Date: 201306
Local time of day: 0601-1200
Location: HHR.Airport, CA
Flight conditions: IMC
Light: Daylight
Aircraft: Small Aircraft; Low Wing; 1 Eng; Retractable Gear
Operator: Personal
Operating under: Part 91
Flight plan: IFR
Mission: Personal
Flight phase: Initial Approach
Airspace: Class B LAX; Class D HHR
ATC / advisory: TRACON SCT
Aircraft component: GPS & Other Satellite Navigation
Component problem: Malfunctioning
Reporter organization: Personal
Reporter function: Pilot Flying; Single Pilot
Reporter qualification: Flight Crew Instrument; Flight Crew Private
Human factors: Workload; Training / Qualification; Human-Machine Interface; Communication Breakdown; Distraction
Anomaly: Aircraft Equipment Problem Critical; Conflict Airborne Conflict; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew; Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert; Flight Crew Returned To Clearance; Flight Crew Took Evasive Action
Contributing factors: Weather; ATC Equipment / Nav Facility / Buildings; Human Factors; Procedure
Primary problem: Ambiguous

Narrative: I filed IFR to HHR. Departure Tower handed me off to Approach. Approach gave me vectors for my climb to 5;000 MSL. Upon reaching altitude; Approach gave me direct an airway fix and handed me off to SCT Approach. I contacted SCT Approach after they acknowledged me; I then requested the GPS/WAAS approach for HHR. The Controller asked me to repeat the approach and then said OK. I made the same request with all subsequent controller handoffs. On contacting the last SCT Approach Controller prior to be handed off to Tower; he cleared me for the Localizer/GPS approach. I advised him I was direct WELLZ Intersection and had previously requested the GPS/WAAS approach and I was requesting the GPS/WAAS approach from him. While WELLZ is also on the localizer course; in GPS steering mode on autopilot; the GPS was warning of the upcoming steep turn ahead and was preparing for the turn. The vectors given by controllers for my course heading put me on a narrow downwind to the final approach course. The Controller stated that the approach was unable and to fly the Localizer/GPS approach. I had the localizer approach frequencies set up in my back up NAV 2. I use NAV 2 as a double check to NAV 1 which was in GPS steering mode coupled to the autopilot. I was in IMC at the time and did not want to argue with the Controller that the previous controllers had accepted my request for the GPS approach which is what my autopilot was flying. I began to transition from the GPS approach to the localizer approach. I had not briefed the localizer approach and was working to bring up the approach plate. The Controller called up and said I was 2 miles from HASHY and said to maintain 1;600 FT till established cleared for Localizer/GPS approach all while I was in IMC. I changed the autopilot from GPS steering mode to heading mode. I tuned in a left turn on the autopilot heading mode. The airplane autopilot turns at a standard rate turn. The Controller called and stated [that] I needed to make a much steeper turn to make the localizer. I disconnected the autopilot and I cranked the yoke over to the left and watched the localizer come in on NAV 2. Controller called in and stated he observed me established on the localizer. I didn't think I was established due to the extreme bank and I thought my momentum was going to take me past the localizer which is why I had not yet started my descent and I made no report of being established. I reached down to reset the GPS to HHR when I noticed the Multi Function Display which receives its information from the GPS screen was blank and the previous programmed procedure in the GPS flight plan was now gone. I tried to program the GPS for HHR and I got GPS integrity error. I had no way points; no airports; no intersections on my MFD; nor my electronic HSI moving map which are both driven by the GPS which had apparently had no signal. Further; the GPS is my DME and I had no reference to distance from airport or waypoints. I changed my EFIS from map mode to Localizer mode so I could have my full Localizer needle on the HSI in front of me over using the number two NAV needles. In this short period of time of resetting radios in IMC; and trying to figure out what happened to my GPS; MFD and EFIS along with the momentum of my tight turn caused me to drift 10% right. I got a call from the Controller warning me of the deviation in which case I turned 10% left as requested by the Controller. After the Controller saw my course correction; he asked me to contract Hawthorne Tower. After landing; I was instructed to call a number for which I was informed of a possible pilot deviation. As a result; I was informed that the Controller for LAX adjusted traffic for three arriving flights into LAX. When I heard this; I thought this was strange; since I had no traffic alerts displayed on my MFD from my Garmin Traffic Avoidance System; nor did I hear any audio alerts. It turns out based on a NOTAM that the DOD was conducting testing in the areawhich there was a low level chance it could create anomalies with flight deck systems and TCAS. I called the number on the NOTAM and spoke to a gentleman to report my loss of GPS Signal and my loss of targets on my Traffic Avoidance System. I asked if this would have been caused by their testing and he replied yes.In conclusion; I was mentally prepared for a GPS approach but given a different approach. The new approach required a steep turn to the localizer which created some drift. This was exacerbated when the avionics shut down which I rely upon for my situation awareness. In this short period of time of fixating on the avionics; I should have paid more attention to NAV 2 localizer and just fly the plane. I favor flying the WAAS/GPS approach; they are more accurate than the ILS. All the approaches I have flown in the last year have been GPS/WAAS approaches. My autopilot has GPS steering and it couples more accurately to the GPS approach then the localizer approach. Lessons learned; I do not routinely practice ILS approaches. I fly LPV approaches which look and feel the same as an ILS. As such; on approaches for a GPS approach; I need to not only tune in a back up approach; but I need to be prepared to fly the backup approach; including having the approach plate up and available. I need to add ILS/Localizer approaches into my practice currency. Most important of all; I should have considered going missed when my avionics went out and need to add that to my currency practice. Have my Ipad with backup GPS in case of panel GPS failure.




Synopsis: A pilot was prepared for the HHR Runway 25 GPS approach; but because of GPS signal disruption was cleared for the LOC then overshot final as he transitioned NAV equipment and mental mapping to the non precision approach.