Spacewalkers Install New
Camera Assembly, Jettison FPP
Space station Commander and NASA Science Officer Bill McArthur
and Flight Engineer Valery Tokarev installed a new camera assembly
and jettisoned the Floating Potential Probe during a 5-hour, 22
minute spacewalk Monday.
McArthur, designated EV1 (for Extravehicular Activity) and wearing
the spacesuit with red stripes, and Tokarev, EV2, in the all-white
suit, also completed two get-ahead tasks.
The camera assembly installation on the Port 1 Truss was the first
of the two primary tasks. The new device is similar to the camera
assembly on the Starboard 1 Truss, and was installed on a P1 lower
outboard stanchion. It will have a big role in future station
The camera assembly will be used after arrival of the P3 and P4
truss segment during STS-115, station assembly flight 12A, next
year. It will offer visual perspective to arm operator Steve MacLean,
a Canadian astronaut, as he maneuvers the truss segment for installation.
The truss segment brings with it another radiator and another
set of solar wings. Stretching 240 feet from tip to tip, the solar
assembly will almost double the total electricity generating capacity
of the station.
McArthur and Tokarev spent about 2 hours, 10 minutes on the camera
assembly installation. In order to have daylight for the Floating
Potential Probe jettison, they moved on to one of the get-ahead
tasks, the retrieval of a failed remote joint motor controller.
Engineers are anxious to get this one back to see what went wrong
before others are sent to the space station.
After taking the RJMC and tools from the first task back to the
airlock, they then moved, with McArthur in the lead, up the P6
truss to the Floating Potential Probe.
The FPP was situated atop the P6 Truss between the station's solar
wings. It was designed to measure the station's electrical potential
and compare it to the surrounding plasma. It wasn't working.
Photos showed FPP fasteners had backed out. That raised concerns
that the fasteners could become detached and perhaps cause damage.
McArthur and Tokarev released and stowed a grounding wire, then
released the FPP housing from its stanchion. They checked its
condition and then report lighting conditions to Houston with
an eye to jettisoning the FPP.