Software problems cause signal anomalies in HIMAR tests: Army

Taipei, May 26 (CNA) Two instances of "signal anomalies" during a recent test firing of missiles using the U.S.-made M142 high mobility artillery rocket system (HIMARS) were due to a fire control computer malfunction rather than Chinese signal jamming, the Army said Monday.

Army Chief of Staff Chen Chien-yi (陳建義) gave the assessment in response to concerns raised by a lawmaker during a legislative hearing that the system experienced signal anomalies during the recent test of the system.

Taiwan has purchased 29 of the latest HIMARS from the United States, and the first shipment of 11 was delivered in October 2024.

Taiwanese troops carried out the first live-fire test of the HIMARS system at the Jiupeng Base in the southernmost county of Pingtung on May 12. During the test, a total of 33 rockets were fired.

Chen told lawmakers that the signal anomalies on the day of the test occurred during the transmission of the firing command to the fire control computer, with the computer generating a self-diagnostic fault message.

Following standard operating procedures set by the U.S., the operator resolved the issue, and the launch was successfully carried out, he said.

After the test firing, however, Chen said the issue was quickly reported to the U.S. supplier.

It responded that the system's core functions remained intact and that the anomalies were mainly due to a "sporadic software issue" identified by the computer's self-diagnostic check, a problem found in the same software by the U.S. military and other user countries, Chen said.

Chen said a software update will be carried out as soon as possible, and it is not considered a problem with the entire system.

There have been concerns that the HIMARS multiple rocket system could potentially be subjected to GPS spoofing or interference by the Chinese military.

Concerns over the the HIMARS may not be unfounded. They were rendered "completely ineffective" when used by Ukraine because of Russian electronic jamming systems, the Washington Post reported in May 2024, citing a confidential Ukrainian weapons assessment, according to The Hill.

Russia electronic warfare capabilities caused the HIMARS to miss its target by more than 50 feet, the report said, though more recent accounts suggest HIMARS missiles have had more success, even if one system was recently destroyed by a Russian fiber-optic drone.

Chen said the recent test firing was conducted under comprehensive control protocols, which took into account the electromagnetic environment and the possibility of enemy signal interception.

He said the airspace, sea area, and electromagnetic environment were all considered as part of the safe firing procedures, and "no abnormalities were observed on the day of the test" in the general environmental circumstances.