The darkened skies over Cape Canaveral Air Force Station, Fla., were broken this morning with a rousing, pre-dawn liftoff of the ninth of 12 planned United Launch Alliance (ULA) missions of 2015, carrying Mexico’s Morelos-3 communications satellite to Geostationary Transfer Orbit (GTO). Liftoff of the 195-foot-tall (59.4-meter) Atlas V—flying for only the fifth time in its “421” configuration, equipped with a 13-foot-diameter (4-meter) Payload Fairing (PLF), two Aerojet-built, solid-fueled boosters and a single-engine Centaur upper stage—occurred at 6:28 a.m. EDT from the Cape’s storied Space Launch Complex (SLC)-41, at the end of a 20-minute “window”. In doing so, it kicked off ULA’s 100th mission since the formation of the Centennial, Colo.-headquartered organization, back in December 2006.
Over the course of the following three hours, the Russian-built RD-180 engine of the Atlas V’s first stage and two “burns” of the RL-10C restartable engine of the Centaur upper stage delivered Morelos-3 toward a GTO “target point” of 2,978 x 22,236 miles (4,792 x 35,785 km). When fully operational, Morelos-3 has an expected lifetime of 15 years and will provide secure communications for Mexico’s national security needs, as well as enhanced coverage for the country’s civil telecommunications.
As outlined in AmericaSpace’s Morelos-3 preview article, this mission represents only the third commercial comsat ever launched by ULA in its almost nine years of operations. It follows on the heels of the 14,625-pound (6,634 kg) ICO-G1—which was the largest and most massive commercial comsat in the world at the time of its April 2008 launch—and Intelsat-14, lofted in November 2009. It has been suggested that ULA’s high costs have deterred it from winning other commercial comsat contracts, although the Air Force’s recent “block buy” of 36 Atlas V and Delta IV booster cores in support of its national security requirements have reportedly begun to drive costs down by as much as 20 percent. ULA hopes that this will yield up to two commercial comsat contracts per annum from 2015 and, last August, the company signed a deal to deliver Echostar Corp.’s Echostar XIX high-speed satellite internet comsat into orbit atop an Atlas V sometime in the fall of next year.
The launch of Morelos-3 was executed atop the fifth flight of the sparingly-used Atlas V 421, which carries the capability to deliver up to 31,012 pounds (14,067 kg) into low-Earth orbit and up to 15,190 pounds (6,980 kg) to GTO. Putting this into context, Morelos-3’s mass at liftoff was about 11,740 pounds (5,325 kg), placing it within the top quarter of the 421 payload envelope. Following its structural completion in June 2014, the Boeing-built satellite underwent extensive testing and was transferred from Astrotech’s payload processing facility at the Cape on 25 September. Enshrouded within its bulbous Payload Fairing (PLF), it was installed atop the Atlas V in the Vertical Integration Facility (VIF) at SLC-41, ahead of yesterday’s rollout on the Mobile Launch Platform (MLP) to the nearby pad surface.
However, although weather conditions for Friday’s opening launch attempt remained steady at 70-percent favorable, updated predictions issued on Wednesday by the 45th Weather Squadron at Patrick Air Force Base shed greater concern for the backup launch opportunity on Saturday. In the event of a 24-hour postponement, it was noted that the suitability of weather conditions at T-0 had declined from 80-percent favorable to just 60-percent favorable, owing to the action of Hurricane Joaquin. Situated offshore to the east-southeast of the Cape, Joaquin has continued to intensify and—influenced by an upper-level trough moving into the eastern United States—was passing about 410 miles (660 km) to the east of the Cape during the night of Friday into Saturday. This was expected to lead to an elevated probability of increased winds in the event that the launch slipped to Saturday, making a Friday attempt more critical.
In addition to liftoff winds, solar weather posed another risk. Specifically, the sunspot locality known as Active Region (AR) 2422 harbors energy for powerful X-class solar flares, which are known to cause major radiation storms and worldwide radio communications blackouts. As of Thursday, there existed a 25-percent probability of an X-class flare during the Morelos-3 launch campaign, with a 70-percent likelihood of a medium-sized M-class flare. Earlier this week, AR 2422 was also responsible for severe disruption to low-frequency communications in South America and parts of the Atlantic Ocean. “If a flare occurs” during the Morelos-3 launch campaign, the 45th Weather Squadron explained Wednesday, “the sunspot is in a location that could cause Earthward-directed solar energetic particles.”
Against the backdrop of this uncertain weather outlook both on Earth and on the Sun, efforts to prepare for ULA’s ninth launch of the year—and the company’s 100th overall flight—continued unabated. Last month, the Common Core Booster (CCB) of the Atlas V 421 was mounted onto the MLP, followed by its twin solid-fueled rockets, the “interstage” element and finally the Centaur upper stage. Following the installation of the Morelos-3/PLF stack atop the vehicle, the customary Launch Readiness Review (LRR) was completed on 30 September, around 24 hours ahead of rollout from the VIF to the pad.
Formal countdown operations got underway late Thursday evening, at T-6 hours and 20 minutes, with the activation of the Atlas V’s flight control systems. Ground Command Systems testing occupied about 3.5 hours, as engineers validated communications between the booster and the Launch Control Center (LCC), prior to the loading of liquid oxygen and a highly refined form of rocket-grade kerosene (known as “RP-1”) into the CCB. Since the latter undergoes cryogenic “boil-off” and must be continuously replenished until close to T-0, it was loaded relatively late in the countdown, whereas the RP-1 experiences no leakage or reduction in capacity and had already been pumped aboard the Atlas. Following a built-in hold, authorization was granted about three hours before T-0 to commence liquid oxygen tanking operations.
This loading of cryogenic oxidizer into the CCB and the Centaur passed smoothly through Slow Fill and Fast Fill modes, before transitioning to “Topping”, in order to continuously replenish the effects of boil-off. Shortly afterwards, the Centaur received its liquid hydrogen propellants and was reported as fully loaded about an hour before T-0. Cycling tests of the fill-and-drain valves of the Atlas V and Centaur were completed and, with all tanks confirmed at Flight Level, a final checkout began on the Flight Termination System (FTS). The latter is tasked with remotely destroying the vehicle in the event of a major accident during ascent. Reaching the final built-in hold point at T-4 minutes at 5:34 a.m. EDT, the clock paused for an expected 30 minutes. During this period, the ULA Launch Conductor performed last checks on the vehicle, payload and the weather situation. Morelos-3 was placed on internal power, running off its on-board batteries until such time as it achieved orbit and could begin to draw from its electricity-generating solar arrays.
A final “Go/No-Go” of all stations produced a unanimous “Go” from across the board to proceed with this morning’s launch attempt, and at 6:04 a.m. EDT the clock was released from its hold point at T-4 minutes. During this terminal phase, the FTS was placed onto internal power and armed, the Launch Control System was enabled, the topping of propellants ended and the Atlas V’s on-board systems assumed primary command of all critical functions through liftoff.
“Range Green!” came the call from the Range Operations Co-ordinator (ROC) at T-60 seconds, confirming that all Eastern Range assets were ready to support the launch. However, at T-0:51 seconds a HOLD was called due to a boat that strayed into the exclusion zone offshore of the launch site. The boat did clear the area, the launch team recycled the countdown and reset at T-4 minutes, aiming for liftoff at 6:28 a.m. EDT.
“Chased the boat out” said ULA President and CEO Tory Bruno on his Twitter page.
At T-2.7 seconds, the CCB’s Russian-built RD-180 engine roared to life, its twin nozzles generating a propulsive yield of 860,000 pounds (390,000 kg). As the clock hit T-0, the twin solid-fueled boosters—each standing 67 feet (20.4 meters) tall—ignited, producing a combined thrust of almost 700,000 pounds (316,000 kg) to supplement the initial boost away from SLC-41. Climb-out of the Atlas V commenced at T+1.1 seconds, with the behemoth rising in a stately manner to 85 feet (25.9 meters), after which the avionics of the Centaur upper stage commanded a pitch, roll and yaw program maneuver to establish the stack onto the proper flight azimuth of 104 degrees for the delivery of Morelos-3 into orbit.
After passing Mach 1, the vehicle experienced a period of maximum aerodynamic turbulence on its airframe, known as “Max Q”, about a minute into the flight, and at this point the RD-180 was throttled back and began a nominal zero-pitch and zero-yaw angle of attack to minimize structural loads. At two minutes after liftoff, the twin boosters—their propellant exhausted—were jettisoned and the Atlas V continued flying under the impulse of the RD-180 for a further two minutes, ahead of Booster Engine Cutoff (BECO) at about 250 seconds into the mission. In rapid succession, the CCB separated from the rapidly ascending stack and the first of two “burns” by the Centaur upper stage got underway. Lasting 14 minutes, the burn ended about 18 minutes after liftoff, and was followed by a 2.5-hour period of “coasting”, preparatory to the second burn, which ran for barely a minute. According to ULA’s pre-launch predictions, Morelos-3 was expected to separate from the Centaur at 8:59 a.m. EDT, a little less than three hours after departing the Cape.
“The quality and reliability of the Atlas V is unparalleled, and today it delivered on a critical step toward bringing next-generation mobile telecommunications services to Mexico,” said Steve Skladanek, president of Lockheed Martin Commercial Launch Services. “The placement of Morelos-3 into orbit is vital to an effective Mexsat constellation, and partnering with ULA, we were able to help the customer achieve that mission.”
Flying on behalf of Mexico’s Ministry of Communications and Transportation, Morelos-3 was originally conceived in the summer of 2009 as part of the Mexican Satellite System (MEXSAT). A year later, in December 2010, Boeing signed contracts worth about $1 billion with the Mexican Government to build three satellites, two ground sites, associated network operations systems and reference user terminals. It was stressed at the time that MEXSAT would “provide secure communications for Mexico’s national security needs, as well as enhanced coverage for the country’s civil telecommunications”. Under the terms of the contract, two Mobile Satellite Services (MSS) spacecraft—MEXSAT-1 and MEXSAT-2—would utilize Boeing’s 702HP “bus”, powered by a pair of five-panel gallium arsenide solar arrays and each equipped with a 72-foot (22-meter) L-band reflector for mobile satellite services and a 6.6-foot (2-meter) Ku-band antenna. A third satellite, MEXSAT-3, would be built by Orbital Sciences Corp. Smaller than its siblings, and weighing 6,393 pounds (2,900 kg) at launch, it was designated the “Fixed Satellite Services” (FSS) member of the trio and is based on Orbital’s Star 2.4 bus, fitted with 12 Ku-band and 12 C-band transponders to provide “full coverage of Mexico and its patrimonial seas and relay civil communications for socioeconomic development”.
The Orbital-built spacecraft, MEXSAT-3, was successfully launched atop an Ariane 5 booster from the Guiana Space Centre in Kourou, French Guiana, in December 2012, and is presently situated at 114.9 degrees West longitude. It was later renamed “Bicentenario”, in honor of the 200th anniversary of Mexico’s declaration of independence from Spain. However, the second-launched satellite, MEXSAT-1—also known as “Centenario”, marking the centenary of the 1910-1920 Mexican Revolution—met with less success. Its construction was completed in November 2013 and it was lofted atop an International Launch Services (ILS) Proton-M booster from the Baikonur Cosmodrome in Kazakhstan on 16 May 2015, but was lost about 490 seconds into the flight, due to a third-stage malfunction.
In the meantime, MEXSAT-2 also received another name, but rather than one which honored a centenary or bicentenary, it was dubbed “Morelos-3”, providing a tangible link with three previous generations of Boeing-built and Mexican-owned communications satellites: Morelos-1 and Morelos-2, launched by the shuttle in June and November 1985, and Solidaridad-1 and Solidaridad-2, launched atop Ariane 4 boosters in November 1993 and October 1994. When operational, Morelos-3 is expected to occupy an orbital “slot” at 116.8 degrees West longitude.