This post has been updated to include additional information.

Surface escorts from the Harry S. Truman Carrier Strike Group left their homeports today to kick off an overseas deployment.

Aircraft carrier USS Harry S. Truman (CVN-75) did not.

After the carrier was sidelined at the end of August with a malfunction in the ship’s electrical distribution system, engineers continue to assess the problem. “The aircraft carrier’s repairs are progressing, and all efforts are being made to deploy the carrier and air wing as soon as possible,” according to a Navy statement to USNI News.

The timeline for diagnosing the problem and fixing it remains unclear.

In the meantime, the surface ships in the strike group are forming their own surface action group and deploying with neither the carrier nor the air wing.

Arleigh Burke-class guided-missile destroyers USS Lassen (DDG-82) and USS Farragut (DDG-99) departed Mayport, Fla., today, and will be joined by Norfolk-based USS Forrest Sherman (DDG-98) and Ticonderoga-class guided-missile cruiser USS Normandy (CG-60) in the coming days.

The SAG will be led by the Destroyer Squadron (DESRON) 28 and her staff, along with elements of the carrier strike group staff. The SAG staff brought in about 15 additional personnel to make up for capabilities typically found on the carrier, particularly in the areas of maintenance and technical support, U.S. 2nd Fleet Commander Vice Adm. Andrew Lewis told USNI News today in a telephone interview.

The SAG will also take with it a detachment of MH-60R helicopters from Helicopter Maritime Squadron (HSM) 72 out of Naval Air Station Jacksonville, Fla.

“This group is going to deploy more than likely to multiple regions, and they are going with a much higher-end capability, with helicopter detachments with significant anti-submarine warfare capability, significant air defense capability, as well as strike warfare capability,” Lewis said.

“So really a full-up group, minus the carrier and the air wing. But a full-up, very capable group is going off to do the nation’s bidding in this great power competition.”

Lewis said this is the first time a SAG has deployed from the East Coast since 2006 and admitted it was an unusual and unfortunate situation to send a SAG in lieu of a full carrier strike group. But, he said, his job as a fleet commander is to be flexible and put forward the most warfighting capability with the assets available to him.

“The situation with Truman frankly is unfortunate; obviously we’re working really hard to fix it and we will fix it, but it’s unfortunate – nobody wanted that to happen certainly. But we’re going to make this into what it really is, which is, we’ve still got a massive capability that’s going forward on time, and that will be even more amplified when Truman comes out.”

Having a carrier strike group deploy without an aircraft carrier is a largely unprecedented move by the service. Several former Navy officials who spoke to USNI News pointed to past instances where a carrier was stuck in maintenance or otherwise unable to deploy on time, and another carrier in the fleet was able to swap in and take its place. When USS Dwight D. Eisenhower (CVN-69) didn’t leave the yard on time for its 2015 deployment, Truman went in its place, for example.

However, the ongoing maintenance backlog in the East Coast’s aircraft carrier fleet leaves the Navy with no ready aircraft available to sub in for Truman, if needed.

The one example of a CSG sending its escorts out ahead of the carrier occurred with the Nimitz CSG in 2013. USS Nimitz (CVN-68) had an emergent maintenance issue arise in November 2012, so its destroyers deployed in January 2013 and the carrier was in maintenance until March, rejoining the DDGs that were operating as a SAG in the Pacific.

Lewis said the carrier brings the deterrent effect, but the cruiser and destroyers bring the most in-demand naval capabilities.

“If you look at the missions that are in demand by naval forces, by high-end naval forces, much of them can be classified in the maritime security operations, anti-surface warfare and anti-submarine warfare. There’s no doubt the carrier and the embarked air wing brings amazing strike capability and deterrent capability wherever it goes, but short of that, this is really going a long way towards the kind of capability we need to have at sea that can go across all mission sets. It’s highly maneuverable – not just physical maneuver but maneuverable in the spectrum of conflict, from everything from peacetime day to day steaming to fighting the big fight. So it’s a very capable group.”

“There’s no question that not having the aircraft carrier, it does detract from the symbolism and the deterrent effect, no question. The aircraft carrier is a behemoth beast with an amazing capability that, it shows up off your shores, and if you’re not our friend you become our friend quickly if you know what’s good for you. There’s no question that that effect is lost with smaller ships, but these ships are really really capable,” he continued.

As for the fate of the carrier, Lewis said engineers are beginning repairs and continuing to assess the full damage to the electrical system.

“They’re in the process of repairs and identifying all the root causes that they can at this point. There’s still some unknowns, frankly, but we’ve got some of the worlds best engineers on it, between the Naval Sea Systems Command, Naval Reactors and the waterfront here. So I am pretty confident that they will fix it and make sure there’s no redundancy left at the pier when she pulls away from the pier,” he said.

“We fully intend to deploy the aircraft carrier at a later time. We obviously can’t talk about that timeframe right now and what it’s going to be right now, but we’re pressing forward with that and it will deploy and rejoin the group at some point. So it goes to the dynamic capability of maritime forces.”

Asked for a ballpark of how much longer the repair would could take, Lewis said, “I can’t say because I don’t know.”

The Truman Strike Group deployed for most of 2018, and in early July it began a Composite Training Unit Exercise (COMPTUEX) to re-certify for a second deployment during the sustainment phase of the Optimized Fleet Response Plan, when strike groups remain at high readiness in case they are called on to surge forward in a crisis or to carry out a planned second deployment or participate in an overseas exercise.

Even without the carrier and air wing, “we have an important mission ahead,” Capt. Jennifer Couture, commodore of Destroyer Squadron 28, said in the Navy news release.

“SAG operations allow the Commander tremendous flexibility and responsiveness in the types of missions that can be conducted, and geographic reach into varied and diverse areas. The SAG ships are ready and able to support a variety of exercises and missions with our partners and allies in support of maritime stability and security around the globe.”

The SAG includes about 1,200 sailors and, after having gone through COMPTUEX, is certified to conduct high-end combat operations, routine patrols, maritime security operations, and theater security cooperation activities to enhance regional security and stability, according to the news release.

Though this SAG deployment is not being planned and executed under ideal circumstances, Lewis said he’ll be looking for lessons learned to inform future SAG operations from the East Coast.

Noting that the Truman CSG conducted the first “Dynamic Force Employment” deployment last year by bucking tradition and operating in the Arctic instead of the Middle East, “this is just another branch of the Dynamic Force Employment, and there’s going to be other opportunities” to stretch the concept too.

“This is going to open a lot of doors to doing things differently in order to be operationally unpredictable to our competitors, in order to impose cost or keep them on their toes, but strategically predictable that we will be where we need to be, whether to exercise or be postured or be operating with the capability that we need to have in order to execute the mission, and strategically predictable to our partners, to our allies, and indeed to ourselves,” the admiral said.