The Bendix K prototype in its second form, an unreal-looking egg shape. A print of this picture seems to be dated 27 November 1945. By January 1947 NX41817 was in its third form, with an open cockpit.

Bendix Helicopter was formed in 1943. The single-seat, coaxial Model K prototype, NX41817, first flew on 30 June 1945. NX41817 flew as a fully enclosed egg-shape apparently by November 1945 to aid the development of the bigger Model J. Although Bendix Helicopter based itself in Stratford, Connecticut, test-flying seems to have been done at Hadley Field in New Jersey.

A nice shot of D-IKNI, demonstrated in the USA by Gerd Achgelis. This is surely America - does anyone recognize the airport building? Achgelis arrived in New York by ship on 21 August 1936 and flew the Stösser to Los Angeles for an aerobatic display at the National Air Races.

The sole Do 18 converted with BMW 132 radial engines, probably seen on Lake Constance from where it first flew in this new Do 18L form on 21 November 1939. From January 1940 it underwent military testing at Travemünde coded CO-JF. The regular Do 18 suffered from its weak Jumo diesel engines but the more powerful radial in the pusher position gave cooling problems.

Dating approximate. D-IAGU is listed as a He 46F. It might be the prototype of the Armstrong Siddeley Panther-engined F variant. Only 14 series He 46F-1 and F-2s were built as unarmed observer trainers, whereas this aircraft is armed. Note the huge aerial masts.

1935 German Air Rally, the start or perhaps the finish at Tempelhof. Team C2 with five L 25ds was from Gleiwitz (now Gliwice) and took 13th place out of 30 teams. The teams had three to nine aircraft each for a total of 161 planes. 21 teams flew a total of 112 Klemms.

First flown in 1936 or 1937, the sole D-29 was built as a testbed for wing slats and split flaps. Fitted with T-tail to reduce downwash effects from these high-lift devices. Location not certain but this looks like a view from the north side of EDES.

The first prototype of the S-55, first flown on 10 November 1949. The S-55 was the first successful single-rotor helicopter capable of transporting significant loads. The key was to put the big piston engine in the nose, and the changeable payload and fuel in the centre of gravity. Initially 49-2012 had a half horizontal tailplane with endplate on this side instead of the two canted fins seen here. Print stamped June 1952.

Dedication of the new New York Municipal Airport, with aircraft of American, TWA, United and Canadian Colonial Airways in attendance. Commercial flights started on 2 December 1939. Floyd Bennett Field was too far from Manhattan. Campaigning for a new airport, mayor Fiorello La Guardia had refused to leave a TWA plane at Newark in New Jersey, arguing he had a ticket for New York.

'Inaugurating helicopter shuttle service for air mail between the New York airport and the 23rd Street Skyport Marina on the east side of Manhattan.' The chopper is the sole example of the GA-45D by G&A. Formerly Pitcairn Aircraft, this was a subsidiary of the Firestone Tire & Rubber Company, but by the time of this photo it had been renamed Firestone Aircraft.

This Breguet 941 was tested as the McDonnell Douglas 188 STOL airliner by Eastern Air Lines in 1968 and by American in the spring of 1969. Oddly it never carried a US registration and operated under its type-based French military serial number 2. It is interesting to note that this was a McDonnell and not a Douglas project, even though McDonnell felt more at home building fighters. Taken at the McDonnell factory at Lambert Field, this is assumed to be a McDonnell Douglas photo.

Contender for 1934 Challenge International de Tourisme. Note different landing gear compared to D-IJIP.

France produced an armada of large flying boat types. The prototype 01 of the four-engine Br 730 maritime patrol aircraft flew in April 1938 but crashed in July. This seems to be the first production machine, No 1, but confirmation is sought. No 1 was completed in Vichy French colours but not flown until December 1944 after the liberation of southern France. On one photo it seems to wear invasion stripes. This would be a later shot. The aircraft entered service as a transport, named Véga. It crashed in Arzew, Algeria in January 1949. Three more aircraft were completed, Sirius, Altair and Bellatrix, the latter two to Br 731 standard with a redesigned nose.

Engineer Alfred Verville left the US Army Air Service and joined the Buhl Aircraft Company where he designed the Airster three-seat open biplane. The CA-3A model had the distinction of receiving the first US type certificate, Approved Type Certificate 1. This example took part in the 1927 New York - Spokane Air Derby, flown by Nick Mamer. The National Air Races were held in Spokane, Washington, that year.

The prototype of the Bellanca Airbus, the sole P-100 airframe. Stamped August 1930, this press photo came with the announcement that the plane was to take part in the 1930 Ford Reliability Tour, but it appears that it was replaced by a Bellanca Pacemaker, NC257M, at the last minute, likely because its Curtiss Conqueror engine was unreliable. Converted to a P-200 Airbus with a Wright Cyclone radial. To Mexico in July 1931 as XA-BHO.

Neptunes for the Royal Air Force were allocated US Air Force rather than US Navy serials. When the aircraft were returned in 1957-58, many received a wrong serial. "51-15956" was really 51-15931, British serial WX505. To Brazil as FAB 7002. The real 51-15956 (c/n 5161), WX543, later to FAB 7000, returned as 51-15931. This is evidently not a 1951 delivery photo of 51-15956 as the aircraft had no MAD boom back then.

This was the Pioneer prototype, VL515, originally powered by a DH Gipsy Queen inline engine. Re-engined with an Alvis Leonides radial, it became a civil Pioneer II, G-AKBF, and then the first Pioneer CC.1 for the RAF, XE512, in 1953. Photo stamped July 1953. Delivered in August and immediately shipped to Malaysia for service with the Far Eastern Air Force. Crashed there on 4 November 1958.

The He 72 Kadett looks rather like the Fw 44 Stieglitz, but the main landing gear is very different and there is a strut supporting the tailskid. According to the German Wikipedia, He 72 production terminated in 1937 after 768 airframes, including 495 built by Fieseler. It also says that 629 Kadetts remained in Luftwaffe service in 1940, and 417 in January 1944. The Werknummer (c/n) on the tailfin looks like 426 in this and another photo but I'm not sure. It is certainly three-digit, which would indicate a Fieseler, not a Heinkel c/n. The badge belongs to Flugzeugführerschule A/B 24, wich was based in Olomouc, Czechia for most of WWII.

The He 172 was nothing more than a He 72 trainer with some aerodynamic improvements, notably a NACA cowling. The performance gain was disappointing and only two prototypes were completed in late 1935. It also seems that the Fw 44 Stieglitz was better liked than the Kadett by this time. Photo assumed taken in the winter of 1935-36.

This XH-39 set a new world helicopter speed record of 251 km/h (156 mph) on 26 August 1954. It was preserved at Fort Rucker in 1957. The S-59 was a heavily modified S-52 with a Continental XT51 turboshaft, developed from the French Turbomeca Artouste, and retractable landing gear.