Flight Crew Air Transport Pilot (ATP)
Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance
Flight Crew Landed As Precaution; Flight Crew Returned To Departure Airport; Flight Crew Returned To Clearance; Flight Crew Became Reoriented; General Maintenance Action
Aircraft; Human Factors
Right red gear unsafe light illuminated; as well as all three amber gear door lights and gear in transit lights upon raising the landing gear after takeoff. We also noticed a loud grinding noise coming from underneath the flight deck. This resulted in our flight returning to [departure airport]. Mechanically to be determined. Aircraft was subsequently ferried to a maintenance base to determine the cause of the indications. After the gear indications were noticed; ATC was notified (emergency was not declared); as well as the flight attendant; who was asked to visually inspect the landing gear. We ran the appropriate checklist; which led to alternate gear extension; and notified ops of our situation and asked them to notify dispatch. The passengers were also notified that we would be returning to [departure airport]. At this point; the Captain noted that we had drifted from our assigned altitude of 4;000 ft down to 3;300 feet. This was immediately corrected and ATC was notified. The Captain remarked that he thought the autopilot was engaged; when it in fact was not. After we landed; ATC was called via telephone to discuss the situation that had occurred. The controller replied that all traffic was cleared from our area to accompany us while we ran our checklists; and that the altitude deviation was not an issue. He also mentioned that we were well above his MVA. From this event; I was reminded of the importance of always monitoring aircraft automation while running checklists and emergency checklists. What the pilot perceives the automation to be doing and what the automation is actually doing can be different; if careful attention is not paid. As a crew; we debriefed the event and discussed what was done well; and what could have been improved upon.
Dash-8 First Officer reported returning to the departure airport after experiencing abnormal landing gear indications after gear retraction.