WASHINGTON (Reuters) -New orders for U.S.-manufactured goods surged in March, boosted by demand for commercial aircraft, but the momentum was expected to fizzle amid trade tensions.

Factory orders increased 4.3% after a downwardly revised 0.5% rise in February, the Commerce Department's Census Bureau said on Friday. Economists polled by Reuters had forecast factory orders would surge 4.5% after a previously reported 0.6% gain in February.

Factory orders advanced 3.0% on a year-on-year basis in March. President Donald Trump's protectionist trade policy is hurting manufacturing, which accounts for 10.2% of the economy.

An Institute for Supply Management survey on Thursday showed its measure of manufacturing activity contracted for a second straight month in April. Tariffs were cited as problematic in every industry, with some of those surveyed taking issue with the disorderly manner in which the import duties were being imposed. 

Commercial aircraft orders soared 139.0% in March, but the gain is unlikely to be sustained. China has ordered its airlines not to take further deliveries of Boeing planes during its trade war with the U.S. Ryanair, Europe's largest low-cost carrier, on Thursday threatened to cancel orders for hundreds of Boeing aircraft if the tariff war leads to materially higher prices. 

Orders for motor vehicles, parts and trailers rose 0.6% in March. Transportation equipment orders vaulted 27.1%. But orders for computers and electronic products dropped 1.3%, while those for electrical equipment, appliances and components fell 1.0%.

Machinery orders edged up 0.1%. 

The government also reported that orders for non-defense capital goods excluding aircraft, which are seen as a measure of business spending plans on equipment, gained 0.1% in March, as estimated last month. 

Shipments of core capital rose 0.2%, revised down from the previously reported 0.3% increase. Business spending on equipment rebounded sharply in the first quarter.