Narrative:

I was first officer/pilot monitoring; captain was pilot flying. We were cleared to 'descend via the PHLBO3RNAV arrival.' properly briefed by captain; reviewed by first officer/pilot monitoring. During descent first officer/pilot monitoring turned off screen of efb to preserve battery life; on assumption that briefing was done properly; this was a 'routine operation conducted numerous times in recent past;' info was duplicated in FMS; and captain was also a more experienced pilot who had a decade more experience than first officer and 'had the procedure memorized.' altitude set to 11;000 [feet] for somto; no issues. Passing somto; captain/pilot flying set altitude to 7;000 [feet] (as opposed to correct 8;000 [feet]) for dylin; and announced '7;000 set.' I; as first officer/pilot monitoring; responded'7000 set' and confirmed setting; without noticing error and thus taking corrective action. We descended to 7000. No comment from ATC; who handed us off to next controller. It was that controller who questioned us about the 7;000 feet altitude; advised that it was 'no big deal' while pointing out we were supposed to be at 8;000 [feet]; and then had us continue descending to 5;000 feet to continue approach to newark 4R. Captain and first officer debriefed that neither one of us caught the obvious error; and agreed we had been 'conditioned' to expect 7;000 feet from the much more frequently used (by us at least) crank at 7;000 feet of the FLOSI3RNAV arrival from the north. 1;000 feet lower than expected at that portion of the arrival procedure and during ATC hand-off. Do not try to stretch battery life of efb at the expense of being able to properly monitor the situation. Read the procedure every time in detail; even if it is one which you think you are familiar with.

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Original NASA ASRS Text

Title: Air carrier flight crew using EFB charts turned off EFB to conserve battery life. During STAR arrival; an altitude was missed and ATC notified the crew of the deviation.

Narrative: I was First Officer/Pilot Monitoring; Captain was Pilot Flying. We were cleared to 'Descend via the PHLBO3RNAV Arrival.' Properly briefed by Captain; reviewed by First Officer/Pilot Monitoring. During descent First Officer/Pilot Monitoring turned off screen of EFB to preserve battery life; on assumption that briefing was done properly; this was a 'Routine operation conducted numerous times in recent past;' info was duplicated in FMS; and Captain was also a more experienced pilot who had a decade more experience than First Officer and 'had the procedure memorized.' Altitude set to 11;000 [feet] for SOMTO; no issues. Passing SOMTO; Captain/Pilot Flying set altitude to 7;000 [feet] (as opposed to correct 8;000 [feet]) for DYLIN; and announced '7;000 set.' I; as First Officer/Pilot Monitoring; responded'7000 SET' and confirmed setting; without noticing error and thus taking corrective action. We descended to 7000. No comment from ATC; who handed us off to next Controller. It was THAT Controller who questioned us about the 7;000 feet altitude; advised that it was 'no big deal' while pointing out we were supposed to be at 8;000 [feet]; and then had us continue descending to 5;000 feet to continue approach to Newark 4R. Captain and First Officer debriefed that neither one of us caught the obvious error; and agreed we had been 'conditioned' to expect 7;000 feet from the much more frequently used (by us at least) CRANK at 7;000 feet of the FLOSI3RNAV Arrival from the north. 1;000 feet lower than expected at that portion of the arrival procedure and during ATC hand-off. Do NOT try to stretch battery life of EFB at the expense of being able to properly monitor the situation. Read the procedure EVERY TIME IN DETAIL; even if it is one which you THINK you are familiar with.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.