Narrative:

After flying the NDB 22 approach at esn, we executed the published missed approach. As safety pilot and cfii, I was watching for local traffic; none was observed. When we recontacted bwi approach (in accordance with our IFR clearance), the bwi approach controller told us that he had a VFR target in our vicinity at 1800'. At that time he did not have us on radar (we were at 1500' climbing in the holding pattern). As we made the turn, from northeast to southwest, in observed the undercarriage of an small aircraft less than 50' above us. Apparently we were slightly in front of and below this aircraft when we made the turn. Had we proceeded straight ahead rather than turn, I am convinced there would have been a midair collision.

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Original NASA ASRS Text

Title: NMAC BETWEEN 2 SMA'S, ONE CLIMBING IN THE HOLDING PATTERN AFTER A MISSED APCH PROC.

Narrative: AFTER FLYING THE NDB 22 APCH AT ESN, WE EXECUTED THE PUBLISHED MISSED APCH. AS SAFETY PLT AND CFII, I WAS WATCHING FOR LCL TFC; NONE WAS OBSERVED. WHEN WE RECONTACTED BWI APCH (IN ACCORDANCE WITH OUR IFR CLRNC), THE BWI APCH CTLR TOLD US THAT HE HAD A VFR TARGET IN OUR VICINITY AT 1800'. AT THAT TIME HE DID NOT HAVE US ON RADAR (WE WERE AT 1500' CLBING IN THE HOLDING PATTERN). AS WE MADE THE TURN, FROM NE TO SW, IN OBSERVED THE UNDERCARRIAGE OF AN SMA LESS THAN 50' ABOVE US. APPARENTLY WE WERE SLIGHTLY IN FRONT OF AND BELOW THIS ACFT WHEN WE MADE THE TURN. HAD WE PROCEEDED STRAIGHT AHEAD RATHER THAN TURN, I AM CONVINCED THERE WOULD HAVE BEEN A MIDAIR COLLISION.

Data retrieved from NASA's ASRS site as of July 2007 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.