HAV 304

Surveillance Vehicles

HAV 304 (21 Days Continuous Flight)

Title of the picture


Long Endurance Multi-Intelligence Vehicle (LEMV). A specific function surveillance hybrid air vehicle. The vehicles derive their flight capability from a mix of aerodynamic lift and Helium buoyancy.


Laminated fabric construction hull with internal catenary system supporting the payload module. The hull’s aerodynamic shape, an elliptical cross-section allied to a cambered longitudinal shape, provides up to 40% of the vehicle’s lift. The internal diaphragms required to support this shape allow for a limited amount of compartmentalisation further enhancing the fail-safe nature of the vehicle. Multiple ballonets located fore and aft in each of the hulls provide pressure control.

Landing System

Profiled pneumatic tubes on the underside of the two outer hulls provide an amphibious capability. Tubes are ‘sucked-in’ for a clean-in-flight profile. System shares use of ballonet fans with hull pressure system.

Power Plant

4 x 350 hp 4 litre V8 direct injection, diesel engines. Supercharged induction system. Two engines mounted forward on the hull and two on the stern of the hull for cruise operation. All four are configured in ducts with blown vanes to allow vectored thrust for take off/landing/ground handling operation.

Payload Module

Located on centerline; comprises 3 primary areas as follows:

Flight Deck:

  • 1 pilot station.
  • Single pilot control.
  • Large transparencies for excellent all-round visibility.
  • FCS
  • Payload compartment.


  • Universal load beam.


  • Fuel tanks

Flight Controls

Optionally Manned,Remotely piloted,Autonomous

Principal Data
20,000 ft for 21 days
Envelope Volume: 38,000 m³ (1,340,000 ft³)
Overall Dimensions:
- Length: 91 m (300 ft)
- Width: 34 m (113 ft)
- Height: 26 m (85 ft)
Endurance: 21+ days
Altitude: 20,000 ft
Speed: Cruise 80 KTAS
Loiter: 20 KTAS
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+44 (0)1234 336400

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