Small aircraft on photo mission descends below MSA.

Attributes
ACN	269933
Time
Date	199404
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : vgt
State Reference	NV
Altitude	msl bound lower : 2700 msl bound upper : 2700
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : vgt tower : hef
Operator	general aviation : instructional
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	cruise other
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : cfi pilot : atp
Experience	flight time last 90 days : 360 flight time total : 6150 flight time type : 335
ASRS Report	269933
Person 2
Affiliation	government : faa
Function	controller : local
Qualification	controller : non radar
Events
Anomaly	non adherence : far other spatial deviation
Independent Detector	other flight crewa
Resolutory Action	flight crew : became reoriented
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

The problem arose because more attention was paid to the subject property being photographed than the altitude. Since the property elevation (MSL) is not known exactly, and radar atl was available, only a guess at AGL was my gauge. The angles and altitudes should have been preplanned prior to takeoff.

Original NASA ASRS Text

Title: SMA ON PHOTO MISSION DSNDS BELOW MSA.

Narrative: THE PROB AROSE BECAUSE MORE ATTN WAS PAID TO THE SUBJECT PROPERTY BEING PHOTOGRAPHED THAN THE ALT. SINCE THE PROPERTY ELEVATION (MSL) IS NOT KNOWN EXACTLY, AND RADAR ATL WAS AVAILABLE, ONLY A GUESS AT AGL WAS MY GAUGE. THE ANGLES AND ALTS SHOULD HAVE BEEN PREPLANNED PRIOR TO TKOF.

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.