The reasons are outlined in a Warships IFR of April 2018. The piece is written by Graham Edmonds “How to Avoid a Clash of Cultures and Operational Needs Hampering UK Carriers”
As background info I understand the plan is to standup 2 x FAA Sqdns and 2 RAF.
I’m unable to link however in summary:
Pilot currency in operating from carriers is vital and were RAF Sqdns not to routinely embark major deficiencies will occur because currency requires not only operational flying from the carrier but also equal time in a simulator.
In the Joint Force Harrier time statistics show that RAF embarkation time in carriers were low.
This not only effects pilots but ground crews also.
The on watch off watch embarkation plan between the four squadrons raises further operational and administrative differences, flying from sea operates from a different set of rules. There are no diversion airfields, the airfield/carrier is not in the same place from take off to landing and the scenery is unrelentingly unchanging.
Harmony rules differ between the services. RN personnel can be separated from home for up to 9 months, the RAF from between 3 & 4 months.
A question in the House of Lords enquired if Harmony rules for RAF persons serving in the new squadrons will be brought into line with the RN, answer, RAF Harmony rules will apply.
This lack of joint ness means that in a carrier deployment of 9months the embarked RAF chaps could be changed mid deployment at least once even twice.
This undermines the maintenance of operational capability, in the Harrier days RAF pilots on 3 month detachments rarely achieved a night flyingcapability, in the final years of the last Ark Royal’s strike carrier deployments the number of RAF pilots who qualified for Full Weather operations was very low if not nil.
Under these rules a surge to three embarked squadrons and then to be fully qualified is almost impossible without lengthy qualifying periods beyond the present administrative rules.
The shortcomings become readily apparent when the facts are laid bare.
Easy fix
Ban moustaches on warships.
The UK have such a long history of aviation at sea and the ships to carry them,that it's difficult to believe that these obvious lessons have not being learnt, and that this major capital investment of QE11 class aircraft carriers and F35B aircraft will be restricted by such tribal nonsense.
Give the Navy its planes, pilots and maintainers and let them excel at what they do best.
Protect the task force and project at distance the will of the government on an international stage.
No disrespect to the RAF they have other roles to perform.
Regards S