Narrative:

Departed P53 direct to mkp bcn. Climbed to 3500 ft MSL. Course and altitude avoid agc and pit airspace. Departed mkp 005 degrees. Initiated climb out of 3500 ft at springdale stack. Cruise climb outside of class B airspace about 4000 ft MSL. Observed opposite direction traffic above. Stopped climb at 5500 ft MSL. When clear of traffic resumed climb to 6500 ft MSL. Cruise heading at 6500 ft was 355 degrees. Upon arrival at destination advised by ATC of climb through class B airspace and close encounter with other traffic. Although in controled airspace, both geographical and navigation fixes placed our aircraft either below or outside of class B airspace. Opposing traffic was obscured by climb attitude. Suggest low cost TCASII for GA aircraft.

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Original NASA ASRS Text

Title: A PA28 PLT DISPUTES THAT HE FLEW THROUGH CLASS B AIRSPACE AND HAD AN NMAC WITH A DH8.

Narrative: DEPARTED P53 DIRECT TO MKP BCN. CLBED TO 3500 FT MSL. COURSE AND ALT AVOID AGC AND PIT AIRSPACE. DEPARTED MKP 005 DEGS. INITIATED CLBOUT OF 3500 FT AT SPRINGDALE STACK. CRUISE CLB OUTSIDE OF CLASS B AIRSPACE ABOUT 4000 FT MSL. OBSERVED OPPOSITE DIRECTION TFC ABOVE. STOPPED CLB AT 5500 FT MSL. WHEN CLR OF TFC RESUMED CLB TO 6500 FT MSL. CRUISE HEADING AT 6500 FT WAS 355 DEGS. UPON ARR AT DEST ADVISED BY ATC OF CLB THROUGH CLASS B AIRSPACE AND CLOSE ENCOUNTER WITH OTHER TFC. ALTHOUGH IN CTLED AIRSPACE, BOTH GEOGRAPHICAL AND NAV FIXES PLACED OUR ACFT EITHER BELOW OR OUTSIDE OF CLASS B AIRSPACE. OPPOSING TFC WAS OBSCURED BY CLB ATTITUDE. SUGGEST LOW COST TCASII FOR GA ACFT.

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.