Alon X-A4 Aircoupe

Alon A-4 N6399X

The 1966 X-A4 Aircoupe was a prototypical four seat development of the A2.

One was built, N6399X, first flying on 25 February 1966. Priced at $11,000, it did not enter production.
Engine: 150hp Lycoming O-320A
Wingspan: 30’0″
Length: 20’9″
Useful load: 1107 lb
Max speed: 150 mph
Cruise: 140 mph
Stall: 52 mph
Range: 755 mi
Seats: 4

Air Capital Watkins SL-1

Watkins SL-1 NX470E

Designed by W C “Chet” Cummings, the Air Capital Watkins SL-1 NX470E was reportedly built as a marketing test project, priced at $2,750.

Watkins SL-1 NX470E

The title implies more of a funding organization than a factory, and is in all likelihood Watkins Skylark.

Engine: 60hp LeBlond 5D
Wingspan: 37’0″
Length: 23’6″
Seats: 2
Useful load: 480 lb
Cruise: 75 mph (with 30hp motor)
Stall: 35 mph

Vickers 618 Viking / Nene-Viking

The Ministry of Aircraft Production Air Ministry Specification 17/44 from Vickers-Armstrongs Limited. The specification was for a peacetime requirement for an interim short-medium haul passenger aircraft. To speed development the aircraft used the wing and undercarriage design from the Wellington but the fuselage was new. Although the original contract referred to Wellington Transport Aircraft, on completion, the name Viking was chosen.

Vickers 618 Viking Article

The initial 19 production aircraft (later designated the Viking 1A) carried 21 passengers, they had metal fuselages and – except for the wing inboard of the nacelles – fabric-clad geodetic wings and tail units. Following feedback from customers, the next 14 examples, known as, featured stressed-metal wings and tail units. The next variant, the Viking 1B, was 28 in (71 cm) longer than the Viking 1, carrying 24 passengers with up-rated Bristol Hercules piston engines, achieved a production run of 115.

The 107th airframe on the Weybridge production line was set aside, and the existing nacelles were replaced by completely new jet pods each housing a Rolls-Royce Nene, with the trailing edge of the wing extended at the rear to fair smoothly into the top of the pod. The Vickers main landing gears were of a totally new type, designed only for this aircraft, with four separate short legs each carrying a wheel which retracted to lie on each side of the jet pipe inside the nacelle. Unlike other Vikings the elevators were skinned with metal, and the metal skin on the wings and tailplane was made thicker than normal. There were also changes to the cockpit, fuel system and other items.

Chief test pilot J ‘Mutt’ Summers flew the Type 618 Nene-Viking from Wisley on April 6, 1948. At different times it bore civil registration G-AJPH and Ministry serial VX856.

On 25 July 1948, on the 39th anniversary of Blériot’s crossing of the English Channel, the Type 618 Nene-Viking flew Heathrow–Paris (Villacoublay) in the morning carrying letters to Bleriot’s widow and son (secretary of the FAI), who met it at the airport. The flight of 222 miles (357 km) took only 34 minutes. It then flew back to London in the afternoon. It obtained a maximum speed of 415 mph (668 km/h) at 12,000 ft (3,700 m) and averaged 394 mph (634 km/h). In 1954 it was bought from the Ministry of Supply and underwent the substantial conversion to Hercules 634 piston engines by Eagle Aviation to join their fleet as Lord Dundonald on September 24, 1954.

Engines: 2 x 2268kg Rolls-Royce Nene I turbojets
Wingspan: 27.2 m / 89 ft 3 in
Wing area: 81.93 m2 / 881.89 sq ft
Length: 19.86 m / 65 ft 2 in
Height: 5.94 m / 20 ft 6 in
Empty weight: 9548 kg / 21050 lb
Take-off weight: 15196 kg / 33502 lb
Max. speed: 753 km/h / 468 mph
Cruise speed: 632 km/h / 393 mph
Range: 555 km / 345 miles
Crew: 4

Ast Special / Mercury Air / ‘Shoestring’

In 1949 Carl & Vincent Ast, Van Nuys CA. built the Ast Special / Mercury Air midget racer ‘Shoestring’, designed by Rodney Kreimendahl. A single-place mid-wing monoplane.

First flown by Bob Downey, it won the 1951 Continental Trophy piloted by John Paul Jones and registered N26C.

It was restored in 1965 by Ray Cote with wing replacement in 1973 as N16V.

Plans were marketed, and several copies are known to have been built.

Engine: 85hp Continental C-85
Wingspan: 19’0″
Length: 17’8″
Max speed: 210 mph
Cruise: 180 mph
Stall: 65 mph

Askew M-3

The Askew M-3 of 1929 was a modified surplus Thomas-Morse Scout, two-place high wing monoplane.

Registered NX526K c/n 2-X, it first flew about 15 June 1929, powered by a 90hp Curtiss OX-5 engine.

The registration was cancelled on 10 July 1930 when CAA inspectors judged its workmanship as “very poor and dangerous.”