||This article includes a list of references, but its sources remain unclear because it has insufficient inline citations. (February 2011)|
|Industry||Aerospace and space tourism|
|Key people||Dumitru Popescu|
Asociația Română pentru Cosmonautică și 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.
- 1 Private space program
- 2 IAR-111 Excelsior and HAAS II
- 3 ELE and HAAS
- 4 Stabilo
- 5 Orizont
- 6 Helen and Helen 2
- 7 Popescu-Diaconu stabilization method
- 8 Early vehicles
- 9 Government contracts
- 10 Lunar X-Prize competition
- 11 Flights
- 12 See also
- 13 Notes
- 14 References
- 15 External links
Private space program
ARCA announced in March 2012 that it has initiated a private space program (called the Romanian Space Program, as the Romanian Space Agency runs its state program through the ESA) with a number of short-, medium-, and long-term objectives:
- The short-term objectives involve finishing the Executor engine, the IAR-111 carrier plane, and the Haas-2 rocket. These will be used to launch the ELE probe to the Moon's surface as part of the Google Lunar X-Prize.
- The medium-term objective is to develop a manned crew cabin that is to be launched on suborbital flight at 180 km by a Haas-2b rocket.
- In the long term (2020s), ARCA is to develop a medium-launch vehicle called the Super Haas. This is a two-stage rocket that consists of a lower stage that groups seven Haas-2 or Haas-2b rockets and an upper stage that uses two Executor Plus engines optimized for thrust in a vacuum. The Super Haas is supposed to generate 260 kN of thrust at launch and can place a 2.6 metric ton load into low earth orbit.
IAR-111 Excelsior and HAAS II
The problems and delays faced by ARCA while attempting to launch rockets using balloon carriers prompted the development of an alternative launching device. The IAR-111 Excelsior rocket plane had been secretly in development since early 2010.
ELE and HAAS
|Full weight:||23,300 kg|
|ELE weight:||400 kg|
|ELL weight:||42 kg|
|Stages:||3 booster + 3 space probe|
|Type:||Rocket powered, pressure feed|
|Fuel:||Hydrogen peroxide + paraffin wax|
|Stage 2 thrust:||24,800 kgf|
|Stage 3 thrust:||5,850 kgf|
|Stage E1 thrust:||500 kgf|
|Stage E2 thrust:||100 kgf|
|ELL thrust:||14 kgf|
|Maximum weight:||1,000 kg|
|Acceleration (boost phase) :||4G|
|Max speed:||4,500 km/h|
|Max altitude:||100 km|
The ARCA team proposes a new suborbital ship concept. The engine, placed at the top of the ship, gives an unconventional aspect to this spaceship.
The tractor engine offers the possibility to place the crew cabin at the rear of the ship, which offers extended abort capabilities. STABILO will be launched in a vertical position. In this situation, pilot activities are highly reduced.
STABILO was designed to be launched from an altitude of 22,000 m in two stages. The first stage consists of a 1 hour, 35 minute ascension with a 350,000 m3 Solar Montgolfier balloon to the altitude of 22,000 m (66,000 feet). The second stage commences by launching the suborbital vehicle vertically, through the very thin balloon envelope. At the bottom of the balloon, a composite-material ring 2 m in diameter allows the STABILO to enter into the balloon envelope.
|Length:||6 m|
|Maximum weight:||1000 kg|
|Acceleration (boost phase):||4G|
|Max speed:||4,500 km/h|
|Max altitude:||100 km|
The most important goal of the 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 who sits on a chair, specially designed for flight accelerations. Access inside the cabin is assured by a lateral auto-pressurized hatch that can be opened from inside and outside the cabin. For added safety, the pilot will use a pressurized suit, offered by another former X Prize competitor, which has much experience with pressurized suits: Pablo de León and Associates. De León and ARCA have been partners since 2005, and they are collaborating on aspects regarding manned space flight.
The carrier balloon used to raise the ship to the launch altitude is a zero pressure Solar Montgolfier type, made of 15 µm high density polyethylene. The balloon uses the Sun's 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 inside have a lower density compared with the outside air. The balloon used for the Mission 5 to Mission 8 flights has a capacity of 350.000mc. It will be the biggest balloon of this type ever built.
|Specific impulse:||110s|
|Fuel for jet engine:||T1+ oxygen from atm|
|Max altitude:||100 km|
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.[dated info]
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 a sweep angle of nearly 0 degrees, 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 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. For safety reasons, it is better to attach the vehicle at the bottom of the carrier. Helicopter launch is easier to implement from the logistical and technical points of view but increases the stress of the pilot because of the necessity to fly the ship in the atmosphere for a longer 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.
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.
Helen and Helen 2
The Helen vehicle was supposed fly on Mission 3 with the ELL avionics payload transported, while the Stabilo vehicle will be used for future manned flights. Helen was to be transported to 14000 m via a solar carrier balloon. After the failure of Mission 3, due to an unexpected twisting of the solar balloon, and the failure of Mission 4 due to a rupture in the helium balloon, Helen 2 was transported on Mission 4b by another helium balloon on October 1, 2010 to 14000 m. It successfully flew to 40 km, but the capsule was not recovered. This wasn't a problem, as data had been transmitted live to the ARCA command center.
Popescu-Diaconu stabilization method
Several of ARCA's vehicles use a purported "gravitational stabilization" technique involving using a tractor configuration similar to that attempted in early rocketry experiments. ARCA's claim is that a towed mass provides stabilization in a gravity field without use of aerodynamic surfaces or reaction jets. However, this is simply a variation of the pendulum rocket fallacy, in which the towed mass is mistakenly viewed as hanging below the rocket engine and pulling it toward vertical. In reality, gravity works on the vehicle as a whole. ARCA claims to instead use the gravitational gradient. While forces from gravitational gradients do exist, and are used for satellite stabilization, the restoring forces are far too small to be of use for stabilizing rocket vehicles during launch or landing. ARCA's vehicles using this method are un-stabilized.
This technological demonstrator is at 1:2 scale of that of the X PRIZE vehicle, named Orizont (translated Horizon), and it is the first rocket designed by the ARCA team. It is an unguided, 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 and from aluminium alloys. This rocket was created to simulate an almost complete (unmanned) X Prize mission. Demonstrator 1 was also used in public exhibitions to attract more funds for ARCA projects.
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 a whole launch complex, including the launch pad, the fuel transfer facility, etc. was created. Two propulsion configurations were proposed: monopropellant and hybrid.
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 to gather more data for the Orizont vehicle construction. The Demonstrator 2B launch 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.
In November 2005 ARCA won a contract with the Research Ministry/Romanian Space Agency for the development of a rocket system with military applications. The contract was awarded for 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.
Lunar X-Prize competition
The agency committed itself as a competitor in the Google Lunar X-Prize. ARCA, the first European Union team to register for the competition, had a unique approach to completing their objective. The project is labeled "HAAS-ELE" and consists of a (high altitude) balloon-launch for a three-stage rocket. The new approach consists of using a supersonic rocket plane to get the HAAS II and its payload to 16 km before launch.
|Flight||Program||Category||Altitude/destination||Ship configuration||Engine start||Status|
|First Flight||Demonstrator 2B||Unmanned||1.000 m||Ground-launched rocket||Yes||Completed|
|Mission 1||Stabilo||Unmanned||22.000 m||Carrier balloon + Crew cabin||No||Completed|
|Mission 2||Stabilo||Unmanned||22.000 m||Carrier balloon + Complete ship||No||Completed|
|Mission 3||Lunar Project (Helen Test Rocket)||Unmanned||100.000 m||Carrier balloon + Helen (3 stages)||Yes||Unsuccessful|
|Mission 4||Lunar Project (Helen 2 Test Rocket)||Unmanned||100.000 m||Carrier balloon + Helen 2 (2 stages)||Yes||Unsuccessful|
|Mission 4b||Lunar Project (Helen 2 Test Rocket - single stage)||Unmanned||40.000 m||Carrier balloon + Helen 2 (1 stage)||Yes||Completed|
|Mission 5||Avionics & TV transmission test||Manned||5.000 m||Carrier balloon + Stage 1 (Helen 2) + ELL||No||Completed|
|Mission 6||Cabin drop safety test||Unmanned||700 m||IAR-111 cabin (dropped by helicopter)||No||Completed|
|Mission 8||Equipment test (Propulsion and data transmission)||Unmanned||Stratospheric||Payload with undisclosed rocket||Yes||Completed|
|CubeMessenger (BOREAS)||Space launch||Unmanned||Orbital||Haas 2C||TBL||TBL summer 2013|
|Mission 7[a]||Carrier plane test||Manned||16.000 m (?)||IAR-111||TBL||TBL 2013|
|IAR-111 orbital payload placement||Orbital placement test||Manned (IAR only)||100+ km||IAR-111 & HAAS II||TBL||TBL 2013|
|Moon Mission||X-Prize Flight||Manned (IAR only)||Lunar Surface||IAR-111 & HAAS II - ELL||TBL||TBL 2014 |
- According to the mission patches found on the ARCA website, the IAR-111 test flight will be named Mission 7.
- "ARCA_HOME". ARCA. 2012-02-10. Retrieved 2012-02-10.
- http://arcaspace.ro/ro/comunicat_presa_mis4b.doc Comunicat de presă ARCA 4 octombrie 2010 [ro]
- "Private race to the moon (and money) takes off". msnbc.com. Archived from the original on 27 February 2008. Retrieved 2008-02-22.
- "LATEST NEWS". arcaspace.ro. Retrieved 2009-10-07.[dead link]
- "Arca (Team) Google Lunar XPRIZE". googlelunarxprize.com. Retrieved 2014-06-20.
- "ARCA_HOME". ARCA. 2009-11-14. Retrieved 2010-10-04.
- "ARCA va lansa satelitul bulgaresc CubeMessenger" [ARCA CubeMessenger Bulgarian satellite launch] (in Romanian). ARCA. 2012-08-03. Retrieved 2012-08-04.
- ARCA site Eng
- Ansari X Prize official site
- Latest ARCA Space, Space Fellowship news
- Google Lunar X Prize official site
- National Plan for Research Development and Innovation