C172 on IFR approach to sts experienced a conflict with a fire air tanker.

Attributes
ACN	593374
Time
Date	200309
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : sts.airport
State Reference	CA
Altitude	msl single value : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : sts.tower
Operator	general aviation : personal
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Navigation In Use	other
Flight Phase	descent : approach
Route In Use	approach : instrument non precision arrival : on vectors
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tower : sts.tower
Operator	other
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Navigation In Use	other
Flight Phase	cruise : level
Person 1
Affiliation	other
Function	flight crew : single pilot instruction : trainee
Qualification	pilot : private
Experience	flight time last 90 days : 38 flight time total : 175 flight time type : 175
ASRS Report	593374
Person 2
Affiliation	other
Function	instruction : instructor
Events
Anomaly	conflict : airborne critical non adherence : published procedure
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 900 vertical : 50
Supplementary
Problem Areas	ATC Human Performance Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

We were on santa rosa GPS runway 14 approach. Had been cleared for approach by ZOA and had been handed off to santa rosa tower. Sts had asked for us to report at 5 mi. Since this was an IFR training flight (cross country), my safety pilot was also my instructor. He told me to turn 360 degrees left immediately, which I did. When I inquired why, he told me we were avoiding a possible conflict with an air attack fire tanker. Sts tower asked what our intentions were. My instructor informed the controller what we did and why. Tower came back with '360 not approved.' they then required us to cancel IFR and proceed VFR. Had we followed their rules and been correct, there was the potential for a conflict with the tanker, which was not on approach, and hadn't been on tower frequency. Tower, in effect, scolded us for making an unauthorized 360 degree turn on the approach even after we explained the reason. Tower followed their rules, and we took evasive action for safety reasons. The tanker never wavered from course, and may not even have seen us (hard to believe).

Original NASA ASRS Text

Title: C172 ON IFR APCH TO STS EXPERIENCED A CONFLICT WITH A FIRE AIR TANKER.

Narrative: WE WERE ON SANTA ROSA GPS RWY 14 APCH. HAD BEEN CLRED FOR APCH BY ZOA AND HAD BEEN HANDED OFF TO SANTA ROSA TWR. STS HAD ASKED FOR US TO RPT AT 5 MI. SINCE THIS WAS AN IFR TRAINING FLT (XCOUNTRY), MY SAFETY PLT WAS ALSO MY INSTRUCTOR. HE TOLD ME TO TURN 360 DEGS L IMMEDIATELY, WHICH I DID. WHEN I INQUIRED WHY, HE TOLD ME WE WERE AVOIDING A POSSIBLE CONFLICT WITH AN AIR ATTACK FIRE TANKER. STS TWR ASKED WHAT OUR INTENTIONS WERE. MY INSTRUCTOR INFORMED THE CTLR WHAT WE DID AND WHY. TWR CAME BACK WITH '360 NOT APPROVED.' THEY THEN REQUIRED US TO CANCEL IFR AND PROCEED VFR. HAD WE FOLLOWED THEIR RULES AND BEEN CORRECT, THERE WAS THE POTENTIAL FOR A CONFLICT WITH THE TANKER, WHICH WAS NOT ON APCH, AND HADN'T BEEN ON TWR FREQ. TWR, IN EFFECT, SCOLDED US FOR MAKING AN UNAUTH 360 DEG TURN ON THE APCH EVEN AFTER WE EXPLAINED THE REASON. TWR FOLLOWED THEIR RULES, AND WE TOOK EVASIVE ACTION FOR SAFETY REASONS. THE TANKER NEVER WAVERED FROM COURSE, AND MAY NOT EVEN HAVE SEEN US (HARD TO BELIEVE).

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.