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