The F-110A was the USAF designation for what was to become the F-4C. On 18 September 1962, the USAF and US Navy aircraft designation systems were combined into a single scheme resulting in the F-1 to F-11. The USAF F-110A and US Navy F4H-1 became F-4C and F-4B respectively.
Operation High-speed, a fly-off competition between the USAF F-106A and the US Navy F4H-1 (F-4B) resulted in a convincing win for the F4H-1. The USAF was loaned two US Navy aircraft (BuNo 149405/406) for a 120-day extended evaluation on 24 January 1962. Twenty-seven more F-4Bs were eventually loaned to the USAF for service evaluation, most of which were returned to the US Navy after the F-4C entered production.
From Wikipedia: The F- series number sequence used in USAF was a continuance of the pre-USAF pursuit aircraft (P- series) numbering, stretching back as far as to the 1920s. The numbering would continue sequentially up to the F-111, and after this number the 1962 United States Tri-Service aircraft designation system restarted the numbering back from 1. Notably, the fighter-bomber briefly known as the F-110 Spectre was renamed F-4 Phantom II. The USAF continued the naming convention with the CONSTANT PEG program as an OPSEC measure. The last known aircraft with a "Century Series" designation is the F-117 Nighthawk stealth fighter.
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A copy of the Convair F-106A and F-106B Powerplant Technical Maintenance manual. (T.O.1F-106A-2-4) Dated 1 December 1962.
A copy of the T.O. 1F-106A-1CL-1 Flight Crew Checklist for the Convair F-106A/B aircraft, dated 1 February 1962.
A copy of the T.O. 1F-106A-3 Convair F-106A/B Structural Repairs Manual. Dated 16 August 1982.
A copy of the T.O. 1F-106A-1CL-1 Flight Crew Checklist for the Convair F-106A/B aircraft, dated 39 October 1978. 
A copy of the T.O. 1F-106A-2-1 for the Convair F-106A/B aircraft. Dated 15 November 1961. Credit: Anymouse Collection
A copy of the Convair F-106A/B Delta Dart Power Plant Technical Manual, T.O.1F-106A-2-4. Dated 1 December 1962.
A copy of the T.O. 1F-106A-1-1Flight Manual, for the Convair F-106A/B aircraft. Dated 1 December 1972. 
A copy of a later T.O. 1F-106A-1 Flight Manual for the Convair F-106A and B aircraft, dated 30 April 1985.
A copy of the Convair F-106A Illustrated Parts Breakdown Manual. Dated 1 January 1988. Credit: Anymouse Collection
A copy of the T.O. 1F-106A-2-2 TECHNICAL MANUAL 
A copy of the Convair F-106 AWCIS Condensed Maintenance Guide, T.O. 1F-106A-2-27-1. Credit: Anymouse collection
