F21 second proto HPA Contract CRD2601 CRD AAEE 11-43 G61 install (AAEE Aero Note was entitled 'Victor') Speed trials and positional error weights and CG loads. Thin section wing with extended tips metal ailerons u/c wheel doors for wells flush rivetted throughout ASTH 29-6-45 FACB 21-3-46 CE 13-4-46 (Note: not to be included in RAF strength) Serial was same as on Sunderland PP139