He 111 H-1 to H-10 training exercise, 10 October 1941 The H variant of the He 111 series was more widely produced and saw more action during
World War II than any other Heinkel variant. Owing to the uncertainty surrounding the delivery and availability of the DB 601 engines, Heinkel switched to
Junkers Jumo 211 powerplants, whose somewhat greater size and weight were regarded as unimportant considerations in a twin-engine design. When the Jumo was fitted to the P model it became the He 111 H. The He 111 H-1 was fitted with a standard set of three 7.92×57mm Mauser|
MG 15 machine guns and eight SC 250 or 32 SC 50 bombs. The same armament was used in the H-2 which started production in August 1939. The P-series was gradually replaced on the eve of war with the new H-2, powered by improved Jumo 211 A-3 engines of . This variant also differed from the H-3 in that it could either carry of bombs internally or mount one or two external racks to carry one or two bombs. As these external racks blocked the internal bomb bay doors, a combination of internal and external storage was not possible. A PVR 1006L bomb rack was fitted externally and an tank added to the interior spaces left vacant by the removal of the internal bomb-bay. The PVR 1006L was capable of carrying a
SC 1000 bomb. Some H-4s had their PVC racks modified to drop torpedoes. The H-5 series followed in February 1941, with heavier defensive armament. Like the H-4, it retained a PVC 1006 L bomb rack to enable it to carry heavy bombs under the fuselage. The first ten He 111 H-5s were pathfinders, and selected for special missions. The aircraft sometimes carried flashlight bombs which acted as
flares. The H-5 could also carry
heavy fire bombs, either heavy containers or smaller incendiary devices attached to
parachutes. The H-5 also carried LM A and LM B
aerial mines for anti-shipping operations. After the 80th production aircraft, the PVC 1006 L bomb rack was removed and replaced with a heavy-duty ETC 2000 rack, enabling the H-5 to carry the SC 2500 "Max" bomb, on the external ETC 2000 rack, which enabled it to support the bomb. Some H-3 and H-4s were equipped with
barrage balloon cable-cutting equipment in the shape of cutter installations forward of the engines and cockpit. They were designated H-8, but later named H8/R2. These aircraft were difficult to fly and production stopped. The H-6 initiated some overall improvements in design. The Jumo 211 F-1 engine of increased its speed while the defensive armament was upgraded at the factory with one
MG FF cannon in the nose and/or gondola positions (optional), two MG 15 in the ventral gondola, and one each of the fuselage side windows. Some H-6 variants carried tail-mounted MG 17 defensive armament. The performance of the H-6 was much improved. The climb rate was higher and the bomber could reach a slightly higher ceiling of . When heavy bomb loads were added, this ceiling was reduced to . The weight of the H-6 increased to . Some H-6s received Jumo 211F-2s which improved a low-level speed of . At an altitude of the maximum speed was . If heavy external loads were added, the speed was reduced by . Other designs of the mid-H series included the He 111 H-7 and H-8. The airframes were to be rebuilds of the H-3/H-5 variant. Both were designed as night bombers and were to have two Jumo 211F-1s installed. The intention was for the H-8 to be fitted with cable-cutting equipment and barrage ballon deflectors on the leading edge of the wings. The H-7 was never built. The H-9 was intended as a trainer with dual control columns. The airframe was a H-1 variant rebuild. The powerplants consisted of two JumoA-1s or D-1s. Many H-11s were equipped with a new PVC rack under the fuselage, which carried five bombs. Additional armour plating was fitted around crew spaces, some of it on the lower fuselage which could be jettisoned in an emergency. Engines were two Junkers Jumo 211F-2, allowing this variant to carry a load to a range of . Heinkel built 230 new aircraft of this type and converted 100 H-3s to H-11s by the summer of 1943.
Funkgerät (FuG) radio equipment. FuG 10P, FuG 16, FuBl Z and APZ 6 were fitted for communication and navigation at night, while some aircraft received the FuG 101a
radio altimeter. The H-16 retained its eight ESAC internal bomb cells; four bomb cells, as on previous versions could be replaced by a fuel tank to increase range. ETC 2000 racks could be installed over the bomb cell openings for external weapons carriage. Empty weight was and the aircraft weighed fully loaded for take off. German factories built 1,155 H-16s between the end of 1942 and the end of 1943; in addition, 280 H-6s and 35 H-11s were updated to H-16 standard. The last major production variant was the H-20, which entered into production in early 1944. It was planned to use two Junkers
Jumo 213E-1 engines, turning three-blade, Junkers VS 11 wooden-bladed
variable-pitch propellers. It would appear this plan was never developed fully. Though the later H-22 variant was given the 213E-1 engines, the 211F-2 remained the H-20's main power plant. Heinkel and its licensees built 550 H-20s through the summer of 1944, while 586 H-6s were upgraded to H-20 standard. In contrast to the H-11 and H-16, the H-20, equipped with two Jumo 211F-2s, had more powerful armament and radio communications. The defensive armament consisted of an MG 131 in an A-Stand gun pod for the forward mounted machine gun position. One rotatable
Drehlafette DL 131/1C (or E) gun mount in the B-stand was standard and later, MG 131 machine guns were added. Navigational direction-finding gear was also installed. The
Peil G6 was added to locate targets and the FuBI 2H blind landing equipment was built in to help with night operations. The radio was a standard FuG 10, TZG 10 and FuG 16Z for navigating to the target. The H-20 also was equipped with barrage balloon cable-cutters. The bomb load of the H-20 could be mounted on external ETC 1000 racks or four ESAC 250 racks. The sub variant H-20/R4 could carry twenty bombs externally. A batch of ten were produced and five were built from existing H-6s. The machines were joined by a center wing formed by two sections in length. The powerplants were five Junkers Jumo 211F engines producing each. The total fuel capacity was . This was increased by adding four drop tanks. With this load, the He 111Z had a range of and a speed of . The maximum bombload was . To increase power, the five Jumo 211F-2 engines were intended to be fitted with Hirth TK 11 superchargers. Onboard armament was the same as the He 111H-6, with the addition of one
MG 151/20 cannon in a rotating gun-mount on the center section. The layout of the He 111Z had the pilot and his controls in the port fuselage only. The controls themselves and essential equipment were all that remained in the starboard section. The aircraft had a crew of seven; a pilot, first mechanic, radio operator and gunner in the port fuselage, and the observer, second mechanic and gunner in the starboard fuselage. The He 111Z was to have been used in an invasion of
Malta in 1942 and as part of an
airborne assault on the
Soviet cities of
Astrakhan and
Baku in the
Caucasus in the same year. During the Battle of Stalingrad their use was cancelled due to insufficient airfield capacity. Later in 1943, He111Zs helped evacuate German equipment and personnel from the Caucasus region, and during the
Allied invasion of Sicily, attempted to deliver reinforcements to the island. During operations, the He 111Z did not have enough power to lift a fully loaded Me 321. Some He 111s were supplemented by rocket pods for extra takeoff thrust, but this was not a fleet-wide action. Two rockets were mounted beneath each fuselage and one underneath each wing. This added in weight. The pods were released by parachute after takeoff. Eight were shot down or destroyed on the ground in 1944. ==Production==