Date: 201306
Local time of day: 0601-1200
Location: TRK.Airport, CA
Flight conditions: VMC
Weather elements / visibility: 10
Aircraft: Skyhawk 172/Cutlass 172
Operator: Personal
Operating under: Part 91
Flight plan: VFR
Mission: Personal
Flight phase: Taxi
ATC / advisory: CTAF TRK
Aircraft component: Air/Ground Communication
Component problem: Improperly Operated
Reporter organization: Personal
Reporter function: Single Pilot
Reporter qualification: Flight Crew Commercial
Human factors: Situational Awareness
Anomaly: Aircraft Equipment Problem Less Severe; Conflict Ground Conflict; Less Severe; Ground Incursion Runway
Detector: Person Flight Crew
When detected: Taxi
Result: Flight Crew Became Reoriented
Contributing factors: Aircraft; Human Factors
Primary problem: Ambiguous

Narrative: I was taxiing in my 172 Skyhawk to the departure end of the active Runway 28 [at TRK]. There was clearly glider activity on the adjacent runway; as I had seen them taking off all morning and was paying attention to where they were headed. I was using an iPad with Foreflight as my primary navigation; supplemented with on-board GPS; and then chart pilotage. On taxi I noticed that my radio was very static-filled and scratchy. I was having a hard time hearing anything. My passenger noticed this as well; and asked me to turn down the radio (I declined). I thought that the problem with the radio was somebody else on the same frequency with a stuck mike or some other problem with the local CTAF frequency. I was in a hurry to takeoff; as the airport was already busy and I was concerned about density altitude; as it was forecast to be extremely hot. TRK is at about 6K MSL so it's high; and it was going to be hot. I was anxious and wanted to get out of there. I fueled up and taxied to the departure end of 28; and I crossed the intersecting runway where the gliders were operating without even stopping. I got a radio call from the tow plane on the runway as I crossed where he asked if I saw him. I responded with two clicks; as I was already past the center-line of Runway 1-19. The pilot of the glider made a radio call stating 'I think he has his radio turned down.' I responded with 'I hear you; but transmissions are barely audible and broken.'  I don't believe that the tow plane was moving yet; but they were about to begin takeoff roll. I realized what had happened at this point; and felt like this could have been a very close call. Nothing happened besides me scaring the glider and tow pilots; and then scaring myself; but there are a few factors here that contributed to this: 1.) I wasn't aware of the runway configurations; and I either ignored the signage or it wasn't very clear. I didn't know that I was crossing a runway (active or otherwise.) I was in a hurry; and stressed; but I still don't feel like the signage and markings were very clear. 2.) Using Foreflight on an iPad and a new Dual GPS unit; I had a new Scosche dual cigarette lighter charger that I purchased from [an aviation supply retail store] to power both the iPad and the GPS unit. I had used this on the way down with no issues. But; once airborne; I noticed that the radio noise was not going away. I began to be concerned that I was having dual radio failure; as this was happening on both of my radios. I was concerned about having total communication loss. I made a call to Tower and they read me loud and clear; but I was still having a very difficult time hearing anything. As I was troubleshooting this I unplugged the cigarette lighter charger. The noise ceased; and everything was OK. The charger was emitting frequencies that were reading my radio unlistenable. This was the number 1 problem in this entire situation; combined with poor situational awareness on my part; and being rushed. I was really surprised by this for two reasons: 1.) I had used this charger on the flight to TRK two days prior with no poor results. This was one of the reasons it took me a while to even test it. 2.) This charger was expensive and purchased because I thought it was shielded to prevent this kind of problem. I had heard of this problem happening with other cheap auto chargers; so I spent the 30 dollars on the better; aviation-specific charger. This was the closest call I have ever had. It was scary and stupid; and I accept responsibility for the close call. I learned something here. That said; something needs to be done to help insure that these kinds of chargers don't interfere with radios and other in-flight instruments. This could have been much worse. As the iPad and other electronics move into the cockpit we need to make sure that they help; and don't do harm. This is the future for sure (and I love Foreflight on the iPad; it's the best thing to happen in GA in a decadeor more) but let's make sure that we can make this move forward safely.




Synopsis: C172 pilot reported communication difficulty that led to a runway incursion that he later traced to interference from a power splitter.