On 6.2.1919 all Dolphins were grounded. Mod 271 was agreed a week later. In the interim the Dolphins were to be flown straight and level only. In the case of 81 Squadron/ 1 Squadron, Canadian Air Force, this work was not carried out, and so flying restrictions remained until the movement to Shoreham on 1.4.1919 and conversion to SE 5as.

Anyone know was Mod 271 was or the specific problem it was designed to address ?