FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1971
1971 - 0061.PDF
IF YOU HAD TO PICK THE TWO AEROPLANES in British military service which have the greatest number of apparent similarities, the choice would likely fall on the Phantom and the Buccaneer. There are similarities too in their histories. First flights were within a month of one another in early 1958 and both are naval aeroplanes which later found themselves in Air Force service. Both are twin-Spey powered, two-seat and radar equipped. Dimensions, empty weights and internal fuel capacity are within a few feet of a 60ft X 40ft span and length, within a few hundred pounds around 30,5001b and within 50 gallons around l,600gal. Not too surprising if they are to fit (and, the way things usually are, only just fit) on a British aircraft carrier. The list continues with the a.c. generation systems, use of three-axis autostability, the emphasis placed on angle-of- attack indication and, more exclusively, the immersion of a large part of their wing areas in high-pressure boundary- layer blowing. But from here on the list dries up, the disparities dictated by their very different fighting roles begin to emerge and reveal the superficial nature of some of the apparent similarities. In the Phantom the Spey is reheated, in the Buccaneer it is not. Though wingspans and areas are similar, the planforms, thickness/chords and aspect ratios are far from it. These two features, the wing and the power available, considerably influence the way in which the boundary-layer blowing is applied. The low-level strike role of the Buccaneer naturally emphasises low fuel consumption and consequently rules out the idea of reheat. The wing planform is a compromise between the low-aspect-ratio dictates of gust response and the high aspect-ratio required by range performance. By contrast, the Phantom sacrifices all to its Mach 2-plus intercepter performance, making no great compromises with other rdles but rather adapting its supersonic neces- *Deputy chief test pilot and project engineer, HSA Holme-on-Spalding Moor. Blow, blow thou BLC wind By J. G. BURNS and M. EDWARDS* sities to its take-off and landing performance. The key components are reheat and a thin near-delta wing. The Spey 201's unblown unreheated thrust is 12,2501b, 54.6kN, and rises to 20,5001b, 91.5kN,with reheat. Boundary- layer blowing for take-off drops this to a quite acceptable 17,2001b, 76.6kN. At take-off in the basic intercept role the weight is 44,0001b, 20,000kg, and the thrust/ weight ratio is a respectable 0.8. It is logical to exploit this potential by rotating the thrust-vector and the easiest way to do that is to lengthen the nosewheel leg. In a classic end-of- the-fuselage reheat installation the nozzles would scrape the deck before a worthwhile ground angle was reached, unless the mainwheel legs in turn were lengthened. The Phantom gets around this by placing the nozzles about half-way between the wing trailing edge and the end of the fuselage, the lower outline of which is thereafter sharply cut away. This distinctive shape, now shared by Jaguar (on a copie la Fantome?), is undoubtedly "dirty" when the reheat is off, and combines with the unfavourable influences of the reheat installation in making a major contribution to an unsensational cruise performance. When the burner is lit, however, the picture changes. The twin cones of the massively increased jet efflux now blend closely with the sculptured underside of the rear fuselage and the Phantom
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
