Air Charter,
For the day I stood at Stansted with b***er all happening until late in the afternoon, out of the murk, appeared one of their Avro Super Traders which then performed a touch and go before landing and taxying on to one of the dispersal points. Only Tudor/Super Trader I ever saw flying. Also for their Super Freighters at Southend in the Fifties.
Channel Airways,
For their "Royal" Viking which took me to Ostend, Easter '63 for a football tournament and for their "Golden Viscount"s., one of which flew myself and Mrs S on honeymoon to Jersey.
Skyways,
For their beautiful pale blue Hermes and Yorks
Spantax,
For their DC-7C's which took me on my first international flight from Gatwick to Palma and return.
The list could be endless and, as mentioned in an earlier reply, includes most of the entries in Tony Merton Jones' magnificent epic "British Independent Airlines since 1946"
Cheers in nostalgia
Southender