Aero Astra

Before takeoff, a pilot of XA-KUT was briefed that the Houston Hobby (HOU) weather was IFR with '. . . Indefinite ceiling zero sky obscured visibility's 1/16 of a mile and fog . . .' He was also advised IFR conditions were forecast until 0900 cst, gradually improving to marginal VFR by 1100 cst with 1,000 feet broken, 5 miles visibility and fog. The flight took off at 0900 cst. At HOU, arrival was delayed due to weather. The crew requested an ILS approach, with intentions of diverting if a missed approach was made. The RVR was variable. After being cleared for an ILS runway 04 approach, the pilot was advised the RVR had dropped to 1,400 feet. After changing to tower frequency, the flight was cleared to land and was told again the RVR was 1,400 feet. When the aircraft was on final approach, the pilots were advised of a low altitude alert. However, the aircraft continued below the decision height (dh), hit a 70 feet power line (approximately 6,500 feet short of the runway) and crashed. No preimpact malfunction of the aircraft or its systems was found. The ILS was flight checked, but only a minor discrepancy (concerning the outer marker width) was noted. The dh was 200 feet agl, minimum RVR for the approach was 2,400 feet. The copilot was killed and seven other occupants were injured, three seriously.