[Graham Boak]

You can wrinkle a Spitfire's wing - or indeed most fighter's wings - by pulling too much g. You don't have to be vertical, or anywhere near it. However, in a steep dive the acceleration is such that you can readily exceed limiting speeds (and approach limiting altitudes!) and then have to pull the excessive g to recover. The Spitfire was an older design with a thin wing, which did not have the intrinsic strength of thicker sections. It was strengthened with the Mk.Vc, or universal wing, but experience with the pointed-wing Mk.VIIIs also lead to excessive wrinkling in air-to-air combat at lower altitudes. Despite its virtues elsewhere, the Spitfire was not an aircraft to go dive-bombing in.

Did pilots go vertical in the Typhoon - probably, although almost certainly less often than is claimed. Did this make them more accurate? Very doubtful indeed. If accurate dive-bombing was possible without airbrakes, then why did specialist aircraft have to have them?