Narrative:

After landing at hpn, we obtained a clearance to hvn from the tower. Part of our clearance was to contact ny departure airborne. Having read through our operations manual and received our clearance, we determined that we were released. Once we were airborne and contacted departure, we were informed that we took off without a release. The rest of the flight was uneventful. Supplemental information from acn 313730: white plains issued us a clearance and told us to contact ny approach airborne. We did tell approach control we misunderstood the tower.

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Original NASA ASRS Text

Title: AN ACR MLG TOOK OFF FROM A NON TWR ARPT TWR CLOSED WITH NO DEP RELEASE ON AN IFR FLT PLAN.

Narrative: AFTER LNDG AT HPN, WE OBTAINED A CLRNC TO HVN FROM THE TWR. PART OF OUR CLRNC WAS TO CONTACT NY DEP AIRBORNE. HAVING READ THROUGH OUR OPS MANUAL AND RECEIVED OUR CLRNC, WE DETERMINED THAT WE WERE RELEASED. ONCE WE WERE AIRBORNE AND CONTACTED DEP, WE WERE INFORMED THAT WE TOOK OFF WITHOUT A RELEASE. THE REST OF THE FLT WAS UNEVENTFUL. SUPPLEMENTAL INFO FROM ACN 313730: WHITE PLAINS ISSUED US A CLRNC AND TOLD US TO CONTACT NY APCH AIRBORNE. WE DID TELL APCH CTL WE MISUNDERSTOOD THE TWR.

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.