Regional Jet 200 ER/LR (CRJ200)
Flight Crew Air Transport Pilot (ATP)
Confusion; Distraction; Situational Awareness; Time Pressure; Training / Qualification; Workload
Deviation - Speed All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Human Factors; Procedure; Company Policy; Aircraft
During the LTOWN RNAV STAR into Memphis we missed the 210 KTS speed at DASAC.I had reviewed the company memos and the OPS bulletin and even talked to the Chief Pilot the day I started this trip because of that memo. We briefed this arrival and actually discussed the arrival most of the flight. We were so concerned about doing it correctly and not missing altitude restrictions that we missed this speed. I have not done this arrival into MEM before so lack of experience was also a factor. I believe that these types of arrivals are better suited to aircraft that are more appropriately equipped with LNAV/VNAV/auto throttles etc. It is my opinion that the distraction that this labor intensive type of arrival; being done for the first time or very infrequently; not to mention if there had been bad weather in the area; is somewhat unsafe. I think that all the misconceptions and confusion that made the issuance of another memo demonstrates that this is a problem.
We were approaching MEM on LTOWN Arrival. I was pilot flying and Captain was pilot monitoring. We talked about the STAR extensively as we had apprehensions about compliance with both the STAR and what we understood to be SOP. I had flown the LTOWN and several other STARS into MEM in recent months and felt fairly familiar. The Captain had not flown more than a few and was not feeling comfortable. We discussed the various ways I had observed other Captains fly the STARs in order to be assured of compliance with crossing restrictions as well as what we understood to be company guidance for the procedure (following the 'snowflake' and disregarding the green VNAV information; etc.). We did not hear any traffic in front of us on the arrival; and it appeared we were the only aircraft on the STAR at the time. We loaded the arrival with the 'landing north' transition and the approach in the FMS and verified the restrictions. Briefed the STAR and the approach and how we planned to fly it. When cleared to 'descend via' we set 3;000 FT in the altitude alerter to match the hard altitude restriction at DINKE Intersection and followed the 'snowflake' for vertical guidance. This required a fair amount of manipulation of the vertical speed; but we were able to follow fairly accurately. This procedure BARELY met the crossing restrictions at LTOWN (between 10;000 FT and 16;000 FT - we crossed the fix right at 16;000 FT) and then required a considerable level off before reaching DASAC. We slowed to 250 KTS at DAPLE as specified; but while considering when/how to continue descent and meet the restrictions; we did not slow to 210 by DASAC as specified. As there did not seem to be any other traffic; ATC may not have noticed our speed; and they did not ever call it out to us. As we were about to turn base for 36R; we realized we had not made the speed reduction. It did not affect our approach or landing in any way. These arrivals are creating a lot of uncertainty and anxiety for CRJ crews. They are unnecessarily complicated / ambiguous and create far too many opportunities for violations. Company guidance; as we understand it; is directing us away from the 'safe' way to fly them ('dive and drive' to each fix - very unwieldy and inefficient; but better assurance of compliance).
A CRJ-200 flight crew addressed their reservations about the suitability of their aircraft's autoflight systems to comply with the constraints of the LTOWN RNAV STAR (an Optimized Descent Profile) into MEM without excessive monitoring and intervention by the flight crew.