Date: 202105
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: Challenger CL604
Operator: Air Taxi
Operating under: Part 135
Flight plan: IFR
Mission: Ferry / Re-Positioning; Other Reposition flight
Flight phase: Initial Approach
Airspace: Class B ZZZ
Aircraft component: Navigational Equipment and Processing
Component problem: Malfunctioning
Reporter organization: Air Taxi
Reporter function: First Officer; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor; Flight Crew Instrument; Flight Crew Multiengine
Human factors: Confusion; Distraction; Human-Machine Interface; Situational Awareness; Training / Qualification; Workload
Anomaly: Aircraft Equipment Problem Less Severe; Deviation - Altitude Crossing Restriction Not Met; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Overcame Equipment Problem; Flight Crew Overrode Automation
Contributing factors: Aircraft; Human Factors
Primary problem: Human Factors

Narrative: While serving as PF (Pilot Flying) into ZZZ on the ZZZZZ arrival; I was flying the aircraft with autopilot; autothrottle; and VNAV. We had programmed the STAR along with a transition to the ILS XXR into ZZZ and reviewed all the fixes and block altitudes on the Pro Line Fusion MFD screen. The aircraft flew the STAR without incident from FL280 all the way down to about 13000. The VNAV and autothrottle were working. I became distracted when the autothrottle failed to reduce 'FMS speed' for ZZZZZ1 to 250. I manually selected 250 and slowed. I reactivated the FMS speed function and verbally announced that we would monitor the speed and to make sure it made the next speed slowdown proactively at ZZZZZ2. What I failed to properly notice is the VNAV set a floor altitude of 13000 and leveled off. I did not think much of it since the next fix was an 'at or above' 9000 so I thought it was a level-off in lieu of an overly shallow descent.While being distracted in over-monitoring the FMS speed reduction; we got caught in an undesirable aircraft state. To make the alt window at ZZZZZ3; 9000-8000; I manually selected VS and adjusted the descent rate and flight spoilers in order to make that fix's alt window. I believe it was too close to notice if we made it or not and we did not seek relief with ATC since the Captain seemed unsure how to query ATC since he too was interested in watching the VNAV and FMS speed since he had little time on this Pro Line Fusion avionic suite. I flew the remaining alt windows in VS mode since that higher level of automation was not trustworthy or compatible with my state at that time. Later in the arrival; before ZZZZZ4; ATC gave us relief off the arrival and gave a descent to 3000. I dialed 3000 into the FGCP and the Captain confirmed the ALT. Continued down in VS. Since the previous UAS - Undesired Aircraft State - was around 10000; it impeded on the 'in-range check' being completed. We were at about 6500 when the in-range check was started and it distracted us from noticing the aircraft was still in VNAV and had captured the floor of the arrival; 6000; and did not continue [the] descent to 3000. ATC would query us shortly and again I would notice that the aircraft in a UAS. I noticed VNAV still active and disabled it; and continued down. We intercepted the approach and landed without further incident.In hindsight and a word of caution; this is the first avionics suite I have seen where altitudes on a STAR can be superseded by altitudes on an approach. In this example; the ZZZZZ STAR with the ILS XXR ZZZZZ5 transition. There was a discontinuity between ZZZZZ6 and ZZZZZ5. I want to know why in what world should VNAV look ahead of a discontinuity and block the VNAV windows on the STAR. All the stepdowns on the ILS XXR were there for reference as there no way knowing how far in the downwind ATC would take you before a base turn. I don't have a lot of VNAV-capable aircraft experience and I see tremendous issues with not being properly trained in how the aircraft will respond based on what is programmed into the FMS. In general; the avionics differentiation training was lacking and laughable and the differences from the standard avionics in the CL604. It seems half-finished and very retrofit. Having to train on-the-line with the suite to new crew members is frustrating at best and dangerous at worst. I will continue to step up and down levels of automation as my comfort and knowledge adjusts and will try to look for any potential red flags in FMS programming beyond the basic comparing to the approach plate.




Synopsis: CL604 First Officer reported missing a crossing restriction during descent.