Small aircraft has near midair collision with a second small aircraft on final. Makes a go around.

Attributes
ACN	250004
Time
Date	199308
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : sff
State Reference	WA
Altitude	msl bound lower : 2500 msl bound upper : 2500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : sff
Operator	general aviation : personal
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	descent : approach landing : go around
Flight Plan	None
Aircraft 2
Operator	general aviation : personal
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	descent : approach
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial pilot : instrument
Experience	flight time last 90 days : 14 flight time total : 2739 flight time type : 2591
ASRS Report	250004
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Events
Anomaly	conflict : nmac non adherence : clearance other spatial deviation
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action other
Consequence	Other
Miss Distance	horizontal : 250 vertical : 50
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I was practicing touch-and-goes. An small aircraft Y was approaching the airport for landing, from the north, while I was on downwind for runway 3L. I saw the other aircraft as I turned base. The aircraft acknowledged instruction from the tower to follow behind me and use runway 3R. As I turned final, I saw the small aircraft Y lined up for runway 3L, behind and below me. The tower told the small aircraft Y pilot to use runway 3R, again. Because of the confused situation, the possibility that the small aircraft Y pilot was not understanding, and the fact that I could not see the small aircraft Y behind me, I 'went around.' there had been more than usual radio activity at the airport. Tower xmissions were blocked several times. Tower tried a second transmitter to see if it would be stronger. I couldn't see any difference. In retrospect, both tower transmitters were clear and loud, but rather scratchy.

Original NASA ASRS Text

Title: SMA HAS NMAC WITH A SECOND SMA ON FINAL. MAKES A GAR.

Narrative: I WAS PRACTICING TOUCH-AND-GOES. AN SMA Y WAS APCHING THE ARPT FOR LNDG, FROM THE N, WHILE I WAS ON DOWNWIND FOR RWY 3L. I SAW THE OTHER ACFT AS I TURNED BASE. THE ACFT ACKNOWLEDGED INSTRUCTION FROM THE TWR TO FOLLOW BEHIND ME AND USE RWY 3R. AS I TURNED FINAL, I SAW THE SMA Y LINED UP FOR RWY 3L, BEHIND AND BELOW ME. THE TWR TOLD THE SMA Y PLT TO USE RWY 3R, AGAIN. BECAUSE OF THE CONFUSED SIT, THE POSSIBILITY THAT THE SMA Y PLT WAS NOT UNDERSTANDING, AND THE FACT THAT I COULD NOT SEE THE SMA Y BEHIND ME, I 'WENT AROUND.' THERE HAD BEEN MORE THAN USUAL RADIO ACTIVITY AT THE ARPT. TWR XMISSIONS WERE BLOCKED SEVERAL TIMES. TWR TRIED A SECOND XMITTER TO SEE IF IT WOULD BE STRONGER. I COULDN'T SEE ANY DIFFERENCE. IN RETROSPECT, BOTH TWR XMITTERS WERE CLR AND LOUD, BUT RATHER SCRATCHY.

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.