AC & DC power sources in Apollo spacecraft

I'm a little confused here. Did Apollo spacecraft use both AC and DC
power? If so, why? What about the LM?

I've also read a few histories of the Apollo 13 accident and was
wondering just how was the LM able to charge the CM's reentry
batteries? Was there a hard-wire connection between the two
spacecraft, or was this process another "jury-rigged" procedure like
adapting the carbon dioxide scrubbers??

Thanks, Dave

In article .com,
DaveDeWolfe wrote:
I'm a little confused here. Did Apollo spacecraft use both AC and DC
power? If so, why? What about the LM?

As rk has already posted, yes, there was AC power aboard, for motors.
It's just a whole lot easier to make good, reliable, efficient motors
if you can drive them with AC. Yes, the LM too.

I've also read a few histories of the Apollo 13 accident and was
wondering just how was the LM able to charge the CM's reentry
batteries? Was there a hard-wire connection between the two
spacecraft...

There was a hand-connected umbilical in the pressurized tunnel between
the two. It was meant for charging the LM's batteries from the CSM, and
some improvising had to be done to send power the other way, but the
hardware was already in place.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

On Mon, 3 Jan 2005 17:58:44 GMT, (Henry Spencer)
wrote:

There was a hand-connected umbilical in the pressurized tunnel between
the two. It was meant for charging the LM's batteries from the CSM, and
some improvising had to be done to send power the other way, but the
hardware was already in place.

....This begs explanation. Has NASA or any of the "Tiger Team" ever
given the full details on how the CSM/LM stack was reconfigured in
flight to allow the current to go the other way?

OM

--

"No ******* ever won a war by dying for | http://www.io.com/~o_m
his country. He won it by making the other | Sergeant-At-Arms
poor dumb ******* die for his country." | Human O-Ring Society

- General George S. Patton, Jr

"OM" om@our_blessed_lady_mary_of_the_holy_NASA_researc h_facility.org wrote
in message news
On Mon, 3 Jan 2005 17:58:44 GMT, (Henry Spencer)
wrote:

There was a hand-connected umbilical in the pressurized tunnel between
the two. It was meant for charging the LM's batteries from the CSM, and
some improvising had to be done to send power the other way, but the
hardware was already in place.

...This begs explanation. Has NASA or any of the "Tiger Team" ever
given the full details on how the CSM/LM stack was reconfigured in
flight to allow the current to go the other way?

OM

.... and as an additional question .. in the post Apollo 13 configurations
(e.g., extra large battery in SM) were these interfaces modified for ease of
bi-directional charging?

gb

"OM" om@our_blessed_lady_mary_of_the_holy_NASA_researc h_facility.org wrote
in message news
On Mon, 3 Jan 2005 17:58:44 GMT, (Henry Spencer)
wrote:

There was a hand-connected umbilical in the pressurized tunnel between
the two. It was meant for charging the LM's batteries from the CSM, and
some improvising had to be done to send power the other way, but the
hardware was already in place.

...This begs explanation. Has NASA or any of the "Tiger Team" ever
given the full details on how the CSM/LM stack was reconfigured in
flight to allow the current to go the other way?


Easy, rather than pointing the LM down so the electricity flows downhill,
they put it on top so it would flow the other way.


OM

--

"No ******* ever won a war by dying for | http://www.io.com/~o_m
his country. He won it by making the other | Sergeant-At-Arms
poor dumb ******* die for his country." | Human O-Ring Society

- General George S. Patton, Jr

On Tue, 04 Jan 2005 00:32:07 GMT, "Greg D. Moore \(Strider\)"
wrote:

Easy, rather than pointing the LM down so the electricity flows downhill,
they put it on top so it would flow the other way.

....Someone give me a good reason why I shouldn't plonk Greg back into
Killfile Hell, please?

OM

--

"No ******* ever won a war by dying for | http://www.io.com/~o_m
his country. He won it by making the other | Sergeant-At-Arms
poor dumb ******* die for his country." | Human O-Ring Society

- General George S. Patton, Jr

OM om@our_blessed_lady_mary_of_the_holy_NASA_researc h_facility.org writes:

On Tue, 04 Jan 2005 00:32:07 GMT, "Greg D. Moore \(Strider\)"
wrote:

Easy, rather than pointing the LM down so the electricity flows downhill,
they put it on top so it would flow the other way.

...Someone give me a good reason why I shouldn't plonk Greg back into
Killfile Hell, please?

Because sometimes he has a sense of humor? Hey, I thought it was funny.

And you (and others) have never learned "Please Do Not Feed The Troll"

It's far far better to silently plonk them and ignore them, than to give them
the attention they're whoring for. Lots of sad people live for the sound of a
"plonk", it's kind of like S&M, and it's usually the only attention they can
get.

I have an "anti-kill" file, it marks posts by certain people such as Henry or
Mary in bold as important, with a key I can hit to go directly to the next
one.

After that, I'll usually read the associated thread if it sounds interesting
from what Henry quoted. I figure if Henry thought it worth participating, it's
worth reading. I then just hit "mark all as read", and that's about it.

I can also mark certain subjects as interesting.

Of course hpywife-whatever, Bob Haller, etc, are in permanent killfile
hell. And all my sci.space.* killfiles are linked, so a plonk in one group
works for all.

Makes life much more bearable.

-gc

--
Christmas is weird. What other time of the year do you sit in front of
a dead tree and eat candy out of your socks?
-- (alt.gothic)

OM (om@our_blessed_lady_mary_of_the_holy_NASA_researc h_facility.org) writes:
On Tue, 04 Jan 2005 00:32:07 GMT, "Greg D. Moore \(Strider\)"
wrote:

Easy, rather than pointing the LM down so the electricity flows downhill,
they put it on top so it would flow the other way.

...Someone give me a good reason why I shouldn't plonk Greg back into
Killfile Hell, please?

Because that was funny. g

Andre
--
" I'm a man... But, I can change... If I have to... I guess. "
The Man Prayer, Red Green.

Greg D. Moore (Strider) wrote:

Easy, rather than pointing the LM down so the electricity flows downhill,
they put it on top so it would flow the other way.


Where's that damn hook when you need it? :-)

Pat

In article ,
OM om@our_blessed_lady_mary_of_the_holy_NASA_researc h_facility.org wrote:
...It was meant for charging the LM's batteries from the CSM, and
some improvising had to be done to send power the other way, but the
hardware was already in place.

...This begs explanation. Has NASA or any of the "Tiger Team" ever
given the full details on how the CSM/LM stack was reconfigured in
flight to allow the current to go the other way?

If memory serves, it was reportedly necessary to start with the CM
charging the LM, and then fiddle with details to reverse the flow.
But I've never seen further detail. Must read the paper rk turned up...
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |