Date: 201206
Local time of day: 1801-2400
Location: ZZZZ.Airport, FO
Aircraft: B767-300 and 300 ER
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Flight phase: Takeoff / Launch
ATC / advisory: Tower ZZZZ
Aircraft component: Generator Drive
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Confusion; Communication Breakdown; Human-Machine Interface
Second reporter function: Relief Pilot; Pilot Flying
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Automation Aircraft Other Automation; Person Flight Crew
When detected: In-flight
Result: Flight Crew Rejected Takeoff; Flight Crew Returned To Gate; General Flight Cancelled / Delayed
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: During First Officer's takeoff he noticed the right engine generator DRIVE light had illuminated just prior to 80 KTS. He announced the problem and then began to reduce the throttles by a knob width. I decided to continue take-off and re-advanced throttles when the First Officer said something like; 'We're below 80 KTS; I think we should abort.' I then assumed control of the aircraft; moved the throttles to reverse; observed the Speed Brake Handle deploy and felt the Auto Brakes engage the RTO mode. Since we had adequate runway ahead of us; I moved the Speed Brake handle forward to disengage the RTO system and then redeployed them allowing the aircraft to decelerate with reverse thrust on both engines and gentle manual braking to the end of the runway. I directed the First Officer to notify tower of our situation and asked the Relief Pilot to reference the QRH Aborted Take-off data for our gross weight and 80 KTS or less info. After turning the aircraft around; I asked the First Officer to back-taxi down the runway while I informed our passengers of our need to return to the gate and to follow the Flight Attendants' instructions. I re-assumed control taxiing and had the First Officer request ARFF to inspect our brakes. The Relief Pilot confirmed no Brake Cooling Issues at 80 KIAS. Since we weren't sure if our speed had reached 90 KTS (since RTO triggers at 85 KTS or greater); I asked the Relief Pilot to recalculate for 90 KTS which required 19 minutes cooling time. ARFF confirmed our brakes were neither hot nor smoking so we taxied back to the gate.


Second narrative: It was at night and the weather was CAVOK. We were cleared for takeoff on Runway 17R; braking action good; dry runway; wind 300/6; and temperature 12C. As the First Officer was pushing up the power he called out a Right Gen Drive failure EICAS message; recommended an abort to the Captain and started to bring back the throttles. The Captain called for transfer of control; evaluated the situation and elected to abort. The abort was initiated below 80 KTS and the maximum speed I noted was approximately 80 KTS.


Synopsis: Some confusion reigned aboard a B767-300ER when the First Officer as pilot flying noted an EICAS GEN DRIVE FAIL message as they approached 80 KIAS and called out the light while beginning to pull back the thrust levers to reject the takeoff. The Captain assumed control and opted to continue the takeoff; pushing the throttles forward again until feeling RTO braking engage at which time the takeoff was rejected.