Spitfire vs Me 109. Gallery . An american modified Spitfire IX. With two droppable tanks and a lot of more internal oil capacity. Two of them crossed the Atlantic in late 1944. This is really a matter to food a great "What if" thread. Wasn't it?
You forget, internal fuel capacity was also increased in these modified Spits - a 43 gallon tank was installed behind the pilot’s seat, and two leading edge tanks of 16½ gals each. IIRC, those tanks were problematic, and caused damage to the aircraft when dropped at speeds over 300mph.
Well, in fact i read in the web that the USAAF made more than this. Some thing like fill every space bigger than ten galons ... And increased the size of the rear tank (I recall it was in the Mk V too) to 340 l ... 90 Us Galons ... The tanks in the leading edge of the wings were in the MK VIII ... I guess the Mk Ix didn´t have them. The spitfire's evolution is impresive from the early Merlins to the Griffon ... from the range of the Mk II to the Mk VIII ... If there was any solution to prevent the damages the drop tanks caused ... whe arrive 74 years to late. I must say the "what ifs" look a bit irreverent for me: There was not "pause button" and they took their decissions the best they could. Other Pick . Israelite Mk IX with two tanks under the wings . Ferry flight .