“This is Atlas Mission Control at T-minus ten, nine, eight…”
On 18 June, United Launch Alliance (ULA) will conduct the 50th flight of its Evolved Expendable Launch Vehicle (EELV), marking a significant milestone in an effort that began in the early 1990s as an Air Force initiative to develop a more reliable and affordable means of placing government payloads into orbit. When ULA’s venerable Atlas V booster blasts off from Pad 41 at Cape Canaveral Air Force Station, it will deliver a classified satellite for the National Reconnaissance Office and continue a proud record of achievement for a vehicle whose heritage stretches back over five decades.
“…seven, six, five…”
Right from the outset, the EELV was in the hands of the Air Force, its primary proponent, developer and sponsor. The original idea was that it would provide an improved launch architecture, offering standardised payload fairings, common booster cores and upper stages and optional strap-on boosters. Over the course of its operational lifetime, it was anticipated that the EELV will achieve cost savings as high as 25 percent over earlier designs. Bids to develop it came from Lockheed Martin, Boeing, McDonnell Douglas and Alliant Techsystems and a series of $30 million first-phase contracts were awarded in late 1996. At first, Boeing considered using a modified Space Shuttle main engine in its design, but after acquiring McDonnell Douglas in 1997 it adopted the latter’s Delta IV as the core of its proposal. Lockheed Martin, meanwhile, based its architecture on the Atlas V.
“…four, three, two…”
At length, Boeing and Lockheed Martin won the final phase of the bid. Both devised common booster cores, whose philosophies emphasised standardisation and the use of proven, reliable technologies, and in October 1998 development and initial launch contracts, totalling more than $3 billion, were awarded. Several years later, the discovery that Boeing held in its possession documents from Lockheed Martin sparked claims of industrial espionage, and, to end litigation, the companies merged their efforts and formed ULA in December 2006. For its part, the Air Force had long sought such an alliance, hoping that it would allow the Atlas V and Delta IV to operate in parallel, keeping both viable, reducing cost overheads and avoiding an unnecessary duplication of effort.
Sitting on Pad 41 at the Cape on 18 June, the Atlas V destined to fly the historic 50th EELV mission will be a visually impressive machine. On this occasion, it will not be equipped with any strap-on boosters, but will rely instead upon its common core – 12.5 feet in diameter and 106.6 feet tall – and a Centaur second stage. The core boasts a single RD-180 engine, of Russian design, fed by a refined form of kerosene, known as ‘RP-1’, and liquid oxygen. Two and a half seconds before the countdown clock touches zero, the RD-180 will growl to life.
“…we have ignition…and we have liftoff…”
Ascent into the Florida sky will be dazzling, spectacular…and brisk. Within seconds of clearing the tower, the Atlas will commence its fast climb away from the Cape, quickly attaining maximum thrust and establishing itself on the proper azimuth for its journey into orbit. Thirty-five seconds into the mission, it will burst through the sound barrier, commencing supersonic flight, and shortly thereafter will encounter ‘Max Q’, at which point aerodynamic stresses on the vehicle reach their most acute. By now, the glow of the RD-180 will be a mere dot in the distance; the Atlas having already climbed to an altitude of around 38 miles and achieved a velocity in excess of 4,700 mph.
Three and a half minutes after launch, the bulbous payload fairing will be jettisoned, exposing the National Reconnaissance Office’s NROL-38 satellite to the harsh environment of space for the first time. With the burnout of the common core, a minute or so later, the Centaur – painted white for this mission, to offer thermal conditioning during a lengthy phase of ‘coasting’ – will separate the payload and begin the process of delivering it to its operational orbit. In recent weeks, much speculation has arisen with regard to NROL-38’s nature. Some observers believe it to be a communications data-relay platform, whilst others consider it to a reconnaissance sentinel. Unfortunately, the official mission patch, which bears the fearsome countenance of Anubis, ancient Egyptian god of the dead, does not offer many helpful pointers.
Yet as Anubis weighed the hearts of the dead, to judge the ‘goodness’ and ‘fruitfulness’ of a person’s life, so the success of this Atlas V launch – the 50th EELV – will also be weighed as ULA embarks on the next stage of its career. In fact, the 51st launch, featuring a Delta IV, will fly on 28 June and only last month ULA received a $398 million contract to deliver satellites for the Multi-User Objective System and Global Positioning System. Other potential courses include the Delta IV transporting humans to the International Space Station and, in February 2010, ULA received stimulus funding from NASA under its Commercial Crew Development programme. Last August, Sierra Nevada Corporation selected the Atlas V to loft its Dream Chaser vehicle and Boeing is looking at using the booster for the inaugural flights of its CST-100 crew transportation capsule. Current plans call for the EELV fleet to operate until 2030.Missions » GPS » Missions » MUOS » Muos-1 »