Date: 201603
Local time of day: 0601-1200
Location: CLT.Airport, NC
Flight conditions: VMC
Light: Daylight
Aircraft: Regional Jet 900 (CRJ900)
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Descent
Airspace: Class B CLT
ATC / advisory: TRACON CLT
Aircraft component: FMS/FMC
Component problem: Design
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Human factors: Situational Awareness; Confusion
Second reporter function: First Officer; Pilot Not Flying
Anomaly: Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Became Reoriented; Flight Crew Overcame Equipment Problem
Contributing factors: Aircraft; Human Factors
Primary problem: Ambiguous

Narrative: While descending via the PARQR ONE RNAV ARRIVAL we had a course deviation at BOATN fix. The aircraft was cleared to descend via the PARQR ONE landing south. VNAV was engaged and the aircraft was descending on both vertical and lateral profile. As part of the FMS logic; an approach must be selected in order to populate the appropriate fixes for the transition. Since we were assigned landing south we inputted the ILS 18R at CLT; which in my experience is the runway assigned for landing south from that direction better than 90 percent of the time. As we approached BOATN; ATC informed us to expect runway 18C. The First Officer (FO) selected the ILS 18C in the FMS; and after confirming his selection I instructed him to execute the programming. Immediately; the FMS showed a discontinuity and the auto pilot reverted to FMS/Pitch mode. This occurred a matter of seconds before BOATN. I recognized the issue right away; however because of the discontinuity the autopilot failed to initiate its turn to CAMPR. I immediately selected heading mode and VS mode on the autopilot; and steered to aircraft left towards CAMPR. However because of reaction time the aircraft overshot the turn. ATC queried moments later as to the overshoot; and we informed them of our on going turn to CAMPR. Speed and altitude restrictions were met. Several seconds later we were assigned a heading and altitude. The flight continued uneventfully. After landing; we were told by ramp that CLT ATC wanted us to give them a call. I contacted ATC after parking and explained the above time line to them. They informed me that no loss of separation had occurred; but with this being a new arrival; wanted to have a discussion about the probable cause. After discussing with other [Company] pilots; I was informed that the 900 FMS will create a discontinuity when a new runway is programmed in on arrivals with programmable transitions. If this is true; I was; and I believe my FO was; unaware of this pitfall. I have never observed this phenomena before in any aircraft we operate. If this is a known issue; and I'm not saying it is; I would fault a lack of information dissemination and training as a contributing factor. Regardless; the proximity to the fix when the discontinuity occurred made an overshoot improbable to avoid. For my part; I believe in the future I will have to insist on viewing the LEGS page of the FMS before executing an approach selection.


Second narrative: I have not known this to happen before but I will definitely be verifying on the legs page all fixes next time we have to change approaches in VNAV on an arrival. I believe it is a major glitch in the system since the fixes still display on the MFD. Hopefully this will let both [Company] and Bombardier know of the anomaly.


Synopsis: A CRJ-900 flight crew reported difficulty programming the FMS following a late runway change during arrival to CLT airport.