The A-5 was developed after it was determined that the Fw 190 could easily carry more ordnance. The D-2 engine was moved forward another 15 cm (6 in), moving the center of gravity forward to allow more weight to be carried aft. Some A-5s were tested with the MW 50 installation: this was a mix of 50% methyl alcohol and 50% water, which could be injected into the engine to produce a short-term power boost to 2,000 PS (1,973 hp, 1,471 kW), but this system was not adopted for serial production. New radio gear, including FuG 25a Erstling IFF, and an electric artificial horizon found their way into the A-5. The A-5 retained the same basic armament as the A-4.The A-5 too, saw several Umrüst-Bausätze kits. The U2 was designed as a night Jabo-Rei and featured anti-reflective fittings and exhaust flame dampeners. A centre-line ETC 501 rack typically held a 250 kg (550 lb) bomb, and wing-mounted racks mounted 300 L drop tanks. A EK16 gun camera, as well as landing lights, were fitted to the wing leading edge. The U2 was armed with only two 20 mm MG 151 cannon. The U3 was a Jabo fighter fitted with ETC 501s for drop tanks and bombs; it too featured only two MG 151s for armament. The U4 was a "recon" fighter with two RB 12.5 cameras and all armament of the basic A-5 with the exception of the MG FF cannon. The A-5/U8 was another Jabo-Rei outfitted with SC-250 centreline-mounted bombs, under-wing 300-litre drop tanks and only two MG 151s; it later became the Fw 190 G-2. A special U12 was created for bomber attack, outfitted with the standard 7.92 mm (.312 in) MG 17 and 20 mm MG 151 but replacing the outer wing 20 mm MG-FF cannon with two underwing gun pods containing two 20 mm MG 151/20 each, for a total of two machine guns and six cannon. The A-5/U12 was the prototype installation of what was known as the R1 package from the A-6 onwards. The A-5/R11 was a night fighter conversion fitted with FuG 217 Neptun (Neptune) radar equipment with arrays of three dipole antenna elements vertically mounted fore and aft of the cockpit and above and below the wings. Flame-dampening boxes were fitted over the exhaust exits. 1,752 A-5s were built from November 1942 to June 1943.