Narrative:

It was the captain's leg. No other aircraft or crewmembers aside from the captain; myself (first officer); and the flight attendant were involved in the event. Runway xx (8;800 ft long) was in use and winds were nearly down the runway at around 15 KTS gusting to 25 KTS. The aircraft had already flown 2 legs that day. We began our takeoff and everything appeared normal on my (first officer's) side. I made the 80 KTS call and shortly after the captain received an indicated airspeed flag; which was then followed by an EFIS comparator monitor caution message. The captain immediately aborted the takeoff. We taxied off the runway; informed ATC and conferred with maintenance. They agreed with us that it was most likely a fluke or computer glitch because as quickly as it appeared the message went away and it was quite windy. We also spoke to the dispatcher and the dispatcher agreed that after letting the brakes cool it would be acceptable to attempt another takeoff. On the second takeoff attempt; the airspeeds were clearly not in agreement and the captain again received an indicated airspeed flag quickly followed by an EFIS comparator monitor caution; but by then the captain had already aborted the takeoff. We both decided something was definitely wrong and taxied back to the gate. The cause turned out to be water in the pitot static system. The event occurred because of a fault in the captain's pitot static system. Somehow water made its way into the system and caused faulty airspeed indications; detected by the aircraft and displayed as an indicated airspeed flag on the captain's side and an EFIS comparator monitor caution message.

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Original NASA ASRS Text

Title: A CRJ200 flight crew received an IAS flag and the caution message EFIS COMP MON. They decided to reject the takeoff; but after a second attempt with the same result; water was found in the pitot static system.

Narrative: It was the Captain's leg. No other aircraft or crewmembers aside from the Captain; myself (First Officer); and the Flight Attendant were involved in the event. Runway XX (8;800 FT long) was in use and winds were nearly down the runway at around 15 KTS gusting to 25 KTS. The aircraft had already flown 2 legs that day. We began our takeoff and everything appeared normal on my (First Officer's) side. I made the 80 KTS call and shortly after the Captain received an indicated airspeed flag; which was then followed by an EFIS comparator Monitor caution message. The Captain immediately aborted the takeoff. We taxied off the runway; informed ATC and conferred with maintenance. They agreed with us that it was most likely a fluke or computer glitch because as quickly as it appeared the message went away and it was quite windy. We also spoke to the Dispatcher and the Dispatcher agreed that after letting the brakes cool it would be acceptable to attempt another takeoff. On the second takeoff attempt; the airspeeds were clearly not in agreement and the Captain again received an indicated airspeed flag quickly followed by an EFIS Comparator Monitor caution; but by then the Captain had already aborted the takeoff. We both decided something was definitely wrong and taxied back to the gate. The cause turned out to be water in the pitot static system. The event occurred because of a fault in the Captain's pitot static system. Somehow water made its way into the system and caused faulty airspeed indications; detected by the aircraft and displayed as an indicated airspeed flag on the Captain's side and an EFIS Comparator Monitor caution message.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.