B737 Next Generation Undifferentiated
Flight Crew Air Transport Pilot (ATP)
Flight Crew Type 394
Communication Breakdown
ATC Issue All Types; Deviation - Altitude Crossing Restriction Not Met; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued New Clearance
Chart Or Publication; Procedure
We were descending on the CREDE3 RNAV ARRIVAL into Denver. Per the ATIS received; we had loaded the Runway 16R transition into the FMS; briefed the arrival accordingly; and verified all crossing and speed restrictions were in the FMS. The aircraft was on the idle descent path; on speed at 280 knots; with VNAV engaged as we descended through approximately FL230. The next restriction on the arrival that we had to satisfy was to cross the POWDR waypoint between FL220 and 17;000 ft. The aircraft was on path; and was going to cross POWDR at about 20;500 ft. Denver Center then issued us a clearance to cross POWDR waypoint at 17;000 ft. This was entered into the FMC; and as expected; we were nearly 4000 ft above the new required descent path. In addition; the arrival dictates 280 knots in the descent; and to cross POWDR at 250 knots. Full speed brakes had a limited impact on our descent; and it was very obvious we had zero chance of making this crossing. We told ATC that we would be unable to make POWDR at 17;000 ft. The Controller responded 'Why not?' The Controller continued to sound somewhat exasperated (and less than professional) as he implied we had somehow messed up. Frequency congestion then followed which prevented us from explaining that we were set up to satisfy all crossings on the arrival per the chart. ATC did not give us altitude or airspeed relief; and instead vectored us off course prior to crossing POWDR. No restrictions were actually missed. The Controller's attitude and implication that we had somehow been at fault led us to submit this report. It should be noted that nowhere on the arrival chart does it mention that we should expect to cross POWDR at the very bottom of a 5000 ft block of altitude. Also; I have never received a clearance like this going into Denver; and the Captain did not anticipate this kind of clearance based on his extensive experience.The arrival procedure needs to reflect crossing restrictions that reflect the expectations of ATC. These things should NOT just be 'tribal knowledge'. We ended up landing on Runway 7; which I feel was the trigger for ATC to issue the early descent. However; we had no information to prompt us to consider crossing POWDR at the lowest listed crossing altitude. Additionally; Runway 7 was not listed as a runway in use on the ATIS; which was retrieved at about five minutes after the hour. As you know; Denver has a terrible habit of issuing four to five new ATIS broadcasts each hour; even on fair weather days. These new broadcasts are triggered by the frequent changes in runways in use (specifically adding and deleting runways 7/25 and 8/26) based on very short term traffic needs. While we know to seek additional ATIS updates because of Denver's runway changes; there is a point where we have to focus on flying the aircraft and not on scanning the ATIS every five minutes. There are no runway-specific crossing restrictions or transitions on the arrival. Likewise; ATC gave us no information to expect a lowest-possible crossing restriction. Denver needs to find a better way to communicate expectations to the pilots.
[Report narrative contained no additional information.]
B737 flight crew reported that while on the CREDE3 RNAV Arrival into DEN; ATC changed the clearance from the chart-depicted crossing at POWDR between FL220 and 17000 to at 17000 ft. The crew was unable to make that crossing restriction and the STAR's speed restrictions and were vectored off arrival as a result.