The Atlantic Corp. shipyard was established in 1918, on the site of a failed paper factory in the area of the Piscataqua River Bridge, and folded in 1920. The company also built a housing estate for its workers, adjacent to the shipyard. The shipyard site is now occupied by an Irving Oil heating oil terminal, a U.S. Goldbond gypsum board plant and White Mountain Lumber Company. See the site of the shipyard from the air on Google here. In Google's maximum magnification, you can just see the shadow of the old launch ways under the water, in line with the axis of the gypsum plant, which must have been built on the foundations used by the shipyard's fabrication shop. The lumber company's building with the black roof is believed to be the only one on the site that dates back to the shipyard. The housing estate is just to the northwest, now separated from the shipyard by I-95.
| Hull # | USSB # | Name | Owner | Type | GT | Delivery | Disposition |
| 1 | 987 | Kisnop | US Shipping Board | Cargo Ship | 5,500 | Aug-19 | To Britain 1941 as Empire Dabchick, torpedoed and lost 1942 |
| 2 | 988 | Babboosic | US Shipping Board | Cargo Ship | 5,500 | Sep-19 | Scrapped 1933 |
| 3 | 989 | Portsmouth | US Shipping Board | Cargo Ship | 5,500 | Oct-19 | Scrapped 1931 |
| 4 | 990 | Nipmuc | US Shipping Board | Cargo Ship | 5,500 | Dec-19 | Scrapped 1936 |
| 5 | 991 | Norumbega | US Shipping Board | Cargo Ship | 5,500 | Feb-20 | Scrapped 1931 |
| 6 | 992 | Brookline | US Shipping Board | Cargo Ship | 5,500 | May-20 | Later O'Brien Brothers 1931, Valiente 1940, Guatemala 1941, torpedoed and lost 1942 |
| 7 | 993 | Springfield | US Shipping Board | Cargo Ship | 5,500 | Jun-20 | Scrapped 1936 |
| 8 | 994 | Tolosa | US Shipping Board | Cargo Ship | 5,500 | Sep-20 | To Britain 1940 as Empire Dorado, in collision and lost 1941 |
| 9 | 995 | Pachet | US Shipping Board | Cargo Ship | 5,500 | Nov-20 | Scrapped 1932 |
| 10 | 996 | Pagasset | US Shipping Board | Cargo Ship | 5,500 | Dec-20 | Later Colabee 1937, torpedoed 1942 off Cuba but repaired, later Betsy Olson 1950, Chukoh Maru 1953, scrapped 1960 |
The L. H. Shattuck shipyard was also established in 1918, on a 110-acre site in the Newington section of Portsmouth, and folded in 1919. The shipyard site was redeveloped by Atlantic Dyestuff Company, which failed in the Depression, and since then the site has been used by a heating oil terminal. The remains of the uncompleted hulls can still be seen at low tide. See the site from the air on Google here.
| Hull # | USSB # | Original Name | Original Owner | Type | Tons | USSB Design | Delivery | Disposition |
| 1 | 391 | Chibiabos | US Shipping Board | Wooden Hull | 391 | 1001 | 1919 | |
| 2 | 392 | Haverhill | US Shipping Board | Wooden Hull | 392 | 1001 | 1919 | |
| 3 | 393 | Newton | US Shipping Board | Wooden Hull | 393 | 1113 | 1919 | Later SP 4306 NOTS – USAT/IX 33 |
| 4 | 394 | Woyaca | US Shipping Board | Wooden Hull | 394 | 1001 | 1919 | |
| 5 | 395 | Yawah | US Shipping Board | Wooden Hull | 395 | 1001 | 1919 | |
| 6 | 396 | US Shipping Board | Wooden Hull | 396 | 1113 | Not completed | ||
| 7 | 397 | US Shipping Board | Wooden Hull | 397 | 1001 | Not completed | ||
| 8 | 398 | US Shipping Board | Wooden Hull | 398 | 1001 | Not completed | ||
| 9 | 399 | US Shipping Board | Wooden Hull | 399 | 1001 | Not completed | ||
| 10 | 400 | US Shipping Board | Wooden Hull | 400 | 1001 | Not completed | ||
| 11 | 401 | US Shipping Board | Wooden Hull | 401 | 1001 | Not completed | ||
| 12 | 402 | US Shipping Board | Wooden Hull | 402 | 1001 | Not completed | ||
| 13 | 403 | US Shipping Board | Wooden Hull | 403 | 1001 | Not completed | ||
| 14 | 404 | US Shipping Board | Wooden Hull | 404 | 1001 | Not completed | ||
| 15 | 405 | US Shipping Board | Wooden Hull | 405 | 1001 | Not completed | ||
| 16 | 406 | US Shipping Board | Wooden Hull | 406 | 1001 | Cancelled | ||
| 17 | 407 | US Shipping Board | Wooden Hull | 407 | 1001 | Cancelled | ||
| 18 | 408 | US Shipping Board | Wooden Hull | 408 | 1001 | Cancelled |