Date: 201905
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Aircraft: Q400
Operator: Air Carrier
Operating under: Part 121
Mission: Passenger
Flight phase: Landing
ATC / advisory: Ramp ZZZ
Aircraft component: Antiskid System
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Second reporter function: Pilot Flying; First Officer
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor; Ground Event / Encounter Other / Unknown
Detector: Person Passenger; Person Flight Crew; Person Flight Attendant
When detected: Taxi
Result: Flight Crew Requested ATC Assistance / Clarification; General Maintenance Action
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: Immediately after a normal landing; we got a single chime master caution for inboard anti-skid. A rollout procedure without any braking was executed. Some subtle vibrations were experienced immediately after touchdown. While taxiing to the gate; Flight Attendant B called and reported a passenger on the right side of the aircraft observed smoke coming from the right brake assembly. That was followed by a second call from the Flight Attendant shortly thereafter reporting that there was fire observed from the same brake. At that time; we were very nearly parking at the gate and the Ramp Marshaler signaled we stop and then gave the signal for fire. We stopped and set the parking brake and asked Ground Control for the fire trucks as we had reports of fire from the right brake.First Officer suggested we start the APU and shut down the engines. Did normal shutdown as fire trucks arrived. First Officer and I decided keeping the folks onboard was safest course of action at that point. We did experience difficulty establishing communication with fire battalion commander to get a situation report. He reported 400 degrees; smoke; and an active hydraulic leak at the brakes. At that point; we noticed we had zero parking brake pressure so First Officer requested ramp chock the wheels. Once evaluated and deemed safe for deplaning by Maintenance personnel; a normal deplaning was made from our current position approximately 100 feet short of normal parking spot. During the debrief with the flight attendants; it became very clear that we came close to passengers electing to emergency evacuating themselves. I had made one P/A previously that fire crews had the situation under control and we were waiting for an aircraft mechanic to evaluate the condition of the aircraft but I was unaware that the situation was escalating. My plan was to have Ramp tug us to the parking spot just 100 feet more so we could deplane the pax in a normal fashion. I made a P/A to this effect and Flight Attendant B called and relayed that a passenger with maintenance background advised against towing the aircraft as he had observed the right main tire wobbling significantly. We relayed this to operations and made a plan with them to deplane from our current location. I called flight attendants to share plan. They asked me to make a P/A. I did stating main cabin door only when opened by Ramp personnel who coordinated a normal deplaning from our present location.It can be difficult to get enough information to fully understand what is going on. The flight attendants did a very good job keeping the passengers in their seats and keeping the isle clear of personal belongings. We were fortunate in many ways; first that the #3 main tire did not separate from the axle; we were able to stop the aircraft with brakes; that the Fire Department responded quickly; and that we ended up close to the gate.


Second narrative: During what I considered a smooth Q400 landing; we experienced an 'inbd antiskid' caution light on roll out. We got off the runway; ran the appropriate checklist and continued towards the gate as everything seemed normal except for the caution. As we turned onto [the taxiway]; Flight Attendant B called and said passengers on the number 2 side of the aircraft near the landing gear saw smoke and fire coming from the right main landing gear. We stopped short of the gate and accomplished the relevant parts of the 'engine shutdown/fire on ground' checklist and immediately called for ARFF. The trucks showed up within two minutes and by the time they arrived the fire had extinguished but smoke was still present as hydraulic fluid was actively dripping onto the hot wheel assembly. The Fire Commander stated that his indications showed the brakes being at 400 degrees. During the entire landing and roll out stage; no braking was applied as the headwind and performance didn't require it. On taxi in; braking was minimal. It was relayed to us from Flight Attendant B that the inboard wheel on the right main landing gear was wobbling. With the hot brakes; leaking hydraulic fluid; and unstable gear; we made the determination to not move the aircraft and to deplane the passengers where we were parked (about 100 feet short of the stop bar). We coordinated with Ops to position ramp personnel every 20 feet to help guide the passengers safely into the terminal. There were no injuries to passengers or crew and I feel that the situation was handled calmly [and] professionally. ARFF arrived quickly and were a great help. We could have made more PA's even though we ourselves didn't have many answers. A reassuring voice would have been nice for the passengers. Cause seems to have been a failed bearing on the inboard wheel of the right main landing gear assembly.


Synopsis: Q400 flight crew reported being advised by a Flight Attendant that they had a smoking brake after they landed with an anti-skid warning message.