Date: 201907
Local time of day: 1801-2400
Location: SMO.Airport, CA
Flight conditions: Mixed
Light: Night
Aircraft: SR22
Operator: Personal
Operating under: Part 91
Flight plan: IFR
Flight phase: Final Approach
Airspace: Class E ZLA
ATC / advisory: TRACON SCT
Aircraft component: GPS & Other Satellite Navigation
Component problem: Malfunctioning
Reporter organization: Personal
Reporter function: Single Pilot; Pilot Flying
Reporter qualification: Flight Crew Private; Flight Crew Instrument
Human factors: Confusion
Anomaly: ATC Issue All Types; Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Executed Go Around / Missed Approach
Contributing factors: ATC Equipment / Nav Facility / Buildings; Procedure; Human Factors; Airspace Structure
Primary problem: ATC Equipment / Nav Facility / Buildings

Narrative: I filed IFR to land at SMO. The ATIS at SMO was reporting VFR conditions; but it was apparent as I was flying the 1st approach that this no longer reflected the prevailing conditions. As I was descending on the RNAV 21 for SMO; my GPS lost the signal somewhere after the FAF (Final Approach Fix). I went missed and informed the Tower. I came around for a 2nd approach; this time VOR-A. While being vectored to final for VOR-A; I interpreted an ATC instruction to turn left to a heading to intercept the final approach course. After starting the turn; ATC advised that the instruction was to turn right to that heading; and ATC advised that I was below the minimum vectoring altitude and needed to have a very tight turn. I advised that I had visual contact with the ground. I was VMC at this point; since the clouds were a marine layer closer to the coast. I intercepted the final approach course; and flew the VOR-A approach; but had to go missed again because I could not see the runway at the VOR minimums. I came around for a 3rd attempt flying the RNAV 21 GPS approach; but again the GPS signal went out at around the same point on final; so I went missed. I diverted to ZZZ.In terms of take-aways:(1) I would recommend checking whether other pilots have had GPS outages on that RNAV 21 approach into SMO. SMO Tower indicated that another pilot experienced the same; but it was unclear whether he was double-counting my experience. In my recollection; I have never experienced a GPS outage in my aircraft; and I noticed on the 3rd approach that both of my 430W units lost the signal; so I think it was something in the environment there.(2) Regarding the left vs right turn; I honestly don't know for sure what I was instructed to do or whether I read back left or right on the turn. I think that my mind registered 'left' because the final approach course was to my left; and intercepting it from my heading required less than a 180 degree turn whereas turning right involved more than a 180 degree turn. My personal take-away is to be more careful in the future about left vs right and double-confirm that I am implementing the correct instruction. I suppose ATC could emphasize the direction 'right' when that involves a turn of more than 180 degrees.




Synopsis: SR22 pilot reported experiencing GPS signal interruption on successive approaches to Santa Monica airport.