Did WW2 RAF Bombers have Airworthiness Certificates?

[Observer1940]

In an Archives I came across some 1940 British Government Load Sheets (released under the Public Record Act of 1958) which apparently indicate that the Bomb Load was increased from the maximum load stated by Armstrong Whitworth Aircraft the manufacturer of the bomber.

Then later the bomb load was increased yet again and all of the crew would need to be forward of the centre of gravity (CG), near/in the cabin when taking off. Certain aircraft manoeuvres could not be carried out until 400 gallons of fuel had been used.

I had to pinch myself (so as to speak) as I could not believe what I was reading

I presume that once an RAF bomb load exceeded the maximum load specified by the aircraft manufacturer, the aircraft would no longer have a Certificate of Airworthiness?

Although, it seems the RAF went to the RAE for testing and the aircraft bomb load was increased and therefore overturned the maximum manufacturer loading?

Mark

[Graham Boak]

I don't believe that British military aircraft have Certificates of Airworthiness,, as such. Their capabilities are assessed by the A&AEE at Boscombe Down (Martlesham Heath prewar) who then issue advice/instruction/limitations on their operation in the form of Service Clearances. These would normally be within the manufacturer's claims/statements, which were of course entirely driven by the requirements/specifications. If additional requirements arose (such as the need to carry more bombs/fuel) then these were assessed by further trials.

Other examples would include the Tallboy and Grand Slam (and Upkeep) on Lancasters, the various sizes of external fuel tank on Spitfires, and indeed any cases where the maximum t/o weight was less than that resulting from the maximum fuel and the maximum bombload - probably most bombers if not all.