Flight Crew Commercial; Flight Crew Instrument
Flight Crew Last 90 Days 24; Flight Crew Total 2800; Flight Crew Type 1500
Confusion; Communication Breakdown; Situational Awareness
Deviation / Discrepancy - Procedural Clearance; Ground Event / Encounter Other / Unknown; Ground Excursion Taxiway; Ground Incursion Taxiway
Air Traffic Control Provided Assistance; Flight Crew Became Reoriented; Flight Crew Requested ATC Assistance / Clarification
Airport; Chart Or Publication; Human Factors; Environment - Non Weather Related
I was on the ramp at the FBO which is located at the end of the taxiway. I had received my IFR clearance for departure on Runway 7 on the clearance frequency. I then switched to the ground frequency and requested taxi clearance. (It was now well after sunset) I was told to taxi to Runway 7 via Foxtrot. I left the ramp and made an immediate left. Upon reaching Foxtrot 2; I realized that I wasn't actually on Taxiway Foxtrot; but was on a parallel road which was intended for vehicle traffic; not aircraft. I stopped at Foxtrot 2 and notified Ground control what had happened. I informed them that I could make a right onto Foxtrot 2 to get on the Foxtrot Taxiway. The controller notified me to hold my position and that he would send an Ops (Airport Operations) vehicle out. About 5 minutes later the Ops vehicle arrived behind me. The ground controller notified the Ops vehicle that I had stated that I could make the turn onto Foxtrot 2. The Ops vehicle approved that which I did and I made the right onto Foxtrot 2 and then left onto Taxiway Foxtrot and proceeded to the hold line for Runway 7 without further incident.After making the wrong turn on what I thought was Taxiway Foxtrot I did see a sign with an F on it with a black background on my right which is why I thought I was on Taxiway F. As I proceeded towards Runway 7. I commented to my passenger that there were several dips in the pavement which was unusual. As I approached F2; I saw a red sign past F2 indicating no entry. That's what was literally the red flag. Fortunately; I was in a high wing aircraft which cleared all lights and signs. This may not have been the case in a low wing aircraft. This second road was not shown on my airport taxi diagram which might have helped. I don't know if anyone else had ever made this same mistake; but I think better signage would have helped. Perhaps a sign coming out of the ramp on F1 indicating 2nd left to Foxtrot or a red no enter sign like the one at F2 might have might have also helped. I had not flown into this airport in over 15 years. I did not request progressive taxi instructions because the route appeared to be very simple. I will be more vigilant during night operations at unfamiliar airports.
GA pilot reported unknowingly taxiing on a vehicle roadway at ROC airport; thinking it was the taxiway.