Date: 201810
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: 5
Light: Night
Aircraft: B767-300 and 300 ER
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Cargo / Freight / Delivery
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Situational Awareness
Anomaly: Ground Event / Encounter Ground Strike - Aircraft
Detector: Person Flight Crew
When detected: Routine Inspection
Result: General Maintenance Action
Contributing factors: Procedure; Human Factors; Weather
Primary problem: Ambiguous

Narrative: Upon arrival; evidence of tail strike (minor scrape on tail skid) was evident on the aircraft postflight inspection.[Before departing]; we had discussed that due to the heavy weight airplane (399K) and the gusty winds that we should perform a max thrust takeoff. The load specialist brought the load plan and explained that cans had to remove and repositioned due to a weighing error. We also received an [amendment] from our Dispatcher due to an increase in payload informing us of our required taxi burn to be under our max takeoff weight. We pushed and had about a 44 minute taxi due to traffic congestion so the fuel burn and takeoff weight was subsequently not an issue. As we approached the end of the runway there were multiple reports of windshear (+/-10 knots gain/loss on final and on departure). We considered re-running the takeoff data to account for gusting winds but decided that selection of a maximum power takeoff would be sufficient.The takeoff was normal with the exception of continuous gains and losses of 10-15 knots on takeoff roll; rotation and climbout. Nothing unusual regarding aircraft attitude or excessive rotation on departure was noted. On arrival; the Captain planned and briefed the ILS approach. The weather was clear and the winds were light. On descent the Captain discussed the need to be below 23.5 on the fuel in order to not exceed max structural landing weight of 326. We reached that level on the descent; so landing weight was not an issue. Our Vref was 147 giving us an approach speed of 152. We were asked to maintain 165 knots to a 4 mile final; which we complied with; and slowed to approach speed by approximately 1;500 feet AGL.The aircraft was stable at the 1;000 foot call. The approach continued to be stable; with the exception of a slightly higher sink rate at approximately 30 feet AGL. The Captain appeared to check the descent rate slightly using back elevator pressure. On touchdown the nose rose slightly; almost imperceptibly; and the Captain quickly corrected the attitude and lowered the nose to the runway. Neither the IRO nor myself thought the sink rate; flare or slight nose rise were excessive. After approximately 30 minutes the IRO went to preflight the exterior of the aircraft. When he returned he stated that the tail had been scraped slightly. We informed the mechanic and because he had possession of the logbook he entered the irregularity at that time. The mechanic returned after about 30 minutes and performed the deferral procedure and the aircraft was cleared. The Captain contacted our Dispatcher in the interim to request that the cans be weighed; remembering the irregularities that had occurred with loading. Additionally; no EICAS messages or unusual conditions were noted on takeoff or after landing.




Synopsis: B767-300 First Officer reported finding evidence of a tail strike after landing; although no one was aware of when it might have happened.