Super King Air 350
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor; Flight Crew Instrument
Flight Crew Last 90 Days 300; Flight Crew Total 3000; Flight Crew Type 380
Situational Awareness
Deviation - Altitude Excursion From Assigned Altitude; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Aircraft; Human Factors
We were flying into HRL repositioning for our passengers. We were cleared the ILS 17R approach. The Autopilot (AP) was flying. The chart indicated that we could descend to 1;400 feet 10 miles from the FAF. The FMS had the correct altitude and we put the AP controller into VNAV mode where it descended and captured the 1;400 feet altitude. It was a little late leveling off and we got to maybe 1;340 at the lowest. It then leveled off at 1;400 feet. The Tower Controller told us that we had a low level alert which showed us at 1;300 feet. The autopilot was already correcting the altitude and no further action was necessary. We got the runway in sight and were cleared to a visual approach for the parallel Runway 17L and landed without further incident.
BE350 Captain reports getting 60 feet low prior to the FAF at HRL with the autopilot flying; which results in a low altitude alert from the Tower. The autopilot corrects back to 1;400 feet and the approach is continued to landing.