Como já falei algumas vezes neste blog, o Projecto Orion pouco mais é que um projecto Apollo 'actualizado'.
Mas esta palavra 'actualizado' tem alguns problemas. Por exemplo, supõe que a tecnologia tenha evoluido muito entre os anos 60 e o século XXI. Mas infelizmente, o progresso tecnológico que se verificou nestes 40 e poucos anos residiu quase por inteiro no domínio dos computadores e micro-electrónica. Tudo o resto - sistemas de propulsão, sistemas de protecção térmica, sistemas de habitação no espaço - não teve quase progressos nenhums!
Apenas nos últimos anos temos visto alguns progressos, incrementais - como todos os progressos dignos de nota - no sistema do Space Shuttle e da Estação Espacial Internacional. O Space Shuttle é, hoje em dia, um sistema completamente diferente do que era há 25 anos. Todos os Space Shuttles foram completamente renovados no interior, com novos sistemas electrónicos, de navegação, pilotagem, gestão de energia, etc.
Ora é precisamente numa altura em que os progressos se começam a ver que a NASA, a mando do Presidente George Bush, irá cancelar o projecto Space Shuttle, para regressar atrás mais de 40 anos!
Bom sinal disto tem sido a evolução muito acidentada do projecto Orion. A cápsula é, já em si, um desenho antiquado. A NASA afirmou que a Orion seria 'uma Apollo em esteróides'. Seria uma versão substancialmente maior da cápsula Apollo.
Mas o que se tem visto têm sido sucessivas reduções de tamanho e de peso, demonstrativas dos sucessivos erros de cálculo - e falta de experiência - de quem a está a desenhar!
A aterragem de uma Orion - em terra firme - como foi originalmente planeada.
A aterragem de uma cápsula Apollo, há quase 40 anos.Tal como as da Orion serão...
Não será necessário pensar muito no custo que isto vai acarretar! As cápsulas terão de ser recuperadas pela Marinha dos EUA, geralmente por porta-aviões... Nem vou comentar mais. Começa a ser excessivamente óbvio que uma missão da Orion será pelo menos tão cara como qualquer missão do Space Shuttle...
Não seria melhor continuarmos ou desenvolvermos o que já conhecemos? Ou tentarmos fazer algo de novo? Em vez de metermos o rabo entre as pernas e fujirmos para o passado?
Please, NASA, stop the Orion project while you can! Do something new! Even if it takes time!
Link: NASA Spaceflight
Orion landings to be splashdowns - KSC buildings to be demolished
By David Harris / Chris Bergin, 8/5/2007 3:55:40 PM
NASA Constellation and Lockheed Martin have deleted the airbag landing system from the next Orion design cycle (Orion 607) in a weight saving measure, opting to return to an Apollo-style splashdown for the vehicle's end of mission.
Meanwhile, a list of shuttle facilities at the Kennedy Space Center (KSC) that will be demolished between 2010 and 2012 - including all three Orbiter Processing Facilities (OPFs) - has been produced.
The water landing scenario - previously only required during a launch abort - is one of several items that are being baselined into the next design cycle as a weight savings measure.
The deletion of landing airbags - and reduction of Orion structure - will aid the requirement Lockheed Martin engineers have been given to reduce the mass of Orion, allowable because of the 'softer' water landings.
Previously, the Orion was designed to land on large airbags at a landing range, although earlier hints that was no longer going to be the case came via documentation that showed a water landing - off the coast of Australia - for the Orion 3 unmanned test flight in September 2012. The first manned flight, Orion 4, was due to land at Edwards Air Force Base.
Also part of the mass saving design cycle - knocking off a total of 1,200 lbs from Orion - is the deletion of green propellants on the Crew Module, returning to the tried and tested hypergolic Reaction Control Systems (RCS). This weight savings measure was made in-line with the change to a water landing, due to salt water's neutralizing of potential hypergolic fuel spills after splashdown.
Other information acquired by NASASpaceflight.com's L2 section notes the continuing efforts of scheduling the transition between Shuttle and Constellation, referencing the changes that will be made to KSC, post-Shuttle.
Those evaluations have concluded with the decision that all three OPF's will be demolished between 2010 and 2012, in addition to the Hypergol Maintenance Facility (HMF) and SSME (Space Shuttle Main Engine) work shop.
At the Shuttle Landing Facility, the shuttle specific landing aids will be taken down in addition to the Orbiter Mate-Demate Device. All TAL sites will be abandoned, as they belong to the foreign nations.
Some facilities that may be modified to support Constellation include the STS Flight Simulator (Orion simulators), Space Station Processing Facility (Station support until de-orbit and possible use for Orion processing), and the Payload Canister Rotation Facility. Their fates are currently classed as 'undecided.'
Modifications to the sound suppression system at Pad 39B and the MLP (Mobile Launch Platform) are scheduled to be finished by the beginning of next year, ahead of the 2008 test flight of the Ares I-X. LCC (Launch Control Center) firing room 1 will be activated in August 2008.
The FSS (Fixed Service Structure) modifications to support interface with the dummy upper stage and flight monitoring equipment of the Ares I-X will be completed by Jan. 2009. The lightning mast on the FSS and the VAB high bay 3 work platforms are also scheduled for Jan. 2009.
Other information notes that the Mobile Launcher for Ares 1 - currently at the 60 percent stage of its design review - will have a total rollout mass, including vehicle, of around 12.5 million pounds (567,000kg). For comparison, Saturn V had a total rollout mass of 12.63 million pounds and the shuttle has a rollout mass of 12.02 million lbs.
The dry weight of the Ares I will be 2.2 million lbs (1,000,000 kg), and the tower will weigh 2 million lbs (907,000 kg). The rest of the weight is in the MLP base, support systems, and ground support equipment.
The interstage design for Ares I is also progressing. At 5.5 meters in diameter and 5.7 meters in length, it will house four Booster Deceleration Motor pods (for SRB staging) and two RCS (Reaction Control System) pods for roll control.
The Preliminary Design Review (PDR) for Ares I is scheduled for mid 2008, with a Critical Design Review (CDR) in early 2010. Transition from Ares I design to Ares V design is to start in 2011 and fully transition in 2013. Ares V-Y (Dummy upper stage) is scheduled for mid 2018 with Orion 13/LSAM 1 being the first moon flight in late 2018, although that schedule is deemed ambitious, due to budget constraints.
MCC (Mission Control Center) will be conducting a flight, following on Ares 1-X, with some control on Ares 2, and full control on Ares 3 (first real flight). MCC and Crew procedure development will start early next year, and full flight crew training will begin in 2011.
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