A pilot entered a tower controller assigned downwind for runway 4 and had a near miss with an aircra...

Narrative:

I approached the airport from the east. The ATIS announced runway 4 active; winds 3 KTS. Tower assigned me a right downwind for runway 22. I wrote down the clearance and read it back as such. Then; I circumnavigated the airport to the north and made a 45 degree entry accordingly. Just after entering the downwind; I observed a single engine cessna coming in the opposite direction; slightly to my right (closer to the runway). I turned left and descended to move away. The other aircraft the tower; 'where did that bonanza come from?'. The tower replied 'from the east' and upon being told that we had passed opposite directions; asked me what I had done. He asserted I had been assigned a left downwind for runway 4. I replied that I had been assigned a right downwind for runway 22; had read it back; and had circumnavigated. The controller said to query a dubious instruction next time. Upon his new instruction; reversed course; joined a downwind for runway 4; and landed without further incident. In retrospect; I had doubted the clearance but with the wind so light; believed a runway change had taken place; I had also been reluctant to question the authority of the controller. In an odd coincidence; later the day; I departed the same airport and assigned a different runway from two preceding aircraft. I certainly questioned the assignment that time. Next time reading back is not enough. Call attention to a clearance that seems inappropriate.

Original NASA ASRS Text

Title: A pilot entered a Tower Controller assigned downwind for Runway 4 and had a near miss with an aircraft on a Tower assigned downwind for Runway 22. ATC told the pilot to question his clearance.

Narrative: I approached the airport from the east. The ATIS announced Runway 4 active; winds 3 KTS. Tower assigned me a right downwind for Runway 22. I wrote down the clearance and read it back as such. Then; I circumnavigated the airport to the north and made a 45 degree entry accordingly. Just after entering the downwind; I observed a single engine Cessna coming in the opposite direction; slightly to my right (closer to the runway). I turned left and descended to move away. The other aircraft the tower; 'Where did that Bonanza come from?'. The Tower replied 'From the East' and upon being told that we had passed opposite directions; asked me what I had done. He asserted I had been assigned a left downwind for Runway 4. I replied that I had been assigned a right downwind for Runway 22; had read it back; and had circumnavigated. The Controller said to query a dubious instruction next time. Upon his new instruction; reversed course; joined a downwind for Runway 4; and landed without further incident. In retrospect; I had doubted the clearance but with the wind so light; believed a runway change had taken place; I had also been reluctant to question the authority of the Controller. In an odd coincidence; later the day; I departed the same airport and assigned a different runway from two preceding aircraft. I certainly questioned the assignment that time. Next time reading back is not enough. Call attention to a clearance that seems inappropriate.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	911644
Time
Date	201009
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Bonanza 35
Operating Under FAR Part	Part 91
Flight Phase	Landing
Route In Use	Visual Approach
Flight Plan	None
Aircraft 2
Make Model Name	Small Aircraft High Wing 1 Eng Fixed Gear
Flight Phase	Final Approach Landing
Route In Use	Visual Approach
Person 1
Function	Pilot Flying Single Pilot
Qualification	Flight Crew Instrument Flight Crew Private
Experience	Flight Crew Last 90 Days 38 Flight Crew Total 2465 Flight Crew Type 1924
Events
Anomaly	ATC Issue All Types Conflict NMAC
Miss Distance	Horizontal 400 Vertical 30

A pilot entered a tower controller assigned downwind for runway 4 and had a near miss with an aircraft on a tower assigned downwind for runway 22. ATC told the pilot to question his clearance.