Narrative:

Westbound out of pwk at an initial cruising altitude of 1;800 MSL I was following a cessna 172 that was also heading west at a higher altitude. The cessna decided to descend to a lower altitude (he reported reaching 1;700 MSL) and as my aircraft was significantly faster I later overtook the cessna with just a 100 ft vertical separation and minimal horizontal separation. I should have observed the standard overtaking procedure of passing to the right of the cessna with adequate horizontal clearance.

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Original NASA ASRS Text

Title: The pilot of a VFR PA-28 failed to take appropriate corrective action when overtaking a Cessna 172 and passed just 100 FT over the Cessna.

Narrative: Westbound out of PWK at an initial cruising altitude of 1;800 MSL I was following a Cessna 172 that was also heading west at a higher altitude. The Cessna decided to descend to a lower altitude (he reported reaching 1;700 MSL) and as my aircraft was significantly faster I later overtook the Cessna with just a 100 FT vertical separation and minimal horizontal separation. I should have observed the standard overtaking procedure of passing to the right of the Cessna with adequate horizontal clearance.

Data retrieved from NASA's ASRS site as of July 2013 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.