MD-11
Situational Awareness; Distraction; Human-Machine Interface; Communication Breakdown
ATC Issue All Types; Deviation - Altitude Crossing Restriction Not Met; Deviation - Altitude Undershoot; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Weather / Turbulence
Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification
Chart Or Publication; Procedure; Weather
We were flying the PAATS RNAV STAR at an assigned airspeed of 280 KTS. ATC then told us to cross HEDGE at 15;000 FT. The Captain selected level change (idle) and full speed brakes. The tailwinds were in excess of 100 KTS at that point and it looked like we would be high at HEDGE. The aircraft in front of us reported they would not be able to make the restriction due to the tailwind. The Controller said 'just do the best you can.' Then the aircraft behind us reported they would not be able to make the restriction; and the Controller said; again; 'Just do the best you can.' It didn't seem necessary to add to the already congested radios that we would also probably not make the restriction. We crossed HEDGE approximately 1;000 FT high. The Controller made no mention of it and we continued the remainder of the approach and landing without incident. Earlier in the arrival we saw that we were going to be tight making the expected altitudes on the STAR and requested a descent. Instead of a descent clearance we got a frequency change and by the time I was able to check in on the new frequency we were well above the descent profile. The new Controller gave us a descent with a speed restriction (280 KTS) but no altitude constraints. When the 15;000 FT crossing restriction at HEDGE was assigned we were already high on the descent profile; and that coupled with the airspeed restriction and the excessive tailwind; made it a clearance that could not be complied with.ATC must issue descent clearances earlier when strong tailwinds are present. Also; on my part; I need to clearly communicate to ATC; as soon as it is evident; when we cannot comply with a clearance. I was proactive in trying to get a clearance to start our descent but did not communicate our inability to comply with the subsequent clearance.
[No additional substantive information was included in the secondary narrative.]
High tailwinds and an ATC airspeed restriction caused the flight crew of an MD-11 to be unable to comply with the crossing restrictions on the PAATS RNAV STAR to PHL.