An observer reported low level civil operation that was an agricultural spray aircraft.

Attributes
ACN	195759
Time
Date	199111
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : mhk
State Reference	KS
Altitude	agl bound lower : 5 agl bound upper : 500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : corporate
Make Model Name	Small Transport
Flight Phase	cruise other
Flight Plan	VFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial
Experience	flight time last 90 days : 300 flight time total : 12000 flight time type : 250
ASRS Report	195759
Person 2
Function	observation : observer
Events
Anomaly	other spatial deviation
Independent Detector	other other : unspecified
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Air Traffic Incident	other

Narrative:

On the morning of 11/wed/91 I was spraying the earthen dam of the tuttle creek reservoir for thistles as requested by army corps of engineers. After getting home had message on answering machine from FSDO office. They wanted more information on the report from a bird watcher who had reported a low flying airplane. The dam I was spraying is located in a river valley and I would guess the bird watcher was a ways away from the dam and from her viewing point I'd guess the airplane probably would appear to dive out of sight into the valley and reappear on the other side during a turn around. All applicable FARS were observed and no safety compromised and chemical used approved and registered, but the bird watcher probably thought I was doing a buzz job of the lake, cars, etc, as this is near a metropolitan area where agricultural operations are rare.

Original NASA ASRS Text

Title: AN OBSERVER RPTED LOW LEVEL CIVIL OP THAT WAS AN AGRICULTURAL SPRAY ACFT.

Narrative: ON THE MORNING OF 11/WED/91 I WAS SPRAYING THE EARTHEN DAM OF THE TUTTLE CREEK RESERVOIR FOR THISTLES AS REQUESTED BY ARMY CORPS OF ENGINEERS. AFTER GETTING HOME HAD MESSAGE ON ANSWERING MACHINE FROM FSDO OFFICE. THEY WANTED MORE INFO ON THE RPT FROM A BIRD WATCHER WHO HAD RPTED A LOW FLYING AIRPLANE. THE DAM I WAS SPRAYING IS LOCATED IN A RIVER VALLEY AND I WOULD GUESS THE BIRD WATCHER WAS A WAYS AWAY FROM THE DAM AND FROM HER VIEWING POINT I'D GUESS THE AIRPLANE PROBABLY WOULD APPEAR TO DIVE OUT OF SIGHT INTO THE VALLEY AND REAPPEAR ON THE OTHER SIDE DURING A TURN AROUND. ALL APPLICABLE FARS WERE OBSERVED AND NO SAFETY COMPROMISED AND CHEMICAL USED APPROVED AND REGISTERED, BUT THE BIRD WATCHER PROBABLY THOUGHT I WAS DOING A BUZZ JOB OF THE LAKE, CARS, ETC, AS THIS IS NEAR A METROPOLITAN AREA WHERE AGRICULTURAL OPS ARE RARE.

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.