MD-88
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Engineer; Flight Crew Flight Instructor; Flight Crew Instrument
Flight Crew Last 90 Days 200; Flight Crew Total 15000; Flight Crew Type 2800
Human-Machine Interface; Communication Breakdown; Distraction; Situational Awareness
Deviation - Altitude Crossing Restriction Not Met; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Aircraft; Weather; Human Factors
The First Officer was the pilot flying the RAVNN RNAV STAR into BWI. The STAR requires the aircraft to cross OTT at 9;000 MSL. The First Officer was using VNAV to fly the aircraft. However; we had over 100 KTS of tailwind and VNAV was having difficulty calculating the descent rate needed to meet the crossing restriction. I was performing the descent and arrival procedures and was momentarily distracted from monitoring the aircraft's progress. When I did notice our higher than normal groundspeed I directed the First Officer to increase his descent rate in order to comply with the restriction. He elected to use vertical speed at first but I soon directed him to disconnect all aircraft automation and hand fly the aircraft to try to meet the restriction. He increased the descent rate in an attempt to comply but was unsuccessful. The aircraft crossed OTT at approximately 9;600 MSL. There were no aircraft or terrain conflicts. ATC did not comment and we continued to BWI and landed uneventfully. If the First Officer had increased the rate of descent we would have made the restriction. If I had asked for relief on the restriction we would not have had to submit this report.
An MD88 was unable to comply with a 9;000 MSL crossing restriction at OTT on the RAVNN RNAV STAR to BWI. 100 KTS tailwinds and a tardy recognition of the need to abandon autoflight in order to comply contributed to the deviation.