B737 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Last 90 Days 200; Flight Crew Type 3000
Confusion; Human-Machine Interface
Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued New Clearance
Human Factors
At some point soon after leaving our cruise altitude; we were given a 'good rate of descent' request and we were still a good distance from the TOD (Top of Descent). As a result of this request; I (the Pilot Flying) selected V/S (Vertical Speed) and dialed in a descent rate of 2;500 fpm. Where were assigned an altitude lower than FL 270. During the descent and around FL 280; we received a 'descend via the TBARR ONE'. I re-cruised the FMC for FL 270 as we were a good distance from the restriction at BBRRO at FL 270; but I did not arm VNAV. I was watching as we were approaching FL 270 but it did not stop at FL 270 because I was still in V/S. We immediately told ATC and he told us to just make the next restriction on the STAR. I should have engaged VNAV and the Pilot Monitoring should have caught that I neglected to do so. ATC should limit giving a 'descend via' clearance when you are so close in altitude to an altitude restriction.
First officer reported that while assigned a descent below FL270; they were reassigned to descend via the TBARR STAR too late to arrest the descent.