The Arado Ar 234 Blitz (Lightning) was the world's first operational jet powered bomber, built by the Arado company in the closing stages of World War II. In the field it was used almost entirely in the reconnaissance role, but in its few uses as a bomber it proved to be nearly impossible to intercept.
Background and prototypes
In early 1941 the RLM offered a tender for a jet powered high-speed reconnaissance aircraft with a range of 2150 km (1,340 miles). Arado was the only company to respond, offering their E.370 project, lead by Professor Walter Blume. This was a high-winged conventional-looking design with a Junkers Jumo 004 engine under each wing. The projected weight for the aircraft was approximately 8000 kg (17,640 lbs). In order to reduce the weight of the aircraft, and maximize the internal fuel Arado deleted the typical integrated landing gear and was to take off from a wheeled trolly and land via retractable skids.
Arado estimated a maximum speed of 780 km/h (485 mph), an operating altitude of almost 11,000 m (36,000 ft), and a range of 2,000 km (1,250 miles).
The estimated range was short of the RLM request, however they liked the design and ordered two prototypes as the Ar 234. The first two prototypes were largely complete before the end of 1941. However the Jumo 004 engines weren't ready, and wouldn't be ready until February 1943. When they did arrive they were only cleared for static and taxi tests, considered too unreliable by Junkers to be used for in-flight use. Flight-qualified engines were finally delivered that spring, and the Ar 234A-0 made its first flight on July 30, 1943. By September four prototypes were flying. Of what ended up being eight prototype aircraft to be fitted out with the original arrangement of trolley-and-skid landing gear, the sixth and eighth prototypes were powered with a quartet of BMW 003 jet engines each, the sixth having its engines housed in individual nacelles, and the eighth flown with them paired up in a single nacelle on either wing—the remaining ones were all Jumo 004 powered, with the V7 prototype destined to make history on August 2,1944 as the first ever jet aircraft to fly a reconnaissance mission.
The RLM had already seen the promise of the design and in July had asked Arado to supply two prototypes of a Schnellbomber version as the Ar 234B. Since the aircraft was very slender and entirely filled with fuel tanks, there was no room for a bomb bay and the warload had to be carried on external racks. The added weight and drag reduced the speed to "catchable" or at a 180 km (112 mile) limit so a set of 20 mm guns was added to a tail stinger for defence. Since the pilot had no view to the rear they had to be aimed through a periscope. The system was generally considered useless and many pilots had the guns removed.
The external bomb load made the skid-landing system impractical, so the bomber version was modified to have tricycle landing gear. The ninth prototype was the first Ar 234B, and flew in March 1944. The B models were slightly wider to hold the landing gear, and with added bomb load the plane would fly as slow as 660 km/h (410 mph). This was still better than any bomber the Luftwaffe had at the time, and made it the only bomber with any hope of surviving the massive allied air forces.
Production lines were already being set up, and twenty B-0 pre-production planes were delivered by the end of June. Later production was slow however, as the Arado plants were tasked with producing planes from other bombed-out factories hit during the Big Week. Meanwhile several of the A models were sent forward in the reconnaissance role. In most cases it appears they were never even detected, cruising around 460 mph (740 km/h) at over 30,000 ft (9,100 m).
The few B's entered service in the fall and impressed their pilots. They were fairly fast and completely aerobatic. The long takeoff runs led to several accidents; a search for a solution lead to improved training as well as the use of RATO, or rocket assisted takeoff. The engines were always the real problem; they suffered constant flameouts and required overhaul or replacement after about ten hours of operation.
Most of the B's were built as bombers, but the few recce versions of the B model flew more missions. Like all jet engines, the fuel consumption of the Jumos varied widely with altitude; at 10,000 m (32800 ft) it was a third of what it was at sea level. This meant that for low-altitude bombing missions the operational radius of the aircraft was only about 190 km (120 miles), while for high-altitude reconnaissance the range was as much as 720 km (450 miles) with drop tanks.
The only notable use of the plane in the bomber role was their use in the attempt to destroy the Ludendorff Bridge at Remagen. The aircraft continued to fight in a scattered fashion until Germany surrendered on May 8, 1945. Some were shot down in air combat, destroyed by flak (sometimes their own), or "bounced" by Allied fighters when they came in to land. Most simply sat on the airfields waiting for fuel which never arrived.
The standard bomb load was two 500 kg bombs suspended from the wings or one large 1000 kg bomb semi-recessed in the underside of the fuselage. If the war had continued it is possible it would have been converted to use the Fritz X guided bombs or HE-293 air-to-surface missiles.
Overall from the Summer of 1944 till the end of the war 210 total airplanes where built. In February of 1945 production was switch the C variant. It was hoped by November of 1945 production would hit 500 per month.
The AR 234C was equipped with four BMW 003A engines to free up Junkers Jumo 004s for use by Me 262. The utilization of four engines improved overall thrust, especially in take-off and climb-to-altitude performance. Additional airspeed was found to 20% faster with an increased range of 1,000 km. Although Hauptmann Diether Lukesch was preparing to form an operational test squadron, the AR 234C was not developed in time to participate in actual combat operations. There were two primary versions of the C, the C-1, a 4 engined version of the B-1, and the C-2, a four engine version of the B-2. At least seven other versions of the C were designed, or were in the planning stages before the war ended, these included bombers, armed recce, nightfighers and a heavy bomber. 14 prototypes of the AR 234C, which included the C-1 and C-2 models, were completed before the end of the war.
Powered by a pair of Heinkel - Hirth HeS-011A engines. No D's were constructed.
Two-seat night fighter versions, differing powerplant options and several options of radar. Several were in the planning stage, but none made it into production.
Only one Ar 234 survives today. The aircraft is an Ar 234 B-2 bomber variant carrying Werknummer (manufacturer's serial number) 140312, and was one of nine Ar 234's surrendered to British forces at Sola Airfield near Stavanger, Norway. The aircraft had been operating with 9./KG 76 (9th squadron, Bomber Wing 76) during the final weeks of the war, having operated previously with the 8th squadron. This aircraft and three others were collected by the famous "Watson's Whizzers" of the USAAF to be shipped back to the United States for flight testing. The aircraft was flown from Sola to Cherbourg, France on June 24, 1945 where it joined thirty-four other advanced German aircraft shipped back to the U.S. aboard the British aircraft carrier HMS Reaper. The Reaper departed Cherbourg on July 20, arriving at Newark, New Jersey eight days later. Upon arrival two of the Ar 234's were reassembled (including 140312) and flown by USAAF pilots to Freeman Field, Indiana for testing and evaluation. 140312 was assigned the foreign equipment number FE-1010. The fate of the second Ar 234 flown to Freeman Field remains a mystery. One of the remaining two was reassembled by the U.S. Navy for testing, but was found to be in unflyable condition and was scrapped.
After receiving new engines, radio and oxygen equipment 140312 was transferred to Wright Field near Dayton, Ohio and delivered to the Accelerated Service Test Maintenance Squadron (ASTMS) of the Flight Test Devision in July, 1946. Flight testing was completed on October 16, 1946 though the aircraft remained at Wright Field until 1947. It was then transferred to Orchard Place Airport, Park Ridge, Illinois, and remained at Orchard Place Airport until May 1, 1949 when it, and several other aircraft stored at the airport were transferred to the Smithsonian Institution. During the early 1950s the Ar 234 was moved to the Smitsonian's facility at Suitland, Maryland for storage, and eventual restoration.
The Smithsonian began restoration of Ar 234 B-2 140312 in 1984 and completed it in February, 1989. All paint had been stripped from the aircraft prior to the Smithsonian receiving it, so the aircraft was painted with the markings of an aircraft of 8./KG 76, the first operational unit to fly the "Blitz." The restored aircraft was first displayed at the Smithsonian's main museum building in downtown Washington D.C. in 1993 as part of a display titled "Wonder Weapon? The Arado Ar 234." In 2005 it became one of the first aircraft moved to the new Steven F. Udvar-Hazy Center near Washington D.C. Today 140312 is displayed next to the last surviving Dornier Do 335, an aircraft that had accompanied it on its voyage across the Atlantic Ocean aboard the Reaper over sixty years earlier.
General characteristics (Ar 234B-2)