Structural mods to extend US Navy Super Hornet service life

The United States Navy has awarded Boeing a US$73m (A$94m) contract to begin extending the service lives of its F/A-18E/F Super Hornet aircraft.
The service life modification (SLM) upgrade is a key element of the emerging Super Hornet Block III enhancement package, and will see the aircraft’s airframe life extended from 6,000 hours to more than 9,000 flight hours.
While details of the SLM upgrade weren’t revealed, they reportedly include various doublers, new material components and corrosion inhibitors installed across key structural areas of the aircraft. These enhancements are far subtler than the invasive centre-barrel replacement (CBR) program undergone by hundreds of US Navy and Marine Corps, Canadian and Australian F/A-18A-D classic Hornets last decade.
“The initial focus of this program will extend the life of the fleet from 6,000 to 9,000 flight hours,” Boeing SLM program director Mark Sears said.
“But SLM will expand to include Block II to Block III conversion, systems grooming and reset and O-level maintenance tasks designed to deliver a more maintainable aircraft with an extended life and more capability. Each of these jets will fly another 10 to 15 years, so making them next-generation aircraft is critical.”
Boeing has previously pitched the SLM process as an ideal time for the US Navy to begin the incorporation of other proposed Block III enhancements for the Super Hornet.
These proposed upgrades include but are not restricted to the installation of plumbing and mounts for upper fuselage conformal fuel tanks (CFTs), development of which was funded in mid-February, optical fibre wiring to support new generation sensors and weapons, the new Tactical Targeting Networking Technology (TTNT) datalink and Distributed Targeting Processor-Networked (DTP-N) computer, integration of the ALQ-214 Integrated Defensive Electronic Countermeasures (IDECM) Block IV EW suite, a new 10” x 19” large screen cockpit display, enhancements to the APG-79 AESA radar, and further improvements to the aircraft’s radar cross section.

Also funded and due to enter service in 2019 is a new centre-line auxiliary fuel tank which incorporates an upgraded Lockheed Martin AAS-42 infrared search and track sensor, dubbed IRST21 Block 2.
The first SLM Super Hornet is expected to be inducted into Boeing’s St Louis factory in April, while new-build aircraft incorporating the SLM enhancements will begin rolling off the line by the end of the year.
The US Navy operates 568 Super Hornets and about 120 Growlers, of which all but the first 130 F/A-18E/Fs are Block II aircraft which are equipped with a new forward fuselage with the APG-79 radar and other enhancements.