The U.S. Navy’s Orca drone, also known as the Extra-Large Unmanned Undersea Vehicle (XLUUV), has been in development for years, but will soon be in the hands of sailors as the sea service works to figure out how they will use the capability going forward. The Navy first ordered five of the semi-tractor trailer-sized submersible drones from Boeing Defense in 2019. But like other Navy acquisition programs, the Orca has been hit by cost increases and delivery delays.
Still, 2025 is shaping up to be a big year for the Orca, which is based, at least in part, on lessons learned from Boeing’s Echo Voyager demonstrator. While a so-called Orca “test asset system” drone was delivered to the Navy in late 2023, its getting its first real Orca this year. That will be followed by the Navy’s operational testing and evaluation of the platform in the coming months, which will allows the Navy to further test and refine the platform before eventually joining the fleet for real-world operations. The development comes as unmanned underwater vehicles of all sizes are increasingly viewed as a potentially providing a revolution in undersea warfare among friends and foes alike, with China, in particular, pursuing the technology aggressively.
To discuss where Orca stands, and where it could potentially go in a future that is trending more toward unmanned systems everyday, TWZ chatted with Capt. Matt Lewis, a submariner and program manager for the Navy’s Unmanned Maritime Systems office. Lewis shared his thoughts on the service’s premiere submarine drone, its present and future capabilities and the unique challenges drones face operating in an undersea domain, among other topics.
This interview has been edited for grammar, length and clarity.
Geoff: When you think about Orca’s capabilities, and what you’re aiming to have it add to the fleet? Can you provide a potential future scenario in which you think Orca’s capabilities would excel?
Capt. Lewis: Initially, as designed, the system is to deliver CDMs, clandestine-delivered mines. So that’s the initial purpose, in response to a fleet need that came out several years ago. And so that’s the initial concept of how we would use Orca.
I don’t know if you’ve ever seen any pictures, to give a sense of scale, but this is a pretty large vehicle, a large system, and so I’m pretty confident that the payload capacity, the carrying capacity, or the volume that the vehicle has probably outmatches anything out there, at least that I know of. And so, while designed to carry CDMs, if you took that kind of space and weight, that payload section, one could conceptualize how we use that for other devices, other missions, other payloads, and employ it in that way.
It’s 84-feet-long. It’s actually a little longer, I think, than a standard semi, you know, the 18-wheel tractor-trailer. So it’s a pretty significant vehicle, and calling it a vehicle doesn’t really feel like it gives it justice, right? Because it’s pretty big.
Geoff: So it sounds like it’s created to sneak into somewhere and lay some mines and then move on. But it also sounds like that capacity could be used for other things in the future as well, right?
Capt. Lewis: You’re exactly right. It could be just carrying it from point A to point B. It could be leaving something somewhere. It could consider a kinetic or non-kinetic payload. I don’t want to say it’s endless because it’s not that. It’s not that easy. It’s easy to think of things, but it’s not necessarily that easy to design them and build them.
One of the things that makes this really challenging, though, is that operating in the undersea domain is a lot more complex than some of the other domains. One of the complexities of trying to do anything like this is water depths, and so whatever you need to bring in has to be built for that environment, right? So as you operate in the water column, I mean, we saw it in the news with the [the civilian Titan submersible that imploded in 2023], the system that went down to go see the Titanic, that’s an extreme measure of the complexity of operating undersea.
But those are the sorts of things that have to also be considered when we talk about payloads. So it’s not as easy as, ‘oh, I can bring this thing in, and I can go at 6,000 meters deep’ … That payload needs to be encapsulated, sustained, under that sort of pressure. And when we start talking about those cool, science-fiction ideas, it becomes a lot more challenging technically.
Geoff: When we talk about other [future Orca] payloads, are you talking about launching smaller undersea drones, surface drones, air drones? Is any of that definitively on or not on the table, as the Orca is getting ready to join the fleet?
Capt. Lewis: Some of the devices or payloads you mentioned, whether it’s a UAV or a UUV or other things like that, I would say the Navy is open and considering those types of payloads. But we need to get the Orca capability, the Orca system, into the hands of the fleet, and there’s a lot of learning that we have to do with these. There is a lot of learning that we have ahead of us, and so what I’m focused on is getting the vehicle out into the hands of the sailors, and go do that part.
Geoff: Just for our non-submariner readers out there, can you just walk me through in laymen’s terms what makes it harder to do [drone operations] in an undersean [domain]? Is it just a matter of transmitting signals to the Orca? What makes autonomous operations under the sea harder?
Capt. Lewis: One of the big things is communication. On the surface and in the air, you have the ability to have 24/7 connectivity with a device. You have that ability to do that in the surface and air domains.
Once you go underwater, you have that air-water interface to manage, and so with that comes a latency of command and control and information data flow from that system. So the submariners are used to going out and being in receive-only, where we communicate off the ship very little. And that has all the decision making and the power of the human brains all underway with it.
When you talk about a UUV, some of that decision making, some of that information that people or commanders may want now, has to break that air-water interface. And so that becomes both a technical challenge and an operational challenge to figure out how to resolve that or how to best execute that.
We joke as submariners that the ocean is always out there ready to kill you or trying to kill you. The pressures that the vehicles operate at are harsh. It’s a harsh environment. It could be really cold, it could be really warm. You take metals and batteries and other electronics into salt water that you have to protect and make sure it is isolated there. So that adds additional technical complexity.
And then the last bit is in that void of communication and information, trying to manage that three dimensional domain, how you function there. It’s a little bit like if I was to blindfold you and have you walk around somewhere and go upstairs and downstairs. How does it function in that space where you have limited sensors, limited sensory information coming in that it must collect, analyze and make decisions on, so it becomes a really complex environment to operate in.
Geoff: Can you explain what you did to mitigate those navigational and those sensing challenges, and those communications challenges? Is Orca going to have any kind of novel technology involved, or is it just working with what is already out there?
Capt. Lewis: I would say since this started out … there was a sense of urgency to move on this. I would say that we did not go after novel technologies because we wanted-slash-needed mature technologies that could be incorporated into this. One of the things that makes it challenging for operating in the environment is incorporating all those sensors, all that information. And Orca does have some situational awareness ability, some sensors on it, to execute that.
And as we put all those pieces-slash-components together, another challenge that we have is you have to build out that industrial base. Some of it comes easier than others, some of it doesn’t. But I think across the board, just like you hear about the submarine industrial base or other supply chain challenges across the defense industry, or even the commercial industry, those all have an impact for a system like Orca, especially the scale of it, the size of it.
And one thing I’ll add about the industrial base is when I say that, I’m including the workforce, the quality of craftsmanship, workmanship that goes on, as well as the supply chain-slash-material challenges that have come to the forefront of everybody’s mind, especially during the COVID timeframe. So that has, I think, kind of infiltrated all aspects of industry, defense and otherwise.
Geoff: One last technical question. When Orca is deploying these CDMs, does something open on the bottom and the Orca will just drop them off?
Capt. Lewis: That’s a great question. I think the best way I can describe this is it’s gravity dropped. There’s no impulse. There’s no kinetic measure to shoot off or eject these payloads. Again, though, to just characterize operating in the undersea domain. Anything that you do, CDMs or not, [Orca] has to manage buoyancy. I haven’t mentioned that yet. So changes in salinity and temperature and depth all affect the buoyancy of a vehicle, and so it has to manage that in any payload that you drop.
In this case, CDMs, you have to be able to compensate for that in the buoyancy aspect, so that adds complexity to these things. But to your specific question, yeah, I would say it’s probably most akin to opening a door and having a payload drop out of it, slide out of it, fall out of it. Part of the payload system ingests water to manage the offset of the weight from the CDM for the buoyancy.
When you talk about [navigation], or talking about nav accuracy, in this case with CDM, that’s another element that makes this challenging, because a surface ship, or an aircraft have, I’ll say in a non-contested peacetime environment, they have GPS that they continually know where they’re at. And so in the undersea domain, you don’t have that GPS signal that you can follow along in your journey, in your mission.
And so as it executes its mission, it needs to be able to precisely drop a CDM or any other payload along the way. And so that’s, again, another complication. There’s ways to tackle that, but it becomes a challenging problem, depending on the actual task.
Geoff: Can you walk us through what’s coming up for Orca in this calendar year? What do you guys have planned?
Capt. Lewis: We anticipate taking delivery of what we call XLE-1. That’s the first vehicle the Navy will receive from Boeing. Once we receive the vehicle following their testing, the Navy will conduct developmental and operational tests, and expect that to go through the third quarter of [2025]. So as we do that, we are also incorporating [the Unmanned Undersea Vehicles Squadron 1 or UUVRON 1], so our sailors that will operate the vehicle, we’re incorporating them in the training and testing to make sure that we’re partnered up with the fleet, that they are ready to receive the vehicle and continue their operations and training as they take over the vehicle.
The second vehicle we expect to arrive to the Navy from Boeing in the summer of ‘25, and the follow-on vehicles, we’re still assessing the schedules. Again, this is somewhat driven in response to industrial base challenges that the team is working through.
Geoff: What is the ballpark cost of these Orcas, and as it currently stands, how many does the Navy want to field eventually?
Capt. Lewis: It’s on the order of $450 million. Boeing has been, I’ll say, a great partner in this … And I’ll say they are, from my perspective, equally committed as we are to get this capability out. With respect to the number of vehicles the Navy has or is interested in, right now, we have the five vehicles under contract, and that’s what I can say with that right now.
Geoff: How long can you program [Orca] to act autonomously? Do they have a certain amount of time a mission can take? That is, they would launch, do their thing, and then return within a certain time frame? Or is that pretty flexible in terms of how long they can go out once they kind of know where they need to go and where they need to come home to?
Capt. Lewis: The requirements are 30 days, and the capability is roughly 6,000 nautical miles. And I’ll go back to my previous comment about we have a lot of learning to do … Obviously we would not take the vehicle and immediately launch her from day one for a 30-day, 6,000 mile journey. So with any new thing that we have, we’re going to have our way to work up and baby steps learn along the way. I’m sure there’s things that we’ll learn operationally and functionally with the vehicles as we work our way towards those sorts of end states.
Geoff: Do you see the Orcas being — you mentioned they’d be under the [Unmanned Undersea Vehicles Squadron 1] — but would they be assigned to a given carrier strike group, depending on where they’re going, or certain ships or units? And then tied to this, can they operate cooperatively? Or can they operate in any kind of “hunter/killer” capacity with manned submarines? Or do you see that kind of cooperation coming down the line eventually?
Capt. Lewis: Start with the cooperation piece. I think in any unmanned space, especially when you mentioned hunter/killer, sort of in cooperation with a submarine, the disadvantage that any UUV has is speed. Speed through the water takes a tremendous amount of power and energy, and what really affects UUVs is they just don’t have that. The beauty of a [nuclear-powered submarine] is that nuclear power plant that gives us that unlimited, relatively speaking, propulsion, that we can go fast. UUVs, I think any time in the near future, anything reasonable, they will always be challenged by power. And so to get any vehicle to move at speed that could move with a battle ship or speed in comparison to an SSN or something like that, there’s tremendous hurdles to somehow find the ability to do that.
You mentioned in capacity or in coordination with other assets. Broaching or going across that air-water interface is an operational capability that Orca has. But that’s one of the challenges, if you send this vehicle, or any vehicle, if you submerge it, let it go for 20 days, if you don’t break that air-water interface, then you can’t have it. It’s much harder to get it to interact and change the course of its mission.
That’s another unique characteristic we talked about before, about operating in the undersea domain, is there’s an element there that it needs to break that interface to communicate to another vessel, an operations center, if it needs to be reprioritized, re-commanded to do some other sort of tasking.
Geoff: So basically you’re saying it needs to surface to get fresh orders, so to speak?
Capt. Lewis: Taking that interface could be done, sticking an antenna up. And there’s other ways across the Navy we’re looking at doing where we can minimize that. But right now, it’s still a challenge to do that sort of across the board.
Geoff: Are there ways to command it to surface at certain times so it can check for new orders coming over the air?
Capt. Lewis: So one of the unique characteristics with Orca is that it’s a diesel electric vehicle. And so in this case, the design of the vehicle does bring it up to the surface so it can have an induction mast that brings the air in for the diesel to operate and recharge the batteries. So I’ll say that Orca inherently has opportunities to do that, to be able to communicate and receive different tasking, should a commander want to do that.
Geoff: How fast does the big guy go at this point?
Capt. Lewis: Transit is good to estimate at three knots. So that’s the other thing. I remember when I was a young junior officer there was a video game, it was horrible to play, called [688(I) Hunter/Killer, a submarine simulation game], and you had to put it on eight-times speed. You could speed it up because that’s how slow submarine warfare is. So you would maneuver the submarine and then speed it up eight times to see what things look like 45 minutes later in the game.
Things go really slow underwater. And so if you’re going three knots, four knots and transiting, it takes you a long time to go somewhere. If you need to get out of somewhere, you don’t cover much ground either way. So that’s just another element of operating in the undersea domain.
Geoff: As the Navy envisions it, could an Orca be launched over the side of a large ship or a well deck, or would they be setting out from wherever and just going it alone?
Capt. Lewis: Right now, for Orca, it would be the latter. It goes out on its own, not deployed from a strike group or anything like that. Could things be done like that from another type of platform, or UUV? I don’t think that’s out of the realm of possible, but that’s not Orca, and there’s a lot of integration and other things that would have to happen … It would be out on their own, deployed from the pier type of concept.
Geoff: Circling back, you’re basically in Block I of Orca right now. Given the platform, is it something that you think will be able to take on additional capabilities in the future as the Navy gains experience with the platform and technology matures?
Capt. Lewis: Absolutely. I think it’s actually a really important platform for us to learn and operate and iterate off of. There’s a number of capabilities that I think I can conceive being incorporated into a platform like this. Talking about how challenging the environment is, I think Orca has tried to tackle some of those hardest problems for the Navy. And compared to some other vehicles and systems out there, it is addressing those challenges, and we’re going to learn a lot from it, doing things and operating in that three-dimensional space that some other vehicles are not operating in.
So there’s a ton of things that we need to integrate across, I’ll say the mission thread, of deployments, employment, what sort of command and control we envision, what sort of payloads could we employ from it. I think there’s tremendous opportunity to investigate that and explore that with Orca and as well as other UUVs.
My perception of doing work like this is, we’re at the initial stages … similar to aviation back in the early 20th century. We’re in that sort of realm of, what do we know? How do we know what we know? Know what we don’t know, known unknowns, you don’t know what you don’t know, all that. I think we’re at the early stages of figuring all that out. So, tremendous opportunity with Orca to go learn and expand what we can do and provide other new capabilities for the Navy.
Geoff: Is Orca the most advanced UUV that the Navy has developed? How does it compare to other UUV assets that are already operating in the fleet?
Capt. Lewis: I’ll hesitate, I think, on the most advanced, because I think my caution would be, how do I slice and dice that? I think it definitely is the most challenging problem that the Navy has attacked, with undersea unmanned vehicles.
Like I was saying, it is a really hard problem to manage operating in that three dimensional space from shallow water to deeper water with contacts around you, to the air-water interface, let alone being able to do all the other parts of command and control, autonomy, sensing, payload, deployment, etc. So it is a very complex problem that the Orca program went after to go challenge. So yeah, in that sense, I think it is. It is probably the biggest or most complex one there. I don’t know if I’d say the most advanced, because I’m not sure how I’d slice and dice that. But it is a significant challenge, operational capabilities that the Navy has tackled.
Geoff: You’ve been in the chair over there for a while now. What’s your personal favorite part about Orca, or the coolest detail that you’d want people to know about? Anything you’ve enjoyed learning about the platform and what it can potentially do?
Capt. Lewis: I think when you see the size of it. So when you say it’s like a school bus or a semi, I think that is impressive, and when you see pictures of it, you need something that you can get a sense of the scope, the size of it, the perspective of it.
It feels unjust calling it a UUV because it’s so big. I sort of think of UUVs as something maybe two sailors can grab and throw over the side into the water, or something like that. So the scope or the size, the magnitude of it, is impressive.
I can appreciate the challenges of trying to operate across the undersea domain from shallow to deep, to do the mission set that’s extremely challenging, to take all that in, all that information, all that decision making, and try and tear down 150 smart sailors and a highly technical machine in an environment that is looking to kill you. Boil that down into an unmanned system. It’s pretty impressive.
Geoff: It sounds like you’re pretty hopeful that Orca will help guide the Navy’s future UUV efforts as well, when it comes to communication and range and stuff like that.
Capt. Lewis: I was really excited to see the CNO’s NAV Plan that she just released, with Project 33, and one of those pillars being robotic and autonomous systems, and her drive to pursue and execute the hybrid fleet. I think that just shows the importance of unmanned systems and incorporating them into what we do. As I heard the CNO say, going after the dull, dirty and dangerous items. And I think Orca and other unmanned systems really get after that, and let our sailors and our also our more precious investments, like submarines or surface ships, be able to do other tasks for the Navy.
Geoff: Where are you guys going to be doing the operational testing and evaluation this year?
Capt. Lewis: That will be happening out in Southern California, Port Hueneme, that’s where the UUVRON detachment is.
Geoff: Anything else you’d like to add or share about the Orca?
Capt. Lewis: I guess what I would close or leave with is, going back to the CNO’s drive to bring unmanned systems into the fleet. I think it’s a really exciting time to be in our program office and in the Navy working on these sorts of challenges. There is a lot to learn. I think we’re in this spot where we need to bring capability to the fleet, and then we need to be able to learn and iterate off of that, because we don’t have enough of these things operating at scale to facilitate that learning, I think, at the scale we need.
I know I’m biased in the undersea domain. It’s an extremely hard problem to do all this. The thing that you mentioned at the early part of this conversation, you know, if it’s deploying other kinetic effects, or other systems like UAVs, or transporting some sort of logistics, maybe in support of SEALs, not necessarily the SEALs themselves. We started looking at all of that.
This really becomes a system of systems discussion, because on a submarine, they’ll tell you, we operate out there, alone and unafraid. And we really do do that. But when you start looking in the UUV space, I think we need to open the aperture and we have to look at the system of systems to go execute some of these potential missions, or investigate those mission areas.
Unfortunately, some of the world events have shown us the necessity, or some glimpse of the future, of being able to iterate and operate some less expensive systems that don’t bring humans into harm’s way. So I think we, as the Navy and the DOD, will continue to explore that path.
Email the author: geoff@twz.com
