Super King Air 200
Flight Crew Flight Instructor; Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Last 90 Days 53; Flight Crew Total 16200; Flight Crew Type 5500
Human-Machine Interface; Situational Awareness
Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Human Factors; Aircraft
When conducting the ILS 20 approach to CHA; I was vectored to final by Chattanooga approach control. I was given a heading and told to maintain 3000 until passing the Daisy outer marker (IAF). I was flying using the autopilot and selected approach mode on the autopilot. The airplane started descent with the Glide slope indicator showing slightly below the glide slope. I continued to descend until passing Hixon OM; the final approach fix. I realized that I was below the crossing altitude of 2100 feet and stopped my descent. Then shortly thereafter I was told by approach control that they had received a low altitude warning. Thereafter; I broke out of the clouds and landed at CHA.
King air 200 Captain experiences an early descent on the glideslope using the autopilot to fly a coupled approach. At the FAF the low condition is detected by the reporter who begins correcting at the same a low altitude alert is received from the Tower. A normal landing ensues.