US Navy resolves electromagnetic launcher issues
The issue of the U.S. Navy’s electromagnetic aircraft launch system (EMALS) causing too much stress on F/A-18E/F Super Hornet and EA-18G Growler aircraft outfitted with wing-mounted, 480-gallon external fuel tanks (EFTs), has been resolved.
According to an announcement from the U.S. Naval Air Systems Command, the Electromagnetic Aircraft Launch System (EMALS) team completed testing at Joint Base McGuire-Dix-Lakehurst, New Jersey, early this summer, validating a software fix that will ensure safe launches.
A total of 71 EMALS launches were conducted by the EMALS Team and the Air Test and Evaluation Squadron (VX) 23 to confirm F/A-18E/F Super Hornet and EA-18G Growler outfitted with wing-mounted, 480-gallon external fuel tanks (EFTs) can launch without exceeding stress limits on the aircraft.
The post-test review of aircraft instrumentation data, following the manned aircraft testing, indicates that software control algorithm updates have corrected the issue.
The issue was initially discovered in April 2014, when a review of aircraft instrumentation data following System Development and Demonstration (SDD) Aircraft Compatibility Testing revealed that holdback release dynamics exceeded current fleet allowances during launches of these aircraft configured with the wing-mounted EFTs.
While the aircraft met its programmed end speed and launched without incident, the post-test data analysis led to a deficiency report, which was cited as a concern in the annual Director, Operational Test and Evaluation (DOT&E) report on the USS Gerald R. Ford (CVN 78), the first to employ EMALS.
“We were confident since the day that the issue was uncovered that it was solvable,” said George Sulich, EMALS integrated program team lead. “The beauty of the system is that issues such as these can be accomplished with software updates instead of major hardware changes to machinery.”
He explained that the EMALS team promptly planned a resolution for further tuning of the system’s control algorithm, which would reduce the loads on the EFTs to within established operational limits. All design, development, software coding, laboratory testing and dead-load testing, using weighted, aircraft-representative sleds, was completed in 2015.
Since several other software updates had occurred since the fix was originally established, in April of this year, the team loaded the software build intended to correct the deficiency and conducted an additional 152 dead-load launches at the System Functional Demonstration Site to support flight test readiness.
The final step of testing the fix with instrumented aircraft launches was delayed a year due to competing test priorities, but is now complete, NAVAIR said. The subsequent software will be incorporated on board CVN 78 to support shipboard launches of F/A-18s with EFTs in 2019, following the ship’s post shakedown availability.
“Test is a time for discovery and while schedules often shift, the EMALS team has done excellent work to further improve the system’s controls software, eliminating concerns about undue stress to the aircraft, regardless of external fuel tank configuration, during launch,” said Aircraft Launch and Recovery Equipment Program Manager Capt. Stephen Tedford. “This small test victory gets us that much closer to launching an aircraft with a new technology aboard America’s newest aircraft carrier.”