Automated Transfer Vehicle

Automated Transfer Vehicle
Description
Role:	Supply the International Space Station with propellant, water, air, payload and experiments.
Crew:	Unmanned
Dimensions
Height:	Template:Dist m ft
Diameter:	Template:Dist m ft
Payload:	9,000 kilograms (20,000 lb) (approx.)
Performance
Endurance:	Docked with the ISS for six months
Apogee:	400 km
Perigee:	300 km
Inclination:	51.6 degrees

Water tank

Fuel tank

File:Atv comparision.jpg

ATV vs Apollo vs Progress

An Automated Transfer Vehicle or ATV is an unmanned resupply spacecraft developed by the European Space Agency (ESA). ATVs are designed to supply the International Space Station (ISS) with propellant, water, air, payload and experiments. In addition, ATVs can re-boost the station into a higher orbit.

The first ATV, Jules Verne, was launched March 9, 2008 by an Ariane 5 from Guiana Space Centre in Kourou, French Guiana. Lift-off occurred at 04:03 UTC (01:03 local). It will perform tests in orbit and then wait for Space Shuttle Endeavour to depart before automatically docking on April 3 to Zvezda, a Russian component of the station. €1.3 billion EUR (£990 million GBP, $2 billion USD) was spent by the ESA on the ATV programme.

Beyond Jules Verne, ESA has already contracted industry to produce four more ATVs to be flown through to 2015. A total of seven ATVs could eventually be launched to the ISS, mission managers said.

Design

The ATV is designed to complement the Progress spacecraft, having three times its capacity. Like the Progress, it carries both bulk liquids and relatively fragile freight which is stored in a cargo hold kept in a pressurized shirt sleeve environment so that astronauts can have access to it without putting on a spacesuit. The ATV pressurized cargo section is based on the Italian-built Multi-Purpose Logistics Module (MPLM), which is already in service as a Shuttle-carried ‘space barge’ transporting equipment to and from the Station.

ATV incorporates a Russian-built automatic docking system, similar to those used on Soyuz manned ferries and on the Progress re-supply ship. Also like the Progress, the ATV will additionally serve as a container for the station's waste.

Each ATV weighs 20.7 tonnes at launch and has a cargo capacity of 9 tonnes:

• 1,500 kilograms (3,300 lb) to 5,500 kilograms (12,100 lb) of dry cargo (re-supply goods, scientific payload, etc.),
• Up to 840 kilograms (1,850 lb) of water,
• Up to 100 kilograms (220 lb) of gas (nitrogen, oxygen, air), with up to two gases per flight,
• Up to 4,700 kilograms (10,400 lb) of propellant for the re-boost maneuver and refueling the station. The ATV propellant used for re-boost (monomethylhydrazine fuel and N₂O₄ oxidizer) is of a different type from the payload Russian refueling propellant (UDMH fuel and N₂O₄ oxidizer).

After undocking, the ATV is led to a controlled burn-up in the atmosphere, along with up to 6.5 tonnes of waste.

Development

The prime contractor for the ATV is EADS Astrium Space Transportation, leading a consortium of many sub-contractors. The prime contractor office is currently located in Les Mureaux, France, and will be transferred to Bremen, Germany, once the development is completed and the production of the four initial units starts. In order to facilitate the relationship between the contractor and ESA, an integrated ESA team at the Les Mureaux site has been established for the duration of the development.

The first ATV arrived at the ESA spaceport in Kourou, French Guiana on 31 July 2007 after a nearly two week journey from Rotterdam harbour and was launched on March 9, 2008. The Jules Verne was the first ATV to be launched. Astrium Space Transportation builds the ATVs in its facility in Bremen. Contracts and accords were signed in 2004 for four more ATVs, which should be launched about once every two years, bringing the total order, including Jules-Verne, to five.

To this end, RSC Energia has signed a 40 million euro contract with one of the main subcontractors of EADS Astrium Space Transportation, the Italian company Thales Alenia Space, to supply the Russian Docking System, refuelling system, and Russian Equipment Control System. Within the EADS Astrium Space Transportation led project, Thales Alenia Space is in charge of the pressurized cargo carrier of the ATV. These pressurized cargo carriers are produced in Turin, Italy.

Missions

#	Launch date	Designation
1	March 9, 2008 4:03 UTC	Jules Verne
2	2009 (planned)	ATV-2
3	2011 (planned)	ATV-3
4	2012 (planned)	ATV-4
5	2013 (planned)	ATV-5
6	TBD (possible)	ATV-6
7	TBD (possible)	ATV-7

Jules Verne

Main article: Jules Verne ATV

Automated Transfer Vehicle

The first flight of the ATV was delayed many times and launched on March 9, 2008. It is named Jules Verne, in memory of the first science fiction writer of modern times and carries two of the author's original handwritten manuscripts, to be received by the ISS crew as symbolic tokens of the success of the first flight.

The craft was launched into a 300-km orbit atop an Ariane 5 from the equatorial ELA-3 launch site at the Guiana Space Centre in Kourou. After the ATV had separated from the Ariane rocket 1 hour 6 minutes and 41 seconds into flight, navigation systems will be activated and thrusters will fire to boost the ATV into the transfer orbit to the ISS. After three weeks of orbit adjustments, the ATV will be about 39 km behind and 5 km below the Station.

The Jules Verne will use GPS and a star tracker to automatically rendezvous with the Space Station. At 249 meters two other systems take over and control the final docking manoeuvers. The videometer fires laser pulses at 26 cube-shaped reflectors installed on the Zvezda service module. A radar-like telegoniometer is also installed as a secondary control system.

The actual docking to Zvezda will be fully automatic. If there are any last-minute problems, a pre-programmed sequence of anti-collision manoeuvres, fully independent of the main navigation system, can be activated by the astronauts aboard the station.

With the ATV docked, the Station crew will enter the cargo section and remove the payload. The ATV's liquid tanks will be connected to the Station's plumbing and discharge their contents. The Station crew will manually release air components directly into the ISS’s atmosphere. For up to six months, the ATV, mostly in dormant mode, will remain attached to the ISS with the hatch remaining open. The crew will steadily fill the cargo section with the Station's waste. At intervals of 10 to 45 days, the ATV’s thrusters will be used to boost the Station's altitude.

Once its mission is accomplished, the ATV, filled with waste, will be separated. Its thrusters will move the spacecraft out of orbit (de-orbit) and place the spacecraft on a steep flight path to perform a controlled destructive re-entry high above the Pacific Ocean.

Flight controllers are currently evaluating the failure of the number two Propulsion Drive Electronics (PDE) unit, which controls a quarter of the ATV's manoeuvring thrusters. All engine burns have been cancelled whilst the fault is investigated.

ATV Evolution projects

The European Space Agency was studying potential evolutions and adaptations of the ATV, following the decision by NASA to retire the Space Shuttle around 2010. Most of these evolutions have been dropped. Many of the studies were focused on the adaptation of the ATV in order to allow cargo return to Earth's surface.

• A first study was called PARES (PAyload REtrieval System), and would have included a small ballistic capsule similar to VBK-Raduga and embedded into the ATV docking interface, which would have brought back a few tens of kilograms of payload. PARES could have featured a deployable heat shield system. The European Space Agency was also proposing the system for use with the Progress spacecraft and the H-II Transfer Vehicle (HTV).

• The CARV (Cargo Ascent and Return Vehicle) study was investigating a larger lifting capsule, capable of bringing back a few tonnes of payload, which could have been installed in place of the ATV pressurized cargo hold. Such vehicles could have been available by 2010. However, the financial situation of ESA led to a priority given to PARES over the CARV. But finally, the PARES was not proposed by ESA for approval at the latest Ministerial conference of ESA.

• Possibilities of launching of the ATV on other launchers than the Ariane 5 have also been investigated, in particular in the frame of COTS, but NASA has meanwhile chosen to go for a US-only solution.

• Another ATV evolution concept under consideration for the future is an ATV with two docking ports, one at each end with the propellants around the cylindrical tunnel linking the end docking port to the main cargo area of the vehicle. This concept would allow Soyuz and Progress to dock to the back of the ATV allowing a steady flow of Russian vehicles using the available docking ports whilst an ATV is docked for an average of around 6 months at a time.

See also

• H-II Transfer Vehicle – a similar ISS cargo vehicle being developed by the Japan Aerospace Exploration Agency (JAXA), first flight scheduled for 2009.
• Commercial Orbital Transportation Services – NASA initiative to create a commercial cargo and crew transportation capability to and from the ISS.
• Progress spacecraft – Cargo spacecraft currently operated by the Russian Federal Space Agency Roskosmos.

External links

• ""Automated Transfer Vehicle, Rev 1.2"" (PDF). esa.int. European Space Agency. Retrieved 2008-03-09.
• ESA's description of the ATV
• ESA's ATV operations page
• ATV press kit by EADS Astrium
• Space.com's Progress Made for Launch of Europe's Delayed ATV
• Alenia Spazio to build 6 ATVs
• ATV Integrated Cargo Carrier
• First ICC
• ATV spacecraft subassembly
• European companies working on ATV
• ESA: ATV Evolution Scenarios
• BBC article about the ATV