United Launch Alliance's Vulcan rocket, under contract for dozens of flights for the US military and Amazon's Kuiper broadband network, lifted off from Florida on its second test flight Friday, suffered an anomaly with one of its strap-on boosters, and still achieved a successful mission, the company said in a statement.

A shower of sparks was seen flying from near the Vulcan's engines about 38 seconds after Friday's liftoff from Cape Canaveral Space Force Station.

The rocket company, jointly owned by Boeing and Lockheed Martin, has been racing to prepare its vehicle to carry military satellites.