Small Transport
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor
Flight Crew Last 90 Days 100; Flight Crew Total 12500; Flight Crew Type 900
Situational Awareness; Confusion
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Clearance; Ground Incursion Runway
Air Traffic Control Issued Advisory / Alert; Flight Crew Became Reoriented
Environment - Non Weather Related; Human Factors; Airport
While departing SUA on an IFR flight plan; I was instructed to Runway 12. Taxiway A is roughly parallel to Runway 12; but has a slight 'bend' mid-span; as such; the taxiway sign attempts to reflect this bend with an angular depiction that doesn't directly mimic the actual taxiway layout. Further; the taxiway signage is set at an angle to the intersection of taxiways C & A; so that the layout depicted is further skewed to the actual layout of Taxiway A. This intersection is not indicated as a 'hotspot' on airport diagrams.During taxi; I was distracted by the momentary illumination of an annunciator light ('HYD'); while viewing this light; and while attempting to comply with the taxi instructions; I was confused by the taxiway signage and inadvertently crossed the hold short line for Runway 12. This was confirmed by radio communication from the Ground Controller; and I was instructed to taxi clear of the runway.Contributing to my confusion was my unfamiliarity with the airport (which I indicated to the Tower Controller upon arrival - I believe this was the same Controller who was acting as Ground Controller during my taxi outbound); and the layout of the aircraft's instrumentation following after-market modification (this was my third flight in this updated aircraft; and I had some difficulty in changing the scale of an airport taxi diagram depicted).
Small transport pilot reported a runway incursion due to a minor equipment problem creating a distraction; unfamiliar airport and confusing airport taxiway signage.