Avro Type 720
For a description of the format and data included in Production Tables, see here.
Contents
Type Description
- Type 720
- Rocket propelled single seat delta wing interceptor fighter to Specification F.124T to meet the requirements of OR.301. It was constructed of metal honeycomb sandwich, with both wing and fin being multi-spar structures. The aircraft featured a tapered delta planform with a thin section and a 60-degree angle of sweep on the leading edge, as did the the fin. The trailing edge of the wing carried two pairs of control surfaces: inboard elevators and outboard ailerons. Retractable airbrakes were provided above the rear fuselage. The circular-sectioned fuselage tapered from a thin pointed nose to a rear end that surrounded the rocket-motor orifice. The canopy faired into a dorsal sine that ran to the fin leading edge. A tricycle undercarriage was fitted, the nosewheel retracting rearwards into a bay aft of the intake within the ventral ducting, while the main wheels retracted forwards, with the oleos turning through 90 degrees to allow the wheels to lie flat within the thin-sectioned wing. The aircraft's main armament was to comprise a pair of de Havilland Firestreak air-to-air missiles carried on under-wing pylons; however, air-to-air rockets in the form of sixty-four 2in unguided rockets, set within a centre section ventral bulge containing four sixteen-rocket packs, as requested originally in F124T, or two cannon, were available as alternative weapon loads. Initially designed to be purely rocket-powered with one 8,000lb thrust Screamer rocket motor, it was subsequently revised under Specification F.137D to permit the introduction of a supplementary 1,640 lb thrust Bristol Siddeley Viper turbojet, the latter housed in a ventral duct running from an intake positioned below the cockpit, to an exhaust outlet below the wing trailing edge.
A significantly redesigned Type 720 design was proposed to Specification F.177 to meet the requirements of OR.337. It was now primarily powered by a de Havilland Gyron Junior turbojet a deeper fuselage, with a chin intake, along with a one 8,000lb thrust Spectre rocket motor, and featured a V-shaped windscreen, area ruling to its fuselage, a notched wing leading edge and an airborne intercept (AI) radar in its nose, which increased the overall length to 45ft.
| Type 720 Specification | |||||||||
| Span | Length | Height | Wing Area | Empty Wt | Max AUW | Cruise Speed | Maximum Speed | Range | Service Ceiling |
| 27 ft 4 in | 42 ft 3 in | 360 sq ft | 7812 lb | 17575 lb | 1320 mph/ 1147 kn | 60000 ft | |||
| 8.33 m | 12.88 m | 33.45 m2 | 3543 kg | 7972 kg | 2124 km/h | 18288 m | |||
Projected Variants
- Type 725
- Advanced trainer to Specification T.147 to meet the requirements of Air Staff OR.318 and Admiralty requirement NA.45. Derived from the Type 720 with a new, side by side seating cockpit, but the remainder of the structure unaltered. Initially intended to be powered the same as the Type 720, this was later replaced by solely turbojet propulsion, either the Bristol BE.26R (later to become the Orpheus), or the proposed de Havilland DH.10, though the latter was replaced by the Gyron Junior. Armament was to consist of a single 30mm ADEN cannon, mounted externally on the port side of the fuselage, plus a variety of underwing stores.
- Type 726
- Single engined light interceptor/escort fighter variant of Type 720. Armament consisted of two 30mm ADEN cannons in the wing roots, plus either RP pods or Blue Jay missiles on underwing pylons. One de Havilland PS.37 or Armstrong Siddeley P.151 powerplant, with re-heat on the interceptor variant only.
- Type 727
- Single seat NATO ground attack aircraft based on the wing of the Type 720, which now featured only one set of elevons rather that seperate ailerons and elevators. Armament was to be two 30 mm ADEN cannon, or four 12.5 mm Browning machine guns, along with two 500 lb or 1000 lb bombs. One 4,850 lb. thrust Bristol Orpheus powerplant, fed by cheek intakes.
- Type 728
- Mixed power Naval interceptor, probably to meet Admiralty requirement NSR/NA.47. Naval version of later Type 720, with one de Havilland Gyron Junior plus Spectre rocket motor. A larger, un-notched wing of 460 sq.ft. was to be fitted, along with a longer stroke undercarriage
Production Details
| Serial Range | C/n | Batch Qty |
Conv. | Canc'd | Notes |
| 2 aircraft ordered from A.V. Roe & Co. Ltd., Chadderton, to contract 6/Acft/9354. Cancelled. | |||||
| XD696, XD701 | 2 | Cancelled. See Note 1. | |||
| Total Production | 2 | ||||
Production Summary
All Aircraft By Type
| Type | Built New | Conv | Canc'd | Total |
| Type 720 | 2 | 2 | ||
| 0 | (0) | 2 |
Notes
- The extremely well finished mock-up of the Type 720, shown with serial XD696, has, over the years, given rise to the assumption that this was the partially complete first prototype. This was not the case, and although construction of the prototype had begun, no aircraft was completed before cancellation in 1957.
Production References
- British Experimental Turbojet Aircraft, Barry Jones (The Crowood Press, 2003)
- British Secret Projects 3: Fighters 1935-1950, Tony Buttler (Crecy, 2018)
- Teach for the Sky, James Jackson (Hikoki. 2021)
- Project Cancelled, Derek Wood (Janes, 2nd Ed., 1986)
- British Experimental Jet Aircraft, Barrie Hygate (Argus Books, 1990)
Page Revision History
Revised at Version 2.0.0- Moved from Low Production to a new page.
- Improved Type Description and Added Specification details.
- Added Projected Variants