Faulty resistors to blame for stalled production of US Navy anti-radiation guided missile

Faulty resistors have stalled production on the US Navy’s Advanced Anti-Radiation Guided Missile (AARGM), causing delays in future deliveries of the weapon. A fault in a batch of resistors installed on circuit card assemblies has been pinpointed as the cause of the issues.

The tiny resistor is made by a sub vendor to Cobham, which provides radiofrequency (RF) processors to Orbital/ATK, the prime contractor for AARGM, IHS Jane’s 360 reported.

The resistors are commercial off-the-shelf (COTS) components purchased from a qualified supplier that has never had problems with its resistors before, Captain Al Mousseau, program manager for Direct and Time Sensitive Strike Weapons (PMA-242), told IHS Jane’s on 21 April.

There are four circuit card assemblies in an AARGM RF processor, with a total of 199 resistors, some of which are stacked resistors and others stand-alone. And there are different failure modes, he said.

Captain Mousseau added that to date the navy has been able to track all of the weapons concerned, and that so far only two ARRGMs, already in place with an air wing, have serial numbers that match those with the low-yield resistors.

“They are good weapons, but our concerns are more on the service life. Once the opportunity presents itself, we will swap those two weapons out,” he said.

He explained that the RF processor is the brains of the system, enabling the AARGM weapon system to perform its mission. In mid-February, Orbital/ATK informed the navy that Cobham had just reported lower than expected yields on its RF processors. According to the captain, the entire notification process between Cobham and Orbital/ATK and Orbital/ATK and the USN occurred in a 24-hour period.

“Orbital [notified us] they had paused production at Cobham until the engineering investigation was completed,” Captain Mousseau said.