USAF Plans For Reusable Booster Development

[Agent]

http://www.aviationweek.com/aw/generic/story.jsp?id=news/awst/2010/04/19/AW_04_19_2010_p30-219818.xml&headline=USAF%20Plans%20For%20Reusable%20Booster%20Development&channel=defense

Plans to begin technology development for a reusable booster system to replace its existing expendable launch vehicles beyond 2025 are being finalized by the U.S. Air Force.

With the Air Force facing escalating costs on the Evolved Expendable Launch Vehicle (EELV) program, the new system offers the promise of cutting launch costs more than 50% by combining a reusable first stage with expendable upper stages. The booster would take off vertically and return to a runway landing at the launch site.
...
The plan calls for replacing the Atlas V and Delta IV with two versions of the RBS: a single reusable first stage and expendable cryogenic upper stage for medium-lift missions; and two reusable boosters, cryogenic core stage and upper stage for heavy-lift and growth missions. Initial operational capability is set for 2025

[Космос-3794]

ВВС планируют разработку многоразовой модульной системы для замены существующих носителей (EELV) к 2025. .
Старт вертикальный с возвратом ускорителей на посадочную полосу космодрома.
План проходит окончательные стадии определения архитектуры многоразовой системы внутри ВВС. Предполагаются два варианта Reusable Booster System (RBS):
 - носитель средней грузоподъемности - один многоразовый ускоритель и верхняя (одноразовая) криогенная ступень.
 - тяжелый носитель - два многоразовых ускорителя, криогенные центральная  и верхняя ступени.
Начало пусков планируется к 2025, с полной заменой EELV в 2030. Ожидаемое снижение стоимости 50% (по сравнению с сегодняшней ценой EELV) при частоте 8 пусков в год. Рассчеты основаны на ресурсе ускорителя в 100 полетов и ресурсе двигателей в 10 полетов.
В 2013 предполагается испытать маломасштабный демонстратор возвращаемой первой ступени. Для возврата на посадочную полосу будут задейстоваться ЖРД первой ступени.
В 2016-2017 последуют полеты среднеразмерного демонстратора RBX.
Использование ЖРД было выбрано после многочисленных исследований альтернативных вариантов - планирующей, и с использованием ВРД. Это позволяет производить разделение ступеней при больших скоростях чем при планирующей схеме, и соответственно уменьшить вторую ступень. А также уменьшает расстояние (до ПП, видимо) и скорость входа после разделения по сравнению с ВРД-схемой, что снижает требования к термозащите.
Аэродинамические нагрузки при 180-градусных пируэтах не могут быть точно смоделированы в аэродинамических трубах, поэтому планируется выделить ок 30 млн долл на строительство 15-футового исследовательского демонстратора воздушного или наземного базирования.
Последующий RBX, длиной 50-60 футов, будет представлять полностью функциональную уменьшенную модель многоразового ускорителя. Оба демонстратора будут использовать существующие двигатели. Параллельно будет вестись разработка мощного кислород-керосинного ЖРД. Ведутся переговоры с NASA о совместной разработки в рамках общего бюджета, т.к. "боливар не выдержит двоих".

[sychbird]

Хорошая новость для Байкала. У него появляется перспектива на включение в среднесрочную программу финансирования.

[Петр Зайцев]

В теме про МРКС было немного обсуждения, цитат, и пара фоток
http://www.novosti-kosmonavtiki.ru/phpBB2/viewtopic.php?p=572459#572459
http://www.novosti-kosmonavtiki.ru/phpBB2/viewtopic.php?p=573427#573427
http://www.novosti-kosmonavtiki.ru/phpBB2/viewtopic.php?p=578463#578463

[Salo]

Yet another episode in America's RLV soap opera

by Taylor Dinerman
Monday, April 26, 2010

According to a recent report in Aviation Week and Space Technology, the Air Force has discovered that without NASA's support, the cost of the Evolved Expendable Launch Vehicle (EELV) program is going to radically increase. Even if the Air Force can convince NASA as well as a few commercial customers to buy more Delta 4 and Atlas 5 vehicles, paying for the infrastructure and the rest of the overhead for these rockets is going to put serious pressure on the USAF's space budget for the foreseeable future. So once again they are turning to the best and most logical answer to the long-term launch cost dilemma: reusable launch vehicles (RLVs).
The scale and cost of building a fully operational RLV system will require a national commitment similar to the Saturn 5 or the Shuttle.

The Defense Department has been here before. Even if we leave aside the question of why the Space Shuttle was designed the way it was, the US military has had an intermittent, inconsistent, and inadequately funded interest in this technology going back at least to the DC-X program of the early 1990s. The sad saga of the X-33, which was supposed to lead to a shuttle replacement, should be a cautionary tale for all involved.

In spite of a few promising new technological advances, the scale and cost of building a fully operational RLV system will require a national commitment similar to the Saturn 5 or the Shuttle. Even worse, the new system will have to start from almost nothing, since, unlike the NASA Constellation program, it will not be able to build on any pre-existing hardware.

Another problem is that the Air Force wants the new system to fly its first missions in 2025. Even assuming that they can meet such a schedule, the chances that the program could survive the scrutiny of two or three new administrations and at least six new Congresses seem minimal. If the early development funding is inadequate, then the future costs will inevitable overrun the original estimates. If, on the other hand, the Pentagon asks Congress for enough money up front to ensure that the design and development is done on a solid basis, they risk sticker shock.

Yet there is no question that the nation needs a strong RLV program if it is to maintain its global leadership role in space. If, by the middle of the next decade, the US does have an operational heavy-lift launcher—either the Ares 5 or something alternative—and a medium- and medium-heavy-class RLV, it will regain the unquestioned position of space superiority that seems now to be slipping away. However, the sad fact is that too many RLV programs in the past have failed due to a lack of sustained political support.

According to the report in Aviation Week, the proposed Reusable Booster System (RBS) has all the hallmarks of a classic RLV program. It hopes to begin with a small demonstrator that will fly around 2013, followed by a larger scale model in 2016–2017. This kind of step-by-step approach is an excellent idea; if adequately funded and managed by skilled professionals it should succeed. The sad fact is that both funds and competent manpower are in short supply, so the Air Force would have give this program a high priority in order to see it through to completion.
The Air Force's B-29 bomber secured US dominance of the post-World War Two commercial aviation industry; the RBS could do the same for space access.

NASA has already begun talks with the Air Force on cooperation on the new heavy-lift rocket liquid oxygen/hydrocarbon engine, the article noted. This kind of partnership seems logical, but the record of USAF/NASA cooperation on RLV programs such as the DC-X and the X-33 has been less than stellar. It may be wise for the two organizations to keep an arms' length relationship on this program. After all, if the RBS comes to depend on NASA's new engine and that program is cancelled—like so many other NASA programs have been—it would leave the military with the unfortunate choice of fully funding a new rocket engine program or canceling their program and keeping the EELVs in operation until 2040 or even longer.

If the Air Force can build the RBS, and if it operates with anything resembling the efficiency and cost effectiveness that they hope to achieve, the it will be the core element in US spacelift technology for the next fifty years. The Air Force's B-29 bomber secured US dominance of the post-World War Two commercial aviation industry; the RBS could do the same for space access. This will only be possible if the Defense Department has the courage and the vision to fully fund the program right from the start.

The RBS could be used as the first stage of a variety of space vehicles, both manned and unmanned. It could, for example, carry a large winged "space taxi" type of spaceplane to service both a future government space station or a private manned space facility or space hotel, depending on the circumstances. It could also be used to economically launch large structures into orbit such as those needed for a large space solar power satellite or a space factory.

Without a national commitment to a program that will radically lower the costs of access to orbit, none of the promises being made by NASA or by the Air Force can be met, certainly not in the long term. If the Air Force follows NASA down the path towards an unfocused hodgepodge of small technology development programs, it will be putting the powerful US array of space assets in long-term jeopardy.

Taylor Dinerman is an author and journalist based in New York City.

[Петр Зайцев]

Кларк Линдсей уже возмущался по поводу писанины Диннермана

http://www.hobbyspace.com/nucleus/index.php?itemid=20243

Taylor Dinerman discusses the US Air Force plan to start a fly back reusable booster project: Yet another episode in America's RLV soap opera. He starts by exaggerating the effect of changes at NASA on the costs of EELVs. Even the AvWeek article says that EELV escalating costs are only "in part" due to NASA and even that is extremely debatable. A commercial crew transport with an EELV will increase its flight rate, which will drive costs down if this is done with minimal changes to the basic EELV system.

His claim that "the scale and cost of building a fully operational RLV system will require a national commitment similar to the Saturn 5 or the Shuttle" is highly debatable as well. Institutionally, DOD and NASA are certainly biased towards this approach but it will mostly like lead to the same result as the Saturn 5 and Shuttle - an extremely expensive system that does not provide affordable and sustainable spaceflight. There are multiple challenges to developing a fully reusable space transport and any one initial grand design is unlikely to overcome all of them. A better approach is to pursue multiple low cost vehicles with different designs and learn what works and what doesn't work in real life operation.

"Even worse, the new system will have to start from almost nothing, since, unlike the NASA Constellation program, it will not be able to build on any pre-existing hardware." Building on extremely expensive existing hardware provides no benefit if the goal is low cost space access. An alternative is to work with the commercial companies that are pursuing low cost reusable hardware. For example, NASA's COTS/CRS program is doing this now with SpaceX, which is serious about reusing the Falcon 9 boosters and Dragon capsule. Most all of the suborbital space vehicle companies, i.e. Scaled, XCOR, Blue Origin, etc., have orbital designs that they are pursuing on the side. The firms will have fully reusable fly-back-refuel-re-fly systems in regular operation soon and the knowledge gained will be applied to the design of the first stage vehicles in their orbital systems. DOD/NASA could certainly work with these companies to take advantage of that existing hardware and operational experience.

Ржу нимагу

[SpaceR]

Вот анонс первой серии ещё одного сезона мыльной оперы "Американский RLV":

http://news.discovery.com/space/air-force-reusable-rockets.html
AIR FORCE WANTS ITS ROCKETS BACK
A new prototype rocket could give the Air Force a round-trip ticket to space by 2013.



The Air Force estimates a reusable, fly-back booster could cut launch costs by 50 percent.
Starcraft Boosters

THE GIST
- The Air Force is looking to develop a prototype reusable rocket that could fly itself back to the launch site.
 - Military satellites now ride into space on one-time-use expendable rockets.
 - A prototype is intended to test turn-around maneuvers and could fly in 2013.

The U.S. Air Force has a vision of the future that includes rockets that are not only reusable, but also able to fly back to Earth and land autonomously on a runway.

Currently, most military satellites are launched on one-time-use rockets, such as the Atlas 5 and Delta 4 vehicles. The best-known reusable boosters are flown on the space shuttles, but recycling them is no easy task. The solid-fuel rockets, which are jettisoned two minutes after liftoff, parachute down into the ocean where they are retrieved by ship. Getting them ready to fly again is labor-intensive and expensive.

Hoping to spark some technological innovation, the Air Force Research Laboratory is rolling out a $33-million pathfinder program to develop a prototype booster that can glide or fly itself back to the launch site. The first step of the program likely would be aimed at demonstrating a turn-around maneuver known as "rocket-back," whereby a rocket would use its own engines to fly back to the launch site and glide in for landing.

The first test flights are targeted for 2013.

NASA studied fly-back boosters more than a decade ago as part of a potential suite of upgrades to the space shuttles, but never pursued its development.

At least two companies hold patents for fly-back boosters: Lockheed Martin, which in 2008 quietly tested a sub-scale reusable fly-back rocket prototype and a firm known as Starcraft Boosters, founded by Apollo 11 astronaut Buzz Aldrin to develop low-cost alternative launchers.

While details of Lockheed's 2008 test flight were not released, another group did successfully test a sub-scale fly-back booster based on Aldrin's design.

"Our two big areas of concern were the separation of the vehicle so that it would come off the center stage in a way that wouldn't damage or impede the flight, and how to control it on the way down," Trevor Foster, project manager for the 2001-02 test program, told Discovery News.

Foster's team at California Polytechnic State University in San Luis Obispo, Calif., flew a single-stage reusable launch vehicle three times -- once successfully -- and a two-stage vehicle once. "That one went really well," Foster said.

The vehicle was about 10 feet tall, with a six-foot wingspan.

"It seems to me that the only show-stopper would be something along the lines of what they're seeing with the space shuttle. Is it really reusable, or do they have to rebuild it every time?" Foster said. "As far as the technology itself, it didn't seem to be a show-stopper there."

The Air Force estimates a reusable, fly-back booster could cut launch costs by 50 percent. For the pilot project, officials envision a sub-scale vehicle, at least 15 feet long, that would be launched on a sounding rocket or off of an aircraft for three test flights to demonstrate different rocket-back maneuvers.

The Air Force expects to award up to three $1.5-million contracts for studies then select one team for a $28.5-million contract to build the prototype. An industry briefing on the project met last week.

Как видно, попил на НИР продолжает оставаться весьма популярным: 33 зелёных лимона уже на кону.

[KBOB]

На какой высоте/скорости/удаленности от места старта планируется расстыковка 1-й и 2-й ступеней?