EMB ERJ 170/175 ER/LR
Training / Qualification; Human-Machine Interface; Situational Awareness
Aircraft Equipment Problem Less Severe
Flight Crew Landed As Precaution; Flight Crew Diverted; General Declared Emergency; General Maintenance Action
Human Factors; Aircraft
While taking off; after pushing the thrust levers forward; we received an EICAS message that said the parking brake was set.  Realizing that it was impossible for it to be set; because we were accelerating rapidly; we continued the takeoff roll.  Once airborne the message cleared from the EICAS.  Approximately twenty minutes into the flight; the EICAS message reappeared.  We called Maintenance Control and they informed us that it was most likely an erroneous message.  Not feeling confident that the brake was not set we decided to divert to an airport that had longer and wider runways.  After discussing it with dispatch; we decided that KPIT was a good diversion airport.  We continued on to KPIT; declared an emergency with ATC; and landed uneventfully.  In the future I will call for a rejected takeoff.  This way we can better think about the situation and decide if we should continue or cancel the flight.
On takeoff and shortly after setting takeoff power; we got an EICAS message 'Emerg Parking Brake.'  I hesitated for a second in an attempt to mentally process this message.  We were approaching 80 kts at this time.  Since the aircraft was accelerating normally; I elected to continue the takeoff after deciding that this must be an issue with the aircraft's indicating system; and not with the parking brake itself.  On initial climbout; all messages on the EICAS cleared; and the flight proceeded as planned.  Fifteen to twenty minutes later; the EICAS message concerning the parking brake was presented; with the addition of the indication that the brake was applied.  We talked to maintenance concerning the issue.  The consensus from the maintenance department was that this was in fact an indication issue; and that the parking brake was really not applied.  I was uncomfortable not knowing for sure what the parking brake was actually doing at this point; so I elected to divert to an airport which had longer/wider runways.  As a precaution; we declared an emergency with ATC and had fire trucks standing by.  The landing was uneventful; and we taxied to the gate. Amazing how clear hindsight always is; as a simple rejected takeoff would have avoided the diversion.  In the future; instead of analyzing an EICAS message on the roll; rejecting the takeoff and problem-solving the issue clear of the runway may be the better choice.  My error was in trying to second-guess the aircraft's indicating system.
EMB170 Flight Crew experiences an EICAS message during takeoff indicating the parking brake is set; and continues the takeoff.  Once airborne the message clears on its own then reappears 20 minutes later.  After consultation with Maintenance the crew elects to divert to an airport with longer; wider runways.  The landing is uneventful.