Near midair collision between ATC small transport on flight check and GA small aircraft.

Attributes
ACN	104743
Time
Date	198902
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : lvk
State Reference	CA
Altitude	msl bound lower : 3050 msl bound upper : 3250
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : sck
Operator	common carrier : air taxi
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	descent : approach descent other
Route In Use	approach : straight in
Flight Plan	None
Aircraft 2
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Retractable Gear
Flight Phase	cruise other
Person 1
Affiliation	government : faa
Function	other personnel other
Qualification	pilot : instrument pilot : commercial pilot : cfi
Experience	flight time last 90 days : 15 flight time total : 6800 flight time type : 1
ASRS Report	104743
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	conflict : nmac
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 0 vertical : 200
Supplementary
Primary Problem	Flight Crew Human Performance

Narrative:

Sck approach gave traffic at 12 O'clock, 3500', 2 miles. Sck advised descent to 3000 from our VFR altitude of 3500'. PIC was under the hood executing the ILS into lvk. Check pilot was looking for traffic, primarily straight ahead and high. Traffic, an small aircraft appeared at about 1 O'clock and approximately 200' below. The check pilot took the controls and made an immediate pull up. If the evasive action had not been taken, it looked like it would have been very close, if not a collision. I am sure sck approach gave correct information as of the initial sighting, but did not notice the small aircraft descending; or the small aircraft may have had a faulty mode D. Corrective action: see and avoid.

Original NASA ASRS Text

Title: NMAC BETWEEN ATC SMT ON FLT CHECK AND GA SMA.

Narrative: SCK APCH GAVE TFC AT 12 O'CLOCK, 3500', 2 MILES. SCK ADVISED DSCNT TO 3000 FROM OUR VFR ALT OF 3500'. PIC WAS UNDER THE HOOD EXECUTING THE ILS INTO LVK. CHK PLT WAS LOOKING FOR TFC, PRIMARILY STRAIGHT AHEAD AND HIGH. TFC, AN SMA APPEARED AT ABOUT 1 O'CLOCK AND APPROX 200' BELOW. THE CHK PLT TOOK THE CONTROLS AND MADE AN IMMEDIATE PULL UP. IF THE EVASIVE ACTION HAD NOT BEEN TAKEN, IT LOOKED LIKE IT WOULD HAVE BEEN VERY CLOSE, IF NOT A COLLISION. I AM SURE SCK APCH GAVE CORRECT INFO AS OF THE INITIAL SIGHTING, BUT DID NOT NOTICE THE SMA DSNDING; OR THE SMA MAY HAVE HAD A FAULTY MODE D. CORRECTIVE ACTION: SEE AND AVOID.

Data retrieved from NASA's ASRS site as of August 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.