IU

A friend gave me the Haynes manual for Xmas, and in reading it [&
looking at the pictures...] I've realized I know diddly about the IU,
besides IBM made it.

I know it saved the bacon when lighting hit the launching stack, but
for example, how did it navigate? I see it had its own radar; I'm
guessing it interrogated ground transponders that let it calculate its
position to compare with the INS. Correct?



--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

David Lesher wrote:
A friend gave me the Haynes manual for Xmas, and in reading it [&
looking at the pictures...] I've realized I know diddly about the IU,
besides IBM made it.

I know it saved the bacon when lighting hit the launching stack, but
for example, how did it navigate? I see it had its own radar; I'm
guessing it interrogated ground transponders that let it calculate its
position to compare with the INS. Correct?

Not correct. It had an inertial platform (ST-124) and used inertial
navigation. There was no "external" source of position; the LVDC
computed position and velocity by integrating the acceleration from the
ST-124.

Jorge R. Frank wrote:
David Lesher wrote:
A friend gave me the Haynes manual for Xmas, and in reading it [&
looking at the pictures...] I've realized I know diddly about the IU,
besides IBM made it.

I know it saved the bacon when lighting hit the launching stack, but
for example, how did it navigate? I see it had its own radar; I'm
guessing it interrogated ground transponders that let it calculate its
position to compare with the INS. Correct?

Not correct. It had an inertial platform (ST-124) and used inertial
navigation. There was no "external" source of position; the LVDC
computed position and velocity by integrating the acceleration from the
ST-124.

I'll add (of course) that the ground did perform tracking of the S-V and
could uplink a new state vector to the IU if the inertial navigation
system got too far off.

"Jorge R. Frank" writes:

I know it saved the bacon when lighting hit the launching stack, but
for example, how did it navigate? I see it had its own radar; I'm
guessing it interrogated ground transponders that let it calculate its
position to compare with the INS. Correct?

Not correct. It had an inertial platform (ST-124) and used inertial
navigation. There was no "external" source of position; the LVDC
computed position and velocity by integrating the acceleration from the
ST-124.

I'll add (of course) that the ground did perform tracking of the S-V and
could uplink a new state vector to the IU if the inertial navigation
system got too far off.

So what did it use the radar for?


--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

David Lesher wrote:
"Jorge R. Frank" writes:

I know it saved the bacon when lighting hit the launching stack, but
for example, how did it navigate? I see it had its own radar; I'm
guessing it interrogated ground transponders that let it calculate its
position to compare with the INS. Correct?
Not correct. It had an inertial platform (ST-124) and used inertial
navigation. There was no "external" source of position; the LVDC
computed position and velocity by integrating the acceleration from the
ST-124.

I'll add (of course) that the ground did perform tracking of the S-V and
could uplink a new state vector to the IU if the inertial navigation
system got too far off.

So what did it use the radar for?

Depends on what you mean by "it". The Saturn V did not have radar. The
LM did (both a rendezvous radar and a landing radar), but of course
these could not be used during launch since the LM was stowed in the SLA
and powered down.

"Jorge R. Frank" writes:


Depends on what you mean by "it". The Saturn V did not have
radar. The LM did (both a rendezvous radar and a landing
radar), but of course these could not be used during launch
since the LM was stowed in the SLA and powered down.

I knwo of those two; but picture MSFC 68-IND-1200-24 A
as seen on page 55 of Haynes shows "C band Radar" in the
IU, next to the air supply tank.

--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

On Feb 24, 4:20*am, David Lesher wrote:
"Jorge R. Frank" writes:

Depends on what you mean by "it". The Saturn V did not have
radar. The LM did (both a rendezvous radar and a landing
radar), but of course these could not be used during launch
since the LM was stowed in the SLA and powered down.

I knwo of those two; but picture MSFC 68-IND-1200-24 A
as seen on page 55 of Haynes shows "C band Radar" in the
IU, next to the air supply tank.


That is the transponder for the Range C band Radars

Me writes:

I know of those two; but picture MSFC 68-IND-1200-24 A
as seen on page 55 of Haynes shows "C band Radar" in the
IU, next to the air supply tank.


That is the transponder for the Range C band Radars

Ground-based tracking radar? That would make lots of sense to
me; I didn't understand why the heavy part wouldn't be on the
ground.

I assume there were 3+ sites so they could triangulate
the position.


--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

David Lesher wrote:
I assume there were 3+ sites so they could triangulate the position.

I suppose it would help, but assuming one had the angles (say off the
radar antenna on the ground - how left/right, how up/down) and the
distance (how long for the radar pulse to return) one could make a
decent first order aproximation.

rick jones
--
I don't interest myself in "why". I think more often in terms of
"when", sometimes "where"; always "how much." - Joubert
these opinions are mine, all mine; HP might not want them anyway...
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...

On Feb 24, 6:41*pm, David Lesher wrote:
Me writes:
I know of those two; but picture MSFC 68-IND-1200-24 A
as seen on page 55 of Haynes shows "C band Radar" in the
IU, next to the air supply tank.

That is the transponder for the Range C band Radars

Ground-based tracking radar? That would make lots of sense to
me; I didn't understand why the heavy part wouldn't be on the
ground.

I assume there were 3+ sites so they could triangulate
the position.

Nope, just two, prime and backup. Radars don't requiret multiple
sites, only one is required.