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...Ares1-X FAILURE...N KOREA Offers NASA Technical Advice~



 
 
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  #11  
Old November 1st 09, 08:57 PM posted to sci.space.policy,sci.space.shuttle
John Doe
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Posts: 1,134
Default Ares1-X failure - new information

Derek Lyons wrote:

Because the pad is fixed - while a vehicle launched from it may depart
on any number of different azimuths. Therefore the vehicle rolls to
align the vehicles various axes with the with the trajectory. This
also helps ensure communications with the vehicle as various antenna
are pointed in the proper direction.


Since this is a round cylinder, why not just place the rocket on the pad
in the right roll orientation to begin with ? I realise this may require
some planning, such as ensuring whatever connections to the tower are
placed accordingly (as well as placing the payload (Orion) in such a way
that its door faces the access arm).

So , what is the reason they couldn't orient the rocket on the pad to
remove the need for a 90° roll ?
  #12  
Old November 1st 09, 10:05 PM posted to sci.space.policy,sci.space.shuttle
Derek Lyons
external usenet poster
 
Posts: 2,999
Default Ares1-X failure - new information

John Doe wrote:

Derek Lyons wrote:

Because the pad is fixed - while a vehicle launched from it may depart
on any number of different azimuths. Therefore the vehicle rolls to
align the vehicles various axes with the with the trajectory. This
also helps ensure communications with the vehicle as various antenna
are pointed in the proper direction.


Since this is a round cylinder, why not just place the rocket on the pad
in the right roll orientation to begin with ? I realise this may require
some planning, such as ensuring whatever connections to the tower are
placed accordingly (as well as placing the payload (Orion) in such a way
that its door faces the access arm).

So , what is the reason they couldn't orient the rocket on the pad to
remove the need for a 90° roll ?


Because you have various and sundry connections between the vehicle
and the launch pad that can't be moved without extensive renovations
to the pad and extensive design changes to the vehicles - for each and
every flight.

It's much easier to roll.

D.
--
Touch-twice life. Eat. Drink. Laugh.

http://derekl1963.livejournal.com/

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL
  #13  
Old November 2nd 09, 01:05 AM posted to sci.space.policy,sci.space.shuttle
kT
external usenet poster
 
Posts: 5,032
Default Ares1-X failure - new information

John Doe wrote:
Derek Lyons wrote:

Because the pad is fixed - while a vehicle launched from it may depart
on any number of different azimuths. Therefore the vehicle rolls to
align the vehicles various axes with the with the trajectory. This
also helps ensure communications with the vehicle as various antenna
are pointed in the proper direction.


Since this is a round cylinder, why not just place the rocket on the pad
in the right roll orientation to begin with ? I realise this may require
some planning, such as ensuring whatever connections to the tower are
placed accordingly (as well as placing the payload (Orion) in such a way
that its door faces the access arm).

So , what is the reason they couldn't orient the rocket on the pad to
remove the need for a 90° roll ?


That's what I do, orient it straight east with the proper roll preset,
and then all you have to deal with is the pitch and the pitch rate.

I like to have pitch, pitch rate, altitude, velocity, acceleration and
elapsed time numerically on my HUD, as well as the usual visual pitch
and momentum vector targets. Of course, with a SINGLE high efficiency
closed combustion cycle regeneratively cooled high performance space
shuttle main engine for propulsion, you have to load the stack up with
payload and use big hydrocarbon boosters in order to prevent exceeding
your acceleration limits, and roll control is a definite problem that
has to be dealt with, otherwise you might indeed spin out of control
after you lose the boosters and really start to haul ass. That's why
there are pairs of outboard ground started OMS engines idling along as
roll control, and ready to do long deep throttling fuel settling and
scavenging burns too, and orbital tweaking and final circularization.

Once you achieve orbit and docking you just react or burn off your
residual fuel to boost the tank farm, and let the space port workers
handle to pesky details of dealing with the tank, payload and engines.

Engine into the nosecone and back to the ocean for quick pickup, and the
tank gets added to your vast orbiting space port and star trek vessels.
Excess fuel quickly burnt off for electricity and heat, and then you
drink and grow plants so that you don't need billion dollar resupply.

Those SRBs are gonna set us back another couple of decades again. Unless
you use them with a decent reusable hydrogen core, they just won't work.

The canceled the Saturn V for a reason, and they didn't even use SRBs.
  #14  
Old November 2nd 09, 02:38 AM posted to sci.space.policy,sci.space.shuttle
Jorge R. Frank
external usenet poster
 
Posts: 2,089
Default Ares1-X failure - new information

Derek Lyons wrote:
John Doe wrote:

Derek Lyons wrote:

Because the pad is fixed - while a vehicle launched from it may depart
on any number of different azimuths. Therefore the vehicle rolls to
align the vehicles various axes with the with the trajectory. This
also helps ensure communications with the vehicle as various antenna
are pointed in the proper direction.

Since this is a round cylinder, why not just place the rocket on the pad
in the right roll orientation to begin with ? I realise this may require
some planning, such as ensuring whatever connections to the tower are
placed accordingly (as well as placing the payload (Orion) in such a way
that its door faces the access arm).

So , what is the reason they couldn't orient the rocket on the pad to
remove the need for a 90° roll ?


Because you have various and sundry connections between the vehicle
and the launch pad that can't be moved without extensive renovations
to the pad and extensive design changes to the vehicles - for each and
every flight.

It's much easier to roll.

D.


Right. The SRB hold-down post configuration is not symmetric, either.
Structural considerations will dictate LV placement on the pad, dynamic
considerations will dictate LV flight attitude. The difference between
the two dictates the roll required. Simple as that.
  #15  
Old November 2nd 09, 06:28 PM posted to sci.space.policy,sci.space.shuttle
Me
external usenet poster
 
Posts: 489
Default Ares1-X failure - new information

On Nov 1, 2:37*am, John Doe wrote:
..

But for a symetrically round rocket, why would it need to rotate 90° ?
What does that achieve ? Why not place it in the right orientation on
the pad to begin with if it needs to be in a specific roll orientation ?


Guidance system and Cockpit orientation.

  #16  
Old November 2nd 09, 09:50 PM posted to sci.space.policy,sci.space.history,sci.space.shuttle,alt.politics
Jonathan
external usenet poster
 
Posts: 267
Default ...Ares1-X FAILURE...N KOREA Offers NASA Technical Advice~


"Brian Gaff" wrote in message
...
Yup, its justa few odd bits cobbled together. I suspect the only ral data
they expect to get is that on vibration, and it will be that which dictates
whether its best to carry on or not.


I was listening to some of the astronaut interviews last evening, and reading
between the lines I feel that they all want an upgraded shuttle rather than a
tin can to ride in,



I think this is the direction we should be going...
Small shuttles launched on top of a conventional
booster for now, maybe SSTO down the road.

U.S. Air Force Aims to Launch Space Plane
Next Year
http://www.space.com/news/090602-x-37b-space-plane.html


In any event, it doesn't look like Ares will be helping
keep the ISS fully staffed with US astronauts
any time soon.

Looks like the Russians might be holding the pink slip
on the ISS pretty soon, while we're still making the payments.

s







Brian

--
Brian Gaff....Note, this account does not accept Bcc: email.
graphics are great, but the blind can't hear them
Email:
__________________________________________________ __________________________________________________ __________


"Jeff Findley" wrote in message
...

"Brian Gaff" wrote in message
...
Yes, though not actually seen it, I suspect the following is more truthful..

First test launch of Ares.
Low speed stabilisation needs better algorithm to stop drift and rotation
immediately after launch
Upper stage should be released in a different way to stop spasmodic
afterburning of booster from creating a collision with upper stage
More work on parachute reliability after burn out and clearance of upper
stages needed.

Now maybe all of these things are pretty simple to fix, I don't know, but
surely this means another launch to test they have been fixed?


The next flight, Ares I-Y, is scheduled for March 2014. We'll be waiting
quite a long time and pouring billions of dollars into this program before we
have any real indication that progress is being made. Ares I-X didn't
instill any confidence in the design because it's not representative of
flight hardware.

Jeff
--
"Take heart amid the deepening gloom
that your dog is finally getting enough cheese" - Deteriorata - National
Lampoon





  #17  
Old November 2nd 09, 11:19 PM posted to sci.space.policy,sci.space.shuttle
[email protected]
external usenet poster
 
Posts: 1,516
Default Ares1-X failure - new information

On Nov 2, 12:28�pm, Me wrote:
On Nov 1, 2:37�am, John Doe wrote:
.



But for a symetrically round rocket, why would it need to rotate 90� ?
What does that achieve ? Why not place it in the right orientation on
the pad to begin with if it needs to be in a specific roll orientation ?


Guidance system and Cockpit orientation.


doesnt the shuttle fly a dogleg manuver to avoid overflying land areas
in some cases?
  #18  
Old November 3rd 09, 12:44 AM posted to sci.space.policy,sci.space.shuttle
Brian Thorn[_2_]
external usenet poster
 
Posts: 2,266
Default Ares1-X failure - new information

On Sun, 01 Nov 2009 14:57:46 -0500, John Doe wrote:

Because the pad is fixed - while a vehicle launched from it may depart
on any number of different azimuths. Therefore the vehicle rolls to
align the vehicles various axes with the with the trajectory. This
also helps ensure communications with the vehicle as various antenna
are pointed in the proper direction.


Since this is a round cylinder, why not just place the rocket on the pad
in the right roll orientation to begin with ?


In the case of the lunar missions, that orientation will change as the
Earth/Moon angle changes. So if you have to delay launch a month
because of a glitch or an astronaut is exposed to the measles, you'd
have to roll back to the VAB, destack the vehicle, restack at the new
orientation, and then roll back to the pad. A roll at liftoff just
needs the updated azimuth loaded into software.

So , what is the reason they couldn't orient the rocket on the pad to
remove the need for a 90° roll ?


It would require an all-new SRB design, and Ares I was chosen
specifically to avoid this. (Sure, the SRB is different, but it
fundamentally isn't that different. Its the same diameter with the
same MLP mounts as the Shuttle-version.)

You do know that Titan II (Gemini), Saturn IB (Apollo), and Saturn V
(Apollo) all rolled too, right? Easier to build the pad to be easiest
for ground crews and let the vehicle roll after liftoff, since the
vehicle has to be able to roll for stablization and guidance anyway.

Brian
  #19  
Old November 3rd 09, 07:56 AM posted to sci.space.policy,sci.space.shuttle
BradGuth
external usenet poster
 
Posts: 21,544
Default Ares1-X failure - new information

On Nov 1, 4:05*pm, kT wrote:
John Doe wrote:
Derek Lyons wrote:


Because the pad is fixed - while a vehicle launched from it may depart
on any number of different azimuths. *Therefore the vehicle rolls to
align the vehicles various axes with the with the trajectory. *This
also helps ensure communications with the vehicle as various antenna
are pointed in the proper direction.


Since this is a round cylinder, why not just place the rocket on the pad
in the right roll orientation to begin with ? I realise this may require
some planning, such as ensuring whatever connections to the tower are
placed accordingly (as well as placing the payload (Orion) in such a way
that its door faces the access arm).


So , what is the reason they couldn't orient the rocket on the pad to
remove the need for a 90° roll ?


That's what I do, orient it straight east with the proper roll preset,
and then all you have to deal with is the pitch and the pitch rate.

I like to have pitch, pitch rate, altitude, velocity, acceleration and
elapsed time numerically on my HUD, as well as the usual visual pitch
and momentum vector targets. Of course, with a SINGLE high efficiency
closed combustion cycle regeneratively cooled high performance space
shuttle main engine for propulsion, you have to load the stack up with
payload and use big hydrocarbon boosters in order to prevent exceeding
your acceleration limits, and roll control is a definite problem that
has to be dealt with, otherwise you might indeed spin out of control
after you lose the boosters and really start to haul ass. That's why
there are pairs of outboard ground started OMS engines idling along as
roll control, and ready to do long deep throttling fuel settling and
scavenging burns too, and orbital tweaking and final circularization.

Once you achieve orbit and docking you just react or burn off your
residual fuel to boost the tank farm, and let the space port workers
handle to pesky details of dealing with the tank, payload and engines.

Engine into the nosecone and back to the ocean for quick pickup, and the
tank gets added to your vast orbiting space port and star trek vessels.
Excess fuel quickly burnt off for electricity and heat, and then you
drink and grow plants so that you don't need billion dollar resupply.

Those SRBs are gonna set us back another couple of decades again. Unless
you use them with a decent reusable hydrogen core, they just won't work.

The canceled the Saturn V for a reason, and they didn't even use SRBs.


Saturn V was a Zionist Nazi accomplishment that's still more advanced
and more reliable than anything since, not to mention environmentally
greener.

~ BG
  #20  
Old November 3rd 09, 05:21 PM posted to sci.space.policy,sci.space.shuttle
Robert Clark
external usenet poster
 
Posts: 1,150
Default Ares1-X failure - new information

On Nov 3, 1:56*am, BradGuth wrote:
On Nov 1, 4:05*pm, kT wrote:



John Doe wrote:
Derek Lyons wrote:


Because the pad is fixed - while a vehicle launched from it may depart
on any number of different azimuths. *Therefore the vehicle rolls to
align the vehicles various axes with the with the trajectory. *This
also helps ensure communications with the vehicle as various antenna
are pointed in the proper direction.


Since this is a round cylinder, why not just place the rocket on the pad
in the right roll orientation to begin with ? I realise this may require
some planning, such as ensuring whatever connections to the tower are
placed accordingly (as well as placing the payload (Orion) in such a way
that its door faces the access arm).


So , what is the reason they couldn't orient the rocket on the pad to
remove the need for a 90° roll ?


That's what I do, orient it straight east with the proper roll preset,
and then all you have to deal with is the pitch and the pitch rate.


I like to have pitch, pitch rate, altitude, velocity, acceleration and
elapsed time numerically on my HUD, as well as the usual visual pitch
and momentum vector targets. Of course, with a SINGLE high efficiency
closed combustion cycle regeneratively cooled high performance space
shuttle main engine for propulsion, you have to load the stack up with
payload and use big hydrocarbon boosters in order to prevent exceeding
your acceleration limits, and roll control is a definite problem that
has to be dealt with, otherwise you might indeed spin out of control
after you lose the boosters and really start to haul ass. That's why
there are pairs of outboard ground started OMS engines idling along as
roll control, and ready to do long deep throttling fuel settling and
scavenging burns too, and orbital tweaking and final circularization.


Once you achieve orbit and docking you just react or burn off your
residual fuel to boost the tank farm, and let the space port workers
handle to pesky details of dealing with the tank, payload and engines.


Engine into the nosecone and back to the ocean for quick pickup, and the
tank gets added to your vast orbiting space port and star trek vessels.
Excess fuel quickly burnt off for electricity and heat, and then you
drink and grow plants so that you don't need billion dollar resupply.


Those SRBs are gonna set us back another couple of decades again. Unless
you use them with a decent reusable hydrogen core, they just won't work..


The canceled the Saturn V for a reason, and they didn't even use SRBs.


Saturn V was a Zionist Nazi accomplishment that's still more advanced
and more reliable than anything since, not to mention environmentally
greener.

*~ BG


"Zionist Nazi"

That's quite a combination!

Bob Clark
 




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