FILE - In this Sept. 7, 2016 file photo, the future USS Zumwalt heads down the Kennebec River after leaving Bath Iron Works in Bath, Maine, on it's way to be commissioned. The Zumwalt, the most expensive... (Associated Press) 
 
 FILE - In this Sept. 7, 2016 file photo, the future USS Zumwalt heads down the Kennebec River after leaving Bath Iron Works in Bath, Maine, on it's way to be commissioned. The Zumwalt, the most expensive... (Associated Press) 
 
 PORTLAND, Maine (AP) — The most expensive destroyer ever built for the Navy suffered an engineering problem in the Panama Canal and had to be towed to port. 
 
 U.S. Third Fleet spokesman Cmdr. Ryan Perry said a vice admiral directed the USS Zumwalt to remain at ex-Naval Station Rodman in Panama to address the issues, which arose on Monday. The ship was built at Bath Iron Works in Maine and is on its way to San Diego. 
 
 "The schedule for the ship will remain flexible to enable testing and evaluation in order to ensure the ship's safe transit to her new home port in San Diego," Perry said in a statement. 
 
 USNI News, a publication of the U.S. Naval Institute, reported on its website that the ship was in the canal when it lost propulsion. Crew also saw water intrusion in bearings that connect electrical motors to drive shafts, the website reported. 
 
 USNI News also reported that the Zumwalt suffered minor cosmetic damage. The ship had been scheduled to arrive in San Diego by the end of the year to start the activation of its weapon system, the website reported. 
 
 The 610-foot-long warship has an angular shape to minimize its radar signature and is regarded as the most technologically sophisticated destroyer ever built for the Navy. One of its signature features is a new gun system that fires rocket-powered shells up to 63 nautical miles. 
 
 The Zumwalt cost more than $4.4 billion and was commissioned last month in Maryland. It also suffered a leak in its propulsion system before it was commissioned. The leak required the ship to remain at Naval Station Norfolk in Virginia longer than expected for repairs. 
 
 The ship is part of the first new class of warship built at Bath Iron Works in more than 25 years. 
 
 The second Zumwalt-class destroyer, which also cost more than $4.4 billion, was christened in a June ceremony during which U.S. Rep. Bruce Poliquin called it an "extraordinary machine of peace and security." The third ship is expected to cost a bit less than $3.7 billion. 
 
 A spokeswoman for Bath Iron Works said the shipyard was not planning to comment on the breakdown and deferred to the Navy. ||||| This post has been updated with additional information on Zumwalt’s casualty and repair schedule. 
 
 USS Zumwalt (DDG-1000) is pier side following an engineering casualty the ship suffered transiting the Panama Canal, U.S. Navy officials told USNI News on Monday. 
 
 The guided missile destroyer will undergo repairs at a former U.S. naval station until its fit to complete its journey to Naval Station San Diego, Calif., U.S. 3rd Fleet spokesman Cmdr. Ryan Perry told USNI News. 
 
 The ship was in the midst of a southbound transit through the canal when it suffered the casualty, Under orders from U.S. 3rd Fleet commander Vice Adm. Nora Tyson, Zumwalt is now stopped for repairs at the former U.S. Naval Station Rodman, he said. 
 
 “The timeline for repairs is being determined now, in direct coordination with Naval Sea Systems and Naval Surface Forces,” he said. 
 
 “The schedule for the ship will remain flexible to enable testing and evaluation in order to ensure the ship’s safe transit to her new homeport in San Diego.” 
 
 A defense official told USNI News on Tuesday the repairs could take up to ten days. 
 
 The ship lost propulsion in its port shaft during the transit and the crew saw water intrusion in two of the four bearings that connect to Zumwalt’s port and starboard Advanced Induction Motors (AIMs) to the drive shafts, a defense official told USNI News on Tuesday. The AIMs are the massive electrical motors that are driven by the ship’s gas turbines and in turn electrically power the ship’s systems and drive the shafts. 
 
 Both of the shafts locked during the passage and the transit had to be completed with tugs. The ship made minor contact with lock walls in the canal resulting in minor cosmetic damage. Following the transit, the Navy determined the ship couldn’t continue to its new homeport at Naval Station San Diego without additional repairs. 
 
 The latest casualty follows an incident in September following the ship’s transit from shipbuilder General Dynamics Bath Iron Works, Maine to Naval Station Norfolk, Va. in which the crew discovered “a seawater leak in the propulsion motor drive lube oil auxiliary system for one of the ship’s shafts,” the Navy told USNI News at the time. A service official told USNI News the most recent incident is similar. The service has narrowed down the likely problem to lube oil coolers leaking. The service replaced all four lube oil coolers following the September casualty. 
 
 Following its Oct. 15 commissioning, Zumwalt suffered additional unspecified engineering trouble around the time arrived at Naval Station Mayport, Fla. and spent extra time repairing and testing the propulsion system, USNI News understands. 
 
 Zumwalt entered the Panama Canal following a successful port visit to Colombia last week – a visit which the service intended to skip if it thought the engineering problems would continue, several defense officials told USNI News. 
 
 The ship’s engineering plant – the Integrated Power System (IPS) – is arguably the most complex and unique in the service. Installing and testing the system — that provides ship additional power margins to power high energy weapons and sensors — was a primary reason the ship delivered months late to the service. 
 
 Before the casualty, the ship was set to arrive in San Diego by the end of the year and start weapon system activation period before joining the fleet as an operational warship sometime in 2018. 
 
 Zumwalt is the first of three in the $22-billion class. Michael Monsoor (DDG-1001) and Lyndon B. Johnson (DDG-1002) are currently under construction at BIW.
– The Navy's new $4.4 billion "stealth destroyer" USS Zumwalt stealthily broke down in the Panama Canal this week, bumped into the lock walls, and had to be towed to port. The destroyer, which was on its way from Baltimore to San Diego, will now spend time at ex-Rodman Naval Station for repairs, reports the AP, which notes that the ship is the most expensive destroyer the Navy has ever had. According to the US Naval Institute, the Zumwalt suffered an "engineering casualty" while going through the canal. The ship lost propulsion during the incident and also suffered water intrusion to bearings that connect driveshafts to motors, reports USNI News. Officials say the problem is similar to one that the 610-foot ship suffered in September, when it lost propulsion on the way from Bath Iron Works in Maine, where it was built, to Baltimore, where it was commissioned in October. When it gets moving again, the Zumwalt will continue to Naval Base San Diego, where its futuristic weapon systems will be activated before it enters service in 2018. (The Navy can't afford ammunition for the destroyer's "Advanced Gun System.")