Black Line Edge Greater than an uneasy, unexplainable feeling. Divorcing itself from the runway at 2244, the Electra reached its assigned, 15,000-foot altitude 13 mins later, at 2300, retaining a 275-knot pace on its highly brief region to Dallas. After reporting its position over Leona, Texas, 5 mins later, it become instructed, "Request you now screen Fort Worth on a frequency of 120.8," which was recorded in the logbook as "Transmission completed, 2307."