How important is having AMDR on board to the future of the Flight III Burkes?

Flight III and AMDR are inextricably linked. If you have SPY-1 on the ship, it’s not going to be a Flight III; we would be building another Flight IIA. There’s no way I would go to the expense of changing the ship to accommodate the AMDR, and then put a SPY-1 radar on it.

Flight III and AMDR are inextricably linked. If you have SPY-1 on the ship, it’s not going to be a Flight III; we would be building another Flight IIA. There’s no way I would go to the expense of changing the ship to accommodate the AMDR, and then put a SPY-1 radar on it.

But I think I should talk about what I have to do to a DDG Flight IIA to take an AMDR radar. For starters, in order to service the AMDR, compared to SPY-1, the AMDR takes significantly more power and a fair amount more cooling capacity.

 

I’ve seen a briefing slide that shows you’re going for roughly a 50 percent increase in cooling capacity over the Flight IIA Burkes?

Correct. And, that’s just by the incorporation of new technology.

 

And, then to drive those A/C compressors you are increasing the size of your electrical power plant?

That is a fact, and here’s what drives it. The generators aren’t the issue, and I’ll give you a little more engineering to explain. Going from the existing 3-megawatt generator to 4-megawatt generators, the 4-megawatt generator isn’t that much bigger than a 3-megawatt generator, which is what I’ve got on a Flight IIA today. The 4-megawatt turbine generators on board DDG 1000 are almost identical to what we’re putting on the Flight IIIs, and there isn’t that big a difference size-wise. They’re made by the same company, and about 80 percent of the parts are the same. So it’s not that big a deal for me to say, “Hey, I want the 4-megawatt machine.”

What is a big deal is the rated voltage of the power, and that gets into the product of your current, which is how much electricity is flowing, the number of electrons that are flowing or shaking, times the voltage, which is how much energy each of those electrons is packing. For a given constant power, if I run that power at a higher voltage I get a lower current. Or, if I run it at a lower voltage I get a higher current. Again, we get back into the sweet spot of not too high, not too low. Low voltage has a lot of advantages. The biggest one is that the components are cheap, easy to work with, and hard to break. So I like low voltage, which is why we’ve used it for many years on the DDG 51s. The problem with that is that at a certain amount of power with that low voltage, your current gets so big that in an electrical fire you run the risk of melting your circuit breakers. These are designed to shut things off so that they don’t damage themselves in an electric fire. Circuit breakers are rated to be able to withstand a certain amount of current, and if you start having more and more power at a low voltage, you get such high current that even the best circuit breakers available won’t adequately protect you safely. So, you have to get that current down. How do you get the current down? You go to a higher voltage standard.

So, the bigger the change when I add the power, I have [to] go to the next standard higher, which is 4160, what DDG 1000 uses. It’s the current standard, and it’s the voltage standard on USS America (LHA 6). So I have to go to that higher voltage standard in order to safely manage the current on my ships. What’s the drawback there? The drawback is that that the switchgear for that voltage is more expensive, is heavier, and takes up more room. So, that gives me my design challenges in Flight III, though it’s not like the Navy doesn’t understand what 4160 is. It drives me in cost and some of the other areas where I’m trying to keep things lighter and less expensive, and that’s a trade that I’ve had to make in order to provide enough power to run the AMDR radar.

 

As currently projected, does the Flight III Burke design have adequate power to run all the projected versions of AMDR and the shipboard system simultaneously?

Yes. With two 4-megawatt generators running in parallel, Flight III will make 7.6 megawatts of useable power. That’s because when you run two generators in parallel, you don’t get all 4 megawatts out of each generator. Paralleling them, you lose some of the rated load through the distribution systems. So, a current Flight IIA DDG 51 takes about 4 megawatts to power everything aboard. We actually went to sea on Spruance (DDG 111) as she was being tested on builder trials, and literally turned on everything on the ship. Every heater, every shower head running a hot shower, the sonar at maximum power, the radar at high power, every light that we could flick on, every oven and stove … everything. We got to a full load of about 4 megawatts, give or take a bit. What we’re adding with Flight III is about another megawatt-and-a-half worth of equipment. So, that takes you to 5-1/2 megawatts of load, and the Flight III generators are going to be making 7.5 to 7.6. That’s about 2 megawatts worth of additional load I can put on over the course of the service life and still be able to turn everything on at once. That margin is similar to what we have on the Flight IIAs today. You’ll have about 2 megawatts worth of growth on the Flight III.

 

And, that should accommodate the projected AMDR X-band phased array radar if and when it comes along, correct?

Well AMDR-X will eat into that margin, so the question then is, are yesterday’s margins the right margins for the ships of the future? We’ve always said that a 40-year ship should go in with about a 25 percent to 30 percent margin of extra service life power, and that’ll get it through 40 years. And from World War II to today, that’s been right. Now, you get to ask, “Am I going to have a directed energy weapon or rail gun in the future?” Is that amount of power margin the right power margin for the future?” I think the Navy is in the middle of a conversation as it talks about the ships beyond Flight III, and that our current assumption’s still valid. That’s a different conversation, and was never my tasking on Flight III. My tasking in developing a Flight III was to install an AMDR on the Flight IIA platform, and maintain the kind of margins and performance that we’ve seen on earlier Burkes. And that’s what I can do with a Flight III. The question of what should our fleet look like in the future is a fine question. It’s a different question than that, and I think it’s a question that you’re going to see OPNAV [Office of the Chief of Naval Operations] talking more and more about. I know it weighs heavily on [Rear] Adm. [Thomas] Rowden’s mind, and I know he’s got a lot of people putting a lot of effort in it, and I think he’ll start talking about that when he’s ready to. But that’s the kind of question that’s the next question after this.