WASHINGTON (Reuters) - Democrats in the U.S. Congress are to release a sweeping plan on Monday to provide more than $50 billion in additional assistance to U.S. airlines, transit systems, airports and passenger railroad Amtrak and create a $3 billion program to assist aviation manufacturers with payroll costs, according to documents seen by Reuters and sources briefed on the matter. The $1.9 trillion COVID-19 relief proposal will provide $30 billion to transit agencies, $14 billion for passenger airlines, $8 billion to U.S. airports, $1 billion for airline contractors and $1.5 billion to Amtrak, the draft legislation says. U.S. House committees are set to vote on the legislation on Wednesday. Airline stocks rose sharply on news of the new funding, with American Airlines up 4.2%, while United Airlines gained 5% and Southwest Airlines jumped nearly 6%. President Joe Biden had proposed $20 billion for struggling U.S. transit agencies - and nothing for airlines - while Democrats had pushed for more transit help, citing the collapse in travel demand as a result of the COVID-19 pandemic. Transit agencies have previously been awarded $39 billion in emergency assistance by Congress. New York’s Metropolitan Transit Agency says daily subway travel has recently been down 70% or more. U.S. airlines have been awarded $40 billion in payroll support since March and airline unions had asked Congress for another $15 billion to keep thousands of workers on the payroll past March 31, when the current round of funding expires. The additional $14 billion will keeping nearly 30,000 airline workers on the job through Sept. 30. A summary of the $14 billion airline payroll proposal from the House Financial Services Committee seen by Reuters noted airlines lost over $35 billion in 2020 and “airlines do not expect to return to profitability until midway through 2021. The $3 billion aviation manufacturing program would provide a 50% government subsidy to cover costs of pay, benefits and training for employees at risk of being furloughed or who were furloughed due to the pandemic. The grants cover up to 25% of a company’s U.S. workforce. U.S. airplane manufacturer Boeing and suppliers have cut thousands of manufacturing jobs over the last year as demand for new planes has shrunk amid the collapse in airline travel. Boeing said last year it recorded severance costs for 26,000 employees in 2020, with 18,000 having left last year and the remainder expected leave in 2021. Boeing did not immediately comment on the program. International Association of Machinists and Aerospace Workers (IAM) President Robert Martinez urged lawmakers to back the effort to provide payroll assistance to “help this critical workforce and supply chain weather the storm of this historic pandemic.”