New cockpits will bring the Shuttle into the space age
Tim Furniss/LONDON
Milliseconds can make a big difference during a Space Shuttle launch. The faster the crew can react to a problem, the greater possibility of avoiding disaster. That is where "glass cockpits" - cockpits with digital displays - come in.
NASA recently unveiled a new Boeing 777-style glass cockpit, which it has installed in the Space Shuttle Atlantis (above). The United Space Alliance, the Boeing-Lockheed Martin company that operates the fleet, claims it should "make today's Shuttle safer, more capable and less expensive to fly".
This orbiter will be the first to fly with the new multifunction display subsystem (MEDS), developed by Honeywell Space Systems of Phoenix, Arizona, for about $200 million. Installing the systems in the Atlantis and the Columbia, Discovery and Endeavour, will cost $9 million each.
"It helps the crew analyse and react quicker," says United Space's Andy Allen, a three-time Shuttle veteran. Allen should know. On his final mission, a false reading on a Shuttle display nearly forced his crew to abort the mission as the vehicle lifted off. A more comprehensive display such as the MEDS could have prevented the moments of anxiety.
NASA's cockpits have lagged behind those available to less futuristic craft. For example, newer NASA pilot astronaut recruits, used to flying jets with glass cockpits, had to train for groundbreaking space missions with less modern displays.
But that will change with the MEDS, which displays more information more quickly, is lighter and uses less power than the original design. All these factors give crews the convenience and control of the most advanced commercial and military flat-panel display technology.
Although the upgrades enhance crews' capabilities, the familiar positioning of the layout locations is little changed. Engineers have gutted Atlantis' cockpit and replaced outdated electromechanical displays with11 full-colour, flat-panel ones. The system gives Shuttle crews easy access to vital information through the two- and three-dimensional colour graphic and video capabilities of its onboard information management system. Information will be interchangeable between screens, allowing crews to select the best display format for their mission.
Not only does the new system improve crew/orbiter interaction with the easy-to-read graphic portrayals of key flight indicators like altitude display and Mach speed, it reduces the high cost of maintaining obsolete systems.
Flightdeck displays
Atlantis' forward flightdeck is equipped with nine MEDS displays, while two MEDS units were installed in the aft flightdeck to support payload operations. Each display unit measures about 200mm (8in) square, weighs 8kg (18lb) and uses 67W of power. The screen has a resolution of 172dpi.
The MEDS hardware consists of 11 identical full-colour liquid crystal multifunction display units (MDUs). Four directly replace the four monochrome units of the old system. Two MDUs each replace the commander (CDR) and pilot (PLT) flight instruments; one MDU supplants the on-orbit manoeuvring instruments at the aft flightdeck; and the remaining two MDUs replace the CDR and PLT status displays. A four-string fault-tolerant architecture drives these displays under the control of four integrated display processors.
Four analogue-to-digital converters and 16 databus couplers complete the MEDS. The command and data entry keyboards, the rotational and translational hand controllers and most cockpit switches, are unchanged.
The change to the MEDS is also necessary because electromechanical devices are becoming obsolete and increasingly expensive to maintain. Besides reducing maintenance costs, the MEDS will reduce vehicle weight and power consumption, improve Shuttle reliability and performance and enhance Shuttle safety by simplifying cockpit panels and providing a redundant display capability.
The MEDS can be upgraded to expand vehicle and payload management, simplify crew training, reduce orbiter turnaround time, eliminate obsolete hardware and provide modular building blocks to help NASA reach its goal of commonality among the avionics systems of the Shuttle, the International Space Station (ISS) and future initiatives.
The Atlantis will make STS101 the first glass cockpit, or MEDS, mission, under the command of US Air Force Col Jim Halsell, on the third flight to the ISS. This will take place once the delayed Russian Service Module reaches orbit - possibly in December.
Source: Flight International
