Part 1, options for the initial acquisition of the capability
1. Jellicoe recommended the Australia procure a number of carriers to support the two proposed Fleet units
2. Australia builds a small carrier instead of the Seaplane Carrier HMAS Albatross
3. Australia obtains or orders a carrier as part of a pre-war rearmament program
4. The UK loans or transfers one or more carriers to the RAN during the war
5. The RAN provides the personnel to crew one or more UK carriers during the war
6. The UK transfers a surplus carrier or two to the RAN post war
7. Australia buys a still in build carrier or two from the UK post war (as actually happened)
Part 2, options for the retention of the capability through the Cold War
1. Modernise existing carrier(s) to operate modern aircraft (planned, did not happen)
2. Modify carrier(s) still in build (as actually happened)
3. Order new build carrier(s) incorporating improvements (proposed)
4. Purchase already modernised / modified carrier(s) (proposed and preferred option)
Part 3, retention of or replacement of the capability late / post Cold War to present day
1. Decide CTOL or STO/VL
2. Modify existing carrier(s)
3. Purchase existing suitable / modernised ship
4. Build suitable design
Over arching requirement is for Australia to develop a grand strategy and stick to it. Assume carriers are determined as required to fore fill the objectives of the strategy.
Bits and pieces I have picked up over the years (some read some heard and unconfirmed)
1. UK intended to transfer HMS Hermes to the RAN during WWII prior to her loss to the Japanese
2. UK considered transferring or at least employing Australian crews on Implacable and Indefatigable
3. UK considered transferring a Colossus Class CVL (as part of a balanced squadron) to Australia
4. Australia initially planned to upgrade HMAS Sydney upon the delivery of HMAS Melbourne
5. The UK offered HMS Hermes (in her CTOL configuration) to Australia in the mid 60s :)
6. The RAN wanted the F-4J Phantom and lobbied for the acquisition of a modernised Essex to operate them.

7. Options besides a modernised Essex considered included a new build Essex or CV01

8. Australia was postulating a two ocean navy in the late 1960s and would require three carriers as part of this plan

9. HMS Hermes, Victorious and Eagle were all available at various points from the mid 1960s to the mid 1970s

10. Following the Falklands the UK proposed that Australia would build two replacement LSL for them following on from Tobruk and they would build us a modified Invincible in a barter deal
11. The cost of a replacement carrier (or, depending on the option selected, two) to operate the RANs existing Sea King and Wessex helicopters was less than the cost of buying the Seahawks and modifying the first three FFGs to operate them
12. Hermes / Viraat will likely remain in service in India until the mid 2020s
13. The RN determined that HMS Hermes could operate 20 Skyhawks in addition to AEW/COD Gannets, ASW Sea Kings and SAR Wessex.
As an aside, had Australia bought Hermes in 1968 how would the RN have faired in the South Atlantic in 1982 without her? Could Ark Royal have been retained longer to cover the gap?