Small Transport
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor; Flight Crew Instrument
Flight Crew Last 90 Days 150; Flight Crew Total 6000; Flight Crew Type 2000
Situational Awareness; Confusion
Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented; Flight Crew FLC complied w / Automation / Advisory
ATC Equipment / Nav Facility / Buildings; Human Factors; Weather
We were on vectors for an ILS approach. When given turn to intercept LOC; ATC informed us that the GS was now Out of Service (OTS) and we were now cleared for the LOC approach instead. In hind sight; at this point I should have discontinued the approach and gone around. This would have allowed my crew to properly brief the LOC approach. I did not do this. Instead; we continued the approach thinking we would be able to easily identify all the step down altitudes. We crossed the first fix at 2;300 feet and then descended all the way to 1;000 feet MDA. By doing this; we missed the 1;640 feet mandatory level-off at the second fix. We broke out of the clouds at 1;200 feet just as we received a low altitude alert from Tower. We were then able to see that we were too low and climbed back up to 1;500 feet; which was now clear of clouds; until we were back on a more appropriate visual glide path.
Glideslope failed during ILS approach. Flight crew converted to LOC only approach procedures; but missed a crossing altitude restriction. Tower received a low altitude alert.