Near midair collision.

Attributes
ACN	262652
Time
Date	199401
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : anu
State Reference	FO
Altitude	msl bound lower : 4400 msl bound upper : 4400
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Medium Transport, High Wing, 2 Turboprop Eng
Flight Phase	descent other
Route In Use	approach : visual enroute : direct enroute airway : anu
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Small Transport
Flight Phase	climbout : intermediate altitude
Route In Use	enroute : direct
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial pilot : cfi pilot : atp
Experience	flight time last 90 days : 200 flight time total : 4100 flight time type : 800
ASRS Report	262652
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : nmac non adherence : far
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	vertical : 500
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

We were flying from san juan, puerto rico, to antigua. We were cleared by tapa approach (119.1) for the visual approach to tapa (antigua). We started the descent from 10000 ft to the airport when we had a TCASII yellow alert (at about 4400 ft) for traffic. The TCASII screen showed a target at 11 O'clock without altitude. I looked to the outside to scan and I saw an aircraft at 11 O'clock climbing and converging with our path. The apt disengaged the autoplt and took manual control of the aircraft. He climbed to avoid the other aircraft. We estimated we were as close as 500 ft. We were never advised by the controller about this traffic in our vicinity. The other aircraft involved was an airliner twin-otter.

Original NASA ASRS Text

Title: NMAC.

Narrative: WE WERE FLYING FROM SAN JUAN, PUERTO RICO, TO ANTIGUA. WE WERE CLRED BY TAPA APCH (119.1) FOR THE VISUAL APCH TO TAPA (ANTIGUA). WE STARTED THE DSCNT FROM 10000 FT TO THE ARPT WHEN WE HAD A TCASII YELLOW ALERT (AT ABOUT 4400 FT) FOR TFC. THE TCASII SCREEN SHOWED A TARGET AT 11 O'CLOCK WITHOUT ALT. I LOOKED TO THE OUTSIDE TO SCAN AND I SAW AN ACFT AT 11 O'CLOCK CLBING AND CONVERGING WITH OUR PATH. THE APT DISENGAGED THE AUTOPLT AND TOOK MANUAL CTL OF THE ACFT. HE CLBED TO AVOID THE OTHER ACFT. WE ESTIMATED WE WERE AS CLOSE AS 500 FT. WE WERE NEVER ADVISED BY THE CTLR ABOUT THIS TFC IN OUR VICINITY. THE OTHER ACFT INVOLVED WAS AN AIRLINER TWIN-OTTER.

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.