Apollo rendezvouses

I've been looking at some of the Apollo lunar rendezvous footage on
Youtube, and was curious about a couple of things ...

1) the LM was the active partner in the final docking, wasn't it? Was the
CDR or the PLT doing the docking? And at what point did the CSM enter free
drift?

2) the clips I've seen do not have any exhaust from the LM visible from the
CSM -- in the original film, was there any visible exhaust?

/dps

On 29/09/2011 5:01 PM, Snidely wrote:
I've been looking at some of the Apollo lunar rendezvous footage on
Youtube, and was curious about a couple of things ...

1) the LM was the active partner in the final docking, wasn't it? Was the
CDR or the PLT doing the docking? And at what point did the CSM enter free
drift?

2) the clips I've seen do not have any exhaust from the LM visible from the
CSM -- in the original film, was there any visible exhaust?

/dps



CSM was the active partnter in rendezvous and docking.

On 09/29/2011 02:01 AM, Snidely wrote:
I've been looking at some of the Apollo lunar rendezvous footage on
Youtube, and was curious about a couple of things ...

1) the LM was the active partner in the final docking, wasn't it? Was the
CDR or the PLT doing the docking? And at what point did the CSM enter free
drift?

LM was active during rendezvous and braking phase until stationkeeping
at 50 ft. Then pitched down and aligned for docking, then CSM was active
for final approach and docking. CSM entered free drift post-capture.

2) the clips I've seen do not have any exhaust from the LM visible from the
CSM -- in the original film, was there any visible exhaust?

Not in any I've seen.

" LM was active during rendezvous and braking phase until stationkeeping
at 50 ft. Then pitched down and aligned for docking, then CSM was active
for final approach and docking. CSM entered free drift post-capture.

The LM CDR would have had to perform the docking while looking "up" thru a
small docking window. This was shown to be feasible which allowed the LM
designers to delete docking capability via the forward door - a significant
weight savings. Feasible but a bit awkward.

2) the clips I've seen do not have any exhaust from the LM visible from
the
CSM -- in the original film, was there any visible exhaust?

Not in any I've seen.

The LM Ascent Propulsion and RCS used the same hypergolics, Fuel and
Oxidizer could be cross fed betwen the two subsystems. No visible exhaust -
reference the Lunar lift-off Videos.


Val Kraut

"Val Kraut" scribbled something like ...


" LM was active during rendezvous and braking phase until
stationkeeping
at 50 ft. Then pitched down and aligned for docking, then CSM was
active for final approach and docking. CSM entered free drift
post-capture.

The LM CDR would have had to perform the docking while looking "up"
thru a small docking window. This was shown to be feasible which
allowed the LM designers to delete docking capability via the forward
door - a significant weight savings. Feasible but a bit awkward.


Oooh, interesting. And there's a nice clip out there of docking with the
LM on the outbound leg. (I found the one that didn't have music added
.... but it does have the earth-side audio, with Houston "calling blind"
until the hi-gain antenna gets locked on.)


(And yes, I used PLT when I meant LMP, but I know now to use CMP for the
final 50 ft.)

2) the clips I've seen do not have any exhaust from the LM visible
from the
CSM -- in the original film, was there any visible exhaust?

Not in any I've seen.

The LM Ascent Propulsion and RCS used the same hypergolics, Fuel and
Oxidizer could be cross fed betwen the two subsystems. No visible
exhaust - reference the Lunar lift-off Videos.


/dps

"Val Kraut" wrote in message
...

" LM was active during rendezvous and braking phase until stationkeeping
at 50 ft. Then pitched down and aligned for docking, then CSM was active
for final approach and docking. CSM entered free drift post-capture.

The LM CDR would have had to perform the docking while looking "up" thru a
small docking window. This was shown to be feasible which allowed the LM
designers to delete docking capability via the forward door - a
significant weight savings. Feasible but a bit awkward.


As FTETTM put it: "Astronauts are smart. They'll figure it out!"
--
Gordon Davie
Edinburgh, Scotland

"Slipped the surly bonds of Earth...to touch the face of God."

Snidely scribbled something like ...

Oooh, interesting. And there's a nice clip out there of docking with
the LM on the outbound leg.

In another nice clip, the camera is being used for shots of interior
activities, including when the astronaut holds the cellphone out at arms
length and aims at himself.

Oops, mechanical camera, not cellphone.

/dps

"Val Kraut" scribbled something like ...

[quoting Jorge]
" LM was active during rendezvous and braking phase until
stationkeeping
at 50 ft. Then pitched down and aligned for docking, then CSM was
active for final approach and docking. CSM entered free drift
post-capture.

So the LM was in free drift after getting into position, yesno?


The LM CDR would have had to perform the docking while looking "up"
thru a small docking window.

The CMP may have a bigger window, but it's off-center, so he's aiming for
that odd strap thing as his target?

/dps

On 09/30/2011 12:54 PM, Snidely wrote:
"Val scribbled something like ...

[quoting Jorge]
" LM was active during rendezvous and braking phase until
stationkeeping
at 50 ft. Then pitched down and aligned for docking, then CSM was
active for final approach and docking. CSM entered free drift
post-capture.

So the LM was in free drift after getting into position, yesno?

The LM stayed in attitude hold until capture, then the CDR manually
commanded free drift. I'd have to dig out the procedures to find the
exact sequence.

The LM CDR would have had to perform the docking while looking "up"
thru a small docking window.

The CMP may have a bigger window, but it's off-center, so he's aiming for
that odd strap thing as his target?

Both windows were off-center. The CMP's COAS was boresighted on a
docking target fixed to the roof of the LM. The CDR's COAS was
boresighted on a docking target installed in the CM starboard rendezvous
window by the CMP.

"Jorge R. Frank" patiently scribbled something ...

Thanks again.

/dps