Small Aircraft; High Wing; 1 Eng; Fixed Gear
Flight Crew Instrument; Flight Crew Private
Flight Crew Last 90 Days 20; Flight Crew Total 2490; Flight Crew Type 100
Distraction; Situational Awareness
Aircraft Equipment Problem Less Severe; Airspace Violation All Types; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy
Aircraft Equipment Problem Dissipated; Flight Crew Overcame Equipment Problem
Aircraft; Human Factors; Procedure
I was flying VFR cross country to ZZZ from JZI flying direct with a planned northern deviation towards HYW to avoid MYR airspace. Altitude was 3;000 AGL due to moderate turbulence. As I was nearing MYR airspace the GPS encountered interference and the aircraft indicator on the moving map was blocked (later determined to be ADS-B shadow). When the GPS self corrected; I realized that I was near or touching the outer ring below the 4;000 upper limit and above the 1;200 lower limit. I immediately executed a 180 degree turn and then turned north and skirted the outside ring as planned. I did possibly touch the airspace but did so for only the minute it took to turn away. The certified GPS never gave the warning that it usually does when class airspace is entered; I had to range the GPS out near maximum to even see the touching of the outer ring; so I do not know what the ATC radar would have shown. I do not expect a re-occurrence as I better understand how the ADS-B shadow sometimes disguises the aircraft symbol. I have been flying nearly 40 years and have never had a violation or an airspace incursion.
Pilot reported GPS problems associated with ADS-B issues and a possible airspace violation.