Spaceflight SSO-A: 64 малых КА - Falcon 9 - Vandenberg SLC-4E - 03.12.2018, 18:34 UTC

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ЦитатаSpaceflight preps for first launch of unique orbiting satellite deployers
August 23, 2018 | Stephen Clark

Artist's illustration of the SSO-A mission's free flyers separating fr om the upper stage of SpaceX's Falcon 9 rocket. Credit: Spaceflight

Engineers working for Spaceflight, a Seattle-based launch services company, are in the final steps of preparing for the first launch of new robotic free flyers carrying more than 70 small government and commercial satellites into polar orbit later this year aboard a dedicated flight of a SpaceX Falcon 9 rocket.

The company's specialists earlier this month were finalizing avionics testing on two modules that will shepherd the microsatellites and nanosatellites into orbit, according to Jeff Roberts, Spaceflight's mission director for the SSO-A "SmallSat Express" mission.
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Spaceflight specializes in arranging launches of multiple small satellites on a single rocket, a rideshare concept that spreads the cost of a launch across many customers. The arrangement is particularly helpful for start-up companies and low-budget research institutions, which often can't afford to pay for a dedicated ride into Earth orbit.

But Spaceflight had never purchased the full capacity of a rocket as large as the Falcon 9 before contracting with SpaceX for the SSO-A SmallSat Express mission in 2015.

At the time of the 2015 announcement, Spaceflight officials said the selection of the Falcon 9 would allow some of the mission's satellites, which are owned by U.S. government agencies, to fly on a U.S. launcher fr om a U.S. launch pad.

Three missions funded by the U.S. military are among the largest spacecraft slated to fly on the SSO-A mission later this year. They are STPSat 5, a microsatellite fr om the Air Force's Space Test Program which hosts five experiments, the eXCITe spacecraft funded by the Defense Advanced Research Projects Agency -- DARPA -- and the FalconSat 6 satellite built by students at the Air Force Academy.

The roster of satellites with reservations on the SSO-A mission has changed numerous times over the last three years as some payloads ran into development delays or found other launch opportunities.

Curt Blake, president of Spaceflight, said in a recent interview that the manifest of satellites on the SSO-A is "pretty much finalized" at 71 spacecraft.

Artist's illustration of the SSO-A mission's free flyers separating from the upper stage of SpaceX's Falcon 9 rocket. Credit: Spaceflight

Most of the satellites on the SSO-A mission, which include 15 microsatellites and 56 CubeSats, will be installed on two free flyers at Spaceflight's facility in Auburn, Washington, near Seattle, officials said.

A few of the larger passengers on the SSO-A mission will be shipped directly to the Falcon 9 launch site at Vandenberg Air Force Base in California, wh ere technicians will mate them to the free flyers, or directly on the rocket's second stage.

Spaceflight officials said the launch is scheduled some time between Oct. 1 and Dec. 31. Several engineers with payloads flying on the SSO-A mission said they expected the launch in November, after a pair of Falcon 9 launches earlier in SpaceX's queue at Vandenberg with Argentina's SAOCOM 1A Earth observation satellite and the final set of 10 Iridium Next voice and data relay satellites.

The deployment structure developed by Spaceflight consists of two hubs -- an upper and a lower free flyer -- carrying satellites and CubeSat dispensers. Both free flyers will separate from the Falcon 9 rocket once it enters a polar, sun-synchronous orbit around 357 miles (575 kilometers) above Earth.

Blake said the free flyers are based on Spaceflight's Sherpa space tug, which the company intended to launch for the first time on a Falcon 9 flight shared with Taiwan's Formosat 5 Earth observation satellite. But delays in Formosat 5's launch, caused in part by a Falcon 9 rocket explosion on a launch pad in 2016, prompted Spaceflight to cancel the mission and find alternative launch opportunities for the smallsats reserved on the Sherpa flight.

The Formosat 5 mission finally launched last August.

"Generically, we call it the Sherpa," Blake said of the SSO-A mission in an interview with Spaceflight Now earlier this month. "But it is actually more than one hub. There's an upper free flyer and and a lower free flyer. There's a lot of spacecraft on each of those. It's kind of a combination stack."

This infographic released by Spaceflight illustrates the types of payloads booked on the SSO-A mission. Credit: Spaceflight

The pace of work at Spaceflight's integration facility in Washington is picking up as satellites begin arriving.

"It's very busy," Blake said. "It's a pretty well orchestrated logistical exercise. Our focus in integration has a very involved schedule. It has different spacecraft arriving at different points. If their teams are involved, then they arrive as well. Once integration occurs, then they vacate and the next folks come in."

Blake said the entire payload riding into orbit on the Falcon 9 rocket will weigh around 4 metric tons -- nearly 9,000 pounds -- at the time of launch.

"We'll be integrating just about all of the CubeSats and a couple of microsats up at Auburn," Roberts told Spaceflight Now. "So we're getting ready for that event, making sure that we have all of our customers have all of their documentation complete and ready.

"We've done mission readiness reviews with our customers. The last thing we need to do is give them their shipping dates," he said. "We'll do that once we have confirmation of our launch date. We'll have customers show up around 60 days before launch up at Auburn. We'll do integration for about two or thee weeks up there, and then we'll package everything and ship it down to Vandenberg for the final 30 days of the launch campaign."

The free flyers will carry 67 of the satellites slated to fly on the SSO-A mission. Another four microsatellites will be mounted directly on the Falcon 9 rocket, which will command their separation sequences.

Once in orbit less than 15 minutes after liftoff, the Sherpa modules will release from the rocket and begin releasing the smallsats, Roberts said.

"We've developed a deployment sequence that's based off a high-fidelity analysis that we did specifically to make sure our customers don't collide into each other upon deployment, so we're taking our time," he said. "It's about a six-hour deployment sequence. We make sure that we phase that to maximize the distance in separation between all of our customers."

That should help the U.S. military, which tracks objects in orbit, more quickly identify the satellites released on the SSO-A mission, an issue that has caused headaches in the past.

The free flyers will operate as independent spacecraft themselves, with their own computers, electronics and batteries.

"We refer to them as free flyers because that's exactly what they are. There is no propulsion system on-board. They just simply hold all the avionics and the dispensers to command deployment," Roberts said.

The upper free flyer is based on a commonly-used secondary payload adapter -- known as an ESPA ring -- built by Moog. The lower free flyer is Spaceflight's own design, according to Roberts.

The free flyer modules will unfurl drag sails after the satellite deployments to help bring the dispensers back into Earth's atmosphere.

Of the 71 satellites booked on the SSO-A mission, more than 30 are from international customers, according to Spaceflight. Organizations from 18 countries have payloads on the SSO-A mission: the United States, Australia, Italy, Netherlands, Finland, South Korea, Spain, Switzerland, United Kingdom, Germany, Jordan, Kazakhstan, Thailand, Poland, Canada, South Africa, Brazil, and India.

Planet is one of major commercial customers on the mission, with two of its SkySat microsatellites and several Dove CubeSats set to join its large fleet of Earth-imaging craft in orbit. Planet is also sponsoring the launch of two CubeSats from the Georgia Institute of Technology and the University of Colorado in Boulder's Laboratory for Atmospheric and Space Physics.

"Among the spacecraft onboard, 23 are from universities, 19 are imaging satellites, 23 are technology demonstrations, two are art exhibits, and one is from a high school. Seventy-five percent are commercial spacecraft," Spaceflight said in a statement.

Blake told Spaceflight Now the SSO-A mission turned out to be a complex undertaking.

"To fill, or to make profitable buying a rocket the size of Falcon 9, you have to aggregate a lot of small spacecraft," he said. "Just understanding what kind of timescale that's going to take and how many satellites you're going to have to aggregate to hit that one point in time -- that's one lesson -- just understanding wh ere that is, and how difficult it is.

"The second one is during the timeframe as you're getting ready, different customers have different potential issues," he added. "Some float through as easy as can be. Others may have difficulties along the way. We've had to move different customers around on the stack. That means that you really need to have an ability to configure and reconfigure the stack, (and) the electronics that go into the deployments."

File photo of a Falcon 9 launch from Vandenberg Air Force Base, California. Credit: NASA/Bill Ingalls

Spaceflight, a division of Spaceflight Industries, has arranged the launch of more than 140 smallsats to date on numerous missions using a variety of launchers, including the Falcon 9, India's Polar Satellite Launch Vehicle, Northrop Grumman's Antares booster, the Russian Soyuz rocket, and the now-retired Dnepr rocket.

The record number of satellites launched on a single rocket is 104, set by an Indian PSLV mission last year. Some of those payloads were customers of Spaceflight, but not all.

Blake said Spaceflight has no immediate plans to buy another dedicated Falcon 9 launch. The economical and logistical sweet spot for rideshares may be using a smaller rocket, he said.

"We're making sure to see how this one goes, and getting all the lessons learned out of it, before turning our attention to doing another one this large," Blake said. "Having said that, we're actively looking at different ones on medium-sized launch vehicles.

The company has agreements for future smallsat rideshare launches on Arianespace's Vega rocket, Rocket Lab's Electron, and Virgin Orbit's air-dropped LauncherOne vehicle -- all significantly smaller, and less expensive, than a Falcon 9, which currently sells for around $50 million to $60 million per flight.

"We know about aggregating a number of payloads onto small launch vehicles," Blake said. "You can think of those as dedicated missions as well, wh ere we've got five or 10 different spacecraft on a smaller launch vehicle, 30 or 40 on a medium-sized launch vehicle. The thing we'll take time to sort out is how it goes on a large launch vehicle like this."

Two SkySat Satellites, Three Doves, And A Record-Breaking Launch On Spaceflight's SSO-A
Mike Safyan | October 22, 2018

Two SkySat Satellites, Three Doves, and a Record-Breaking Launch on Spaceflight's SSO-A

Planet is gearing up to send seven satellites into orbit this November as part of SSO-A: SmallSat Express, a fully dedicated rideshare mission on the SpaceX Falcon 9, procured by Spaceflight Industries. Of the 70 spacecraft onboard, Planet will send up two SkySat satellites, three latest-generation Dove satellites (Flock 3s), and two university cubesat projects sponsored by Planet.

The two SkySat satellites - numbers 14 and 15 - are the primary spacecraft of the SSO-A mission. They will join the 13 operational SkySats in orbit, expanding the world's largest fleet of high-resolution imaging satellites. The improved global coverage, particularly in the morning orbit, will help Planet increase access to high-resolution imagery for customers as well as task afternoon imaging more effectively. This is the first time SkySat satellites will fly on a Falcon 9.

The three Dove satellites on this launch will support Planet's global monitoring mission and highlight our agile aerospace approach of rapid iteration of satellite technology. Planned upgrades to the Doves, such as improved camera and telescope systems, will be tested in flight and refined back on the ground in our new satellite manufacturing facility.

Planet is also sponsoring the launch of two university cubesat projects: the MinXSS-2 from the University of Colorado, Boulder Laboratory for Atmospheric and Space Physics and the RANGE from Georgia Tech. These projects were the finalists of the University CubeSat Partnership, a competition hosted by Terra Bella (before its acquisition by Planet in 2017).

We're excited to participate in this record-breaking launch with Spaceflight Industries! Stay tuned for updates from the launch site at Vandenberg by following @planetlabs.


ЦитатаMichael Baylor‏ @nextspaceflight 26 мин. назад

Koenigsmann said at the IAC that the SSO-A mission would likely feature a third flight of the same first stage.
ЦитатаEric Berger‏Подлинная учетная запись @SciGuySpace 37 мин. назад

Lars Hoffman, of SpaceX, just said at the VonBraun symposium that, "We're about to relaunch a booster for the third time." No additional details. Hopefully @jeff_foust can grab him for details after the panel.

ЦитатаMaxar's SSL Delivers Two Earth Observation Satellites to Vandenberg Launch Base
October 25, 2018

 SSL advances its growing leadership in the manufacturing of small form-factor satellites
PALO ALTO, CA, Oct. 25, 2018 /PRNewswire/ - SSL, a Maxar Technologies company (NYSE: MAXR) (TSX: MAXR), and a leading provider of innovative satellites and spacecraft systems, has shipped two Earth observation satellites to Vandenberg Air Force Base where they will be launched on Spaceflight's first Sun Synchronous dedicated rideshare mission aboard a SpaceX Falcon 9 launch vehicle. SSL manufactured SkySat 14 and 15 for commercial Earth observation company Planet, advancing SSL's leadership in the manufacture of innovative, small form-factor satellites.

The imaging satellites feature 72 cm resolution and will be added to Planet's SkySat constellation, which currently includes 11 SSL-built small satellites. The SkySat constellation complements Planet's Dove constellation, with the most satellites on orbit from a commercial imagery provider.
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"SSL continues to embrace innovation and elevate our partnerships to meet the rising demand for small form-factor satellites," said Dario Zamarian, Group President, SSL. "It has been rewarding to apply our extensive expertise in the manufacturing of high-quality small satellites, solidifying our leadership position and supporting the Planet team in achieving its objectives."

Six of Planet's SSL-built satellites were launched in 2017 and five were launched in 2016. SSL continues to manufacture additional SkySats for Planet in its state-of-the-art SmallSat manufacturing facility, integrating improvements and increasing the cadence of delivery.

"Working alongside SSL on our Earth imaging fleet has been very successful," said Chester Gillmore, Vice President of Manufacturing at Planet. "Adding two more SkySats to our fleet will enhance our daily monitoring to help our customers gain valuable insights, understand what's happening on the ground and take needed and timely action."

SSL combines a commercial mindset with a track record of reliability in building smaller form-factor satellites for both Earth Observation and communications. Blending speed and agility with space proven qualification and production processes provides satellite operators with high performance and best value solutions.



ЦитатаThis year, Spaceflight will be executing the company's first-ever dedicated rideshare mission on a SpaceX Falcon 9 from Vandenberg Air Force Base. This historic mission, named SSO-A: SmallSat Express, will be the largest mission from a U.S.-based launch vehicle.
Spaceflight manifested this entire mission with more than 60 payloads from 17 different countries from across more than 30 organizations.
This will be an important and unique launch for Spaceflight. Increasing access to space has always been Spaceflight's mission as an organization, and rideshare represents a viable solution to the many hurdles present in accessing space, including availability, cost, and other factors.
Dedicated rideshare missions address those challenges in an expedited fashion, flying large amounts of spacecraft to orbit at one time; the mission is also solely dedicated to smallsats.
The Future of Launch
While SSO-A: SmallSat Express has not yet launched, there are already several important lessons learned from this mission
First is that a large number of satellites on one launch is an incredibly complex undertaking. Complexity touches every part of rideshare missions, including integrating payloads, placing multiple satellites on orbit, and managing regulatory needs. Now, with more than 60 payloads on a single mission, the complexities are amplified.
It's too early to completely rule out large vehicles for future dedicated rideshare missions; however, it is more likely that small- and medium-sized launch vehicles will become the vehicles of choice for future dedicated rideshare missions.


ЦитатаPirat5 пишет:
предварительный состав, в соответствии с Гюнтером и reddit 
KazSTSAT весит 105 кг, а не 50



Про static fire никто не забыл, но новой информации пока нет. Ждём сегодня в ночь...
Static fire on Thursday (Nov 15th). Since it is a more hidden pad we'll have to wait for SpaceX's tweet for confirmation of the static fire.
Ловить обтекатель пока не хотят
ЦитатаNo fairing recovery for SSO-A, next try will be with Iridium-8.


ЦитатаChris B - NSF‏ @NASASpaceflight 17:14 - 15 нояб. 2018 г.

Falcon 9 B1046.3 has arrived at SLC-4E for her static fire test ahead of launch on Monday with the SSO-A mission.


ЦитатаSpaceX‏Подлинная учетная запись @SpaceX 21:55 - 15 нояб. 2018 г.

Static fire test of Falcon 9 complete--targeting November 19 launch of Spaceflight SSO-A: SmallSat Express from Vandenberg Air Force Base in California.


ЦитатаSpaceX‏Подлинная учетная запись @SpaceX 21:59 - 15 нояб. 2018 г.

Falcon 9's first stage booster for this mission completed two East Coast launches earlier this year.


ЦитатаStephen Clark‏ @StephenClark1 5:09 - 16 нояб. 2018 г.

Next: Installation of Spaceflight's free flyers on the Falcon 9, carrying 64 smallsats. Launch set for 10:31:47am Pacific Time on Monday.
18:31:47 UTC 19.11.2018


ЦитатаLeaf Space‏ @leaf_space 9:18 - 16 нояб. 2018 г

We're ready to launch!
Two of our #LeafLine GSs are ready to autonomously support Launch & Early Operation Phase for customers flying on #SSOA @SpaceflightInc mission of @SpaceX #Falcon9.
Stay tuned!


ЦитатаEuropean Student Earth Orbiter animation

European Space Agency, ESA

Опубликовано: 16 нояб. 2018 г.

The ESEO satellite will be set into space on board the Spaceflight's SSO-A: SmallSat Express dedicated rideshare mission on a SpaceX Falcon 9 launcher from the Vandenberg Air Force Base in California, (US), on 19 November 2018. ESEO will be a passenger together with about 70 other micro, nano, and pico satellites from several countries from all over the world.
 Скрытый текст:
ESEO is an ESA micro-satellite project with an educational objective: for the participating university students to acquire hands-on experience of a real space project, in order to prepare a well-qualified technical workforce for the European space sector. This was achieved by offering the student the opportunity to develop the payload (scientific instruments or technology demonstration experiments), key satellite subsystems and the ground segment (ground stations and Mission Control) to the mission, under the coordination of ESA and SITAEL, the Industrial Prime Contractor, responsible for the satellite platform, system integration and testing, and the technical coordination of the student teams.

Run by the ESA Education Office, ESEO is part of ESA Academy's Hands-on Space Programme.

Ten Universities from eight ESA Member States (Estonia, Germany, Hungary, Italy, Netherlands, Poland, Spain, UK) have participated in ESEO, with more than 600 university students involved in the project since its inception.

The ESEO mission will validate in-orbit the SITAEL S-50 platform (50kg including the payload), the smallest within the SITAEL products portfolio, and hence it represents a crucial milestone of the intensive hard work in designing, developing and manufacturing innovative multi-purpose small satellites platforms. (4:55)


ЦитатаEuropean Student Earth Orbiter ready for launch

European Space Agency, ESA

Опубликовано: 16 нояб. 2018 г.

The European Student Earth Orbiter (ESEO) is an educational micro-satellite, which involved European university students during the whole project lifecycle. This 50-kilogram microsatellite is now ready and waiting for launch on 19 November aboard a SpaceX Falcon 9 launcher from California.

The student teams developed experiments on board ESEO include cameras for Earth imaging, a radiation dosimeter, a plasma detector, and demonstrators of technologies that can be used for future education satellite missions. (4:53)


LIVE: запуск ракеты Falcon 9 с уже дважды использованной ступенью

Девятнадцатого ноября, в 21:31 должен состояться запуск ракеты Falcon 9 в рамках миссии SSO-A: SmallSat Express
Пуск многоразовой ракеты произведут с базы Ванденберг, стартового комплекса SLC-4E. В рамках него на солнечно-синхронную орбиту намерены вывести 64 малых спутника от 34 различных организаций из 17 стран. Организатор старта -- Spaceflight Industries.

 Крупнейший заказчик -- компания Planet: ее аппараты будут проводить мониторинг земной поверхности. Также среди заказчиков -- компании HawkEye 360, Capella, Astrocast и многие другие.

 Кроме коммерческой составляющей, миссия призвана выполнять и научные задачи. На орбиту намерены вывести сразу несколько экспериментальных аппаратов, построенных различными университетами.

Для широкой общественности миссия SSO-A: SmallSat Express интересна прежде всего тем, что для нее намерены использовать первую ступень B1046.3, которая уже дважды побывала на орбите.


Цитатакукушка пишет:
ервую ступень B1046.3, которая уже дважды побывала на орбите
На какой орбите она побывала?


18.11.2018 00:18:22 #17 Последнее редактирование: 18.11.2018 00:26:48 от tnt22
Пуск отложен...
ЦитатаSpaceX‏Подлинная учетная запись @SpaceX 13:02 - 17 нояб. 2018 г.

Standing down from Monday's launch attempt of Spaceflight SSO-A: SmallSat Express to conduct additional pre-flight inspections. Once complete, we will confirm a new launch date.
О5 же, по слухам, пуск после Дня Благодарения (4-й четверг ноября, в 2018 г - 22 ноября)
ЦитатаStephen Clark‏ @StephenClark1 13:06 - 17 нояб. 2018 г.

Hearing this is likely to slip until after Thanksgiving.

NOVEMBER 15, 2018

Globals are ready to go!

The BlackSky constellation is taking shape. We're very excited for our first two Global satellites to be on orbit by the end of the month. Global-2 will be first, heading to orbit aboard the Spaceflight SSO-A Smallsat Express mission on a Falcon 9 rocket from Vandenberg Air Force Base. ...

ЦитатаSpaceX postpones rideshare launch from California
November 17, 2018Stephen Clark

Artist's illustration of Spaceflight's free flyers and payloads on the Falcon 9 rocket's second stage. Credit: Spaceflight

SpaceX has ordered additional inspections on a Falcon 9 rocket at Vandenberg Air Force Base in California set to launch 64 small satellites, a decision that is expected to keep the launcher grounded for several days until after the Thanksgiving holiday, officials said Saturday.
 Скрытый текст:
The Falcon 9 was supposed to take off Monday from Vandenberg -- a military base around 140 miles northwest of Los Angeles -- but SpaceX announced the postponement in a tweet Saturday.

"Standing down from Monday's launch attempt of Spaceflight SSO-A: SmallSat Express to conduct additional pre-flight inspections," SpaceX tweeted. "Once complete, we will confirm a new launch date."

The Falcon 9 rocket will launch 64 satellites on a rideshare mission arranged by Spaceflight, a launch broker for smallsats based in Seattle. The 64 payloads, ranging in size from a Rubik's cube to a refrigerator, are owned by a variety of U.S. and international operators, including the U.S. government, research institutions, and commercial companies.

The launch will set a record for the most satellites ever deployed in orbit on a U.S. rocket, but it will fall short of the global mark of 104 spacecraft launched on an Indian rocket last year.

The upcoming launch is also noteworthy because it will be SpaceX's first flight to reuse the same Falcon 9 first stage booster a third time.

The booster assigned to Spaceflight's SSO-A rideshare mission flew two times from Florida: On May 11 from NASA's Kennedy Space Center with the Bangladeshi Bangabandhu 1 communications satellite, and again Aug. 7 from Cape Canaveral Air Force Station with the Indonesian Merah Putih telecom payload.

On both occasions, the first stage landed on SpaceX's drone ship in the Atlantic Ocean and returned to port for inspections, some limited refurbishment and reuse.

File photo of a SpaceX Falcon 9 rocket on the launch pad at Vandenberg Air Force Base, California, before a previous mission. Credit: SpaceX

SpaceX has re-launched a previously-flown first stage booster 17 times, most recently on Thursday's launch from the Kennedy Space Center in Florida with Qatar's Es'hail 2 communications satellite. But all of the first stages to date have only flown twice.

That changes with SpaceX's next mission as the company aims to eventually reuse Falcon 9 boosters up to 10 times without refurbishment, and up to 100 times with periodic overhauls. The latest iteration of the Falcon 9 design, commonly known as the "Block 5" version, includes upgrades over earlier designs to make reusing the rockets easier.

SpaceX plans to recover the first stage again aboard its West Coast drone ship in the Pacific Ocean after Spaceflight's multi-satellite launch.

Several people working with the payloads on the rideshare mission said the delay was ordered by SpaceX to resolve concerns with the rocket.

One official with a company that owns payloads set to ride to orbit on the Falcon 9 rocket said the launch will be delayed until after Thanksgiving, and another customer on the SSO-A launch said in a tweet that the flight will be delayed by five or six days.

"Unfortunately, the (Spaceflight SSO-A) launch is delayed by 5-6 days due to some additional inspections of the SpaceX rocket," officials tweeted from an account associated with the MinXSS 2 CubeSat mission flying to orbit on the Falcon 9.

The satellites riding on the flight include 15 microsatellites and 49 CubeSats. Seven CubeSats were not ready in time for a November launch, and technicians replaced them with ballast that will stay aboard Spaceflight's dual deployment modules, ensuring mass and balance calculations for the launch remain unaffected, according to Jeff Roberts, Spaceflight's mission manager for the SSO-A mission.

The microsatellites and CubeSats come from 17 countries: the United States, Australia, Italy, the Netherlands, Finland, South Korea, Spain, Switzerland, the United Kingdom, Germany, Jordan, Kazakhstan, Thailand, Poland, Canada, Brazil, and India.

Rockets typically launch with one or two primary satellites, and sometimes carry additional secondary payloads to fill unused capacity, but the SSO-A launch follows a different model.

There are no primary payloads on the SSO-A mission. Spaceflight purchased the full capacity of the Falcon 9 launch in 2015, and satellite owners booked their launch contracts with Spaceflight, not with SpaceX.

Spaceflight has brokered rideshare launches on rockets before, including India's PSLV and Russia's Soyuz, but those missions flew on launches carrying bigger satellites in the primary payload slot.

The rideshare arrangement allows satellite owners to divide the cost of a rocket launch, instead of paying for the entire mission.

SpaceX test-fired the Falcon 9 rocket Thursday night at Vandenberg in a customary pre-flight countdown test at Space Launch Complex 4-East. Technicians planned to return the rocket to a nearby hangar for attachment with the SSO-A payload stack, which was already encapsulated inside the Falcon 9's nose fairing.

Spaceflight's unique spacecraft carrier modules, named the upper and lower free flyers, will separate from the Falcon 9's upper stage in a roughly 357-mile-high (575-kilometer) orbit after liftoff from Vandenberg.

"We refer to them as free flyers because that's exactly what they are. There is no propulsion system on-board. They just simply hold all the avionics and the dispensers to command deployment," Roberts said.

The upper free flyer is based on a commonly-used secondary payload adapter -- known as an ESPA ring -- built by Moog. The lower free flyer is Spaceflight's own design, according to Roberts.

Four of the microsatellites launching on the SSO-A mission will separate directly from adapter plates on the Falcon 9 second stage after it arrives in orbit. The other 60 will deploy from the free flyers in a timed sequence over the next five hours.

The free flyer modules will unfurl drag sails after the satellite deployments to help bring the dispensers back into Earth's atmosphere.

"Everyone is integrated, the entire structure has been encapsulated, and SpaceX has broken over (turned) the encapsulated structure horizontal in preparation for mating to the rocket," Roberts told Spaceflight Now.

The total mass of the free flyers and payloads launching on the SSO-A mission is around 8,800 pounds, or 4 metric tons.

With all the satellites now aboard the free flyer modules, there are no plans to delay the launch if engineers detect a problem with one of the payloads. It's a hands-off approach crafted to ensure a problem with one satellite does not affect the others.

"At this point, the train is still leaving the station," Roberts said in an interview.
The launch window each day opens at 10:31:47 a.m. PST (1:31:47 p.m. EST; 1831:47 GMT) and runs nearly a half-hour. There's a chance the liftoff time could be adjusted within the launch window based on calculations on the day of launch to avoid a chance one of the spacecraft could collide with an object already in space.
 Скрытый текст:
The launch caps a feverish two months of work installing the satellites on the dispensers at Spaceflight's facility in Auburn, Washington, then shipping the modules by road to Vandenberg. Eleven microsatellites were shipped directly to Vandenberg by their manufacturers -- and added to the payload stack there -- because they could not be transported by road when fueled with propellant.

"I'm really excited, and that's pretty much how the team feels, too," Roberts said. "This is the culmination of almost three years of work by this team, and in the last 60 days, many people on this team have been working 12-to-16 hours per day, seven days per week, so they put a lot of effort to make this successful for us and for all of our customers.

"We're excited to see this go on orbit and be successful."