Narrative:

I was leaving sig and entering [class] C airspace for sju. I was assigned a south heading until overhead the tower at sju. Upon reporting overhead; I was assigned a heading of 095; which had me under the path of a departing traffic from one of the runways below (runway 10). The traffic was a commercial jet flight which was less than two miles to my left. My heading had me [encounter] the wake turbulence of the jet. I lost 400-500 ft in the event and received trauma to the head. I was able to keep control of the aircraft; but my safety was compromised during the event.

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Original NASA ASRS Text

Title: A Piper Arrow pilot reported encountering wake turbulence from a commercial jet departure that passed over him. Pilot reported losing 400-500 FT altitude and receiving 'trauma to the head'.

Narrative: I was leaving SIG and entering [class] C airspace for SJU. I was assigned a south heading until overhead the Tower at SJU. Upon reporting overhead; I was assigned a heading of 095; which had me under the path of a departing traffic from one of the runways below (Runway 10). The traffic was a commercial jet flight which was less than two miles to my left. My heading had me [encounter] the wake turbulence of the jet. I lost 400-500 FT in the event and received trauma to the head. I was able to keep control of the aircraft; but my safety was compromised during the event.

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.