Новости программы Constellation

[Дэйв Боуман]

ИМХО это все неофициальные проекты. Планирование марсианских экспедиций намечается начать с 2020 года.

как бы то сказать - НАСА обнародовало этот проект. Т.е. в некоторой степени его можно считать "официальным"

[Александр Хороших]

ИМХО это все неофициальные проекты. Планирование марсианских экспедиций намечается начать с 2020 года.

как бы то сказать - НАСА обнародовало этот проект. Т.е. в некоторой степени его можно считать "официальным"

Марс-проект - это е по теме, ну да ладно. Mars reference Mission 5.0 базируется на предыдущей версии, 4. А там ЯРД. А так это просто оценки, сделанные либо для НАСА какой-либо компаней, либо в НАСА. Так что проектом ещё не пахнет.

[Дэйв Боуман]

ИМХО это все неофициальные проекты. Планирование марсианских экспедиций намечается начать с 2020 года.

как бы то сказать - НАСА обнародовало этот проект. Т.е. в некоторой степени его можно считать "официальным"

Марс-проект - это е по теме, ну да ладно. Mars reference Mission 5.0 базируется на предыдущей версии, 4. А там ЯРД. А так это просто оценки, сделанные либо для НАСА какой-либо компаней, либо в НАСА. Так что проектом ещё не пахнет.

можна ссылочку. Хочу глянуть что это.

[Александр Хороших]

Поправка: в 3-й версии говорят о ЯРД:

The TMI stage (used to propel the spacecraft from LEO onto a trans-Mars trajectory) employs nuclear thermal propulsion. Nuclear thermal propulsion was adopted for the TMI burn because of its performance advantages; its advanced, previously demonstrated state of technology development; its operational flexibility; and its inherent mission enhancements. A single TMI stage was developed for both piloted and cargo missions. The stage is designed for the more energetically demanding 2009 fast transit trajectory and then used in the minimum energy cargo missions to carry the maximum payload possible to Mars. In the human missions, the TMI stage uses four 15,000 lb. thrust NERVA (Nuclear Engine for Rocket Vehicle Application)-derivative reactor (NDR) engines (Isp = 900 seconds) to deliver the crew and the surface habitat/descent stage onto the trans-Mars trajectory (Borowski, et al., 1993). After completion of the two-perigee-burn Earth departure, the TMI stage is inserted into a trajectory that will not reencounter Earth or Mars over the course of one million years. The TMI stage used with the crew incorporates a shadow shield between the NDR engine assembly and the LH2 tank to protect the crew from radiation that builds up in the engines during the TMI burns. Although it may seem wasteful to discard the nuclear stage after one use, the complexity of Mars orbit insertion and rendezvous operations for the return flight are avoided.

http://cmex.ihmc.us/CMEX/data/FrontPg/Missions/human_missions/links/Human_Mars_Mission3.html#3.3.5

[Александр Хороших]

Прошёл успешный тст разделния ступеней ракеты Ares-I: http://www.nasa.gov/mission_pages/constellation/ares/flighttests/aresIx/skirt_test.html

[Pova]

тут ссылки на многие проекты, Mars reference Mission 5.0 в том числе:
http://en.wikipedia.org/wiki/Manned_mission_to_Mars#NASA_Design_Reference_Mission_5.0_.282007.29

форум:
http://www.newmars.com/forums/viewtopic.php?t=5616

[Александр Хороших]

A technology development engine that may help NASA safely return astronauts to the lunar surface has successfully completed its third round of testing. The goal of these tests is to reduce risk and advance technology for a reliable and robust rocket engine that could enable America's next moon landing.

The tests by Pratt & Whitney Rocketdyne in West Palm Beach, Fla., helped to gather data on this concept engine that might play a role in the next stage of human exploration of the moon. Most rockets make spacecraft travel faster. The goal of a lunar lander descent engine is to slow the vehicle so astronauts can land safely.

The Common Extensible Cryogenic Engine, or CECE, is a deep-throttling engine, which means it has the flexibility to reduce thrust from 100 percent down to 10 percent -- allowing a spacecraft to gently land on the lunar surface. The 13,800-pound thrust engine uses extremely cold liquid oxygen and liquid hydrogen as propellants.

During the test, the engine was successfully throttled from a high of 104 percent of the engine's potential down to eight percent, a record for an engine of this type. A cryogenic engine is needed to provide high performance and put more payload on the surface of the moon. The CECE demonstrator has evaluated two engine configurations during three rounds of hot-fire testing.

"The first test series in 2006 was a challenge but showed promise," said Tony Kim, Deep Throttling Engine project manager at NASA's Marshall Space Flight Center, Huntsville, Ala. "Testing in 2007 provided an in-depth examination of low-power-level throttling and engine performance characteristics. This third cycle we actively addressed and found solutions to the challenges we faced."

The team carefully assessed test results that showed pressure oscillations in the engine at lower throttle levels called "chugging." Chugging may not be a concern for the engine itself, but the resulting vibrations could have the potential to resonate with the structure of the rocket and cause problems for the lander or crew.

Injector and propellant feed system modifications successfully eliminated engine chugging by controlling liquid hydrogen and liquid oxygen flow to the combustion chamber. The latest engine configuration incorporates a new injector design and propellant feed system that carefully manages the pressure, temperature and flow of propellants.

"The technology developed from this effort will help engineers successfully design future cryogenic engines to meet the throttling requirements of the Constellation Program's Altair lunar lander," Kim said.

The CECE is based on the existing Pratt & Whitney Rocketdyne RL10 upper stage rocket engine. Previous first-hand flight experience, as well as this data, will allow engineers to develop simulation models that can focus testing for efficiency and effectiveness.

The CECE collaboration includes engineers from Marshall, NASA's Glenn Research Center in Cleveland, and Pratt & Whitney Rocketdyne. NASA has invested in CECE technology since 2005 as part of the Propulsion and Cryogenics Advanced Development project at Glenn. The project is funded by the Exploration Technology Development Program in NASA's Exploration Systems Mission Directorate.
Видео: http://anon.nasa-global.edgesuite.net/anon.nasa-global/MARSHALL/CECE_Engine.asx

[Александр Хороших]

Продолжается возведение башен защиты отмолний на старте ля Ареса-1: http://www.nasa.gov/multimedia/imagegallery/image_feature_1275.html

[Karen]

C-300, Я полностью понимаю вашу цитату о тестировании двигателя для лунной посадке. Проблема в том что она на английском. Не забывайте давать короткий обзор по-русски. Тем временем, для тех не знающие английский - есть интернет-переводчики. В гугле есть новый формат с оригиналом и переводом бок а бок: translate.google.com. Полезно когда перевод прийдет немного смешным.

[mmm]

Полезно когда перевод прийдет немного смешным.

Это вряд ли. Что хорошо для клоуна, не всегда хорошо в науке.

[Sleepwalker]

Полезно когда перевод прийдет немного смешным.

Это вряд ли. Что хорошо для клоуна, не всегда хорошо в науке.

"когда" меняем на "в случае, если" и понимаем пост заново.

[Karen]

Несмотря на того, что "в случае, если" возможно лучший русский, я использовала "когда" потому, что всегда становится смешным. Тем не менее, сравнение обеих бок а бок, иногда помогает...ну немного...ну чуточка(?)

Самое главное - напишите по-русски. Если я могу это сделать, русские несомненно могут.
Конец офф-топика.

[Александр Хороших]

На космодром Кеннеди прибыл симулятор модуля экипажа с системой САС: http://anon.nasa-global.edgesuite.net/anon.nasa-global/ksc/ksc_020609_ares_1-x.asx

[Алексей Шевченко]

        Да, замечательное видео и хорошая новость.

[Александр Хороших]

To provide additional thrust for the Ares I rocket, NASA engineers have designed a new 12-fin forward casting core. The 12-fin core is created by pouring propellant into an insulated and lined segment containing grain core tooling. The propellant mold is then inserted in to the solid rocket motor (SRM) casing. This creates open space in the center of the solid rocket which allows surface area for the propellant to burn.
http://www.nasa.gov/mission_pages/constellation/multimedia/12mold_1.html
Инженеры НАСА разработали новый, 12 лучевой сегмент для твердотопливной первой ступени ракет Ares I.

[Александр Хороших]

Рассказ о системе разделения первой и второй ступеней Ares I: возможные риски, моторы разделения, отработка моделей и т. п.

While staging is a necessary part of the launch process, it does have potential risks and is given additional scrutiny because of the relative complexity. As with all launch events, staging is studied carefully by project engineers to ensure mission success. This is a normal part of the NASA development process.  For Ares, NASA has evaluated the first-stage-to-upper-stage-separation event from the perspective of ensuring the ability to separate, being able to confirm separation has occurred, and having sufficient clearance to not re-contact the J-2X engine nozzle with the interstage as it is pulled away from the Ares I upper stage. 

The separation of the Ares I stages is carefully timed and based upon preset acceleration levels. Separation will occur when those levels are read by on-board accelerometers, which takes place when the first stage runs out of propellant and the internal pressure reduces. A set of linear shaped charges between the upper stage and first stage will fire, separating the metal between the first stage and the interstage. At the same time, ten booster deceleration motors fire to pull the first stage directly backward, while eight ullage settling motors fire to push the upper stage forward. After the segments separate, the first stage tumble motors fire to slow the stage for its return trip to Earth and eventual recovery.

As part of this process, NASA engineers ran thousands of physics-based models (“Monte Carlo” analyses) to evaluate the first stage/upper stage separation. These models are developing and continue to improve. In addition, engineers analyzed and evaluated the system redundancies and potential for re-contact between the J-2X nozzle and the interstage. NASA’s analyses concluded that there will be a good separation, even in a worst case scenario. Because this is a critical event, NASA had the Aerospace Corporation perform an independent analysis and their conclusions supported the NASA analysis.

This along with many other developments is a key “risk” that will continue to be watched closely, and managed and mitigated using proven risk management techniques as we proceed with the final design phase of Ares I.

http://blogs.nasa.gov/cm/blog/Constellation/

[Александр Хороших]

Подготовка к испытаниям exhaust nozzles (выхлопной патрубок ТНА, я правильно перевожу?) двигателя J-2X.

This image shows the rocket engine exhaust nozzles, which are being designed and tested at NASA's Marshall Space Flight Center. Engineers at the center are testing the nozzle to ensure that it is strong enough to withstand uneven forces. Testing at Marshall's Nozzle Test Facility enables Pratt & Whitney Rocketdyne design engineers to apply test data to the computer analyses used to design the nozzle.

[kabelman]

"Это изображение показывает сопло выхлопа ракетного двигателя, которые разрабатываются и проверяются в Центре космических полетов имени Маршалла НАСА. Инженеры в центре проверяют сопло, чтобы гарантировать, что это достаточно сильно, чтобы противостоять неравным силам. Тестирование в Испытательном Средстве Сопла Маршалла позволяет инженерам проекта Pratt & Whitney Rocketdyne обратиться, данные испытаний к компьютерным исследованиям имели обыкновение проектировать сопло."   Вот машинный перевод текста под выше показанной фото.

[Александр Хороших]

Понемногу начинаюти над Аресом-5 работать:

The Boeing Company [NYSE: BA] today announced that its Space Exploration division has submitted proposals to NASA for the Ares V Phase 1 Design Support Contracts.

Boeing submitted proposals for design support of the Ares V cargo launch vehicle's payload shroud, which will protect the Altair lunar lander during launch; the Earth-departure stage; the core stage, a liquid-fueled central booster element; and avionics and software. The work includes assessing requirements, risks and opportunities; performing trade studies and analysis; and producing final reports.

www.boeing.com

[anovikov]

Ну судя по тексту это именно сопло РД, а не выхлопной патрубок ТНА. Но какой-то странный.