AC50 near midair collision with opposite direction same altitude traffic, a PA-31.

Attributes
ACN	361057
Time
Date	199702
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : bfi
State Reference	WA
Altitude	msl bound lower : 1000 msl bound upper : 1400
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : sea
Operator	other
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	climbout : intermediate altitude landing : missed approach
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Retractable Gear
Flight Phase	cruise other
Route In Use	enroute : direct
Person 1
Affiliation	government other
Function	flight crew : captain instruction : trainee
Qualification	pilot : atp
Experience	flight time last 90 days : 40 flight time total : 5400 flight time type : 1
ASRS Report	361057
Person 2
Affiliation	government other
Function	flight crew : first officer instruction : instructor oversight : pic
Qualification	pilot : atp pilot : cfi pilot : commercial pilot : instrument
Events
Anomaly	conflict : nmac non adherence : far non adherence : published procedure other anomaly other other anomaly other
Independent Detector	other controllera other flight crewa
Resolutory Action	none taken : insufficient time
Consequence	Other
Miss Distance	horizontal : 50 vertical : 400
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation other

Narrative:

On missed approach from bfi back course runway 31L, tower instructed us to maintain 1000 ft rather than climb to 2000 ft as per our missed approach instructions. Instructor pilot asked tower for confirmation to maintain 1000 ft at 4 NM and were told to contact departure. Departure acknowledged our call and issued traffic at 11 O'clock and 1/2 mi. I had left 1000 ft for 2000 ft and at 1400 ft the NAVAID passed 400 ft below going the opposite direction.

Original NASA ASRS Text

Title: AC50 NMAC WITH OPPOSITE DIRECTION SAME ALT TFC, A PA-31.

Narrative: ON MISSED APCH FROM BFI BACK COURSE RWY 31L, TWR INSTRUCTED US TO MAINTAIN 1000 FT RATHER THAN CLB TO 2000 FT AS PER OUR MISSED APCH INSTRUCTIONS. INSTRUCTOR PLT ASKED TWR FOR CONFIRMATION TO MAINTAIN 1000 FT AT 4 NM AND WERE TOLD TO CONTACT DEP. DEP ACKNOWLEDGED OUR CALL AND ISSUED TFC AT 11 O'CLOCK AND 1/2 MI. I HAD LEFT 1000 FT FOR 2000 FT AND AT 1400 FT THE NAVAID PASSED 400 FT BELOW GOING THE OPPOSITE DIRECTION.

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.