Human-Machine Interface; Confusion; Communication Breakdown; Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Other / Unknown
Aircraft Equipment Problem Dissipated
Aircraft; Airport
Departing Runway 9 at MMH; with a very light passenger load; we performed a static thrust takeoff; thrust levers were set to T/O prior to brake release. At approximately 60-70 KTS we hit a bump in the runway and received a 'GLD [Ground Lift Dumpers] UNSAFE' caution message. The Captain started to retard the thrust levers at which point the message disappeared and the Captain advanced the thrust levers back into the T/O position citing a concern about the stopping ability of the aircraft. We continued the takeoff uneventfully and continued the flight to our destination with no further issues. We did not receive the 'GLD UNSAFE' on landing.The bump in the runway may have caused a fluctuation in the radar altimeter causing the message to be displayed. Since there was a concern that the aircraft's stopping ability may have been affected continuing the takeoff was a prudent decision; however after the initial reaction of bringing the thrust levers out of the T/O detent an abort would have also been warranted. There was very little time for me to react or speak up but I also should have been more assertive in stopping the aircraft after the thrust levers were retarded.Best way to avoid the situation would be by making a plan of action and adhering to it. If there may be messages that we are to disregard then they should be briefed ahead of time. However; once any action to abort the takeoff is made it should be carried out.
A Medium Transport flight crew departing MMH got a momentary GLD UNSAFE warning as they approached 80 KTS. The Captain initially began to reduce thrust to reject the takeoff; but reconsidered; re-established takeoff thrust and continued the takeoff successfully.