McDonnell Douglas / BAe AV-8B / Harrier II
Aircraft
MD / BAe Harrier II
Type
Carrier-based fighter
Crew
1
Unit Cost
Unknown
Main Operator
USMC - RAF
Number Built
Unknown
Click here for all pictures of the Harrier currently available

AV-8B / Harrier II Program Milestones
Maiden Flight
T.B.A
Introduction
T.B.A
Retired
T.B.A
First User
United States Air Force


AV-8B / Harrier II Aircraft Dimensions
Wing Span
30 feet 4 inch (9.25 m)
Wing Aspect Ratio
4.0
Length
46 feet 4 inch (14.12 m)
Height
11 feet 7.75 inch (3.55 m)
Wing Area
230 sq ft

AV-8B / Harrier II Weights
Empty Weight
12,750 lb (5,783 kg)
Maximum Take-off Weight
29,750 lb (13,494 kg)
Maximum Landing Weight
19,400 lb (8,799 kg)
Fuel Capacity - Internal
7,500 lb (3,402 kg)
Fuel Capacity - Total
15,829 lb (7,180 kg)

Grumman F-14 Tomcat
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Grumman F-14 Tomcat

AV-8B / Harrier II Powerplant
RR Pegasus 11 Mk 103
21,700 lbf
AV-8B / Harrier II Radius & Performance
Range
1,200 nautical miles
Service Ceiling
N/A
Maximum Design Speed
Mach .89 (675 mph)
Maximum Rate of Climb
14,700 ft/min (210 m/s)
Thrust to Weight ratio
0.91

McDonnell Douglas AV-8B / Harrier

Related Aircraft /Articles
Thrust Vectoring // Vectoring in Foward Flight (VIFF)
McDonnell Douglas / BAe AV-8B / Harrier II
After the evolution of succesful air combat manoeuvring techniques, using VIFF (Vectoring In Forward Flight), initial excitement of the United States Marine Corps for the AV-8A (official designation by US Marine Corps) was intensified. Eventually its efforts to secure an enhanced version resulted in the first Anglo-American studies for an Advanced Harrier as long ago as 1973. Although this new version was already designated as the AV-16A (implies that this new version had twice the capabilities of the AV-8A) the British government opted out of a joint programme by declaring that there was "not enough common ground" between the US and UK requirements. Subsequently, McDonnell Douglas and Hawker Siddeley/British Aerospace pursued their own separate lines of development, both aimed at doubling the payload/radius capability of the Harrier/AV-8A without deviating too radically from the existing airframe/engine combination.

USMC AV-8B / Harrier
USMC AV-8B / Harrier
USMC AV-8B / Harrier
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Click for a large image...

First steps were taken by McDonnell Douglas and the US Marine Corps by modifying two AV-8As as prototype YAV-8Bs. The first of these two aircraft took of for the first time on 9 November 1978, and the second roughly three months later on 19 February 1979. The prototype demonstration was completed in the Summer of 1979 after both aircraft flew 185 test flights totalling 173 flying hours. During these test flights, the aircraft met or exceeded all performance requirements specified by the Marine Corps and Naval Air Systems Command.

The aim of the AV-8B, or Harrier as it is commonly known, is to achieve the improved performance capability required of the original AV-16A proposal by aerodynamic means, while retaining the same basic F402 engine, thus saving the cost of developing the Pegasus 15 originally considered necessary for the advanced version.

The American design features the use of graphite epoxy (carbonfibre) composite materials for the wings, and parts of the fuselage and tail unit, the adoption of a supercritical-section wing, the addition of lift-improvement devices (LIDS) comprising under-gun-pod strakes and a retractable fence panel forward of the pods, to augment lift for vertical take-off. Furthermore the design has larger wing trailing-edge flaps and drooped ailerons, a redesigned forward fuselage and cockpit, and redesigned air intakes in order to provide more VTO/STO thrust and more efficient cruise. The leading-edge root extensions, originally developed by British Aerospace have also been adopted as a standard, though heavily down-sized. This feature adds another four degrees per second to the AV-8B's instantaneous turn rate, enabling it also to meet the RAF's requirement for about 20 degrees per second. In order to cater for the higher operating weight and greater external stores loads, the landing gear is strengthened.

On the 12th of April 1979 four full-scale development AV-8Bs were ordered with the first aircraft taking-off three years later on June 4, 1982. The decision to take the Harrier into production was announced on 24 August 1981, at which time the British Ministry of Defence and the main industrial partners in the programme indicated initial requirements of 257 for the US Marine Corps and 60 for the RAF.

McDonnell Douglas / BAe AV-8B / Harrier II Design
The McDonnell Douglas / BAe aircraft is a single-seat V/STOL close support and reconnaissance aircraft and it specifically designed to meet this specific role. It is a cantilever shoulder-wing monoplane with low aspect ratio sweptback wings, non-swept inboard trailing-edges and small leading-edge root extensions. Compared to the AV-8A, span and area are increased by approximately 20 per cent. As stated earlier, the wings are fabricated as a one-piece structure, of mixed construction, with extensive use of graphite epoxy and other composite materials in the main multi-spar torsion box, ribs, skins, flaps, ailerons, LERX, and outrigger pods and fairings.

The fuselage is of the conventional semi-monocoque type which was generally similar to that of the AV-8A, but longer, due to the provision of a new forward fuselage built largely of graphite epoxy composite material. The centre and aft fuselage are mainly of aluminium alloy, except for forward and rear underfuselage heat shields, and a small area immediatly forward of the windscreen, which are of titanium. Lift-augmenting underfuselage devices consist of a fixed strake on each of the two ventral gun packs, plus a retractable fence between forward edges of the gun packs, just aft of the forward main landing gear unit. During VTOL modes the 'box' formed by these surfaces, which are made of composite materials, traps the cushion of air bounced off the ground by the engine exhaust, providing sufficient additional lift to enable the AV-8B to take off vertically at a gross weight equal to its maximum hovering gross weight.

The landing gear is a retractable bicycle type which permits operation from rough and unprepared surfaces of very low CBR. It is hydraulically actuated, with a nitrogen bottle serving as a back-up in case emergency extension is needed. The aircraft has a nose gear, retracting forward, twin coupled main wheels, retracting into the fuselage, and telescopic oleo-pneumatic main and outrigger gears.

The Harrier II is powered by one Rolls-Royce Pegasus 11 Mk 103 vectored-thrust turbofan engine. It produces approximately 21,700 lb of thrust and is supplied by redesigned engine intakes. The elliptical lip shape and re-inforced leading-edges protect the engines from bird strikes. Furthermore, fuel capacity is increased by enlarged integral fuel tanks in the wings, raising total internal fuel capacity to 7,500 lb. If necessary the aircraft can be refuelled through a retractable refuelling probe.


The McDonnell Douglas AV-8B has two under-fuselage gun/ammunition packs, mounting a five-barrel 25 mm cannon which is based on the General Electric GAU-12/U, with 300 rounds. Under each wing the aircraft stores three stations, with the inner one capable of carrying a 907 kg store, the centre one a 454 kg store, and the outer one a 286 kg store. The four inner wing stations are so-called 'wet', which permits the carriage of auxiliary fuel tanks. The maximum useful load for vertical take-off, including fuel, stores, weapons and ammunition, and water injection for the engine, is approximately 3,175 kg. For short take-off operations this weight is increased to 7,710 kg. Typical weapons for this type of aircraft include two or four AIM-9L Sidewinder or AGM-65E Maverick missiles, up to 16,500 lb general purpose bombs, 12 cluster bombs, ten Paveway laser-guided bombs, ten fire bombs, ten rocket pods, four chaff or flare pods, or two underwing gun pods. The main weapon delivery system for the AV-8B and GR.Mk 5 is the Hughes Aircraft Angle Rate Bombing System, mounted in the nose and comprising a dual-mode target seeker/tracker, linked to the HUD by computer.