Paul Lewis/WASHINGTON
The US Navy is considering two antenna options for the proposed Northrop Grumman E-2C Hawkeye Radar Modernisation Programme (RMP), plus it is planning to test a hybrid rotating electronically scanned array and a more advanced fixed UHF electronically steerable array (UESA).
Initial RMP work has focused on a space-time adaptive system to counter clutter in littoral areas. The ADS-18 antenna comprises 18 elements mounted on a 21-channel rotary coupler. The system, like the E-2C's mechanically scanned APS-145, rotates within the E-2C's 7.3m (24ft) diameter rotodome.
UESA is a more advanced but less defined RMP option funded as a science and technology programme in parallel with ADS-18, and would be housed in the same dome. UESA would be non-rotating. The 54-channel system would give the E-2C an expanded theatre missile defence capability and could be either a follow on to ADS-18 or a single step solution depending on the outcome of testing, says Cdr Jim Clifton, USN E-2C deputy programme manager.
The USN is planning to conduct a mountain top test of the system at its Pacific missile range on Kauai Island during 2002. The USN is installing ADS-18 on a Lockheed Martin EC-130V for flight testing in 2002, after which the UESA could than be retrofitted to the Hercules testbed.
The results of this test and a risk assessment of the technology will determine the route RMP will follow when engineering and manufacturing development is launched, intended for 2003. "If UESA works it goes into RMP, if not we have ADS-18. Another possibility is to do both with an interim ADS-18 solution," says Clifton.
Northrop Grumman and the USN are seeking funding for RMP to begin in 2003, a start date that would mean the upgrade radar could be in service by 2010.
Meanwhile, the US Navy has flown an E-2C with an NP-2000 eight-bladed propeller. The composite-bladed, digitally-controlled propeller will replace the four-blade metal unit which equips USN E-2Cs and Northrop C-2A Greyhounds. Carrier suitability trials are due for the third quarter of this year and fleet introduction for late the next.
The eight-bladed propeller is one of a number of measures to improve the maintainability of the Hawkeye. Other changes include a modular power distribution system.
Source: Flight International
