In article m,
says...
On 2016-01-02 11:35, Jeff Findley wrote:
It's a propulsion module! It doesn't care *where* it goes, it just
fires its engines and/or RCS thrusters when commanded!
Does this mean that the autopilot logic used for ATV to get to station
vicinity will not be used and all the logic will be done by Orion and
written by NASA ?
Unsure. But, with astronauts on board, there will most certainly be a
"manual override" for any scenario where the automatic systems don't
operate as intended.
Are the ATV engines as powerfull as the Apollo service module ? Or is
that not necessary because they can just fire for longer period ?
The Apollo SM engine was sized to place a fully fueled LEM into lunar
orbit. Orion won't be doing anything quite like that for a Mars
mission. ATV derived engines are more than capable for what Orion is
planned to do.
http://www.esa.int/Our_Activities/Hu...s_European_mod
ule_ready_for_testing
Thanks for the link. I had the impression that this was must a shape
mockup, but this test article seems faily well popuylated even with the
thruster nozzles.
Would the test article contain any electronics to ensure they survice
the shake/bake testing ?
One thing that struck me:
##
The module sits directly below Orion?s crew capsule and provides
propulsion, power, thermal control, and water and air for four
astronauts. The solar array spans 19 m and provides enough to power two
households.
##
I thought Orion was designed for 7 cremembers ? has NASA silently
reduced crew capacity to 4 ? Just an error on ESA,s web page ? Or are
there plans for a 2nd generation service module that will support 7
crewmembers ?
Duration would depend on the mission and size of crew (the space shuttle
flew with various crew sizes too).
NASA has been trusting the lives of its astronauts inside ESA
modules for decades!
Am not debating ESA's capabilities. Just being realistic on the
integration problems with a totally new vehicle.
Except the Orion service module is not totally new. It's directly
derived from the ESA ATV's service module since it serves almost exactly
the same role.
BYW, how does the service module connect with Orion ? a trap door in the
heat shield where O2, N2, electrical, water, data connect ? Once Orion
separates, the trap door closes ?
Possibly. The shuttle did that, and so did Blue Gemini (which was test
flown). Either that or an umbilical that wraps around the edge of the
heat shield just like on the Apollo CSM design. NASA has two options
here that have both been flight proven.
But, Congress is hell bent on continuing funding for SLS so I really
don't see that happening unless something really bad happens with SLS
(like it goes *boom* on its first test flight).
It is a fair bet that NASA will get to destroy the remaining shuttle
engines. Once NASA goes to congress to ask for more SSMEs to be built,
the buck may stop there.
I take it Boeing is the main beneficiary of a contract to build more
SSMEs ?
No, Boeing does not make large liquid fueled engines. The contract went
to Aerojet Rocketdyne, the same company which produced the original
SSMEs.
https://www.rocket.com/article/nasa-...cketdyne-sign-
contract-restart-production-rs-25-engine-space-launch
Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer