Components
Propulsion
All AGM-84 variants uses Teledyne CAE J402-CA-400 turbojet engine for propulsion. It weighs 100 lb (45.4 kg) and provides 600-660 lbf (2.67-2.94 kN) of thrust[1, 2, 3, 4, 5, 6]. Thrust specific fuel consumption is 1.2-1.58 lb/(h·lbf)[1, 2, 3, 5].
Early Harpoons used 100 lb (45.4 kg) of JP-5 fuel for propulsion[3, 6, 7, 8]. It was changed to denser JP-10 in AGM-84D, results in doubled range[6, 9, 10, 11, 12]. For the AGM-84H/K SLAM-ER, the fuel capacity has been increased to 132 lb (59.8 kg)[13].
Warhead
Harpoon and AGM-84E SLAM uses 488 lb (221 kg) WDU-18/B penetrating blast-fragmentation warhead containing 215 lb (97.5 kg) of Destex[14, 15, 16, 17, 18, 19, 20].
SLAM-ER uses 500 lb (226 kg) WDU-40/B penetrating blast-fragmentation warhead[14, 21, 22, 23, 24]. This new warhead features reduced explosive filling to 166 lb (75.2 kg) and a specifically shaped titanium case for more than twice of penetrating capability[14, 23, 25].
Seeker
Harpoon uses Texas Instruments AN/DSQ-28 guidance section with active radar seeker for terminal guidance[26, 27, 28, 29]. The seeker provides effective target acquisition and tracking up to sea state 5[30].
SLAM uses WGU-10/B imaging infrared seeker[16, 19, 31, 32, 33, 34, 35]. This was designed for common IIR seeker to many guided weapons like AGM-65D, GBU-15 and AGM-130[32].
Guidance
Harpoon rely on inertial navigation during midcourse guidance[36, 37, 38]. When the radar seeker finds a target, the missile descents to a sea-skimming altitude of 5-20 ft (1.5-6 m)[36, 37, 38, 39].
There are two terminal attack mode: pop-up and sea-skimming. Block 1 AGM-84A is pop-up only, Block 1B AGM-84C is sea-skimming only, and Block 1C AGM-84D is selectable between the two[9, 11, 12, 40, 41].
For SLAM, midcourse guidance is updated to the GPS-aided inertial navigation[16, 34, 35]. Thanks to the imaging infrared seeker from AGM-65D, it can be used against ground targets. However the SLAM’s maximum range is much longer than seeker’s acquisition range, it requires datalink to the launch aircraft for precision stand-off attack.
SLAM-ER presents better guidance, including terrain following capability and automatic target recognition feature[16, 34, 42].
Variants
AGM-84A Harpoon Block 1
Specifications
Length: 151 in (3.84 m)[7, 43, 44]
Diameter: 13.5 in (34.3 cm)[6, 7, 43, 44]
Wingspan: 3 ft (91.4 cm)[44]
Weight: 1,160 lb (526 kg)[7, 43]
Propulsion: J402-CA-400
Fuel capacity: 100 lb (45.4 kg)
Warhead: WDU-18/B
Guidance: inertial navigation + active radar homing
Maximum speed: Mach 0.85[6, 8]
Range: 60 NM (111 km)
Baseline model. Utilizes pop-up terminal attack mode.
AGM-84C Harpoon Block 1B
Upgraded version featuring lower cruising altitude.
Removed pop-up terminal attack mode for low altitude defense penetration.
AGM-84D Harpoon Block 1C
Specifications
Length: 151 in (3.84 m)
Diameter: 13.5 in (34.3 cm)
Wingspan: 3 ft (91.4 cm)
Weight: 1,200 lb (544 kg)[45]
Propulsion: J402-CA-400
Fuel capacity: 100 lb (45.4 kg)
Warhead: WDU-18/B
Guidance: inertial navigation + active radar homing
Maximum speed: Mach 0.85
Range: 120 NM (222 km)
Fuel has been replaced from JP-5 to JP-10, doubling range.
Terminal attack mode is selectable between pop-up and sea-skimming.
AGM-84E Standoff Land Attack Missile
Specifications
Length: 178 in (4.52 m)[13, 19, 43]
Diameter: 13.5 in (34.3 cm)
Wingspan: 3 ft (91.4 cm)
Weight: 1,366 lb (620 kg)[13, 19]
Propulsion: J402-CA-400
Fuel capacity: 100 lb (45.4 kg)
Warhead: WDU-18/B
Guidance: GPS-aided intertial navigation + datalink + imaging infrared homing
Maximum speed: Mach 0.85
Range: 50 NM (93 km)
Air-to-ground cruise missile variant, derived from AGM-84A[46].
Utilized WGU-10/B seeker from AGM-65, AN/AWW-13 datalink from AGM-62.
AGM-84H/K Standoff Land Attack Missile-Expanded Response
Specifications
Length: 172 in (4.36 m)[13, 19, 22]
Diameter: 13.5 in (342.9 mm)
Wingspan: 7.2 ft (2.19 m)[19, 22]
Weight: 1,500 lb (680 kg)[13, 19, 22]
Propulsion: J402-CA-400
Fuel capacity: 132 lb (59.8 kg)
Warhead: WDU-40/B
Guidance: GPS-aided intertial navigation + datalink + imaging infrared homing
Maximum speed: Mach 0.85
Range: 150 NM (278 km)
Modified SLAM with fold-out wing, new guidance section, improved warhead.
Sources:
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[22] SLAM-ER
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[29] Harpoon anti-ship missile
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[45] Boeing (McDonnell Douglas) AGM/RGM/UGM-84 Harpoon
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