Narrative:

Takeoff clearance was given to our aircraft for runway 19, referencing a light twin (low wing) departing on runway 10. Tower directed us to maintain visibility on the twin, said he would be departing to the southwest, and further advised there was traffic on short final for our runway. As we began our roll the twin was beginning a slow turn to the right, beyond the runway intersection and to the left of our takeoff path. As we became airborne the twin appeared to be paralleling our flight path to the left. I made a slight right turn for sep, at which time the twin began a shallow turn to the right, across our flight path. I made a turn to the left, positive but not excessive, to pass behind the twin. We were approximately co-altitude at the time. We were switching to departure control at the time, who seemed concerned that we had the traffic in sight. Contributing factors include: 1) simultaneous takeoffs on perpendicular runways, 2) uncertainty on our crew's part as to the intention of the pilot of the twin, 3) traffic on short final behind us as we held in position for takeoff.

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Original NASA ASRS Text

Title: A DEP ACR LGT EXPERIENCES LOSS OF SEPARATION WITH ANOTHER DEP ACFT ON A CROSSING RWY DEP.

Narrative: TKOF CLRNC WAS GIVEN TO OUR ACFT FOR RWY 19, REFERENCING A LIGHT TWIN (LOW WING) DEPARTING ON RWY 10. TWR DIRECTED US TO MAINTAIN VIS ON THE TWIN, SAID HE WOULD BE DEPARTING TO THE SW, AND FURTHER ADVISED THERE WAS TFC ON SHORT FINAL FOR OUR RWY. AS WE BEGAN OUR ROLL THE TWIN WAS BEGINNING A SLOW TURN TO THE RIGHT, BEYOND THE RWY INTXN AND TO THE LEFT OF OUR TKOF PATH. AS WE BECAME AIRBORNE THE TWIN APPEARED TO BE PARALLELING OUR FLT PATH TO THE LEFT. I MADE A SLIGHT RIGHT TURN FOR SEP, AT WHICH TIME THE TWIN BEGAN A SHALLOW TURN TO THE RIGHT, ACROSS OUR FLT PATH. I MADE A TURN TO THE LEFT, POSITIVE BUT NOT EXCESSIVE, TO PASS BEHIND THE TWIN. WE WERE APPROX CO-ALT AT THE TIME. WE WERE SWITCHING TO DEP CTL AT THE TIME, WHO SEEMED CONCERNED THAT WE HAD THE TFC IN SIGHT. CONTRIBUTING FACTORS INCLUDE: 1) SIMULTANEOUS TKOFS ON PERPENDICULAR RWYS, 2) UNCERTAINTY ON OUR CREW'S PART AS TO THE INTENTION OF THE PLT OF THE TWIN, 3) TFC ON SHORT FINAL BEHIND US AS WE HELD IN POS FOR TKOF.

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.