Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Confusion; Distraction; Situational Awareness; Troubleshooting
Aircraft Equipment Problem Critical
Flight Crew Rejected Takeoff; Flight Crew Returned To Gate; General Flight Cancelled / Delayed; General Maintenance Action
Aircraft
We were operating from ZZZ to ZZZ1. I was the pilot flying and the FO (First Officer) was pilot monitoring. We were performing a normal takeoff when shortly after the 'thrust set' callout; we noticed that our two primary airspeed indicators came alive at different stages. My airspeed indicator came alive at around 35 KIAS while the FO's airspeed indicator at around 65 KIAS. The two primary airspeed indicators then maintained about a 20 KIAS difference between each other.Moments thereafter we also received an 'SPS ADVANCED' EICAS caution message along with yellow IAS [mismatch] on the PFDs (Primary Flight Display). We safely performed a rejected takeoff below 80 KIAS as per AOM; notified ATC; notified the Flight Attendant (FA) and passengers; and monitored our brake temperatures. We safely vacated the runway and notified Company. After discussions with Company; we determined that the issue would require that we return to the gate. So we coordinated with Company and Operations and safely taxied back to the gate. Incidentally; we already had mechanics on board our airplane. So after returning to the gate I wrote up the aircraft and the mechanics immediately began to troubleshoot the problem. A few hours later; Maintenance signed off the issue after determining that they had resolved the problem. We subsequently contacted Dispatch; received an amended release; and taxied back to the runway for our second takeoff attempt. Unfortunately; we then had to perform a rejected takeoff below 80 KIAS yet again due to similar circumstances regarding our varied airspeed indicator values and 'SPS ADVANCED' EICAS message. We also received a transient red EICAS message; but it disappeared before we were able to read the message. We again safely performed a rejected takeoff below 80 KIAS as per AOM; notified ATC; notified the Flight Attendant and passengers; and monitored our brake temperatures. We safely vacated the runway and notified Company. We also coordinated with Company and Operations and safely taxied back to the gate for the second and final time. The flight was subsequently cancelled and the crew and myself felt it was safest that we not continue flying that day due to the stressful nature of having performed two back-to-back rejected takeoffs in one day.I suggest we incorporate an 'airspeed alive' callout so that we can catch divergent airspeed indicator values sooner rather than later. In this case; we quickly caught the erroneous airspeed indications early enough to initiate the abort at low speed; below 80 KIAS.This event also made me realize how short the amount of time is between the moment the airspeed indicators come 'alive' to when we approach 80 KIAS. This doesn't leave a lot of time to catch potential air data computer issues before entering into the high speed phase of the takeoff roll. This requires a very quick and accurate scan of the all three airspeed indicators in order to identify a problem and perform a rejected takeoff below 80 KIAS; i.e.; in the low speed takeoff phase.
Report narrative contained no additional information.
EMB145 Captain reported rejecting the takeoff roll twice due to unreliable airspeed indicators.