Near midair collision while performing pipeline patrol.

Attributes
ACN	176451
Time
Date	199104
Day	Mon
Local Time Of Day	0001 To 0600
Place
Locale Reference	airport : den
State Reference	CO
Altitude	agl bound lower : 500 agl bound upper : 500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : pie
Operator	general aviation : corporate
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	cruise other
Flight Plan	None
Aircraft 2
Make Model Name	Small Aircraft, High Wing, 1 Eng, Retractable Gear
Flight Phase	cruise other
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial
Experience	flight time last 90 days : 150 flight time total : 2990
ASRS Report	176451
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Events
Anomaly	conflict : nmac
Independent Detector	other other : unspecified cockpit
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	vertical : 100
Supplementary
Primary Problem	Flight Crew Human Performance

Narrative:

While flying pipeline patrol I almost collided with another small aircraft. He was at my 2 O'clock position headed toward my 8 O'clock position. We were at approximately the same altitude. From the moment I saw him, I pulled up abruptly and he passed under me, approximately 3 seconds elapsed.

Original NASA ASRS Text

Title: NMAC WHILE PERFORMING PIPELINE PATROL.

Narrative: WHILE FLYING PIPELINE PATROL I ALMOST COLLIDED WITH ANOTHER SMA. HE WAS AT MY 2 O'CLOCK POS HEADED TOWARD MY 8 O'CLOCK POS. WE WERE AT APPROX THE SAME ALT. FROM THE MOMENT I SAW HIM, I PULLED UP ABRUPTLY AND HE PASSED UNDER ME, APPROX 3 SECS ELAPSED.

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.