Helicopter
Flight Crew Rotorcraft; Flight Crew Commercial; Flight Crew Instrument
Flight Crew Last 90 Days 48; Flight Crew Total 2100; Flight Crew Type 400
Confusion; Distraction; Situational Awareness
Airspace Violation All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR
Human Factors; Airspace Structure; Chart Or Publication
While performing power line inspections and survey work in the Norfolk International airport area; I inadvertently and unknowingly penetrated the Class D airspace for Norfolk NS Chambers NGU approximately 4 miles to the southwest of the airfield. As shown on the VFR sectional chart the altitude of 400 ft AGL being used to survey the power lines placed the aircraft well under the 1200 ft to 4000 ft altitude of the Class C airspace of Norfolk International outer shelf. Since none of our inspections required entry into the surface to 4000 ft airspace around Norfolk International or the 2000 ft to 4000 ft inner shelf I did not contact Norfolk. I was squawking 1200 VFR on the transponder and proceeded to inspect the power lines and structures in the area. Upon completion of the survey work of these lines that terminated immediately by the water's edge I turned NW toward Class D airspace. I contacted ATC before entry into and remained in contact with each ATC controller respectively while performing the aerial survey flight.Upon returning to our point of departure that afternoon I was informed that that one of the power lines went into a Class D surface to 2000 ft controlled by NGU. I reviewed the VFR sectional again and saw as before the magenta lines defining the Class C airspace for Norfolk Int. but no blue dotted or dashed lines that are the initial indication of Class D airspace. I looked at the VFR sectional closer and saw NGU Tower frequency and the ceiling elevation but still no airspace defining blue dashes or dots. I then magnified the VFR sectional on my Foreflight application to a level that is unrealistic for flight purposes and there hidden within the shading of the magenta Class C inner shelf I saw the blue dotted lines. These dots which are virtually invisible and hidden constitute a flight hazard and risk to many pilots who are flying VFR and may be unfamiliar with this particular oddity. This particular airspace needs to be amended to indicate the presence of the Class D airspace in a clearly out lined definition of blue dots that are a VFR pilot's first and most immediate indication of its proximity. This definition needs to be independent of the Norfolk Int. magenta Class C so as to be EASILY identifiable. If I had not been denied the blue dot/dash line indication I would have properly contacted the appropriate controlling agency for the airspace for permission to enter and work inside their airspace. It is upsetting to have the airspace classification and limit boundaries that is so easily utilized by pilots to be needlessly hidden from view.
Helicopter pilot reported violating Class D airspace while conducting aerial survey and  inspection work.