Spacecraft Health, A cause for concern? Options

[jasedm]

I generally read most of the significant events (S.E) reports that are posted on the Cassini-Huygens website, and the spacecraft is always described as being in excellent health and operating normally.
The reason for this post is that the latest S.E report see here states:

"AACS is continuing to investigate the significant change in RWA-2 friction test results. This has not affected any overall pointing or other spacecraft performance to date"

As I understand it, there are four RWA (reaction wheel assemblies) which control attitude and pointing when thrusters are not used. Three of the RWA's are used at any one time. RWA-3 was switched to RWA-4 in July 2003 after problems with 'oscillations' leaving three usable RWA's.
If RWA-2 is also experiencing problems, is this a cause for concern re: future spacecraft science, as a failure would result in having to use the reaction control subsystem (i.e thrusters), with subsequent loss of some pointing/stabilisation accuracy, and the much-increased depletion of consumables.

On the first day of the extended mission, should we be:

1) Concerned like hell for some of the XM science
2) A little concerned, consumable use may rule out an XXM in the event of RWA-2 failing, but the XM is safe
3) A little worried, but the problem can be worked around with other in-built subsystem redundancy
3) Not worried at all - Jase should stop being a panic-merchant and lie down in a darkened room with a beer and some soothing music

[nprev]

Don't think it's too scary yet. If they lose another RWA, I presume that would mean that they'd have to augment maneuvers with the thrusters, but only along one plane; not nearly as bad in terms of propellant consumption as having to use the RCS for all attitude positioning.

I was sort of amazed to learn from that update that the main engine cover has completed 40 cycles since launch. That is really impressive for a moving part that's been directly exposed to space for twelve years!

[Del Palmer]

3) Not worried at all - Jase should stop being a panic-merchant and lie down in a darkened room with a beer and some soothing music

That sounds like a great option, regardless of the outcome!

[PDP8E]

Cassini plasma spectrometer is working again after nine months off line.
details...
http://news.yahoo.com/instrument-cassini-c...-204927160.html