Is htv risky?

"Jeff Findley" wrote in message
...

An even better example might be in air refueling. The human workload
there is pretty high. You've got at least two pilots and a boom operator
who all have to be "on their toes" during the entire operation. That's a
really hard task to automate. I'm not sure if it's ever been done in an
automated or teleoperated fashion. I wonder if the USAF has experimented
with in air refueling of UAV's...

Looks like this has been done as a research program:

http://www.air-attack.com/news/news_...apability.html

Makes me wonder how much work is left before this sort of capability could
be deployed in the field. Imagine UAV's that only have to land for
maintenance. Cool.

Jeff
--
"Many things that were acceptable in 1958 are no longer acceptable today.
My own standards have changed too." -- Freeman Dyson

Jorge R. Frank wrote:

HTV was never baselined for Node 3. It will be berthed at Node 2 nadir -
just like it has always been planned to be.

Would Shuttle be allowed to dock on node2 while HTV is at node2 nadir ?
I take it that if "yes", it would however prevent the shuttle from
delivering an MPLM or any other module since HTV would not provide any
clearance to get stuff out of the cargo bay ?

(I realise that this is now moot since it is ulikely the shuttle will be
flying by the time HTV materialises)

On Dec 8, 4:43*pm, "Jeff Findley" wrote:

Lost, but perhaps not for long. *Space-X's Dragon plans to use CBM's and
should provide something like 7 to 10 cubic meters of cargo return
capability.


Notice that I mentioned ATV and Dragon in the same sentence and then
connected them both to the ability to move large cargo via the CBMs.
While Dragon can return cargo, it's not on the same level as STS/
MPLM.
-Mike

On Mon, 08 Dec 2008 23:01:44 -0600, "Jorge R. Frank"
wrote:

Probably Node 1 nadir now that Node 3 won't be there (Node 3 is now
baselined for Node 1 port, opposite Quest).

HTV was never baselined for Node 3. It will be berthed at Node 2 nadir -
just like it has always been planned to be.

Has that been reconsidered and reapproved since 107? I'd think NASA
would have a bit of the butterflies letting HTV loiter that close to
an Orion parked at Node 2, which will always be the case once Orion
starts flying.

Brian

Brian Thorn wrote in
news
On Mon, 08 Dec 2008 23:01:44 -0600, "Jorge R. Frank"
wrote:

Probably Node 1 nadir now that Node 3 won't be there (Node 3 is now
baselined for Node 1 port, opposite Quest).

HTV was never baselined for Node 3. It will be berthed at Node 2 nadir -
just like it has always been planned to be.

Has that been reconsidered and reapproved since 107? I'd think NASA
would have a bit of the butterflies letting HTV loiter that close to
an Orion parked at Node 2, which will always be the case once Orion
starts flying.

Regardless of where the HTV gets berthed, the capture box is in the same
location - under the JEM PM, because that's where the retroreflectors are.
Then the SSRMS captures the HTV and maneuvers it from the capture box to
the berthing location.

Berthing HTV to Node 2 nadir therefore incurs no higher risk to the Orion
than any other location, since HTV wouldn't be "hovering" near the Orion,
but rather would be under control of the SSRMS by then.

Jorge R. Frank wrote:

Regardless of where the HTV gets berthed, the capture box is in the same
location - under the JEM PM, because that's where the retroreflectors are.
Then the SSRMS captures the HTV and maneuvers it from the capture box to
the berthing location.


Is it physically possible for the arm to capture HTV under node2, and
move it under the truss to node-1 ? Which PDGF on the station would
allow such a movemenbt with adequate reach without the truss impeding
the movement ?

wrote in message
...
On Dec 8, 4:43 pm, "Jeff Findley" wrote:

Lost, but perhaps not for long. Space-X's Dragon plans to use CBM's and
should provide something like 7 to 10 cubic meters of cargo return
capability.


Notice that I mentioned ATV and Dragon in the same sentence and then
connected them both to the ability to move large cargo via the CBMs.
While Dragon can return cargo, it's not on the same level as STS/
MPLM.

True, but my argument is that it is a desire to return an entire experiment
rack to the earth more so than a hard requiremnet. What scientists on the
ground want is their results back. Sometimes results can be sent back as
digital data via radio wave, which costs zero downmass. Other times results
can be sent back as material/biological/whatever samples which are the true
end result of the experiment.

While Dragon will not fill the desire to return all used experiment racks to
earth, it will do a much better job at the requirement of returning
experimental results to earth.

ATV, HTV, and Progress can be used to remove garbage from ISS, and HTV does
have a CBM on it, so it can be used to dispose of entire experiment racks.
The US side of ISS need not suffer the same problems that Mir had with large
amounts of broken equipment sitting around in modules simply because of
hatch size limitations, Progress limitations, and the like.

Jeff
--
"Many things that were acceptable in 1958 are no longer acceptable today.
My own standards have changed too." -- Freeman Dyson

Jeff Findley wrote:

True, but my argument is that it is a desire to return an entire experiment
rack to the earth more so than a hard requiremnet.


The whole point of developping the ability to return racks was to enable
experiments that would have required the rack be returned. Just because
they haven't yet scheduled such experiments doesn't mean that the need
wouldn't have become "hard requirement" later on. And remember that some
experiments may have devices that are too big to fit through the russian
hatches, so they couldn't be disposed of.



Remember that while so far, "experiment" has been a term associated with
watching crystals grow in a test tube, the real experiments in the
station are getting systems to work reliably. Didn't the russians hitch
a ride on a shuttle to return a failed Elektron unit after a replacement
had been sent by Progress ?


If you have a failed unit, and you are required to disassemble it to fit
in a return vehicle, then the act of disassembling it might disrupt the
conditions and skew any analysis done on earth when the unit is examined .


BTW, JAXA has a few pages in english for HTV:

http://iss.jaxa.jp/en/htv/operation/

It mentions first launch in 2009. But the rocked is still under
development. Anyone hae some background on the readyness of that rocket ?

Often, such web sites were built many years ago and not really updated
with new schedules.

"John Doe" wrote in message
...
Jeff Findley wrote:

True, but my argument is that it is a desire to return an entire
experiment
rack to the earth more so than a hard requiremnet.


The whole point of developping the ability to return racks was to enable
experiments that would have required the rack be returned. Just because
they haven't yet scheduled such experiments doesn't mean that the need
wouldn't have become "hard requirement" later on.

In other words, this was a capability in search of a requirement.

Because the shuttle and MPLM's (or something like them) were assumed to be
available until the end of the life of ISS, the ability to return entire ISS
racks to earth was a no brainer to implement. However, this assumption has
changed, so it's time to re-evaluate whether this was really a hard
requirement or just a desire.

I have this sort of argument with our "product marketing" people all the
time when I'm told to implment some bit of functionality. If I don't know
of any customer who needs this functionality, I'll tell them, show me a real
customer/user workflow that requires this functionality.

I'm not going to spend weeks, months, or even years developing new
functionality without a real customer workflow. In years past when we've
implemented such capability without a real user workflow, all we've ended up
with is unused functionality which doesn't make the company money.

And remember that some
experiments may have devices that are too big to fit through the russian
hatches, so they couldn't be disposed of.

Again, HTV will take care of disposal. Disposal of hardware is a
requirement which is separate from returning mass to earth. Shuttle/MPLM is
a solution to both problems, but that does NOT mean that the same vehicle
has to do both requirements simultaneously.

Remember that while so far, "experiment" has been a term associated with
watching crystals grow in a test tube, the real experiments in the
station are getting systems to work reliably. Didn't the russians hitch
a ride on a shuttle to return a failed Elektron unit after a replacement
had been sent by Progress ?

True, because they wanted it back on earth for failure analysis and repair
since Elektron's are rare hardware. Such a requirement could be fulfilled
by Space-X's Dragon.

But not every bit of failed hardware has to be returned to earth. A failed
laptop on ISS is arguably far cheaper to replace with a new one than it is
to return the failed one and refurbish it. It would also be foolish to
require that every failed light bulb be returned to earth. You might want a
couple returned for failure analysis, but that's about it.

If you have a failed unit, and you are required to disassemble it to fit
in a return vehicle, then the act of disassembling it might disrupt the
conditions and skew any analysis done on earth when the unit is examined .

Then NASA had better hope that Dragon works and is available soon, hadn't
they?

BTW, JAXA has a few pages in english for HTV:

http://iss.jaxa.jp/en/htv/operation/

It mentions first launch in 2009. But the rocked is still under
development. Anyone hae some background on the readyness of that rocket ?

Often, such web sites were built many years ago and not really updated
with new schedules.

I'm not sure what the current schedule is. Even NASA websites are sometimes
bad about updating such information. The Mitsubishi website says first
launch in 2008. :-P

That said, you'd think that JAXA would want to get it flying sometime soon,
considering that the JEM is now in orbit. When ISS is expanded to a six
person crew, I'd think that they'd want HTV flying a.s.a.p. :-)

Jeff
--
"Many things that were acceptable in 1958 are no longer acceptable today.
My own standards have changed too." -- Freeman Dyson

hello,

somebody have news from HTV or HIIB ?

link or blog ?

i have nothing news since 08/2008, from jaxa

http://fr.youtube.com/watch?v=wqAWYKMA9R8

Thanks