Date: 201507
Location: ATL.Airport, GA
Flight conditions: Mixed
Weather elements / visibility: 8
Light: Daylight
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class B ATL
ATC / advisory: TRACON A80
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown; Confusion; Distraction; Workload
Second reporter function: Pilot Not Flying; Captain
Anomaly: ATC Issue All Types; Deviation - Altitude Undershoot; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew; Person Air Traffic Control
Result: Air Traffic Control Issued Advisory / Alert
Contributing factors: Aircraft; Weather; Procedure
Primary problem: Weather

Narrative: The Final Approach Controller in ATL was frustrated with our descent rate. We were inbound from the west on the WARRR1 RNAV Arrival; landing Runway 28. We were given the descent from 12;000 feet to 7;000 feet and did so in level (LVL) change (CHG) at 210 knots. Then there were two large buildups that we had to fly through; generating a period of moderate turbulence. After passing through this area of weather; we extended flaps to two. When we were handed off to the Final Controller; we were given a descent to 3;000 feet; our cue to be ready for the approach; so we extended flaps to five; still in LVL CHG at 210 knots. Shortly thereafter he called; frustrated with our descent rate. At 210 knots; the only thing left was to lower the landing gear; which we did while still on downwind. I know we need to descend quickly and I thought we were configuring appropriately. During the period of moderate turbulence; I believe our descent rate was reduced and situational awareness can be less in a cloud. I believe these were both contributing factors.


Second narrative: We then got a descent clearance; knowing we had to expedite; the FO selected Level Change on the MCP (we were slowed to 210 knots by ATC); then we entered another buildup with moderate turbulence and updrafts. The FO pushed the power up a little and I questioned that action. He stated he didn't want the aircraft to slow below 210 knots; I then explained that it wouldn't; the MCP would use pitch to maintain the airspeed. We exited the buildup and the turbulence; extended flaps to assist with the descent rate. The controller was not happy and yelled at us to descend faster. I responded that we were doing the best we could. We then extended the gear to get the aircraft down faster maintaining our assigned airspeed of 210 knots. We both understood the need for an expeditious descent on the arrival and were trying to accommodate the best we could. The weather and the aircraft type played a large role in our difficulty with getting descended faster. The older model aircraft are more speed restricted on the flaps; and the updrafts of the buildups compounded the situation. Without flaps the best descent rate is 1;000 FPM at 210 knots. With the history of spindle failures I am reluctant to maintain 210 knots with flaps extended; but at ATL there isn't a choice. The controller's demeanor was intimidating and unnecessary. I understand his arrival demand but with our current procedures we were doing the best we could.


Synopsis: A B737 crew on the ATL WARRR1 RNAV STAR were descending slower than expected due to weather which caused the TRACON Controller grief as it was conflicting with their outbound aircraft.