Flight Crew Air Transport Pilot (ATP)
Situational Awareness; Human-Machine Interface; Confusion
ATC Issue All Types; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued New Clearance; Air Traffic Control Issued Advisory / Alert; Flight Crew Returned To Clearance
Human Factors; Chart Or Publication
I was pilot not flying; Captain was pilot flying. We were originally cleared to MCO via the PIGLT4 RNAV STAR; direct [to] OCF [thence via the OCF] transition. Shortly thereafter; we were re-cleared direct OTK and remainder of PIGLT 4 arrival. After about 2-3 minutes; the Controller inquired if we were direct to OTK. Initially I replied we were but after review of our course; it did not quite make sense. The Captain reprogrammed direct to OTK which required a 15-20 degree heading change and resulted with OTK as the only active waypoint. We had followed the normal verification process before the original execution; however; somehow the selection of several abeam points between our present position and OTK resulted in a course error that went unnoticed.Sometimes the selection of abeam points are so close together; it can cloud the actual 'cleared to' fix. A more thorough and careful review and verification on my part is essential!
Next time I would expand the map to a larger scale to verify the new course change in addition to checking the course in our normal procedures.
When ATC changed their clearance from direct to OCF; cleared for the PIGLT RNAV STAR to cleared to OTK for the STAR the flight crew of a B737-800 failed to confirm their reprogramming of the FMC and a track deviation; caught by ATC; resulted.