Narrative:

Small transport X reported on oac (sector 79) frequency at approximately XX00Z at FL140 barow estimate XX17Z. Oac had no flight plan on this aircraft. Small transport X advised he received IFR clearance from merida via cun A766 gls hou. Small transport X was an small transport speed 200 KTS. The radar associate controller called merida who advised they knew the aircraft and verified the flight plan. The aircraft was advised of an international NOTAM that prohibits aircraft at or below FL180 without HF equipment in oac airspace (then cleared to hou). The merida supervisor advised the houston supervisor they would call us back, but never did. This is a very common occurrence.

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Original NASA ASRS Text

Title: IFR ACFT ENTERS CTLR AIRSPACE WITHOUT A FLT PLAN OR PRIOR HDOF FROM ADJACENT FOREIGN ATC FACILITY.

Narrative: SMT X RPTED ON OAC (SECTOR 79) FREQ AT APPROX XX00Z AT FL140 BAROW ESTIMATE XX17Z. OAC HAD NO FLT PLAN ON THIS ACFT. SMT X ADVISED HE RECEIVED IFR CLRNC FROM MERIDA VIA CUN A766 GLS HOU. SMT X WAS AN SMT SPD 200 KTS. THE RADAR ASSOCIATE CTLR CALLED MERIDA WHO ADVISED THEY KNEW THE ACFT AND VERIFIED THE FLT PLAN. THE ACFT WAS ADVISED OF AN INTL NOTAM THAT PROHIBITS ACFT AT OR BELOW FL180 WITHOUT HF EQUIP IN OAC AIRSPACE (THEN CLRED TO HOU). THE MERIDA SUPVR ADVISED THE HOUSTON SUPVR THEY WOULD CALL US BACK, BUT NEVER DID. THIS IS A VERY COMMON OCCURRENCE.

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.