Reporter's BE35 has critical encounter with C172 at aao.

Attributes
ACN	646483
Time
Date	200502
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : aao.airport
State Reference	KS
Altitude	msl single value : 2000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Bonanza 35
Operating Under FAR Part	Part 91
Flight Phase	descent : intermediate altitude descent : approach
Route In Use	approach : visual
Flight Plan	VFR
Aircraft 2
Operator	general aviation : personal
Make Model Name	Skyhawk 172/Cutlass 172
Flight Phase	descent : approach landing : missed approach
Person 1
Affiliation	other
Function	flight crew : single pilot
Experience	flight time last 90 days : 10 flight time total : 1700 flight time type : 700
ASRS Report	646483
Person 2
Affiliation	other
Function	flight crew : single pilot
Events
Anomaly	conflict : nmac conflict : airborne critical
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Miss Distance	horizontal : 500 vertical : 100
Supplementary
Problem Areas	Airport Flight Crew Human Performance Environmental Factor Airspace Structure
Primary Problem	Flight Crew Human Performance

Narrative:

The cessna was making a practice ILS approach and had announced she would terminate the approach with the published procedure. I was making an approach to the airport from the east and had announced my intention to cross midfield and enter a downwind to the same runway. My passenger and I both looked for the aircraft on the ILS but could not locate it. Apparently it was below our right wing for most of the time. As we approached midfield; we spotted the cessna climbing toward us. We pulled up and turned left; the cessna also turned left. It is possible that neither the pilot of the cessna nor the safety pilot saw us; as they were lower and had the high wing shielding them from seeing us. When making a practice approach; if there is conflicting VFR traffic; I make it a point to break off the approach before arriving at the airport threshold unless I have established visual contact and am assured of separation. Obviously; the cessna did not do that and was intent on flying the published missed approach; even though there was announced traffic in the vicinity of that procedure. Following the evasive maneuvering; the cessna announced again that she was flying the published missed approach (this is of no value to most pilots if they are not intimately familiar with that specific procedure). I re-entered downwind and proceeded to land.

Original NASA ASRS Text

Title: RPTR'S BE35 HAS CRITICAL ENCOUNTER WITH C172 AT AAO.

Narrative: THE CESSNA WAS MAKING A PRACTICE ILS APCH AND HAD ANNOUNCED SHE WOULD TERMINATE THE APCH WITH THE PUBLISHED PROC. I WAS MAKING AN APCH TO THE ARPT FROM THE E AND HAD ANNOUNCED MY INTENTION TO CROSS MIDFIELD AND ENTER A DOWNWIND TO THE SAME RWY. MY PAX AND I BOTH LOOKED FOR THE ACFT ON THE ILS BUT COULD NOT LOCATE IT. APPARENTLY IT WAS BELOW OUR R WING FOR MOST OF THE TIME. AS WE APCHED MIDFIELD; WE SPOTTED THE CESSNA CLBING TOWARD US. WE PULLED UP AND TURNED L; THE CESSNA ALSO TURNED L. IT IS POSSIBLE THAT NEITHER THE PLT OF THE CESSNA NOR THE SAFETY PLT SAW US; AS THEY WERE LOWER AND HAD THE HIGH WING SHIELDING THEM FROM SEEING US. WHEN MAKING A PRACTICE APCH; IF THERE IS CONFLICTING VFR TFC; I MAKE IT A POINT TO BREAK OFF THE APCH BEFORE ARRIVING AT THE ARPT THRESHOLD UNLESS I HAVE ESTABLISHED VISUAL CONTACT AND AM ASSURED OF SEPARATION. OBVIOUSLY; THE CESSNA DID NOT DO THAT AND WAS INTENT ON FLYING THE PUBLISHED MISSED APCH; EVEN THOUGH THERE WAS ANNOUNCED TFC IN THE VICINITY OF THAT PROC. FOLLOWING THE EVASIVE MANEUVERING; THE CESSNA ANNOUNCED AGAIN THAT SHE WAS FLYING THE PUBLISHED MISSED APCH (THIS IS OF NO VALUE TO MOST PLTS IF THEY ARE NOT INTIMATELY FAMILIAR WITH THAT SPECIFIC PROC). I RE-ENTERED DOWNWIND AND PROCEEDED TO LAND.

Data retrieved from NASA's ASRS site as of January 2009 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.