(Reuters) - Raytheon Technologies (NYSE:RTX) Corp said on Friday the U.S. government has cleared its Pratt and Whitney unit to resume deliveries of its F-135 engine for the F-35 fighter jet, after a halt was put in place in December following the discovery of a safety concern.
The F-35 Joint Program Office said in a statement its engineers worked alongside Pratt & Whitney and Lockheed Martin (NYSE:LMT) to develop "mitigations for a rare system phenomenon involving harmonic resonance to develop a path forward for safe operation of the F135 in flight".
"The actions the government and industry team are taking will ensure incorporation of mitigation measures that will fully address/resolve this rare phenomenon in impacted F135 engines," it added.
The JPO also said the government was working on drawing up instructions for safely resuming flight operations for impacted and new production aircraft.
