Challenger 300
Flight Crew Air Transport Pilot (ATP)
Situational Awareness; Distraction
Aircraft Equipment Problem Less Severe; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented; Flight Crew Overcame Equipment Problem
Aircraft; Human Factors
We started a descent to 6000 ft and direct to MIBSO on the RNAV 29. We had not yet reached MIBSO when the airplane started screaming at us saying 'GEAR' ''GEAR' and flashing red. We could not silence the noise. Our passengers were getting worried. We were at around 7600 ft with the airspeed at 230 kts. My non-flying pilot got out the QRH but it was no help in this situation. The airplane thought it was on the ground with the gear up. The radio alt was reading 0. The weather was clear and we could see the runway. We were cleared for the approach by ATC. My FO scrolled in 3000 ft into the alt selector. I assumed that 3000 ft was the next alt on the approach because the FO had the approach plate in front of him and we had briefed it was going to be a visual backed by this approach. I did not query his decision. I was busy descending and distracted by the gear warning system. Also I was thinking that once we start leveling off this gear issue might right itself and I would have better understanding of this issue. Such as slow down and drop the gear. So; when we did start to level off; sure enough the airplane realized it was flying and went back to normal. At that time ATC contacted us and informed us we were outside radar coverage and too low. We told ATC we were in the clear and could see the rwy. ATC then cleared us for a visual. No further action required. Lots of different situations happening at the same time. Plus it was VFR. We should have leveled off at 6000 ft and asked ATC for some delay vectors while we worked our problem instead of continuing on the approach. I think maybe because we could see the runway and I did not feel worried about the gear not being available to us; I thought it ok to continue on the approach. The problem was; we were just outside of MIBSO (5 mile or less). I talked with the FO after this situation and he thought we had already passed MIBSO. Had we already had been passed it would have been correct because we had been cleared for the approach. We should have leveled off at 6000 ft and asked ATC for some delay vectors while we worked our problem instead of continuing on the approach.
[Report narrative contained no additional information.]
CL-300 flight crew reported receiving a low altitude alert while distracted by a gear warning horn associated with an air-ground disagreement.