sentence1: The Santa Barbara Airlines plane took off just before dusk from the city of Mérida en route to Simón Bolívar International Airport outside the capital city of Caracas. Noel Marquez, director of Venezuela's emergency management agency in Mérida, said the plane has failed to contact control towers. Civil Defense chief General Antonio Rivero told reporters that it is unknown whether or not the plane crashed or is simply missing.
sentence2: A plane with 46 passengers has not contacted control towers.