Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Distraction; Fatigue; Situational Awareness
Ground Event / Encounter Other / Unknown
General None Reported / Taken
Airport; Human Factors
March AFB has unusual markings for Runway 12/30. We landed Runway 32 and taxied D; ramp; A then G to parking. On D; Runway 12 has a simple non-movement area stripe on Taxiway D and a red runway sign; but no wig-wag lights; and you do not physically cross the runway. The runway overrun abuts the taxiway. What's really bizarre is Runway 30 on Taxiway A. According to the Jepp chart; Runway 30 and its overrun impact Taxiway C and don't come anywhere near Taxiway A; and yet Ground Control issues a clearance to cross as if it did. Again; minimal signage/markings for a runway that doesn't exist at Taxiway A. This was after a 5.5 hour red eye from ZZZ. I should've been more alert on Taxiway D but Runway 12 never even occurred to me as a threat; mainly because of no wig-wags. Luckily; Ground cleared me across before it was a factor. Much more puzzling is Runway 30 on A. I just don't get it; that runway has no impact on A except maybe the threat of our tail height to a small civilian aircraft. Even after being alerted to the threat on D; I was shocked to see another runway sign on A. Had Ground not been pre-emptive with crossing clearances; there was a great chance we would've taxied blissfully across both 'runways' without hesitation. Fatigue was absolutely a factor in this case but even on a normal day; the poor signage and lack of similarity to every other runway crossing we encounter could have led to an unauthorized crossing.
Air carrier Captain reported non-movement areas at both ends of Runway 12/30 are confusing and stated signage is poor in that area.