Two former Royal Air Force chiefs and a former Tory defence minister have condemned a cost-cutting decision to ditch a vital special forces aircraft as "perverse" and "extraordinary".
In a letter to The Times newspaper, also signed by other senior ex-commanders, they warned that the removal of the last of the 14-strong fleet of C-130J Hercules planes this month will leave a capability gap at a time of rising security risks.
A newer, larger fleet of aircraft - the Atlas A400M - is taking over the role but the RAF has admitted there will be temporary gaps in niche capabilities required by special forces.
Concerns have also been raised about the availability of the A400.
In their letter, Air Chief Marshal Sir Michael Graydon, Air Chief Marshal Sir Richard Johns, Sir Gerald Howarth and the other signatories wrote: "Of the many cuts to our armed forces in recent years, one of the most perverse is the disposal of the RAF's remaining 14 C130 transport aircraft.
"At a time of great international tension, the decision to remove a proven and effective workhorse is extraordinary."
In an exclusive Sky News report last month, defence sources warned the UK will be left
"dangerously exposed" when it cuts its C-130 fleet.
Internal documents revealed that the A400M was still plagued by problems, with two-thirds of the fleet listed as unavailable for flying missions in early May.
Three C-130 planes will conduct a farewell flypast across the UK on Wednesday.
The last public appearance of the iconic aircraft will be as part of a flypast on Saturday for the King's birthday. The RAF is selling the fleet to other nations as the aircraft still have years of flying time.