BE9L pilot experiences temporary GPS outage in the vicinity of otg.

Attributes
ACN	638352
Time
Date	200411
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : otg.airport
State Reference	MN
Altitude	msl single value : 16000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zmp.artcc
Operator	general aviation : corporate
Make Model Name	King Air C90 E90
Operating Under FAR Part	Part 91
Navigation In Use	other
Flight Phase	cruise : level
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : corporate
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : multi engine pilot : commercial
Experience	flight time last 90 days : 100 flight time total : 2000 flight time type : 90
ASRS Report	638352
Person 2
Affiliation	government : faa
Function	controller : radar
Events
Anomaly	aircraft equipment problem : less severe non adherence : clearance other spatial deviation
Independent Detector	other controllera other flight crewa
Resolutory Action	aircraft : equipment problem dissipated controller : issued new clearance
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Navigational Facility Aircraft Environmental Factor
Primary Problem	Ambiguous

Narrative:

Had GPS 'flag' and 'poor reception.' display went blank. I maintained previous heading while troubleshooting. Switched over to VOR navigation temporarily, and after a few mins of monitoring the GPS unit, determined that GPS could not be safely utilized in this area. I was about to notify center of the GPS status when they called asking my heading/course. I told them the GPS was at least temporarily OTS. They gave me a heading 20 degrees left of my course. Apparently, no conflict occurred. There was no NOTAM or other information on GPS outage via FSS. 4 days before, I experienced the same outage within about 50 mi of otg. About 10 mi after notifying ATC the GPS came back on line and operated properly the rest of the week's flts. No GPS outages were reported, and during my briefing that morning, I even asked about GPS NOTAMS. None were listed.

Original NASA ASRS Text

Title: BE9L PLT EXPERIENCES TEMPORARY GPS OUTAGE IN THE VICINITY OF OTG.

Narrative: HAD GPS 'FLAG' AND 'POOR RECEPTION.' DISPLAY WENT BLANK. I MAINTAINED PREVIOUS HDG WHILE TROUBLESHOOTING. SWITCHED OVER TO VOR NAV TEMPORARILY, AND AFTER A FEW MINS OF MONITORING THE GPS UNIT, DETERMINED THAT GPS COULD NOT BE SAFELY UTILIZED IN THIS AREA. I WAS ABOUT TO NOTIFY CTR OF THE GPS STATUS WHEN THEY CALLED ASKING MY HDG/COURSE. I TOLD THEM THE GPS WAS AT LEAST TEMPORARILY OTS. THEY GAVE ME A HDG 20 DEGS L OF MY COURSE. APPARENTLY, NO CONFLICT OCCURRED. THERE WAS NO NOTAM OR OTHER INFO ON GPS OUTAGE VIA FSS. 4 DAYS BEFORE, I EXPERIENCED THE SAME OUTAGE WITHIN ABOUT 50 MI OF OTG. ABOUT 10 MI AFTER NOTIFYING ATC THE GPS CAME BACK ON LINE AND OPERATED PROPERLY THE REST OF THE WK'S FLTS. NO GPS OUTAGES WERE RPTED, AND DURING MY BRIEFING THAT MORNING, I EVEN ASKED ABOUT GPS NOTAMS. NONE WERE LISTED.

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.