The Japanese H-IIA and H-IIB utilize MLPs when launching from the Yoshinobu Launch Complex. Between 2009 and 2010, another MLP was constructed as part of the Constellation program, known as Mobile Launcher-1 (ML-1). Since the cancellation of the program in 2010, ML-1 was converted for the Space Launch System Block 1, with various phases of construction between 2013 and 2018. The biggest modification to the ML-1 was on the platform's base, where engineers increased the size of a exhaust duct to a rectangle stretching and strengthened the surrounding structure. The SLS will weigh more than twice as much as the planned Ares I rocket. The Ares I rocket would have featured a single solid-fueled first stage, while the SLS will include two large solid rocket boosters and a powerful core with four RS-25 engines. The base of the ML-1 is high, long, and wide. The ML-1 also features a Launch Umbilical Tower (LUT) with several arms that will permit servicing of the SLS on the launch pad, and will swing away from it at launch. On June 2019, NASA awarded a contract for the design and construction of Mobile Launcher-2 (ML-2) for SLS Block 1B. United Launch Alliance's Vulcan will use an MLP similar in design to the one used by the Atlas V when launching from SLC-41, altered to support the former's larger design. The Vulcan MLP stands tall, and when complete will weigh . It will be equipped with various electronics, power-lines, and cables to support and control the rocket. For the initial Vulcan-Centaur configuration, the MLP will supply liquefied natural gas and liquid oxygen to the first stage, and liquid hydrogen and liquid oxygen to the Centaur upper stage. the basic structure has been completed, but the umbilicals and equipment have yet to be installed. The Mobile Launcher Platform-3 (MLP-3) was acquired by Orbital ATK (who was later bought out by Northrop Grumman) to launch their future OmegA rocket with. They will use the Vehicle Assembly Building High Bay 2 to assemble the rocket, and crawler-transporter 1 to move the rocket to LC-39B for launch. Once delivered to the pad, the mobile launch platform is connected to the larger sound suppression system by large pipes which deliver a deluge of water from an adjacent water tower. Six towers known as "rainbirds" spray water over the MLP and into the flame deflector trenches below it, absorbing acoustic waves.