By Sara Sirota / December 31, 2020 at 5:00 AM

The Joint Surveillance Target Attack Radar System program will soon begin testing a new key engine component and install updated pylons on the E-8C aircraft as part of a broader effort to mitigate the 1960s-era jet’s many sustainment challenges.

JSTARS met none of its annual aircraft availability goals and achieved its desired mission capability rate just once between fiscal year 2011 and FY-19, according to an audit the Government Accountability Office released in November. The report cited the E-8C’s TF33 engine as the primary readiness issue and pylon repair as a top driver of depot maintenance delays.

The Air Force previously considered replacing the engines, but since the Pentagon’s Cost Assessment and Program Evaluation office found in January 2019 continuing with the legacy TF33s offered the lowest cost and risk, the service decided to pursue a modification that could disable the engine’s thrust reversers.

The new lockout components have now successfully completed a fit check, Col. Patrick Maddox, senior material leader at Air Force Materiel Command’s intelligence, surveillance and reconnaissance division, told Inside Defense in a recent email. The program used aluminum parts to confirm the design since the final stainless steel parts have a relatively higher cost and longer manufacturing time.

Nevertheless, the stainless steel components are currently being manufactured and on-aircraft tests are scheduled for January, Maddox said.

According to GAO, JSTARS program officials also intended to begin a study to enhance the engine’s reliability and maintainability by the end of FY-20. While preliminary conversations between the government and original TF33 manufacturer have begun, a contract was not awarded in FY-20 because of budget and time constraints, Maddox said.

Meanwhile, the pylons that hold the E-8C’s engines to its wings require significant repair due to their age and issues at JSTARS prime contractor Northrop Grumman’s depot maintenance facility, GAO’s audit found. The program has worked with Northrop to fix these problems and partnered with Boeing to convert unused and improved KC-135 pylons so they could function on the E-8C.

Maddox said the modified pylons should be installed on JSTARS aircraft in the third or fourth quarter of FY-21.

The Air Force will add these systems, as well as other upgraded E-8C pylons, at a time when the program is overhauling its inspection and programmed depot maintenance strategy, which previously leveraged the commercial maintenance plan Boeing used for its 707 jets on which the JSTARS aircraft was based.

This plan called for one of four areas of the plane to undergo inspection and receive depot maintenance every two years, which program officials have deemed to be inadequate, according to GAO’s report.

The new approach, based on industry best practices, will instead have the E-8C undergo a full inspection every three years and depot maintenance every six years. This is expected to increase aircraft availability by about 16%.

According to Maddox, the updated inspection plan is currently under review, and once the Air Force validates it, the program will then look to verify the new programmed depot maintenance plan.

He said the JSTARS program is also still considering where it will perform depot maintenance, which is currently conducted at Warner Robins Air Logistics Complex, GA.

The Air Force had set up a collaborative maintenance speed line at the installation with Northrop and Boeing in 2018 to improve repair times, but this had to be shut down because of capacity constraints. GAO’s audit said program officials were working to reestablish the line at a Northrop facility, and Maddox confirmed Boeing’s involvement and that major structural work is slated to start in January.

The report also noted the JSTARS program began an organic depot maintenance proof of concept at Warner Robins but the two existing docks were insufficient for the full fleet, driving the program to request funding to build additional ones in FY-23. However, Maddox said no funding for the added dock space at the complex has been identified.