Regional Jet 900 (CRJ900)
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 3
Situational Awareness
ATC Issue All Types; Deviation - Altitude Undershoot; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Provided Assistance; Flight Crew Requested ATC Assistance / Clarification
Human Factors
Aircraft X checked onto departure assigned the MNZNO3 departure. Departure assigned Aircraft X to climb via the SID and Aircraft X read this back. While on the SID about a mile south of YUGLU; where aircraft need to begin their climb; Aircraft X was confused of the climb instructions and said 'We just want to verify that we're supposed to maintain 90?' Departure corrected their misinterpretation and told them 'Top altitude FL200'. They then understood immediately that they needed to climb fast to meet the climb requirements to meet the MVA as they climbed 2;300 feet in about six miles all within one minute. Had their rate of climb been slow; or their confusion more delayed; they would not have made the MVA and Departure would have been required to vector Aircraft X off the SID to climb above the MVA. This is a safety problem if Departure were busy and did not notice the aircraft delaying their climb; or leveling off at 90 before turning to the east into the MVA. It takes one minute from the fix YUGLU; where they're supposed to begin their climb; before reaching MNZNO; where they begin their turn to the east into an MVA of 113. If Departure is expecting pilots to comply with 'Climb Via' instructions; and they read this back; their scan may not be focused on the departing aircraft's altitude; especially with a high workload.Aircraft on clearance should be instructed to 'Climb via Sid' with no altitude restrictions; and if approach needs an altitude restriction this will be given upon aircraft check in.-OR-All pilots need to be on the same page that when departure clears an aircraft to 'Climb via SID' this deletes the clearance delivery restriction previously given.
ABQ Tracon Controller reported an air carrier pilot was confused by a climb via clearance and delayed climbing.