B737 Next Generation Undifferentiated
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Type 2330.47
Situational Awareness
Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Human Factors
While on the DRLLR5 arrival into Houston we were given the RNAV RNP runway 26R. When we entered the approach into the FMC we failed to close the discontinuity up between the arrival and the approach. When we were supposed to start the turn over DRKAR we continued straight out on the 087 heading per the DRLLR5 arrival with the autopilot on. Just after passing the DRKAR fix we disconnected the autopilot and started the turn to get back onto the approach. Shortly after commencing the turn the Approach Controller queried us to make sure we were turning onto the approach. We told him we were in the turn and got back on to the course just after passing DRKAR and continued in without any further incident. ATC did not query us again and we landed with no other issues.
We were coming in on the DRLLR 5 arrival linked up to the RNAV RNP Y 26R. We had initially planned for the ILS 26L...not the default runway which would have been 26R...the First Officer (FO) was just wishfully thinking. When we checked on we were told to expect the RNAV RNP so the FO loaded it into the box. We had previously checked all altitudes and waypoints on the previous arrival and approach combination. But we failed to do it when we changed approaches. It left a discontinuity between the end of the arrival and the approach transition at SKLER. SKLER and DRKAR are very close together and we had just passed SKLER and I looked down and realized the DRKAR was white and not magenta...IOW it was not the next active waypoint and it should have been. I hurried and tried to jam it into the box but was too late. The autopilot; under our command (or lack thereof); went straight on the vector portion and did not turn at DRKAR. The FO disconnected the autopilot and turned onto the course manually. We did not go more than a mile past DRKAR and while turning; ATC did query us. We got back on the course line and continued with the approach. It was VMC so not of much consequence. It could have been a little more sporting IMC and in more challenging conditions.
B737NG flight crew reported a track deviation occurred on the RNAV RNP arrival into IAH after failing to close a discontinuity in the FMC.