Date: 202102
Local time of day: 1201-1800
Location: BTR.Airport, LA
Light: Daylight
Aircraft: Commercial Fixed Wing
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Tower BTR
Aircraft component: Main Gear
Component problem: Improperly Operated
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Not Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Human factors: Communication Breakdown; Situational Awareness
Second reporter function: Pilot Flying; Captain
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Excursion Taxiway; No Specific Anomaly Occurred Unwanted Situation
Detector: Person Maintenance; Person Flight Crew
Result: General None Reported / Taken
Contributing factors: Environment - Non Weather Related; Chart Or Publication; Airport
Primary problem: Chart Or Publication

Narrative: We landed in BTR. We were instructed to roll out to the end of the runway and exit left onto Taxiway Foxtrot. I remember seeing a NOTAM that B between Alpha and 4R was closed. Foxtrot was on the opposite side so we confirmed that Tower wanted us to exit left onto Foxtrot. They said affirmative left on Foxtrot and we complied. The CA (Captain) slowly steered us off Runway 13 and onto Taxiway Foxtrot. He was on centerline the entire time. At this point; I was getting the flaps up; clock started; APU started; and the rest of the after landing flow. Immediately after this; I called up ground for further taxi instructions. I felt a slight dip in the left side and we were unsure of the cause. The Captain said he added some power and the airplane continued to roll forward taxiing. I was focused on getting some complex taxi instructions from ground that were abnormal and a bit confusing. It took several calls for me to clarify the taxi instructions. When we parked at the gate; I went out to do my post flight walk around. The ground crew was already taking pictures and I could see dirt on the left side wheels. That's when it clicked that the left wheel had gone into the grass. I informed the Captain of the left wheel; and he called maintenance as well as informed Dispatch.Tower advised us to 'exit left at the end on taxiway Foxtrot' and to contact ground when off. We complied with their instructions. There is no mention of wingspan restrictions or weight limits for Taxiway Foxtrot. The company documentation does not make mention of any restrictions to Taxiway Foxtrot either. While the CA was on centerline; oversteering is needed for this taxiway - there is no mention of this on the 10-09.A note should be added prohibiting air carriers on Taxiway Foxtrot. At the very least; there should be wingspan restriction or weight restrictions. Additionally; tower should have instructed us to back taxi on the runway rather than tell us to exit on Taxiway Foxtrot.A note should be added prohibiting air carriers on Taxiway Foxtrot. At the very least; there should be wingspan restriction or weight restrictions. Additionally; tower should have instructed us to back taxi on the runway rather than tell us to exit on Taxiway Foxtrot.


Second narrative: Landed on Runway 13; rolled to the end; Tower gave instructions to turn left onto Taxiway F; I stopped the aircraft before turning asked the FO (First Officer) to query Tower if that was correct because I originally briefed that we would exit right and taxi towards the terminal located on the West side of the airport; the Tower Controller replied; yes; turn left and contact Ground Control for further taxi instructions. With my nose wheel on the centerline; I slowly and cautiously rounded the bend on Taxiway F; felt the left side of the airplane sink a little; maybe 3-4 inches; and added a little more thrust; 3/4 to a full knob of the left engine to keep rolling; after a few feet we were back on the asphalt. Once at the gate; I inspected the left gear and found dirt on the wheels; I then called Maintenance Control; filled out the LOG and contacted Dispatch.BTR ATC gave us the taxi instructions that caused this.Should have been allowed to exit right; then taxi via B; turn right on either Taxiway E or Runway 4R and then left on Runway 13/31; then left on Taxiway A into the terminal ramp.


Synopsis: Air Carrier flight crew reported the aircraft left main landing gear left the taxiway while the aircraft was on the taxiway center line at BTR airport.