Re 'Eurofighter FCS software to counteract Mach pitch-up' (Flight International, 7-13 May). For pitch-up it should read pitch-down, on all (no less than five) occurrences of the phrase. An astonishing error!

Chris Carpenter, RAF (Retd)

Sleaford, UK

Editor's note: Because of its configuration, Eurofighter, like other unstable canard fighters, suffers from pitch-up in the transonic regime. It is indeed the case that most aircraft "tuck under" as the flow becomes supersonic. Unfortunately, we had a limited space to explain rather a complicated phenomenon.

Source: Flight International