Pilot of atx cessna TU206 on climb out has near midair collision with a navajo in descent phase.

Attributes
ACN	409093
Time
Date	199807
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : boi
State Reference	ID
Altitude	msl bound lower : 5100 msl bound upper : 5100
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : boi tower : mia
Operator	common carrier : air taxi
Make Model Name	Cessna Stationair/Turbo Stationair 6
Operating Under FAR Part	Part 135
Flight Phase	climbout : intermediate altitude
Flight Plan	VFR
Aircraft 2
Make Model Name	PA-31 Navajo Chieftan/Mojave/Navajo T1020
Operating Under FAR Part	other : unknown
Flight Phase	descent : approach descent other
Person 1
Affiliation	company : air taxi
Function	flight crew : single pilot
Qualification	pilot : atp
Experience	flight time last 90 days : 80 flight time total : 6300 flight time type : 1000
ASRS Report	409093
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	conflict : nmac
Independent Detector	other flight crewa
Resolutory Action	flight crew : took evasive action other
Consequence	Other
Miss Distance	horizontal : 400 vertical : 50
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I departed boi aldape departure at or below 4000 ft. Contacted departure. Turned on course. Climbed to 4000 ft and leveled. Asked departure if cleared higher. Replied 'ah, uh, um, do not exceed 5500 ft.' she had 2 emergencys going with military warthogs. I looked around and at 5000 ft noticed navajo very close. Also noticed my transponder not on mode C. Usually controller alerts us to that upon switching from tower to departure. No traffic pointed out to me. Other aircraft spotted me first and dove to avoid. Sounded like a new controller. Perhaps no mode C (my error) contributed but no traffic was pointed out. Controller seemed confused. Probably long hold prior to departure and frustration at tower delays caused me to forget to turn on mode C. However it was not primary factor. The controller had acknowledged my initial contact after handoff from tower. Should have called out 'no mode C' or similar at that time. Collision was avoided by action of other pilot who also had not been given my position. He was noticeably upset also as he contacted me on multicom a few mins later.

Original NASA ASRS Text

Title: PLT OF ATX CESSNA TU206 ON CLBOUT HAS NMAC WITH A NAVAJO IN DSCNT PHASE.

Narrative: I DEPARTED BOI ALDAPE DEP AT OR BELOW 4000 FT. CONTACTED DEP. TURNED ON COURSE. CLBED TO 4000 FT AND LEVELED. ASKED DEP IF CLRED HIGHER. REPLIED 'AH, UH, UM, DO NOT EXCEED 5500 FT.' SHE HAD 2 EMERS GOING WITH MIL WARTHOGS. I LOOKED AROUND AND AT 5000 FT NOTICED NAVAJO VERY CLOSE. ALSO NOTICED MY XPONDER NOT ON MODE C. USUALLY CTLR ALERTS US TO THAT UPON SWITCHING FROM TWR TO DEP. NO TFC POINTED OUT TO ME. OTHER ACFT SPOTTED ME FIRST AND DOVE TO AVOID. SOUNDED LIKE A NEW CTLR. PERHAPS NO MODE C (MY ERROR) CONTRIBUTED BUT NO TFC WAS POINTED OUT. CTLR SEEMED CONFUSED. PROBABLY LONG HOLD PRIOR TO DEP AND FRUSTRATION AT TWR DELAYS CAUSED ME TO FORGET TO TURN ON MODE C. HOWEVER IT WAS NOT PRIMARY FACTOR. THE CTLR HAD ACKNOWLEDGED MY INITIAL CONTACT AFTER HDOF FROM TWR. SHOULD HAVE CALLED OUT 'NO MODE C' OR SIMILAR AT THAT TIME. COLLISION WAS AVOIDED BY ACTION OF OTHER PLT WHO ALSO HAD NOT BEEN GIVEN MY POS. HE WAS NOTICEABLY UPSET ALSO AS HE CONTACTED ME ON MULTICOM A FEW MINS LATER.

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.