Crj first officer reported receiving a low altitude alert from ATC on approach to bmi. They realized...

Narrative:

I was the first officer and pilot flying for the visual approach to runway 20 at bmi. We were cleared for the visual and I descended with the glideslope as a backup. Several miles out on the approach; the aircraft looked low and I immediately clicked off the autopilot and corrected the airplane's approach path. As I corrected the aircraft's flightpath; ATC called and said they had received an altitude low warning on our aircraft. We acknowledged and continued the approach and landed safely. The captain informed ATC that the glideslope was giving incorrect information and ATC informed us that the glideslope was out of service. At this point we realized that the NOTAM for an inactive glideslope was still active and we had briefed that the NOTAM would not affect our approach. This event was caused by a misinterpretation of notams on the release. This event could have been avoided by thoroughly briefing the notams as a crew and not relying on a system that was out of service.

Original NASA ASRS Text

Title: CRJ First Officer reported receiving a low altitude alert from ATC on approach to BMI. They realized they were following a glide slope that was NOTAMed out of service.

Narrative: I was the First Officer and Pilot Flying for the visual approach to Runway 20 at BMI. We were cleared for the visual and I descended with the glideslope as a backup. Several miles out on the approach; the aircraft looked low and I immediately clicked off the autopilot and corrected the airplane's approach path. As I corrected the aircraft's flightpath; ATC called and said they had received an altitude low warning on our aircraft. We acknowledged and continued the approach and landed safely. The Captain informed ATC that the glideslope was giving incorrect information and ATC informed us that the glideslope was out of service. At this point we realized that the NOTAM for an inactive glideslope was still active and we had briefed that the NOTAM would not affect our approach. This event was caused by a misinterpretation of NOTAMs on the release. This event could have been avoided by thoroughly briefing the NOTAMs as a crew and not relying on a system that was out of service.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	1568916
Time
Date	201808
Local Time Of Day	1201-1800
Place
Locale Reference	BMI.Airport
State Reference	IL
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Regional Jet CL65 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Flight Plan	IFR
Person 1
Function	Pilot Flying First Officer
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Deviation - Procedural Published Material / Policy Inflight Event / Encounter CFTT / CFIT

Crj first officer reported receiving a low altitude alert from ATC on approach to bmi. They realized they were following a glide slope that was notamed out of service.