Narrative:

We were given a radar vector for the xx ILS with a clearance to expect zzzzz. Due to weather in the area I requested deviation from the radar vector. When sequencing the FMS; I could not find zzzzz on the FMS ILS DME xx. I found ZZZZZ1 on the FMS ILS xx. The fixes are similar; but not the same. I verified the fix to expect with ATC and was again given zzzzz. Thinking I made an error loading the FMS; I reviewed a few approaches in the FMS. Still I could not find zzzzz. Around this time; I heard the autopilot disengage. I asked; 'did you disengage the autopilot.' the answer was no. I immediately thought the yaw damp disengaged. I noticed the airspeed was low. I stated something like; 'your airspeed is slow.' [first officer] responded; and added full thrust. Although the airspeed was increasing we lost altitude. The airspeed was passing through 200 knots and I mentioned to climb to 12000 feet. The airspeed continued to increase but no change in pitch. I took the controls to return to 12000 feet. ATC gave us a vector to join the approach. I realize I spent too much time fiddling around with the FMS with my head down away from a scan.in the FMS ILS xx; zzzzz does not exist. Zzzzz only exist in the FMS RNAV xx.

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Original NASA ASRS Text

Title: CRJ-900 Captain reported becoming distracted with a confusing clearance then noticing the autopilot disconnected due to low airspeed.

Narrative: We were given a radar vector for the XX ILS with a clearance to expect ZZZZZ. Due to weather in the area I requested deviation from the radar vector. When sequencing the FMS; I could not find ZZZZZ on the FMS ILS DME XX. I found ZZZZZ1 on the FMS ILS XX. The fixes are similar; but not the same. I verified the fix to expect with ATC and was again given ZZZZZ. Thinking I made an error loading the FMS; I reviewed a few approaches in the FMS. Still I could not find ZZZZZ. Around this time; I heard the autopilot disengage. I asked; 'did you disengage the autopilot.' The answer was no. I immediately thought the yaw damp disengaged. I noticed the airspeed was low. I stated something like; 'your airspeed is slow.' [First Officer] responded; and added full thrust. Although the airspeed was increasing we lost altitude. The airspeed was passing through 200 knots and I mentioned to climb to 12000 feet. The airspeed continued to increase but no change in pitch. I took the controls to return to 12000 feet. ATC gave us a vector to join the approach. I realize I spent too much time fiddling around with the FMS with my head down away from a scan.In the FMS ILS XX; ZZZZZ does not exist. ZZZZZ only exist in the FMS RNAV XX.

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.