New Umbilical Fitted for Mobile Launcher to Support NASA’s Deep Space Exploration Missions

A fit check of the core stage inter-tank umbilical is in progress on the mobile launcher tower at Kennedy Space Center in Florida
High up on the mobile launcher tower at NASA’s Kennedy Space Center in Florida, construction workers assist as a crane moves the Core Stage Inter-tank Umbilical into place for a fit check of the attachment hardware. Photo credit: NASA/Glenn Benson

Engineers lifted and installed a third umbilical on the mobile launcher at NASA’s Kennedy Space Center in Florida for a fit check. The tower on the mobile launcher will be equipped with several connections or launch umbilicals like this one. After the fit check was completed, the umbilical was lowered down and will be installed permanently at a later date.

The umbilicals will provide power, communications, coolant and fuel. They will be used to connect the mobile launcher to the agency’s Space Launch System (made up of the core stage, twin solid rocket boosters, and the interim cryogenic propulsion stage) and the Orion spacecraft mounted on top of SLS.

An area on the SLS between the liquid hydrogen and liquid oxygen tanks is known as the core stage inter-tank. The core-stage inter-tank umbilical is the third in a series of five new umbilicals for the mobile launcher. Its main function is to vent excess gaseous hydrogen from the rocket’s core stage. This umbilical also will provide conditioned air, pressurized gases, and power and data connection to the core stage.

The Orion service module umbilical and the core stage forward skirt umbilical were previously installed on the tower. The service module umbilical will connect from the mobile launch tower to the Orion service module. Prior to launch, the umbilical will transfer liquid coolant for the electronics and purge air/gaseous nitrogen for environmental control. The SLS core stage forward skirt is near the top of the core stage, and the forward skirt umbilical provides connections and conditioned air/gaseous nitrogen to the core stage of the rocket. All these umbilicals will swing away from the rocket and spacecraft just before launch.

Several other umbilicals were previously installed on the mobile launcher. These include two aft skirt purge umbilicals, which will connect to the SLS rocket at the bottom outer edge of each booster and provide electrical power and data connections, remove hazardous gases, and maintain the right temperature range with a nitrogen purge in the boosters until SLS lifts off from the launch pad.

The Ground Systems Development and Operations Program at Kennedy is preparing ground support equipment, including the launch umbilicals, for NASA’s deep space exploration missions.

Liquid Oxygen Tanking Operations Begin at Launch Pad 39B

Praxair trucks offload liquid oxygen into a giant storage tank at Launch Pad 39B at Kennedy Space Center in Florida.
Several Praxair trucks carrying their loads of liquid oxygen, or LO2, arrived at Launch Pad 39B at NASA’s Kennedy Space Center in Florida. A mist is visible as LO2 is offloaded from one of the trucks into the giant storage sphere located at the northwest corner of the pad. Photo credit: NASA/Kim Shiflett

The first major integrated operation at Launch Pad 39B at NASA’s Kennedy Space Center in Florida began with the initial tanking of a cryogenic fuel into a giant sphere at the northwest corner of the pad. The tanking operation is one of the steps needed to bring the center closer to supporting the launch of the agency’s Orion spacecraft atop the Space Launch System rocket on its first uncrewed test flight.

“When I think of launch operations, there are distinct pictures that come to mind,” said NASA Launch Director Charlie Blackwell-Thompson. “One of them is during the tanking operations as the cryogenic propellants are loaded into the Space Launch System rocket.”

Several Praxair trucks arrived at the center and offloaded their liquid oxygen, or LO2, slowly, one at a time, into the cryogenic sphere to gradually chill it down from normal temperature to about negative 298 degrees Fahrenheit. Praxair, of Danbury, Connecticut, is the company that provides the agency with liquid oxygen and liquid hydrogen.

Another wave of trucks arrived and offloaded their LO2 all at the same time. During the next several months, trucks will continue to arrive from Praxair and offload about 40,000 gallons of fuel two days per week into the sphere that can hold about 900,000 gallons of liquid oxygen.

The procedure to fill the liquid hydrogen storage sphere will begin in November and will be completed in the same way. When both tanks are filled to about halfway, engineers in a firing room in the Launch Control Center will perform pressurization tests. Additional tests will be performed with the mobile launcher around mid-2018. The cryogenic fuels will remain in the tanks.

Blackwell-Thompson said it is not uncommon during tanking to see vapors and mist in the cryo storage area and near the vehicle. This week, she got a preview, when the trucks offloaded the first round of LO2 and once again, cryo vapors were visible. Because some of the liquid oxygen boils off during tanking, additional LO2 is required.

“This is a very important step in our path to launch, and we are thrilled to have cryo propellant return to the pad,” Blackwell-Thompson said.

The Ground Systems Development and Operations Program is preparing the pad for the launch of Exploration Mission-1, deep space missions and the Journey to Mars. Significant upgrades to the pad include a new flame trench beneath the pad and a new flame deflector.