Future US Coast Guard’s Heritage class cutter Argus (Picture source: Eastern Shipbuilding Group)
According to a tweet published by Eastern Shipbuilding Group on July 12, 2022, the company successfully transferred Offshore Patrol Cutter (Heritage class cutter) Argus Hull 1 to launch position and shifted Hull 2 for the next phase of production at Berard Transportation.
This is a routine report of progress, though it has been a long time coming, but one thing caught my eye,
“She is able to reach a top speed of 24.5 knots (45.4 km/h)…”
I had been disappointed when the request for proposal specs identified 22 knots as the acceptable threshold for speed. 25 knots was identified as the goal and I always felt it should have been the threshold. Even a couple of knots makes a big difference in their potential use as escort vessels. What we have seen repeatedly is 22.5 knots from official sources. Official sources do tend to be very conservative. Looking at the combination of length, displacement, horsepower, it has always seemed to me, they should make 24 to 25 knots max, at least in most circumstances. (Some WWI light cruisers were closely analogous.) The Wikipedia entry for the Heritage class cutters has reported a maximum speed of 24.5 for some time. Hopefully the Navy Recognition report is based on an Eastern Shipbuilding news release and represents their best estimate of maximum speed. I am hoping we get some reports of actual maximum speed from the sea trials.
Chuck Hill's CG Blog 
Damn. Aircraft carriers top out at 30 + kts.
24.5 is SLOW. Even the 50 year old 378’s were 29+
It is counter intuitive but in many ways the large a ship is the easier it is to make it go fast. At the very least as the ship gets bigger you need to devote a smaller percentage of its mass to providing power for any given speed.
The new Constellation class frigates only do about 26/27 knots.
Even 22.5 is three knots faster than the Bear class and 4.5 knots faster than the 210s.
We seldom used the gas turbines on the Hamilton class 378s. On diesels we could do at most 19. Using one turbine we could do 22 or so. The average speed the OPCs make operationally is probably going to be higher than it was for the 378s and considerably higher than the current fleet of WMECs.
Typically on a displacement hull, to add four knots you have to double horsepower and fuel consumption.
Was that increased speed on the 210’s due to the newer engines? The Confidence on a really good day could get to 16 knots at flank speed with some help from the engineers. The turbines gave us six knots when we did run them. They were separate from the mains and only ran just to keep them viable.
@Peter, as you probably know, only the first five 210s were built with the CODAG arrangement, two 1500 HP diesels and two 1000 HP gas turbines. Max speed required all four engines on the line. The other eleven 210s had two 2500 HP diesels. The mid-life rebuilds did not increase the engine power, still only 5,000 total.
Okay. We never ran the main diesels and turbines together. The SOP seemed to be to fire up the turbines for a few hours each patrol and that was it.
I bet they grabbed that 24.5 from the Vard web site and didn’t check that the web site version uses the 10MW 20V engines.
The OPCs have almost the same HP as the propulsion diesels installed on the National Security Cutters, so they should be able to make about the same speed as the NSCs on diesels alone. I think I recall hearing that the NSCs could make 24 knots on diesels alone.
Got this from Eastern Shipbuilding. This is the third OPC.
MEDIA ADVISORY
Wednesday, July 13, 2022
Eastern Shipbuilding Group to Host Keel Laying Observance for U.S. Coast Guard Cutter Ingham
Friday, July 15, 2022
What: Keel Laying Observance for USCG Cutter Ingham
Who: Joey D’Isernia, President, Eastern Shipbuilding Group, Inc.
Rear Admiral Chad L. Jacoby, Director of Acquisition Programs & Program Executive Officer (CG-93), U.S. Coast Guard
Congressman Neal Dunn (FL – 2nd District)
Where: Eastern Shipbuilding Nelson Street Facility
2200 Nelson Street, Panama City, FL
When: Friday, July 15, 2022 – 10:00 AM CDT Set Up / 10:30 AM CDT Event
On Friday, July 15, Eastern Shipbuilding Group will host the keel laying observance for the U.S. Coast Guard’s Offshore Patrol Cutter (OPC) INGHAM (WMSM-917). The presiding official for the U.S. Coast Guard will be Rear Admiral Chad L. Jacoby, Director of Acquisition Programs & Program Executive Officer (CG-93). Congressman Neal Dunn (FL – 2nd District) will be the senior official in attendance.
Request Media Credentials:
Please email Jessica Ditto at jditto@easternshipbuilding.com by 6:00 PM CDT,
Thursday, July 14, 2022 to request media credentials.