Antique biplane and an small aircraft twin have near midair collision in traffic pattern.

Attributes
ACN	234498
Time
Date	199302
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : apa
State Reference	CO
Altitude	msl bound lower : 6500 msl bound upper : 6500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : apa
Operator	general aviation : personal
Make Model Name	Small Aircraft
Flight Phase	landing : go around other
Flight Plan	VFR
Aircraft 2
Make Model Name	Small Aircraft, Low Wing, 2 Eng, Retractable Gear
Flight Phase	climbout : initial other
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial pilot : atp
Experience	flight time last 90 days : 60 flight time total : 2500 flight time type : 4
ASRS Report	234498
Person 2
Affiliation	Other
Function	flight crew : single pilot
Events
Anomaly	aircraft equipment problem : critical conflict : nmac other spatial deviation
Independent Detector	other controllera other flight crewa
Resolutory Action	other
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Tower cleared me for low approach to runway 35L. Wind was reported at 230 degrees at 10 KTS. After approximately 1000 ft down runway 35L, I pulled up and applied climb power. After approximately 30 seconds, I noticed 2-300 RPM fluctuations in tach indications. I continued the climb trying to determine engine situation and maintaining runway heading 350 degrees. Wind now 250 degrees at 10 KTS (per tower). Approximately 2 mins later, tower asked me to verify low approach to runway 35L. I verified and stated I was now left crosswind turn. A few seconds later, tower advised me that it appears you have drifted off and into departure path of runway 35R, use caution. 30 seconds later, I advised tower that I was going to have to land and requested runway 28. Engine indications were still erratic and continued with a normal landing on runway 28. Small aircraft Y was doing touch and goes on runway 35R while I was upwind on runway 35L and reported a near miss to tower. On ground at my hangar, I called tower on land line and relayed pertinent information. Several factors play into this: 1) not enough crosswind correction for variable wind conditions. 2) failure of overtaking aircraft to give (yield) right of way. 3) no tower communication advising of possible conflict until after the fact!

Original NASA ASRS Text

Title: ANTIQUE BIPLANE AND AN SMA TWIN HAVE NMAC IN TFC PATTERN.

Narrative: TWR CLRED ME FOR LOW APCH TO RWY 35L. WIND WAS RPTED AT 230 DEGS AT 10 KTS. AFTER APPROX 1000 FT DOWN RWY 35L, I PULLED UP AND APPLIED CLB PWR. AFTER APPROX 30 SECONDS, I NOTICED 2-300 RPM FLUCTUATIONS IN TACH INDICATIONS. I CONTINUED THE CLB TRYING TO DETERMINE ENG SIT AND MAINTAINING RWY HDG 350 DEGS. WIND NOW 250 DEGS AT 10 KTS (PER TWR). APPROX 2 MINS LATER, TWR ASKED ME TO VERIFY LOW APCH TO RWY 35L. I VERIFIED AND STATED I WAS NOW L XWIND TURN. A FEW SECONDS LATER, TWR ADVISED ME THAT IT APPEARS YOU HAVE DRIFTED OFF AND INTO DEP PATH OF RWY 35R, USE CAUTION. 30 SECONDS LATER, I ADVISED TWR THAT I WAS GOING TO HAVE TO LAND AND REQUESTED RWY 28. ENG INDICATIONS WERE STILL ERRATIC AND CONTINUED WITH A NORMAL LNDG ON RWY 28. SMA Y WAS DOING TOUCH AND GOES ON RWY 35R WHILE I WAS UPWIND ON RWY 35L AND RPTED A NEAR MISS TO TWR. ON GND AT MY HANGAR, I CALLED TWR ON LAND LINE AND RELAYED PERTINENT INFO. SEVERAL FACTORS PLAY INTO THIS: 1) NOT ENOUGH XWIND CORRECTION FOR VARIABLE WIND CONDITIONS. 2) FAILURE OF OVERTAKING ACFT TO GIVE (YIELD) RIGHT OF WAY. 3) NO TWR COM ADVISING OF POSSIBLE CONFLICT UNTIL AFTER THE FACT!

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.