Wind tunnel tests indicate that adding two 1500-litre conformal fuel tanks to the top of the Eurofighter Typhoon would extend the range by 25 percent without seriously hampering aerodynamic performance. This is seen as critical to reaching some markets (e.g., Australia) and to fully utilizing the Tranche-3 deep strike capability as it would free up two of the weapons stations (which are now used for external fuel tanks).--Stephen V Cole