2 small aircraft's had an near midair collision.

Attributes
ACN	260428
Time
Date	199401
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : yum
State Reference	AZ
Altitude	msl bound lower : 4400 msl bound upper : 4400
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : mem
Operator	general aviation : personal
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Operating Under FAR Part	Part 91
Flight Phase	descent other
Route In Use	enroute airway : yum
Flight Plan	VFR
Aircraft 2
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : cfi pilot : atp
Experience	flight time last 90 days : 100 flight time total : 25000 flight time type : 50
ASRS Report	260428
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private
Events
Anomaly	conflict : nmac inflight encounter other non adherence : far other anomaly other
Independent Detector	other other : unspecified cockpit
Resolutory Action	flight crew : took evasive action
Consequence	faa : reviewed incident with flight crew
Miss Distance	horizontal : 150 vertical : 150
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Descending into yuma (into rising sun) and with excellent visibility otherwise (descending eastbound) a sharp turn to right was necessary to avoid a wbound high wing cessna southeast (172 type?) at 4500 ft. A discrete squawk was on transponder and we were in voice contact with yuma approach on 124.7. Approach stated the cessna was showing 3600 ft, but the pilot had been at 4500 ft for some mins and so stated to approach. Approach later acknowledged 4500 ft as being correct. The question: why didn't approach advise of the potential conflict regardless of altitude difference?

Original NASA ASRS Text

Title: 2 SMA'S HAD AN NMAC.

Narrative: DSNDING INTO YUMA (INTO RISING SUN) AND WITH EXCELLENT VISIBILITY OTHERWISE (DSNDING EBOUND) A SHARP TURN TO R WAS NECESSARY TO AVOID A WBOUND HIGH WING CESSNA SE (172 TYPE?) AT 4500 FT. A DISCRETE SQUAWK WAS ON XPONDER AND WE WERE IN VOICE CONTACT WITH YUMA APCH ON 124.7. APCH STATED THE CESSNA WAS SHOWING 3600 FT, BUT THE PLT HAD BEEN AT 4500 FT FOR SOME MINS AND SO STATED TO APCH. APCH LATER ACKNOWLEDGED 4500 FT AS BEING CORRECT. THE QUESTION: WHY DIDN'T APCH ADVISE OF THE POTENTIAL CONFLICT REGARDLESS OF ALT DIFFERENCE?

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.