SpaceX Falcon 9

[bavv]

Upgraded Falcon 9 First-Stage Static Fire | 9/21/15

[Apollo13]

http://www.nasaspaceflight.com/2015/09/full-thrust-falcon-9-stage-testing-mcgregor/

The first "Full Thrust" Falcon 9 first stage has begun a test sequence that is involving two static fires on a new test stand at SpaceX's test facility in McGregor, Texas. The stage, unofficially assigned to the launch of the SES-9 satellite in November, underwent a short 15 second firing, ahead of a full duration static fire test that is expected to take place in October.

Falcon 9 Testing:
SpaceX is currently working towards a Return To Flight target of November, following the loss of the previous Falcon 9 mission with the CRS-7 Dragon spacecraft.



Launching on the upgraded Falcon 9, previously cited as the "Falcon 9 v1.2″ in the media – but internally known as the "Falcon 9 v1.1 Full Thrust" – the RTF mission is understood to involve the launch of the SES-9 telecommunication satellite.
SpaceX won't be drawn on confirming when SES-9 will be launched in the sequence of upcoming missions, citing it is the responsibility of the customer to make such an announcement.
Although SpaceX is still conducting its investigation into the CRS-7 failure, a large amount of work is being undertaken with the preparation of launch hardware for the upcoming missions, which will allow the company to hit the ground running when it ready to return to launch action.



Information (L2) noted that one F9 first stage and interstage had already been shipped out of the factory as of late August , en route to McGregor.
That stage has since arrived in Texas and was erected on the "Falcon Heavy Test stand" (L2) – a dual-purpose stand that can be used for both Falcon Heavy and Falcon 9 testing.
It is currently the only test stand that can be utilized for the upgraded Falcon 9's slightly increased length while the original stand prepares to be upgraded.
Guarded by the "Rocket Cows of McGregor" – the stage was soon expected to undergo a 15 second static fire test, although there is no set time for the short test. The initial target was delayed, prior to a scrub, before a realigned test target in the second half of September.
UPDATE: Static Fire has now occurred.
A test – lasting around 30 seconds – was observed earlier the month, although this did not involve the Falcon 9 stage.
It is currently unknown if this was a Merlin 1D test or a second stage test firing, although further evaluations point to it being a single Merlin 1D static fire test.



Now the first stage static fire test has been initiated, it marked the first time an upgraded Falcon 9 first stage has fired up its nine engines.
The final static test will be a Full Duration Firing, currently scheduled to take place in mid-October. The Stage will then be transported by truck to Cape Canaveral for launch preparations.
With the RTF manifest still evolving, preliminary planning dates are now showing the SES-9 mission to launch in the second half of November, with the 20th cited as the latest date (L2). SES later noted they are hoping for November 17, all but confirming they will be the first to fly as Falcon 9 RTF.
Mr. Musk also noted – on September 24 – that SpaceX is six to eight weeks away from RTF during his meetings in Berlin.

Due to SpaceX's ongoing investigation into the CRS-7 failure a solid schedule is not expected for some weeks. However, with the SES-9 date moving to the right on the preliminary planning schedule, the following missions are expected to follow suit.
The return of Dragon missions to the International Space Station (ISS) – on the CRS-8/SpX-8 mission – remains in flux, with the mid-November date cited by NASA managers now increasingly looking like it will move to December or even into 2016.



The latest planning date from this week claimed December 6 is under evaluation, while talk from ESA partners claim the mission could be pushed into 2016 to provide extra flexibility to Cygnus' return on the ORB-4 mission in December. NASA is expected to make a planning decision on targetting November, December or 2016 in the near future.
The latest preliminary schedule information also cites the ORBCOMM-2 mission is being evaluated for a December 21 launch slot, with Jason-3 likely to move into 2016. Jason-3 will launch on the last remaining Falcon 9 v1.1 from the Vandenberg Air Force Base in California.
SES-9, ORBCOMM-2 and the CRS-8 Dragon will all ride on the upgraded Falcon 9 from SpaceX's Cape Canaveral base at SLC-40.



This Cape pad complex – along with SpaceX's Pad 39A at the Kennedy Space Center – will have a LOX densification system on site, allowing the LOX to be super chilled to 1 degree above the triple point.
This process will be achieved by chilling the LOX (-297 degrees F) with LN2 (-320 degrees F). This will raise the LOX density from 70 pounds per cubic foot to 75 pounds per cubic foot, about a 7 percent increase in density.
This will aid the Merlin 1D's increase in performance, which has been in the planning for SpaceX since the new engine started life with the Falcon 9 v1.1.

[Apollo13]

The latest preliminary schedule information also cites the ORBCOMM-2 mission is being evaluated for a December 21 launch slot, with Jason-3 likely to move into 2016. Jason-3 will launch on the last remaining Falcon 9 v1.1 from the Vandenberg Air Force Base in California.
SES-9, ORBCOMM-2 and the CRS-8 Dragon will all ride on the upgraded Falcon 9 from SpaceX's Cape Canaveral base at SLC-40.

Старый Фалкон действительно остался только один.

[Salo]

http://www.americaspace.com/?p=86711

Enhanced Falcon 9 Booster Raises Excitement, Concern, As Return to Flight Date Nears       
By Ben Evans

The performance enhancements which have enabled the Falcon 9 v1.2 (internally known as the Falcon 9 v1.1 Full Thrust) are expected to support larger payloads to orbit and will also permit the landing of the first-stage hardware on the Autonomous Spaceport Drone Ship (ASDS). Photo Credit: SpaceX
 
Three months after the catastrophic loss of its Commercial Resupply Services (CRS)-7 Dragon cargo mission to the International Space Station (ISS)—which appeared to have fallen victim to a failed helium tank strut, provided by an external supplier—SpaceX stands ready to resume launches of its workhorse Falcon 9, albeit in a heavily modified form, perhaps as soon as mid-November. Last week, a successful 15-second static firing of the upgraded "Merlin 1D+" engines, destined for the Falcon v1.2 (internally known as the "Falcon 9 v1.1 Full Thrust") variant of the vehicle, shook the ground of the new Falcon Booster Test Stand at SpaceX's facility in McGregor, Texas, for the first time. Although SpaceX previously stressed that no provisional date had been released for the Falcon 9's Return to Flight (RTF) mission, recent comments by CEO Elon Musk in Berlin indicate that another launch might be attempted within six to eight weeks.
The flight—which will likely transport the SES-9 communications satellite into Geostationary Transfer Orbit (GTO) on behalf of the Luxembourg-headquartered SES satellite services provider and operator—is expected to use the v1.2, whose first-stage Merlin 1D+ and second-stage Merlin 1D+ Vacuum engines will run at their full, 100-percent power level. This is in contrast to the 80 percent of rated performance seen on previous v1.1 missions. A further 13 percent of additional performance will be accrued through a range of structural enhancements to the vehicle's airframe and a process of "densifying" and thereby increasing the liquid oxygen propellant load. All told, this is expected to yield a performance "gain" of 33 percent over the earlier v1.1.

The nine plumes of the Merlin 1D engines flare as the CRS-7 vehicle disintegrates on 28 June. The maiden voyage of the Falcon 9 v1.2 ("Full Thrust"), carrying the SES-9 payload, was scheduled to follow CRS-7 in July 2015. Photo Credit: Alan Walters/AmericaSpace
 
The loss of CRS-7 on 28 June broke a chain of 13 successful missions for the v1.1 between the launch of Canada's CASSIOPE scientific satellite in September 2013 and the CRS-5 Dragon cargo flight in April 2015. During those 19 months, SpaceX delivered its first half-dozen payloads into GTO, together with one satellite into polar orbit, four ISS-bound Dragons into low-Earth orbit and also accomplished its maiden foray to the L1 Lagrange Point, some 930,000 miles (1.5 million km) beyond Earth. Equipped with nine Merlin 1D engines on its first stage, the v1.1 offered a 200,000-pound (90,700 kg) increased propulsive yield over the 1.1-million-pound (503,000 kg) first-stage output of the Merlin 1C engines of its predecessor, the v1.0. Fueled by a mixture of liquid oxygen and a highly refined form of rocket-grade kerosene, known as "RP-1", the Merlin 1D was extensively tested during the summer of 2012 and its 1.3-million-pound (590,000 kg) first-stage thrust significantly raised the bar for SpaceX, by enabling a 27-percent payload hike to low-Earth orbit and a somewhat smaller increase to GTO.
Also factored into the v1.1 and subsequent v1.2 designs was the much-publicized capability to soft-land its first-stage hardware on the deck of the Autonomous Spaceport Drone Ship (ASDS) in the Atlantic Ocean, as part of SpaceX's ongoing effort to eventually confer reusability on its vehicles. This capability was afforded by three engine firings towards the end of first-stage flight: an initial "Boost-Back" to adjust its impact point, push it "upward" and redirect it towards its launch site, followed by a decelerating "Supersonic Retro-Propulsion" maneuver and finally a "Landing" burn to alight on the ASDS at a smooth 4.5 mph (7.2 km/h). In support of this goal, a series of "controlled oceanic touchdowns" in April, July and September 2014 were followed with mixed fortune earlier this year, when two attempts were made to land on the ASDS. The first reached the deck, but impacted hard at a 45-degree angle and exploded, whilst the second landed with excessive lateral velocity and toppled over upon impact.
By this point, and even with only a relatively small number of v1.1 vehicles actually having flown, the effort to bring an enhanced Falcon—variously described as the "v1.2" or the "Full Thrust" (FT)—to operational status steadily gained momentum. It is understood that the v1.1 utilized the Merlin 1D engine at 80 percent of its rated capability, with 20 percent held in reserve, in order to afford maximum flexibility for the payload to achieve its correct orbital location. In contrast, the v1.2/FT centers around an upgraded "Merlin 1D+" engine, which reportedly generates 1.53 million pounds (694,000 kg) of thrust at liftoff, effectively operating at "full" (100-percent) capacity. This will increase to around 1.7 million pounds (771,100 kg) as the vehicle travels higher into the rarefied upper atmosphere. Similarly, the Merlin 1D Vacuum engine of the second stage will see a corresponding increase in propulsive yield from 180,000 pounds (81,600 kg) in the v1.1 to 210,000 pounds (95,250 kg) in the v1.2/FT. According to a source close to SpaceX, "FT" is the internal code name for calculating the Merlin 1D's output at 100-percent, adding that "this improves the Falcon 9's performance by 20 percent, although this "improvement" was not really new: it was always there, but never utilized". At the time of the CRS-7 failure, it is understood that SpaceX intended to stage its first v1.2/FT launch in July 2015, delivering SES-9 to GTO.
However, the 20-percent performance hike achieved by throttling the engines from their 80-percent to 100-percent power levels has been expanded yet further to reach an overall 33-percent "performance gain" over the v1.1. This gain has been met in part through structural enhancements to the vehicle's airframe, including a 10-percent increase in propellant tank volumes, a lengthened second stage with extended Merlin 1D Vacuum engine, upgraded landing legs and grid fins, an improved "Octaweb" support structure for the first-stage engine suite, a strengthened "interstage" between the two stages and a central "pusher" to ensure a smooth stage-separation process. All told, these enhancements increase the height of the v1.2/FT vehicle to 229.6 feet (70 meters), about 5.6 feet (1.6 meters) taller than the v1.1.

The Merlin-1D burns hot and hard at SpaceX's Rocket Development Facility in McGregor, Texas. An uprated version of the engine, known as the "Merlin 1D+", will fly on the Return to Flight (RTF) mission, perhaps as soon as mid-November. Photo Credit: SpaceX
 
Additionally, the 33-percent performance gain has been met through "super-cooling" the liquid oxygen load—in what Musk described as "deep cryo oxygen"—below its normal saturation condition, in order to increase its density and permit the carriage of a larger load of propellants in the Falcon 9's tanks. "Propellant densification," noted engineers Ke Nguyen and Timothy Knowles in an American Institute for Aeronautics and Astronautics (AIAA) paper, "is one of the key technologies needed to meet the challenges of future reusable launch vehicles." The densification process, AmericaSpace understands, has required the installation of specialized cooling stations at SpaceX's dedicated Falcon 9 pads of Space Launch Complex (SLC)-40 at Cape Canaveral Air Force Station, Fla., and Space Launch Complex (SLC)-4E at Vandenberg Air Force Base, Calif.
The additional performance gained from the structural modifications and the liquid oxygen densification is expected to be of assistance to SpaceX at it aims to deliver larger and heavier communications satellites to GTO and seeks lucrative Department of Defense contracts for major classified payloads. However, this stance has caused a measure of consternation and serious doubts have been raised over the frequency of major enhancements to SpaceX's vehicles in a relatively short span of time. "The launch industry tends to be very conservative," a Parabolic Arc article highlighted last July. "Changes are made very carefully and only after thorough testing. Experience has shown that while upgrades can improve a rocket's performance, they can also cause problems." The article quoted Gen. William Shelton, former commander of Air Force Space Command, who expressed concern that the upcoming v1.2/FT—which is believed to be the vehicle that SpaceX will use to bid for Department of Defense contracts—has yet to complete a single mission, much less pass through a full certification process. "In other words, the Air Force will be launching on yet another version of the Falcon 9, with an even shorter launch history than the one that just failed," Parabolic Arc noted. "That can be handled with some additional certification work. However, it's an unnerving prospect for an organization whose primary focus is on mission assurance, not cost."
Notwithstanding these concerns, Musk expects that the v1.2/FT improvements will allow SpaceX to soft-land its first-stage hardware on the ASDS, even during high-energy launches to the 22,300-mile (35,900 km) altitude of GTO. Previously, only comparatively low-energy launches to Low-Earth Orbit (LEO) had seen soft-landing attempts, although SpaceX originally intended to bring the first stage from NASA's L1-bound Deep Space Climate Observatory (DSCOVR) back to the ASDS in February 2015, but was ultimately thwarted by rough seas. "It's always a trade-off between height and payload weight when the capacity is fixed," AmericaSpace was told by a source close to SpaceX. "The higher the orbit, the less weight could get up there, with any given thrust capacity. LEO is relatively close, compared to GTO, so SpaceX was able to save some of the liquid oxygen for the landing attempts. With GTO, they needed to launch as high as possible and did not want to risk trying to save liquid oxygen for the landing attempts, as that could jeopardize their ability to get a client's satellite as high as it needed to get."
The weeks ahead are expected to see significant progress as SpaceX readies for an upcoming salvo of launches. The original CRS contract with NASA, signed back in December 2008, calls for 12 dedicated ISS cargo missions, of which six have been satisfactorily completed, and major payloads destined to fly aboard future Dragons include the Bigelow Expandable Activity Module (BEAM) and the second International Docking Adapter (IDA-2). There also exists a backlog of commercial payloads—including 11 Orbcomm OG-2 satellites—and NASA's Jason-3 ocean surface topography mission, with the latter expected to ride an old-style v1.1, due to its LEO destination.
 

 VIDEO: First static fire of the upgraded Falcon 9's first stage

[Salo]

http://arc.aiaa.org/doi/abs/10.2514/6.2002-4293

[vlad7308]

Сало, скажите пожалуйста, в какой-либо регулярно летающей РН сейчас используется переохлаждение крио-компонентов топлива?

[Grus]

vlad7308 пишет:
переохлаждение крио-компонентов топлива

http://www.buran.ru/htm/12-3.htm

[Apollo13]

vlad7308 пишет:
Сало, скажите пожалуйста, в какой-либо регулярно летающей РН сейчас используется переохлаждение крио-компонентов топлива?

Я не Сало, но на выставке мне сказали что в Антаресе на НК-33 использовался переохлажденный кислород, а на РД-181 нет. Наверно еще на Союз-2.1в переохлажденный используется.

[Salo]

Там скорее вынужденное использование, поскольку НК-33 не рассчитан на использование кипящего ЖК.
ЕМНИП переохлаждают на пять градусов.

[vlad7308]

В общем, похоже что нигде реальное переохлаждение сейчас не используется.
Оно и понятно, геморрой тот еще.

Мне кажется, зря Маск это затеял.
Нарушает собственные базовые принципы - "просто, дешево, эффективно".

[Старый]

vlad7308 пишет:
В общем, похоже что нигде реальное переохлаждение сейчас не используется.

В блоках ДМ. 

Оно и понятно, геморрой тот еще.
Мне кажется, зря Маск это затеял. 
Нарушает собственные базовые принципы - "просто, дешево, эффективно".

Как оказалось всё достаточно просто. Из герметичной ёмкости с жидким кислородом откачивается газообразный кислород. Давление падает, кислород вскипает при этом охлаждаясь за счёт теплоты фазового перехода. При заданной температуре процесс прекращается. Откачаный кислород можно снова сжижать а можно и выбрасывать в атмосферу. Надо посмотреть теплоёмкость жидкого кислорода и теплоту парообразования чтобы узнать какая часть кислорода при этом будет потеряна. 

[vlad7308]

Нужна еще постоянная рециркуляция в заправленной РН

[Петр Зайцев]

Как оказалось всё достаточно просто. Из герметичной ёмкости с жидким кислородом откачивается газообразный кислород. Давление падает, кислород вскипает при этом охлаждаясь за счёт теплоты фазового перехода.

Элон пошёл по другому пути - прогоняет через теплообменник с жидким азотом. Заданная температура - на 1К выше тройной точки.

[Буцетам]

Петр Зайцев пишет:

Как оказалось всё достаточно просто. Из герметичной ёмкости с жидким кислородом откачивается газообразный кислород. Давление падает, кислород вскипает при этом охлаждаясь за счёт теплоты фазового перехода.

Элон пошёл по другому пути - прогоняет через теплообменник с жидким азотом. Заданная температура - на 1К выше тройной точки.

"Заданная температура" чего? Азота? Ну тогда температура кислорода будет градуса на 2 повыше. Итого: 66 Кельвин. Переохлаждение на 24 Кельвина относительно обычного жидкого кислорода. Это не самый продвинутый путь! Самый простой - да. В общем, в духе SpaceX    

Мне известны четыре способа:
1) Тот, который выбрали инженеры Маска (теплообменник с жидким азотом, температура около 66 К, вакуумный насос не нужен, достаточно простого эжектора)
2) Откачка паров жидкого кислорода вакуумным насосом (минимальная температура около 55 К, но для этого нужен офигенский    вакуумный насос, поэтому никто 55 К и не делал никогда)
3) Использование теплообменника в котором вместо азота смесь O2+N2 (эвтектическая смесь замерзает при 50 К). Не сильно лучше второго способа (нужен настоящий вакуумный насос), но может быть проще в технологическом плане, потому что при той же температуре, вакуум можно держать не такой высокий (т.е. давление паров - выше).
4) Барботирование (пробулькивание) через жидкий кислород какого-нибудь (вариантов всего два: гелий и неон) газа. не уверен, насколько это эффективно, но предлагался для термостатирования заправленной ракеты на старте.

Наши использовали третий вариант для переохлаждения кислорода (Энергия-Буран). Температура была 57 К. Примерно на 10 градусов ниже чем у Маска.
Upd. Немного исправил

[Salo]

http://spacenews.com/spacex-wrapping-up-falcon-9-failure-investigation/

SpaceX Wrapping Up Falcon 9 Failure Investigation
by Jeff Foust — October 9, 2015

Josh Brost of SpaceX said early reports on the cause of the June 28 Falcon 9 failure — that a strut holding down a helium bottle inside a propellant tank in the rocket's upper stage broke — "have born out." Credit: NASA TV  
 
LAS CRUCES, N.M. — SpaceX expects to complete its final report on the June 28 failure of its Falcon 9 launch vehicle within a month, but does not yet have a firm timetable for resuming flights, a company official said Oct. 8.
Josh Brost, a business development executive with SpaceX, said at the International Symposium for Personal and Commercial Spaceflight here that the final report on the failure should be delivered to the Federal Aviation Administration, which licensed the launch, "maybe in the next month."
On that launch, of a Dragon cargo spacecraft bound for the International Space Station, the vehicle broke apart less than two-and-a-half minutes after liftoff. In a July 20 briefing, SpaceX Chief Executive Elon Musk said a strut holding down a helium bottle inside a propellant tank in the rocket's upper stage broke. That caused the tank to overpressurize and burst, destroying the vehicle.
That explanation has held up during later phases of the investigation, Brost said. "The early reports you saw in the press, where we talked about it being caused by a strut, those have born out," he said.
The company has not offered a specific timetable for resuming Falcon 9 launches. "We're hoping to return to flight in the next couple of months," he said. That launch is expected to also be the first flight of an upgraded version of the rocket with increased thrust from its nine first-stage engines.
Once the Falcon 9 does return to flight, Brost said, the company will ramp up launch activities quickly. "We'll start launching at a fairly high cadence next year," he said.

[Apollo13]

https://twitter.com/pbdes/status/653826486655414272

SpaceX VP Rosen: Current assessment is a return to flight w/ in 6-8 weeks.#IAC2015

Потихоньку движемся к декабрю.

[azeast]

Apollo13 пишет:
Потихоньку движемся к декабрю

Частная американская компания-производитель космических ракет SpaceX сообщила, что в начале декабря планирует вернуть к эксплуатации модернизированную ракету Falcon 9, передает агентство Рейтер со ссылкой на заявление вице-президента компании.
Ракета Falcon 9 потерпела крушение на третьей минуте полета 28 июня. По предварительным данным, причиной катастрофы могла стать поломка стойки в топливной системе первой ступени ракеты.
"Мы полагаем, что в течение последующих шести-восьми недель мы сможем вернуться к полетам", — заявил во вторник вице-президент компании Ли Розен на Международном астронавтическом конгрессе, который проходит в Иерусалиме.


РИА Новости http://ria.ru/world/20151013/1301285004.html#ixzz3oT9c1QDq

[triage]

А подскажите где стойка сломалась в первой или во второй, на 515 странице тоже задавались вопросом.

[Apollo13]

pnetmon пишет:
А подскажите где стойка сломалась в первой или во второй, на 515 странице тоже задавались вопросом.

Во второй ступени конечно.

[Salo]

https://twitter.com/pbdes/status/656756468876750848

Peter B. de Selding ‏@pbdes  
Arianespace CEO on SpaceX reusability: Our initial assessment is need 30 launches/yr to make reusability pay. We wont have that.

  1:58 - 21 окт. 2015 г.