Advanced Low Volume Ramjet

The ALVRJ (Advanced Low Volume Ramjet) was an experimental integrated rocket-ramjet cruise missile technology demonstrator developed by Ling-Temco-Vought and Texaco inc. for the US Navy for use on air and sea based assets. Development took place in the late-60s to early-70s with its first flight in 1974.

Development

The ALVRJ program was initiated by the Navy in 1968 under contract N0019-68-0605 with the purpose of demonstrating the flight characteristics and mission capability of an integrated rocket-ramjet missile. The missile was built around it’s integral booster, the low-volume ramjet propulsion system, which would activate after being launched by a solid rocket engine with a 5-second burn time. The ramjet would then repurpose the now empty rocket chamber as a ramjet combustion chamber using JP-5 fuel. Thus reducing the volume used for propulsion in the missile, hence: Advanced Low Volume Ramjet. The guidance system used on the ALVRJ was inertial with a proposed inertial/active radar homing package. In the 6 ALVRJ missiles built there was not a warhead present but rather a ballast that stabilized the missile and acted as a placeholder for the proposed high-explosive unitary warhead not completely dissimilar to the one in the AGM-78 Standard ARM.

Operational history

Throughout the 8 year lifespan of the program 6 Dynamic Test Vehicles (DTVs) (of which 5 were flown), plus ground testing equipment, were built to provide data for the improvement of the integrated rocket-ramjet system in the future. The first flight of the ALVRJ DTVs occurred in 1974. At the Program’s conclusion in 1976 all 5 flight tests resulted in a resounding success as the ALVRJ demonstrated a smooth transition from solid rocket-fueled engine thrust to ramjet thrust and stable cruise performance at both sea level and 35,000 ft (11,000 m), at speeds exceeding Mach 2.5 (1,918 mph, 3,087 km/h). In addition to this the missile demonstrated excellent controllability and satisfactory ramjet performance through lateral turns, pull-up, and nose-down maneuvers all with angles of attack expected in operations.

General info

• First flight: 1974

• Retired: 1976

• No. built: 6

• No. flown: 5

• Launch platform: A-7A, A-7E, F-4N
  • (Proposed): Sea based assets

Test Vehicle Specifications

• Length: 14.95 ft (4.56 m)

• Diameter: 1.25 ft (0.38 m)

• Wingspan: 3.31 ft (1.01 m)

• Weight: 1,500 lb (680 kg)

• Maximum speed:
  • At sea level: Mach 2.5 (1,918 mph, 3,087 km/h)
  • At 35,000 ft (11,000 m): Mach 3 (2,301 mph, 3,704 km/h)

• Maximum range (demonstrated):
  • At sea level: 28 nmi (32 mi, 52 km)
  • At 35,000 ft (11,000 m): 108 nmi (124 mi, 200 km)

• Service ceiling: >35,000 ft (11,000 m)

• Booster: Solid-fuel rocket
  • Burn time: 5 sec

• Sustainer: Ramjet
  • Fuel: JP-5

• Guidance: Inertial guidance
  • (Proposed): Inertial + Active Radar Homing (ARH)

• Warhead: Ballast for stability
  • (Proposed): High-explosive unitary warhead