Confusion in the traffic pattern leads to an near midair collision.

Attributes
ACN	273982
Time
Date	199406
Day	Thu
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : bed
State Reference	MA
Altitude	agl bound lower : 1000 agl bound upper : 1000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : bed
Operator	general aviation : instructional
Make Model Name	Sierra 24
Operating Under FAR Part	Part 91
Flight Phase	other
Flight Plan	None
Aircraft 2
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	other
Person 1
Affiliation	Other
Function	flight crew : single pilot instruction : trainee
Qualification	pilot : instrument pilot : cfi pilot : commercial
ASRS Report	273982
Person 2
Affiliation	Other
Function	flight crew : single pilot instruction : instructor
Qualification	pilot : commercial pilot : instrument pilot : cfi
Events
Anomaly	conflict : nmac other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 200 vertical : 200
Supplementary
Primary Problem	Flight Crew Human Performance

Narrative:

I was taking instruction for refamiliarization in a beech sierra C-24R. I flew left seat with an instructor in the right seat. After several practice touch-and-goes, I was on left downwind for a full stop landing. The tower instructed me to follow a navajo on downwind. I acknowledged having the navajo in sight. When I was on about a 2 mi final following the navajo, a high wing cessna (probably C-172) who had been behind me on downwind, began approaching from the left and above, apparently on a high left base. I pointed this out to the tower. The tower told the cessna to follow the sierra (my aircraft). The cessna entered a left turn onto final in front of me. In his turn he announced he had the sierra in sight. Because of his turn attitude, the cessna pilot could not have seen me. He probably mistook the navajo for the sierra. I was about to fly directly under the cessna, so I made an immediate left turn, announcing this to the tower. I then rejoined the left downwind behind another cessna on downwind and informed the tower of my position. The controller was apparently confused because he amended my clearance to land behind the first cessna, then re-amended the clearance to land behind the second cessna. This is a good example of the importance of continuous vigilance in the traffic pattern, even in a tower environment.

Original NASA ASRS Text

Title: CONFUSION IN THE TFC PATTERN LEADS TO AN NMAC.

Narrative: I WAS TAKING INSTRUCTION FOR REFAMILIARIZATION IN A BEECH SIERRA C-24R. I FLEW L SEAT WITH AN INSTRUCTOR IN THE R SEAT. AFTER SEVERAL PRACTICE TOUCH-AND-GOES, I WAS ON L DOWNWIND FOR A FULL STOP LNDG. THE TWR INSTRUCTED ME TO FOLLOW A NAVAJO ON DOWNWIND. I ACKNOWLEDGED HAVING THE NAVAJO IN SIGHT. WHEN I WAS ON ABOUT A 2 MI FINAL FOLLOWING THE NAVAJO, A HIGH WING CESSNA (PROBABLY C-172) WHO HAD BEEN BEHIND ME ON DOWNWIND, BEGAN APCHING FROM THE L AND ABOVE, APPARENTLY ON A HIGH L BASE. I POINTED THIS OUT TO THE TWR. THE TWR TOLD THE CESSNA TO FOLLOW THE SIERRA (MY ACFT). THE CESSNA ENTERED A L TURN ONTO FINAL IN FRONT OF ME. IN HIS TURN HE ANNOUNCED HE HAD THE SIERRA IN SIGHT. BECAUSE OF HIS TURN ATTITUDE, THE CESSNA PLT COULD NOT HAVE SEEN ME. HE PROBABLY MISTOOK THE NAVAJO FOR THE SIERRA. I WAS ABOUT TO FLY DIRECTLY UNDER THE CESSNA, SO I MADE AN IMMEDIATE L TURN, ANNOUNCING THIS TO THE TWR. I THEN REJOINED THE L DOWNWIND BEHIND ANOTHER CESSNA ON DOWNWIND AND INFORMED THE TWR OF MY POS. THE CTLR WAS APPARENTLY CONFUSED BECAUSE HE AMENDED MY CLRNC TO LAND BEHIND THE FIRST CESSNA, THEN RE-AMENDED THE CLRNC TO LAND BEHIND THE SECOND CESSNA. THIS IS A GOOD EXAMPLE OF THE IMPORTANCE OF CONTINUOUS VIGILANCE IN THE TFC PATTERN, EVEN IN A TWR ENVIRONMENT.

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.