A B737 flight crew have to take evasive action after takeoff from sju to avoid a DHC6.

Attributes
ACN	582378
Time
Date	200305
Day	Wed
Place
Locale Reference	airport : sju.airport
State Reference	PR
Altitude	agl bound lower : 300 agl bound upper : 400
Aircraft 1
Controlling Facilities	tower : sju.tower
Operator	common carrier : air carrier
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	climbout : initial climbout : takeoff
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tower : sju.tower
Operator	common carrier : air taxi
Make Model Name	Twin Otter DHC-6
Operating Under FAR Part	Part 135
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
ASRS Report	582378
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
ASRS Report	582714
Events
Anomaly	conflict : airborne critical
Independent Detector	other flight crewa other flight crewb
Resolutory Action	controller : issued advisory flight crew : took evasive action
Miss Distance	horizontal : 1000 vertical : 0
Supplementary
Problem Areas	ATC Human Performance Environmental Factor Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance

Narrative:

After rotation sju, DHC6 float plane appeared dead ahead, first noticed approximately 300 ft. Evasive action was required to miss the aircraft. Sju tower gave vague notification prior to takeoff. Aircraft was same altitude, approximately 1/2 mi at closest. Supplemental information from acn 582714: both aircraft were maneuvering to increase separation. TCASII showed a TA, but the RA was suppressed due to low altitude. We phoned tower after returning to sju to follow up, but did not receive a satisfactory explanation of how the float plane ended up at low altitude, off the end of the runway or why we were cleared for takeoff with it maneuvering in that area.

Original NASA ASRS Text

Title: A B737 FLT CREW HAVE TO TAKE EVASIVE ACTION AFTER TKOF FROM SJU TO AVOID A DHC6.

Narrative: AFTER ROTATION SJU, DHC6 FLOAT PLANE APPEARED DEAD AHEAD, FIRST NOTICED APPROX 300 FT. EVASIVE ACTION WAS REQUIRED TO MISS THE ACFT. SJU TWR GAVE VAGUE NOTIFICATION PRIOR TO TKOF. ACFT WAS SAME ALT, APPROX 1/2 MI AT CLOSEST. SUPPLEMENTAL INFO FROM ACN 582714: BOTH ACFT WERE MANEUVERING TO INCREASE SEPARATION. TCASII SHOWED A TA, BUT THE RA WAS SUPPRESSED DUE TO LOW ALT. WE PHONED TWR AFTER RETURNING TO SJU TO FOLLOW UP, BUT DID NOT RECEIVE A SATISFACTORY EXPLANATION OF HOW THE FLOAT PLANE ENDED UP AT LOW ALT, OFF THE END OF THE RWY OR WHY WE WERE CLRED FOR TKOF WITH IT MANEUVERING IN THAT AREA.

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.