Gulfstream V / G500 / G550
Flight Crew Air Transport Pilot (ATP)
Troubleshooting; Situational Awareness
Aircraft Equipment Problem Less Severe; Ground Event / Encounter FOD
Aircraft Aircraft Damaged; General Maintenance Action
Environment - Non Weather Related
During post flight and re-fueling at ZZZ crew noticed a gash in the aircraft skin just forward of the single point refueling door.  Gash was about 16 inches long and ½ inch wide and was symmetrical and squared at each end. The gash was directly in line and aft of the right nose gear.  It appears that FOD was flipped up by the nose wheel on takeoff or landing leading to damage.  However; no unusual noises or vibrations were noted by crew but takeoff and landings are noisy events.  Preflight inspection was performed by Pilot in Command (PIC) with no damage noted.  Both pilots performed pilot's walk around with no damage noted. Both pilots have a habit of either opening and inspecting fuel door or physically touching the door to ensure it is securely closed.  It would be virtually impossible to physically touch the refueling door and not notice the gash.
Upon post-flight inspection in ZZZ; an indentation/gash of approximately one inch wide and 16 inches long was discovered on the underside of the aircraft. The cut did not appear to puncture deep enough to impact the pressure vessel. The length of the cut was in-line with the aircraft and appears to be in a prime location for an object (FOD) to have been kicked up by the nose-wheel on takeoff or landing. An independent walk around was performed by each crew member on the ground prior to flight; per SOPs. Due to the location of the strike near the single point re-fuel point; we are both certain the damage was not there prior to taxi-out. Upon discovery; a sweep of the runway in ZZZ was requested and no obvious object for the damage was found.
Upon post flight inspection a gash was noticed on the underside of the aircraft near the single point refueling station. The reporter attributed the damage to FOD encountered during the takeoff or landing phase.