Narrative:

I was asked to fly the leg -- when the owner returned from lunch, he was not prepared to fly. I did not check the adjacent airspace lateral limits, believing I could avoid the brize-norton eastern boundary after departing egtk runway 20, by a southerly heading. After takeoff, I was climbing and scanning for traffic. The frequency was congested as was the airspace. I was checking the VFR chart for the boundary of brize-norton control zone, while in the climb. I had several targets on the tcad, they were behind me. I continued to review the chart for my position relative to brize airspace and was attempting to contact brize radar. When I looked up, the seneca was passing overhead about 250-300 ft above. I don't think he saw me as he was in level flight and not maneuvering. Just afterwards, I was finally able to contact brize, the frequency was very busy. I was advised that I was already in the control zone. I was then given radar information and cleared to proceed on course after a few radar vectors for traffic. The problem arose because I took off without being sure of the eastern lateral limit of the brize-norton airspace. I thought I could remain clear by routing due south, but that was not the case. After takeoff, I became too occupied with navigation and failed to scan adequately for traffic. Then failed to remain clear of the airspace. In order to avoid future problems, I should always review airspace first and plan a route to keep me clear prior to takeoff. Then full attention can be allowed for traffic scanning.

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Original NASA ASRS Text

Title: NMAC BTWN A BEECH 90 IN CLASS C AIRSPACE WITHOUT CLRNC AND A PIPER SENECA PASSING 300 FT OVER THE TOP OF THE C90.

Narrative: I WAS ASKED TO FLY THE LEG -- WHEN THE OWNER RETURNED FROM LUNCH, HE WAS NOT PREPARED TO FLY. I DID NOT CHK THE ADJACENT AIRSPACE LATERAL LIMITS, BELIEVING I COULD AVOID THE BRIZE-NORTON EASTERN BOUNDARY AFTER DEPARTING EGTK RWY 20, BY A SOUTHERLY HDG. AFTER TKOF, I WAS CLBING AND SCANNING FOR TFC. THE FREQ WAS CONGESTED AS WAS THE AIRSPACE. I WAS CHKING THE VFR CHART FOR THE BOUNDARY OF BRIZE-NORTON CTL ZONE, WHILE IN THE CLB. I HAD SEVERAL TARGETS ON THE TCAD, THEY WERE BEHIND ME. I CONTINUED TO REVIEW THE CHART FOR MY POS RELATIVE TO BRIZE AIRSPACE AND WAS ATTEMPTING TO CONTACT BRIZE RADAR. WHEN I LOOKED UP, THE SENECA WAS PASSING OVERHEAD ABOUT 250-300 FT ABOVE. I DON'T THINK HE SAW ME AS HE WAS IN LEVEL FLT AND NOT MANEUVERING. JUST AFTERWARDS, I WAS FINALLY ABLE TO CONTACT BRIZE, THE FREQ WAS VERY BUSY. I WAS ADVISED THAT I WAS ALREADY IN THE CTL ZONE. I WAS THEN GIVEN RADAR INFO AND CLRED TO PROCEED ON COURSE AFTER A FEW RADAR VECTORS FOR TFC. THE PROB AROSE BECAUSE I TOOK OFF WITHOUT BEING SURE OF THE EASTERN LATERAL LIMIT OF THE BRIZE-NORTON AIRSPACE. I THOUGHT I COULD REMAIN CLR BY ROUTING DUE S, BUT THAT WAS NOT THE CASE. AFTER TKOF, I BECAME TOO OCCUPIED WITH NAV AND FAILED TO SCAN ADEQUATELY FOR TFC. THEN FAILED TO REMAIN CLR OF THE AIRSPACE. IN ORDER TO AVOID FUTURE PROBS, I SHOULD ALWAYS REVIEW AIRSPACE FIRST AND PLAN A RTE TO KEEP ME CLR PRIOR TO TKOF. THEN FULL ATTN CAN BE ALLOWED FOR TFC SCANNING.

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.