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During the last three days of the previous year, December 29th, 30th, and 31st, 1938, the two-seater Arado 79 touring aircraft set a new international distance record in a straight line for Class C light aircraft up to 4 liters total engine displacement in a 30-hour non-stop flight of 6300 km. This record has been submitted to the FAI for recognition. This achievement—covering a distance greater than that between Berlin and New York—has aroused such great admiration in expert circles that it warrants detailed discussion. The existing record of 4175 km was set last summer by the Czechs in a Tatra 101 (105 hp license-built Hirlh HM 504 engine) on the Prague-Khartoum route. When the Ar 79 set its first records over 1000 and 2000 km at the same time, it was a logical step for Arado to investigate whether the aircraft could also break and claim the international long-distance record in its class. The Ar 79 has the same engine, the HM 504 A 2, as the T 101. It differs primarily in its side-by-side seating and retractable landing gear. The top speeds are nearly identical at approximately 230 km/h. The D-EHCR, one of the three production aircraft released in the spring, was available for this purpose. It had already flown the Deutschlandflug (Germany Flight) in 1938 and set the international 2000 km speed record. The same model also holds the international 1000 m record and won the First International Air Races in Frankfurt am Main. Despite the wear and tear the D-EHCR had already endured, there were no concerns about using it for the planned undertaking. From the outset, the intention was to significantly exceed the Czech record by 50 percent.

To increase the standard range of 1025 km and to undertake such a long flight, a number of modifications and installations were necessary, which are relevant to characterizing the aircraft's performance reserves. The most important aspect was accommodating a sufficient fuel supply. Assuming a fuel consumption of 16 liters per hour in economy flight and a cruising speed of 160 km/h ground speed, taking into account headwinds and losses due to the necessary climb to high altitudes, over 600 liters of fuel had to be carried. The space occupied by the baggage compartment and the two standard 60-liter tanks beneath it was converted into a large fuselage tank. Its construction was only possible because the Ar 79 is built using a monocoque construction without bracing. The capacity of this tank was increased to 520 liters. However, this did not yet allow the Czech record to be broken by the intended amount. So the idea arose to mount an
external fuel tank under the center of gravity and main axis, its dimensions determined by the design of the Ar 79 and the requirements for D-EHCR. It held 106 liters. This auxiliary tank noticeably reduced the aircraft's speed, even though it fit snugly against the fuselage and was aerodynamically shaped as efficiently as possible, due to the increased frontal drag. To prevent the resulting loss from becoming too great, the external tank was designed to be jettisonable. After approximately five hours of flight, when the main tank was sufficiently empty to allow fuel to be pumped from the auxiliary tank into it, the tank was to be jettisoned. The pump and jettison lever were installed between the seats. The oil capacity was increased to 13 liters. The tank for this is located under the engine cowling.
Tailwheel with skid plate
Reverse. To enable takeoffs and landings even on poor and especially soft surfaces, the aircraft was fitted with a special tail skid. The tail wheel itself was retained. A skid plate was installed around the perimeter at axle height, which could be activated if the tail wheel sank in.

Since the baggage compartment had been lost, additional storage space had to be created. In front of the two seats are two boxes on which the crew members rest their knees. The left one serves to store the iron ration and food. The iron ration itself consisted of dried fruit, chocolate, one hundred cigarettes, and hard bread. Food items such as fruit and lean meat were taken from Benghazi onward. The right knee box contains flares with the corresponding pistol, a revolver and ammunition, as well as a small set of tools.

Drinking water was carried in two rubberized linen bags, each holding four liters, between the main fuel tank and the fuselage wall. The side walls of the cabin had six pockets for the extensive map material for the flight from Brandenburg to Bangkok. Maps were available for most of the route.
Empty weight............. 520 kg
Equipment.............. 26 kg
Fuel................ 464 kg
Oil................. 13 kg
Crew and other payload . . . . , 167 kg
Maximum takeoff weight for the record leg . . . .1190 kg

Therefore, the Ar 79 had to take off for the record leg with almost exactly its own weight in fuel. The decisive factor for the permissible payload was primarily the strength of the landing gear. The static calculations showed that it could withstand the load. Also important was the question of maintaining sufficient stability, especially around the lateral axis. It was determined that this was sufficient without causing excessive fatigue to the crew through constant, arbitrary corrections. The rigidity of the aerobatic aircraft and the performance of the Hirth engine were, moreover, found to be sufficient.

The Crew
The aircraft's crew consisted of First Lieutenant Pulkowski and Lieutenant Jenett. First Lieutenant Pulkowski, a former aircraft engineering student, known for an African flight two years prior, which we reported on extensively at the time, is 30 years old and a member of the paratroopers in Stendal. It was a coincidence that he inquired with Arado at the same time as the record attempt was being planned, inquiring whether an aircraft could be made available to him for a new long-distance flight. Lieutenant Jenett has only recently joined the Air Force. He was formerly a medical student. He is 24 years old and has experience in instrument flying.

Choosing the flight path at this time of year was difficult. A north-south route was out of the question due to the significant temperature differences—risk of icing and, on the other hand, the formation of thunderstorms. Consequently, the route was chosen to run from west to east. Tripoli was selected as the starting point.

Since a flight of approximately 6,000 km would inevitably lead to the area around Benares in northern India, it was decided to combine the record attempt with a long-distance flight of over 50,000 km. The intention was to showcase the Ar 79, which had already garnered considerable international attention due to its previous achievements, to a large number of countries. The record route itself was developed in cooperation with the Reich Air Ministry, the Aero Club of Germany, the Hamburg Naval Observatory, and other organizations.