Otto Instrument Service, began in business in 1946 in a 120 square foot leased office at Rubidoux Airport located in Riverside, California.  In September 1946, the Civil Aviation Agency (CAA) issued Otto Instrument Service Repair Station Certificate number 4005, which was changed to WE2R263L in 1990 when the Federal Aviation Administration (FAA) revised its Certificated Repair Station numbering system.  In may of 1978 Otto Instrument Service applied for and received a Limited Radio Rating, and in March of 1991 applied for and received a Limited Accessory Rating.  In February of 1993 Otto Instrument Service moved from its original facility to a new, larger, more modern facility, located in Ontario,CA Otto Instrument Service has been in continuous operation beginning in 1946 until the present. During this time Otto Instrument Service has maintained aircraft instruments for private aircraft, commercial aircraft, and the United StatesGovernment.