Intended as a Standard Class 15m span single-seater to replace the popular Olympia, the EoN 463, also known as the EoN 460/463, was the production version of the EoN 460 and incorporated the design experience and certain features of the laminar flow Olympia variants, especially the Olympia 403 and 419.
The EoN 460, or Elliotts AP/10 Type 460 as it was also known, first flew in prototype form on 26 April 1960 and only the five prototype 460s were built; the first had an aspect ratio of 20 and an all-up weight of 600 lb, the second and third had an aspect ratio of 18 and an all-up weight of 630 lb, the fourth was the same as the first but with a modified one-piece canopy and the fifth prototype was the same as the fourth but had modified outer wing sections. The tail unit was very similar to the Olympia 419's and, as on the latter, the tailplane could be folded upwards for transport. The shoulder wings were set slightly lower than the Olympia's and the centre and forward fuselage were similar to the Olympia 419's, while the same NACA 64-series laminar flow wing section as on the 419 was used.
The production EoN 463 first flew in April 1963 and a total of 48 were built; this was practically the same as the fifth prototype 460, with an aspect ratio of 18 and an all-up weight of 630lb. The fabric and stringer top fuselage fairing of the 460 was now replaced by a glassfibre one on the 463, which also had a glassfibre instead of plywood nose section and a new cockpit canopy.
Both the 460 and 463 have wooden wings with light alloy spars, plywood-skinned and with overall fabric covering; the wings are similar to the Olympia 419's except for the reduced span, the Frise ailerons being fabriccovered and the DFS-type air brakes of plywood. The fuselage, like the 460's, is a wooden Warren girder type structure with plywood covering and a glassfibre rear fairing. The tail unit is a conventional fabric-covered wooden structure and the tailplane, unlike the all-moving surface of the Olympia 403 and 419, reverts to conventional elevators with a trim tab in the starboard one. There is a fixed unsprung mono-wheel with an internal expanding brake, and a tailwheel. The pilot's canopy has direct vision panels and a demister, and oxygen and radio can be fitted if desired.
The 463 was followed by the EoN 465, developed for the 1965 World Championships, only two of these being built, the first one, the Series 1, making its maiden flight on 8 March 1965. The 465 had the fuselage height reduced and the pilot seated in a reclining position to reduce cross sectional area and hence drag; the main landing gear skid was deleted and the monowheel centre raised. An all-moving tailplace was reintroduced which did not fold up for storage. The EoN 465 Series 1 had an all-up weight of 680lb and the second one, known as the Series 2, had a thinner wing section than the Series 1 and a strengthened main spar; its all-up weight was 700lb and wing area was increased to 140sq ft. Following the death of Elliott's managing director, Mr H. C. G. Buckingham, in the summer of 1965 the firm's board of directors, after reviewing the situation, decided to end glider production due to its increasing unprofitability.
Span:49 ft 2.5 in
Length: 21 ft 0 in
Height: 5ft 8 in
Wing area: 132 sqft
Aspect ratio: 18.0
Empty weight: 400 lb
Max weight: 630 lb
Max speed: 136 mph (in smooth air)
Min sinking speed: 2.2 ft/sec at 42.5 mph
Best glide ratio: 32:1 at 48 mph