Embraer Jet Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Human-Machine Interface
Aircraft Equipment Problem Less Severe; Deviation - Altitude Overshoot; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued Advisory / Alert; Flight Crew Returned To Clearance
Aircraft
On the Milton Four arrival we were given a crossing restriction of LIZZI at 11;000. We were also given a clearance to hold at LIZZI as published. Upon arrival at LIZZI the autopilot began to enter the hold but continued the VNAV descent past 11;000 FT. As pilot not flying I immediately verified that 11;000 was the altitude selected on the flight guidance panel and the MCDU. It was. As the pilot flying the First Officer pressed the TCS [Touch Controlwheel Steering] button and began a climb back to 11;000 FT. Around this time ATC queried us and I responded that we were correcting back to 11;000. Maximum altitude deviation was 250 FT. We turned once in the hold and continued the flight uneventfully. This event may have some relation to the OPS memo that deals with the ELDEE arrival into IAD. This event may expand the problems we have been having with the latest EPIC load. I am particularly concerned that the autopilot continued the descent past the altitude selected in the altitude selector. It seems the CAMI principle is as important as ever in making sure automation is doing what it is supposed to do.
The reporter states that he has not had any feedback from the company concerning this issue.
I confirmed the altitude and the FMS insertion with Captain per SOP. We started to descend via the VNAV mode as soon as the VTA slop guidance was activated.
Air Carrier Captain describes an altitude deviation while entering holding at LIZZI. With 11;000 set in the flight guidance panel and the autopilot engaged; the aircraft continued the VNAV descent. The deviation is quickly detected and corrected using the TCS button.