EMB ERJ 145 ER/LR
Flight Crew Air Transport Pilot (ATP)
Workload; Situational Awareness; Human-Machine Interface
Aircraft Equipment Problem Less Severe; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance
Flight Crew Returned To Clearance
Chart Or Publication; Human Factors
Just prior to crossing MMAXX intersection on the KIDDZ RNAV arrival [to HOU] descent was initiated to the next crossing restriction slightly prematurely. The non flying pilot noted the deviation and the altitude was promptly corrected.This is a new STAR. It is very complex; and requires both crewmembers undivided attention during a phase of flight where other flight crew duties are required; i.e. checklist accomplishment; approach briefing etc.Since this new STAR is very complex and requires both crewmembers undivided attention during a phase of flight that requires that attention be given to other required duties during this phase of flight; I would suggest that those other duties be accomplished as early as possible so that both crewmembers can refocus undivided attention to this complex arrival procedure.
We were cleared by ATC to descend via the KIDDZ1 arrival.  A few miles prior to MMAXX the pilot flying began a slow descent and I alerted him to the fact we should be at FL240 until MMAXX. He acknowledged the error and we reached FL240 at about MMAX and then continued the arrival with no other issues.
When cleared to descend via the KIDDZ RNAV STAR the pilot flying began a descent from FL240 prior to MMAXX which must be crossed at or above FL240.  The pilot not flying of the ERJ promptly advised the descent was premature and they corrected.  Both reporters addressed their concerns about the complexity of the arrival and the high workload it incurs during a phase of flight that includes conflicting demands on the flight crew's attention.