ARCASPACE

Infobox_Company
company_name = ARCA
company_
company_type = Private
foundation = 1999
location = Romania, RO
industry = Aerospace and space tourism
homepage = [http://www.arcaspace.ro www.arcaspace.ro]

Asociaţia Română pentru Cosmonautică şi Aeronautică (ARCA) or Romanian Cosmonautics and Aeronautics Association is a non-governmental organization that promotes aerospace projects as well as other space-related activities. It is based in Râmnicu Vâlcea, Romania.

Beginnings

In Sibiu, Romania, in front of the Hermann Oberth memorial house, a group of students decided to intensify the low-level space activities in Romania. ARCA's members started to develop an ambitious high-performance rocket engine in 1998. ARCA was registered in 1999. Since then, ARCA became a united team and, despite a small budget in the first years, it succeeded in leading the field in rocket technology in Romania.

The first aerospace project started in 1998 was a high performance rocket engine designed to deliver 85,000 kgf. The engine used open cycle and the 4 burning chambers were fed with liquid oxygen and kerosene at the combustion pressure of 70 bars.

The purpose of this project was to develop the abilities and skills needed for future activities by using local technology and materials. Another achievement was the creation of a united and specialized team of rocket engineers.

ELE and HAAS

The crew cabin

The most important goal of the whole project is safety. Therefore, safety and backup systems for the pilot were designed for every stage of the flight. With the cabin placed at the bottom of the ship, the abort sequence has a simple procedure: the crew cabin can be gravitationally separated from the rocket booster and recovered with its parachute. The cabin offers protection for almost the entire flight sequence, even in unlikely events like complete equipment failure, structural damage, etc.

The cabin is pressurized at 0.8 atm and contains navigation, flight control and life support systems. It is designed for one pilot that sits on a chair, specially designed for flight accelerations. The access inside the cabin is assured by a lateral auto-pressurized hatch which can be opened both from inside and outside of the cabin. As an added safety, the pilot will use a pressurized suit, offered by another former X Prize competitor, which has a lot of experience with pressurized suits: DeLeon Company. DeLeon and ARCA are partners since 2005 and they are collaborating on various aspects regarding the manned space flight.

The pilot has a panoramic view through three portholes. The position of the portholes was chosen in order to offer the pilot a complete view without it being necessary to raise from his chair. The top engine with its four nozzles could offer a beautiful view for the passenger, since the exhaust, made of oxygen and water vapors will freeze immediately after ejection, in contact with the outside environment (-60 degrees C). The jet will form small ice particles on which the Sun will reflect. After engine stop and capsule release, the pilot could maneuver the cabin with the RCS to have a view of the Earth with the four engine traces of ice beneath the ship.

The carrier balloon

The carrier balloon used to raise the ship at the launch altitude is a zero pressure Solar Montgolfier type, made of 15µm high density polyethylene. The balloon uses the Sun radiation to heat the inside air. This will lead to a temperature gradient between the interior and the exterior of the balloon. This gradient has a maximum value of around 30 degrees C, which makes the air from the inside to have a lower density comparing with the outside air. The balloon used for the Mission5-8 flights has a capacity of 350.000mc. It will be the biggest balloon of this type ever built.

The STABILO 1B System

This variant is different compared with the initial variant because of the rocket engine position. This allows a lower fuel consumption and the possibility to use a hot rocket engine. The crew cabin and the fuel tank are almost similar with the initial variant.

Stabilo flight program

Orizont

The construction of ORIZONT began in mid-2004. At that time, ARCA was more concerned with the launch of Demonstrator 2B from Cape Midia and most of the members declined involvement in the ambitious ORIZONT project. However, a small group started the design and the construction of the new vehicle.The first element was the mold for the pressurized compartment of the spacecraft. The mold and the whole structure of the cabin were finished in February 2005.

The work itself was done in a very small workshop and it was obvious that the team needed a much larger space for the equipments and hardware.

At the beginning of June one of the major sponsors of ARCA offered an assembly facility of 1500m². Here, they began assembling the ORIZONT vehicle.

Launch

The air-launch solutions are flexible due to the variable geometry of the wings and the solutions that were selected for the propulsion system. The launch can be executed, depending of the carrier availability, from helicopter or airplane. In every situation the launch will be made with the wings at near 0 degrees sweep angle because it is necessary that the wing generates the highest possible lift. In the case of helicopter launch, the ORIZONT vehicle will be lifted to an altitude of around 2,000-2,500 m. At this altitude, the vehicle will be released and will gravitationally accelerate to the required speed of about 210 km/h, necessary for the stable flight. In the case of the air launch, the ORIZONT vehicle will be transported to altitudes around 11,000 m, attached to the carrier at the top or at the bottom. Due to safety reasons, it is better to attach the vehicle at the bottom of the carrier. The launch from the helicopter is easier to implement from the logistical and technical point of view, but increases the stress of the pilot, because of the necessity to fly the ship in the atmosphere for a longer period of time.

Autonomous atmospheric flight

After the carrier release, the ORIZONT vehicle will start the air-breathing engine and will start to climb with the wings completely open to an altitude of around 17,000 m with a speed range of about 400-700 km/h. The maximum acceleration for this stage of the flight will be no higher than +4.6/-1.6 G

Rocket engine

Immediately after the vehicle reaches the desired altitude, the air-breathing engine will be detached. This action is shortly followed by the modification of the wing sweep angle to a minimum value. The lift and drag will decrease significantly.

Rocket engine vertical flight

The rocket engine will be started when ORIZONT will have 45 degrees angle of attitude which can be obtained from the stabilizers. Immediately after the start, the vehicle will begin to accelerate rapidly, the aerodynamic surfaces putting the vehicle to a near vertical trajectory. This trajectory will be kept for the entire time of the rocket engine run.

Inertial vertical flight and the reentry preparations

After the rocket engine shut-down, the ship will continue to climb inertly in a vertical position; in this time frame, the pilot will start the reconfiguration of the whole ship for re-entry mode: the wing sweep angle will be changed to a negative position and the stabilizers will change their position by 180˚. The low atmospheric density at that altitude will not allow the pilot to control the altitude of the ship from the aerodynamic surfaces and the ship will be controlled with the reaction control system (RCS).

Flight

At the maximum altitude of 100 km, the ship will have the lowest speed in the entire flight sequence. The pilot will continue to control the ship with the RCS.

Re-entry

After reaching the 100 km altitude, the vehicle will start the descent. For less than half the distance, the pilot will experience the effects of weightlessness. The ship must be kept with the RCS in a vertical position with the nose up. This process does not require an intense effort from the pilot since, to some degree, even big altitude errors are allowed. When the ship encounters the first dense atmospheric layers the use of the RCS becomes unnecessary;the ship, due to the unique variable geometry system, will become auto-stabilized aerodynamically and inert. The maximum deceleration at reentry will reach -6.2 G for only 4 sec.

Recovery

Even though the variable geometry of the vehicle would allow a landing procedure on a runway, ARCA decided that the parachuted recovery system is safer from the following considerations:

*Iin the case of a trajectory error during the rocket engine powered flight, the vehicle could be deviated far away from the runway

*The necessity of a runway presence limits the flight corridor definition possibilities.

*The stress for the pilot is lower because the necessity of a runway landing procedure is suppressed.

*It offers the possibility to abort the mission in almost every sequence of the flight and to bring the ship safely to the ground.

The deceleration parachute will be extracted at a height of about 6.000 m and this operation is shortly followed by the main parachute extraction ,at 4000 m. The whole parachute system is placed in the front of the ship, at the bottom of the cabin.The landing in the sea will take place at a speed no higher than 7m/s.The stress over the pilot, from the rocket engine shut-down to the landing moment is reduced significantly.

Early Vehicles

Demonstrator

This technological demonstrator is at 1:2 scale of that of the X PRIZE vehicle, named Orizont and it is the first rocket designed by ARCA Team. It is an unguided but self-stabilized rocket. On this vehicle and on the sub-assembly systems many constructive solutions were tested, especially composite materials fuel tanks. Almost the entire structure is made of composite materials, but also from aluminium aloys. This rocket was created to simulate an almost complete (unmanned) X Prize mission. Demonstrator 1 was also used in public exhibitions in order to attract more funds for ARCA projects.

The old configuration used a liquid fuel rocket engine, designed to thrust 2,000 kgf during 60 sec.The fuel was: hydrogen peroxide 85% + T1. In the new configuration will use a hybrid engine with hydrogen peroxide 85% as an oxidizer, in combination with polyethylene as fuel.

Demonstrator 2

The technological demonstrator "2" is at 1:2.5 scale of that of the X PRIZE vehicle, named Orizont. ARCA started the work to this rocket in May 2003. The entire structure is made of composite materials. For this vehicle was created a whole launch complex, including the launch pad, the fuel transfer facility, etc. For this vehicle two propulsion configurations were proposed: monopropellant and hybrid.

Demonstrator 2 was the starting point for the development of the successful Demonstrator 2B rocket. The first public display of this vehicle took place in Drăgăşani, on September 27 2003.

Demonstrator 2B

Demonstrator 2B is a modified version of Demonstrator 2, equipped with the world's first reusable rocket engine made of composite materials. The main objective of this rocket was to test in flight the engine and the vehicle-launch pad interaction in order to gather more data for the Orizont vehicle construction. For the Demonstrator 2B launch was used the Demonstrator 2 launch pad which was modified (the length was increased to 18.2 m) and also the command panel and fuel transfer facility previously developed at ARCA.

This rocket was the end of subscale systems tests at ARCA and the beginning of the Orizont vehicle's final phase of construction.

The Demonstrator 2B rocket was successfully launched on September 9, 2004. The measurements indicated that the launch parameters were: 1000 m altitude, 630 km/h, 2100 m range.

Governmental contracts

STRACAAT

In November 2005 ARCA succeeded to win a contract with the Research Ministry/Romanian Space Agency for the development of a rocket system with military applications. The contract was awarded for a period of 12 months.ARCA’s military application rocket was presented to the Bucharest International Fair on October 3 2006. The rocket financed by the government through the Romanian Space Agency- “SECURITY” Program, has a length of 4.1 m and is designed to fly with Mach 1.02 at sea level. The maximum flight altitude is 6.000 m. The main purpose of this project is to create a target able to simulate low altitude/high speed aggressor vehicles.

BASMATES

High Altitude Commercial Solar Balloon for Scientific Equipmant - BASMATES project consists in designing, constructing, launching and recovering a high altitude solar baloon and presurized capsule, built for transporting scientific and commercial payload. This program started in 2007 and has a duration of 30 months.

VECSS

The project „Vehicle for commercial operation of suborbital space – VECSS” consists in designing, accomplishing, lanunching and recovering from suborbital flight, of a vehicle intended for transportation of scientific commercial payload, to 100 km altitude. This program started in 2007 and has a duration of 36 months.

Lunar X-Prize competition

The agency has committed itself as a competitor in the Google Lunar X-Prize. [citeweb|title=Private race to the moon (and money) takes off|url=http://www.msnbc.msn.com/id/23278871/page/2/|publisher=msnbc.com|accessdate=2008-02-22] ARCA, the first European Union team to register for the competition, has a unique approach to completing their objective.citeweb|title=LATEST NEWS|url=http://www.arcaspace.ro/orbital/en/home.htm|publisher=arcaspace.ro|accessdate=2008-02-23] The project is labeled "HAAS-ELE" and consists of a (high altitude) balloon-launch for a three-stage rocket.

ee also

*Romanian Space Agency

References

External links

* [http://www.arcaspace.ro ARCA site]
* [http://www.xprize.com/ Ansari X Prize official site]
* [http://www.spacefellowship.com/News/?cat=4 Latest ARCA Space, Space Fellowship news]
* [http://www.googlelunarxprize.org/ Google Lunar X Prize official site ]
* [http://www.cnmp.ro:8083/pncdi2/program4/ National Plan for Research Development and Innovation]