Narrative:

While enroute with flight following; I turned on the auxiliary fuel pump. I switched tanks; and turned off what I thought was the fuel pump. I experienced a loss of power to the fuel gauges and made note of the time. I calculated that I had plenty of fuel and continued toward my destination. I assumed that the recent fuel tank repair was the cause of the current problem and checked the fuses; which were okay. At that time; I realized that I was without radios and activated my hand held radio. I contacted approach and told them that I was proceeding to haf. I requested that approach contact haf to facilitate visual confirmation of my gear being down. Approach informed me that due to the lack of tower at haf that sql would be able to confirm my gear down. I was aware that the master switch could be in the off position but I did not want to add to the already problematic situation by cycling it. I agreed with approach that proceeding to sql was appropriate and proceeded there. Approach tried to direct me to another frequency but I was unable to change the frequency and I requested to stay with them. They asked if I was using my PIC final authority for an emergency and I felt that they were requiring me to do so in order to continue helping me. So to fully cooperate I declared one. I then requested a change to pao for the landing due to my familiarity with its larger open spaces. I landed at pao and discovered that when I changed tanks I mistakenly turned off the master instead of the fuel pump. I have now practiced with the emergency backup radio and can change frequencies.

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Original NASA ASRS Text

Title: PA-28 pilot reported mistakenly turning off the Master Switch while selecting fuel tank.

Narrative: While enroute with flight following; I turned on the auxiliary fuel pump. I switched tanks; and turned off what I thought was the fuel pump. I experienced a loss of power to the fuel gauges and made note of the time. I calculated that I had plenty of fuel and continued toward my destination. I assumed that the recent fuel tank repair was the cause of the current problem and checked the fuses; which were okay. At that time; I realized that I was without radios and activated my hand held radio. I contacted approach and told them that I was proceeding to HAF. I requested that approach contact HAF to facilitate visual confirmation of my gear being down. Approach informed me that due to the lack of tower at HAF that SQL would be able to confirm my gear down. I was aware that the master switch could be in the off position but I did not want to add to the already problematic situation by cycling it. I agreed with Approach that proceeding to SQL was appropriate and proceeded there. Approach tried to direct me to another frequency but I was unable to change the frequency and I requested to stay with them. They asked if I was using my PIC final authority for an emergency and I felt that they were requiring me to do so in order to continue helping me. So to fully cooperate I declared one. I then requested a change to PAO for the landing due to my familiarity with its larger open spaces. I landed at PAO and discovered that when I changed tanks I mistakenly turned off the master instead of the fuel pump. I have now practiced with the emergency backup radio and can change frequencies.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.