Complex sentence: As part of the Australia-England air route there was a surface component from Galle to Karachi which added considerable time to the service this was later replaced by the Double Sunrise service, Karachi to England was flown by BOAC.
Split into simpler sentences: As part of the Australia-England air route there was a surface component from Galle to Karachi that added considerable time to the service. This was later replaced by the Double Sunrise service, with Karachi to England flown by BOAC.