The lead ship of the US Navy’s new class of aircraft carriers, the USS Gerald R. Ford (CVN 78), will return to operations three months later than originally planned, in part due to issues related to ship’s nuclear propulsion plant.

News of the delay comes amid the confirmation of a US Navy plan to retire the Nimitz-class aircraft carrier USS Harry S. Truman earlier than scheduled by canceling the ship’s planned mid-life overhaul.

The delay to Ford is caused in part by extensive repairs to main turbines generators that are powered by the ship’s nuclear reactors, according to a USNI News report.

The turbine generator repairs are likely related to earlier propulsion issues related to a recent design change which forced the ship to return to port in May 2018.

Navy acquisition chief James Geurts told the HASC’s seapower and projection forces subcommittee.

“All three of those causal factors – making the adjustments to the nuclear power plant that we noted during sea trials, fitting in all of the post-shakedown availability workload and finishing up the elevators – they’re all trending about the same time. So, October right now is our best estimate,” USNI News reported Navy acquisition chief James Geurts as saying.

Every new ship undergoes a post-shakedown availability (PSA) after going through a test and evaluation period. During the availability, contractors repair or improve the design of the ship in preparation for final contractor trials.

While CVN 78 is the first new US aircraft carrier design in 40 years and identifying problems with the ship’s design and systems is part of the evaluation process, officials are still concerned with some of the brand new systems installed on the lead ship in the class.

In its latest report, the director of operational test and evaluation (DOT&E) identified poor or unknown reliability of the newly designed catapults, arresting gear, weapons elevators, and radar. All these systems are critical for flight operations and DOT&E noted they could affect the ability of CVN 78 to generate sorties, make the ship more vulnerable to attack, or create limitations during routine operations.