Narrative:

My colleague & I were returning empty on an IFR flight plan part 91 from ZZZ. I was in the right seat acting as sic while my colleague was flying the aircraft from the left seat & acting as PIC. We switch roles in order to maintain our skills. The before landing checklist was performed after gear extension. This was done in a command / response manner. The landing was normal until the moment the nose tire contacted the runway. The airplane began veering hard to the right. My colleague was making every effort to return to the centerline of the runway but it was not bearing fruit. When we were about to exit the runway; I shouted 'steering!' at the same time; I checked to see whether the left rudder was pushed in. It was. We went traveling across a section of rocks. In doing so; we knocked over a taxiway sign & a light. The aircraft suffered FOD damage to both engines; wings & landing gear. There was also a fuel spill. I want to commend my colleague for regaining aircraft control the way he did. For a moment there; it was dicey when we were headed toward parked aircraft. Several possibilities come to mind: a centered tiller indication with a nose tire that was not actually centered. Confirmation bias with an uncentered tiller interpreted as a centered one. Something else.

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Original NASA ASRS Text

Title: HS-125 flight crew reported loss of directional control during landing resulting in a runway excursion.

Narrative: My colleague & I were returning empty on an IFR flight plan Part 91 from ZZZ. I was in the right seat acting as SIC while my colleague was flying the aircraft from the left seat & acting as PIC. We switch roles in order to maintain our skills. The before landing checklist was performed after gear extension. This was done in a command / response manner. The landing was normal until the moment the nose tire contacted the runway. The airplane began veering hard to the right. My colleague was making every effort to return to the centerline of the runway but it was not bearing fruit. When we were about to exit the runway; I shouted 'steering!' At the same time; I checked to see whether the left rudder was pushed in. It was. We went traveling across a section of rocks. In doing so; we knocked over a taxiway sign & a light. The aircraft suffered FOD damage to both engines; wings & landing gear. There was also a fuel spill. I want to commend my colleague for regaining aircraft control the way he did. For a moment there; it was dicey when we were headed toward parked aircraft. Several possibilities come to mind: A centered tiller indication with a nose tire that was not actually centered. Confirmation bias with an uncentered tiller interpreted as a centered one. Something else.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.