Key Ministry of Defence officials have told MPs that the Carrier Strike programme is on time and on budget.
The Royal Navy’s largest and most powerful ships have cost £6.4bn.
Both Queen Elizabeth-class aircraft carriers, HMS Queen Elizabeth and HMS Prince of Wales, will require escorts in the form of a Carrier Strike Group when they deploy on operational duties.
Each Carrier Strike Group is likely to include Type 45 destroyers, Type 23 frigates, Royal Fleet Auxiliary ships, an Astute-class submarine and, in the longer term, Type 26 frigates.
Officials say the carrier programme provides highly capable assets, vital in projecting UK power around the globe.
However, there have been delays in a vital airborne radar system and three supply ships are years behind schedule.
The Ministry of Defence (MOD) has said it is confident HMS Queen Elizabeth will be operationally ready by the end of the year.
Nonetheless, some MPs on the Commons Public Accounts Committee remain sceptical.
When Labour MP Nick Smith asked if they had "over promised and underbought", Air Marshal Richard Knighton, the Senior Responsible Owner for Carrier Enabled Power Projection, said: "The short answer to that is no."
"Our intention is to grow this capability over a period of time," he added.
"By the time we get to full operating capability for Carrier Strike, which is the end of 2023, then we'll have sufficient aircraft and assets to be able to operate up to 24 aircraft on the carrier at a time."
The UK already owns 18 Lightning jets, with previous commitments to eventually buy 138 of the aircraft.
The MOD's most senior civil servant, Permanent Secretary Sir Stephen Lovegrove, however, stated, the 138 number was the "upper limit" of how many jets would eventually be purchased, but "more than 48", the current total order, would be bought.
Air Mshl Knighton said the remaining 30 F-35 jets on order will be delivered by 2025/26, adding that the plan to in future have 138 aircraft had been made under a backdrop where there were four operational F-35 squadrons and two Queen Elizabeth-class vessels deployed at all times.
It is now, however, more likely only one aircraft carrier will be deployed at once, with up to two operational Lightning squadrons.
Each squadron would consist of up to around 12 F-35Bs.
Air Mshl Knighton added that the number of aircraft the UK has by the end of 2025 "will be adequate to deliver those two squadrons".
He added: "If you want to pack a bigger punch and you want to thicken that force, then you will need more F-35s but that's a judgement around the overall size and shape of the Armed Forces which brings us back, I’m afraid, again to the Integrated Review."
The review was temporarily paused in April due to the coronavirus pandemic, but it resumed in June, with the Government inviting submissions of evidence last month.
The committee also heard the Crowsnest airborne radar system, designed to protect the carriers, is 18 months behind schedule.
Also, three supply ships, supposed to be delivered by 2026 won't be ready until the end of the decade leaving RFA ship Fort Victoria as the only supply ship for the Carrier Strike Group.
It led chair of the Commons Liaison Committee, Sir Bernard Jenkin, to ask whether the carriers were value for money.
Sir Stephen Lovegrove, said he had "no doubt" they were.
HMS Queen Elizabeth embarks on her first operational deployment in the New Year.