U.S. Rep. Joe Courtney, D-2nd District, is drumming up support for a proposal, included in President Donald Trump's budget, to bolster attack submarine production.

Courtney has spearheaded a request to the two U.S. House lawmakers in charge of the subcommittee with oversight of defense appropriations, asking that money be included in the defense budget to support the buildup. More than 70 of Courtney's colleagues have signed on to the letter, which was sent Monday to Reps. Peter Visclosky, D-Indiana, and Ken Calvert, R-California.

"The Virginia-class submarine remains one of the most effective and sought after tools in our nation's arsenal," the letter says.

The U.S. submarine fleet is on track to dip to 42 boats in the late 2020s unless there's additional investment. That's because the Navy is retiring the older attack submarines at a faster rate than the newer, Virginia-class attack submarines are being built. The Navy has said it needs 66 attack submarines to carry out its missions, compared to the 52 it has now.

The Navy is requesting money for a third attack submarine to be bought in fiscal year 2020 to help mitigate the dip. For the past several years, the rate has been two a year. The Trump administration opposed the third-sub proposal, pushed for by Courtney, when it came up in Congress last year but since has decided to back it.

Russia has continued to build more advanced submarines and China is on track to reach about 70 submarines by 2020, placing the U.S. submarine force at the "forefront of great power competition and our combatant commanders will need more submarines, not fewer, in the coming decades," the letter from the lawmakers says.

The lawmakers are asking for about $10 billion in funding for the Virginia-class attack submarine program in the next budget. In recent years, Congress has appropriated about $7 billion for the program.

The boost would have a positive impact on the defense industrial base, a job producer for congressional districts. Courtney's 2nd Congressional District includes submarine builder Electric Boat, which has hundreds of suppliers in Connecticut.

EB's shipyard is expected to experience a drop in its workload between construction on the first and the second boat in a new class of ballistic missile submarines, which will carry about 70 percent of the U.S.'s deployed nuclear arsenal. Construction on the first of these submarines is expected to start in fiscal year 2020, and the second is expected to start in fiscal year 2024. The third attack submarine in 2020 would help mitigate the dip, the letter says.

The letter also urges continued support for the ballistic submarine program, requesting about $2.4 billion for that program in the next defense budget. Congress has approved aggressive construction plans by the Navy for the program, which is a top priority of Navy and Pentagon officials. The lawmakers also are requesting additional funding for supplier development to ensure they are prepared to meet the schedule.

j.bergman@theday.com