Date: 201301
Local time of day: 0601-1200
Location: ZDV.ARTCC, CO
Flight conditions: VMC
Light: Daylight
Aircraft: EMB ERJ 145 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class A ZDV
ATC / advisory: Center ZDV
Aircraft component: Autoflight System
Component problem: Design
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Flying
Reporter qualification: Flight Crew Commercial
Human factors: Human-Machine Interface; Situational Awareness; Time Pressure; Workload; Distraction
Anomaly: ATC Issue All Types; Deviation - Altitude Crossing Restriction Not Met; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification
Contributing factors: Aircraft; Chart Or Publication; Human Factors; Procedure
Primary problem: Procedure

Narrative: Today; extremely high work loads on a complex RNAV STAR with strong tailwinds thrown into the mix led to an undesired aircraft state. We were too high and too fast. We were coming in on the TELLR RNAV STAR. We had a 60 or so knot tailwind. I was the pilot flying. I briefed the arrival ahead of time; but I did not brief the approach because I wasn't sure which runway we would get. However; I wanted to make sure I got a head start on the briefing because the work load is greatly increased on RNAV arrivals. We were already past our second fix on the arrival with an altitude restriction and a speed restriction--both of which were met with no consequence. Once the Captain obtained the ATIS and our gate I briefed the anticipated visual approach backed up by ILS to runway 16R. As soon as I finished briefing the approach; I went back to the arrival plate to check my next fix and crossing restriction. We were within a mile of the fix and the crossing restriction was at a 250KIAS speed and an altitude about a thousand feet lower than our current altitude. I asked the Captain to tell ATC that we were not going to make the speed restriction as we were already at 280KIAS over the fix. We still needed to continue descent as well. As with all of the RNAV arrivals; this one had to be constantly monitored because of multiple crossing restrictions and/or speed restrictions. There were several factors led to missing this restriction; but before I fault the Captain or myself I want to make my position very clear on these RNAV arrivals. These procedures are a HUGE safety risk for aircraft not equipped with autothrottles. Both pilots are preoccupied with breaking a restriction and a negative mark on their licenses because of the complexity level of these arrivals. As a result; during briefings it is typical for BOTH pilots to be reading their charts while at the same time backing each other up at these very high workload times. As a result; during the briefing; and often during the arrival; nobody is actually flying the airplane as both pilots are backing each other up on their charts. This is a result of too many to restrictions to remember without revisiting the charts throughout the arrival. For an airplane with autothrottles; these types of arrivals are an easy task. However; for an airplane that has to be manually managed to comply with altitudes and speed restrictions; it doesn't take too many outside factors for these arrivals to become a huge safety risk; i.e. icing conditions; strong tailwinds; runway change; call from flight attendant; etc. One other factor to consider is that once given a change of runway after established on one of these arrivals; there is no time to brief the new runway approach. This is because neither pilot can look away from their charts and/or the current state of the aircraft long enough to brief the new runway. The workload is too high. As a result; safety of flight is risked. One case in point: On several of these arrivals; the restricted waypoints are located very close together. From the first time I had to fly one of these arrivals into IAD and every time after; I have discussed with my captain--or thought to myself--that these arrivals are a huge safety risk to airplanes not equipped with the automation required to fly them as accurately as necessary while in congested airspace. It is well known that descent and landing are the flight crew's busiest phases of flight. Up until recently; the FAA has worked tirelessly on making the skies a safer place for all of us. I fear these RNAV arrivals are a step in the opposite direction. RNAV arrivals assigned to aircraft not properly equipped to fly them is a perfect place for human error to rear itself. We already know too well what the result of that ends up to be. It is my hope that the FAA will seriously consider this safety report along with others submitted since the widespread implementation of these RNAV arrivals; and consider restricting their usage to aircraft equipped with autothrottles only. Adding MORE of a workload during an already demanding phase of flight may save the FAA money in the way of ATC staffing and radio clutter; but my fear is that it will end in catastrophe. I will continue to voice my opinion with the hope that a change is made in favor of safety of flight over saving money. I'm not sure there is any way to better prepare for these types of arrivals because of the work loads and attention demanded. I believe these types of arrivals should be limited to aircraft with autothrottles. Human error is inevitable.




Synopsis: An EMB-145 First Officer made an articulate and pointed plea to limit ATC assignment of complex RNAV STARs (generically described as Optimized Descent Profiles; ODPs) to aircraft equipped with autothrottles. He states repeatedly that the flight crew workload associated with doing so on aircraft without such VNAV assistance is simply too high and constitutes a hazard to safe operations.