The Heinkel He 177 LSP — The Flying Launch Pad of the Third Reich

By late 1943, as Germany’s war effort strained under relentless Allied pressure, the Luftwaffe began diverting resources toward experimental “Wunderwaffen” — miracle weapons that might still turn the tide. Among the more obscure of these was a special conversion of the heavy bomber Heinkel He 177, known as the He 177 LSP (Luft-Start-Plattform) — an aircraft designed not to bomb cities or ships, but to carry and launch a rocket-powered plane from the sky.

The LSP project emerged from the development of the DFS-346, a radical, high-speed experimental aircraft conceived by the Deutsche Forschungsanstalt für Segelflug (DFS). The rocket plane was intended to reach 30,000 meters altitude and exceed the speed of sound, serving as a prototype for a future long-range reconnaissance aircraft. However, its extreme performance required it to be launched from the air rather than from the ground — and that’s where the Heinkel engineers entered the story.

Design and Conversion

In January 1944, Heinkel received the order to modify one He 177 A-5 to act as the Luft-Start-Plattform. The conversion was extensive. The entire tail section was redesigned with twin vertical fins, allowing the DFS-346 to be mounted on the aircraft’s spine without interfering with the rudder controls.

All defensive armament — the ventral gondola, upper turret, and tail guns — was removed to save weight and to provide space for monitoring instruments. In their place, engineers installed telemetry receivers, pressure sensors, flight recorders, and two control stations that would monitor the rocketplane during its release and climb phase. The bomb bay was reconfigured to house power generators and additional fuel tanks, ensuring the He 177 could reach high altitude with its precious payload.

Painted in a dull gray camouflage and bearing only minimal markings, the He 177 LSP became one of the most unique aircraft ever built by the Reich.

Flight Testing

The modified bomber made its maiden flight from Rechlin in March 1944. Despite its ungainly silhouette — a heavy bomber topped with a sleek rocketplane — the test pilots reported surprisingly stable flight characteristics. Engineers from DFS and Heinkel worked side by side to refine the coupling mechanism and separation system.

After several weeks of unpowered drop simulations, the time came for a live launch.

On June 11, 1944, the He 177 LSP took off from Rechlin with the first DFS-346 V1 mounted above its fuselage. At the controls of the LSP was Oberleutnant Franz Kellner, while the rocketplane was piloted by Hauptmann Erich von Süder. Escorted by two Bf 109 fighters and a He 111 with film cameras, the aircraft climbed over the Baltic Sea north of Rügen to an altitude of 7,000 meters.

At 13:23, the clamps released. For a brief moment, the massive Heinkel was jolted by the loss of weight, then steadied as the DFS-346 fell away, ignited its rocket, and shot upward. The LSP crew tracked the aircraft through its radio feed and confirmed the data: the DFS-346 had exceeded Mach 1.1, making it the first manned supersonic flight in history — though the feat remained a closely guarded secret.

Continued Service

Over the next six months, the He 177 LSP served as the workhorse for all subsequent DFS-346 flights. It conducted six launches in total, all from Rechlin and Peenemünde. Engineers improved the coupling structure and added a reinforced dorsal fairing to handle the stress of carrying the rocketplane at high speed.

By December 1944, the rocketplane program had produced valuable aerodynamic data, but tragedy struck during a landing accident that destroyed the DFS-346. Without another test article ready, the LSP was grounded.

In April 1945, as Soviet troops advanced into northern Germany, the He 177 LSP was evacuated to Leipzig-Mockau, where it was captured intact. Soviet engineers immediately recognized its unique configuration, shipping the aircraft to the USSR for examination.

Soviet Afterlife

In Soviet records, the aircraft appeared under the designation “He 177S – Samolyot Nositel” (Carrier Aircraft). It was tested in early 1946 as a potential mothership for new high-speed rocket research vehicles. Although the concept was later replaced by the Tu-4 “mother ship” system, the Heinkel’s launch configuration heavily influenced Soviet air-launch research through the late 1940s.

Legacy

Only one He 177 LSP was ever built, but it symbolized one of the Luftwaffe’s last technological leaps — the transition from conventional bombers to air-launched, high-speed research vehicles. Its partnership with the DFS-346 marked Germany’s first real attempt to merge rocketry and aviation into a single weapon system — a concept that would later define both Cold War space programs.