Roden 1/72 Heinkel HE-111E Emil 027

The pre-production E-0 series were built in small numbers, with Jumo 211 A-1 engines loaded with retractable radiators and exhaust systems. The variant could carry 1,700 kg (3,700 lb) of bombs, giving it a takeoff weight of 10,300 kg (22,700 lb). The development team for the Jumo 211 A-1 engines increased power to 690 kW (930 hp), subsequently the He 111 E-1s bomb load capacity increased to 2,000 kg (4,400 lb) and a top speed of 390 km/h (240 mph).[28]

The E-1 variant with Jumo 211A-1 engines was developed in 1937, the He 111 V6 being the first production variant. The E-1 had its original powerplant, the DB 600 replaced with the Jumo 210 Ga engines.[29] The more powerful Jumo 211 A-1 engines desired by the Ministry of Aviation were not ready; another trial aircraft, He 111 V10 (D-ALEQ) was to be fitted with two oil coolers necessary for the Jumo 211 A-1 installation.[29]
He 111E of the Legion Condor

The E-1s came off the production line in February 1938, in time for a number of these aircraft to serve in the Condor Legion during the Spanish Civil War in March 1938.[30] The RLM thought that because the E variant could outrun enemy fighters in Spain, there was no need to increase the defensive weaponry, which would prove to be a mistake in later years.[29]

The fuselage bomb bay used four bomb racks but in later versions eight modular standard bomb racks were fitted, to carry one SC 250 kg (550 lb) bomb or four SC 50 kg (110 lb) bombs mounted nose up. These modular standard bomb racks were a common feature on the first generation of Luftwaffe bombers but they limited the ordnance selection to bombs of only two sizes and were abandoned in later designs.[29]

The E-2 series was not produced and was dropped in favour of producing the E-3 with only a few modifications, such as external bomb racks.[28] Its design features were distinguished by improved FuG radio systems.[30] The E-3 series was equipped with the Jumo 211 A-3s of 820 kW (1,100 hp).[30]

The E-4 variant was fitted with external bomb racks also and the empty bomb bay space was filled with an 835 L (184 imp gal; 221 US gal) tank for aviation fuel and a further 115 L (25 imp gal; 30 US gal) oil tank. This increased the loaded weight but increased range to 1,800 km (1,100 mi). The modifications allowed the He 111 to perform both long- and short-range missions.[31] The E-4's eight internal vertically aligned bomb racks could each carry a 250 kg (550 lb) bomb.[32] The last E Variant, the He 111 E-5, was powered by the Jumo 211 A-3 and retained the 835 L (184 imp gal; 221 US gal) fuel tank on the port side of the bomb bay. Only a few E-4 and E-5s were built.[30]

The RLM had acquired an interest in rocket boosters fitted, for the sake of simplicity, below the wings of a heavily loaded bomber, to cut down the length of runway needed for takeoff. Once in the air the booster canisters would be jettisoned by parachute for reuse. The firm of Hellmuth Walter, at Kiel, handled this development.[33] The first standing trials and tests flights of the Walter HWK 109-500 Starthilfe liquid-fueled boosters were held in 1937 at Neuhardenberg with test pilot Erich Warsitz at the controls of Heinkel He 111E bearing civil registration D-AMUE.[34]