IAI1125 (Astra)
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor
Flight Crew Last 90 Days 36; Flight Crew Total 5500; Flight Crew Type 1100
Situational Awareness
Deviation - Altitude Crossing Restriction Not Met; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented
Aircraft; Human Factors
We were on an IFR flight to EWR and assigned the PHLBO3 arrival. We were given instructions to descend via the arrival and proceeded to do so. Upon reaching the crossing restriction altitude for the SOMTO Intersection; we leveled off approximately 5 miles prior to the intersection. At this time the Captain; the pilot flying; asked me to give him the Class B airspace information. I proceeded to evaluate the Class B airspace chart for EWR and when I looked up I noticed something did not look right. After a short evaluation of our location; I determined that we had passed our step down point to cross the DYLAN Intersection at 8;000 FT and advised the Captain to descend to 8;000 FT MSL. At this time; we were told top contact New York Center and the Controller realized we were at 10;800 FT. He instructed us to descend to 8;000 and turn right to a 120 heading. We were then turned back on course and handed off to New York. The Captain said he thought we had met all of the crossing restrictions since the VNAV glide slope had gone away after we passed the SOMTO Intersection. We were never given a TCAS alert and no aircraft was seen by the crew. I believe the concern for the Class B airspace and the busy airspace caused a loss of situational awareness by the flying pilot. While I was distracted by the task asked of me; I could have reminded the Captain of the crossing restriction before looking into his request. The crew was trying to insure the utmost safety and abide by all regulations. The timing of the planning was maybe at the wrong time and could have contributed to the deviation.
IA1125 First Officer reports the Captain missing the crossing restriction at DYLAN on the PHLBO3 RNAV arrival to EWR while the First Officer is evaluating the Class B airspace.  ATC issues vectors.