slightly low' as I believed that to be 1700 feet or so; instead of 1800 feet; but not 1200 to 1300 feet. I probably relied too much on ATC to call out traffic while in the pattern.

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Original NASA ASRS Text

Title: Helicopter and fixed wing have NMAC at VNY.

Narrative: My partner and I launched from the fixed wing hangar at VNY for a Staggs east crossing. Upon reaching 1300 feet; I called the tower and advised of my altitude and asked if I was approved to cross. The tower approved me to cross both runways. As I was approaching the 405 freeway; the controller advised I had traffic; a fixed wing; northbound at 1:00 o'clock; slightly low. I observed a fixed wing aircraft passing my one o'clock in the pattern above me. I advised I had the traffic and would maintain visual. A few seconds later; a fixed wing aircraft passed northbound in front of me approximately 25 to 50 feet below me. We were approximately two seconds from converging. I advised the tower I had the traffic that had just passed right in front of me. The tower acknowledged and apologized. Upon landing I contacted the Tower Supervisor and explained what had happened and asked what went wrong. He talked to the Tower Controller and then explained that the fixed wing aircraft had entered the pattern from Burbank Airspace and was advised to maintain 1800 feet. Somehow he lost altitude down to 1200 feet. The fixed wing was on with the regular Tower and I was on with the helicopters and the information did not get passed efficiently. He apologized and advised that they would try and do better in the future. I thanked him. I had just passed the runways and had been concentrating on traffic on final or taking off. Once past the runways; I did not resume a thorough scan around me and was somewhat concentrating on my new glass panel in order to observe my altitude. It took me a few seconds longer than normal to locate it in my instrument scan. I believe my attention was also diverted to the fixed wing I observed in the pattern when I was told about the traffic. My scan was limited to where I expected fixed wing traffic to be. When I observed a fixed wing where I expected to see it; I watched it without continuing my scan further to the sides. I did not expect a fixed wing to be at my altitude or below when they were suppose to be 500 feet above me. The tower could have used better terminology than 'slightly low' as I believed that to be 1700 feet or so; instead of 1800 feet; but not 1200 to 1300 feet. I probably relied too much on ATC to call out traffic while in the pattern.

Data retrieved from NASA's ASRS site as of April 2012 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.