Old Salt
Posts: 489
Location: San Freakcisco CA area | Subject: RE: USS SILVERSIDES
Jon - I can answer your question only with regard to PAMPANITO; however, from what I understand, the basic Navy requirements apply to all museum boats. PAMPANITO's screws were removed before she was turned over to the SFMNPA for museum boat duty. If my understanding is correct, this applies to museum boats in general but I won't swear to that.
As a kid growing up in Chicago, I often played hooky from Our Lady of Perpetual Guilt to visit SILVERSIDES at Navy Pier. At that time there was a USNR contingent aboard and there was a DE tied up astern - FRAMINGTON or FRAMINGHAM or somesuch. Anyway, what I was told is that in order to be brought into the Great Lakes, both ships had to have their screws removed. Whether that was a sea bat type story I don't know, but I do remember seeing tugs being used to move the ships around from time to time.
Three of PAMPANITO's four main FM-38D 8-1/8X10 engines as well as the FM-35A 5-1/4X7 dinky run. All 252 battery cells have been removed, thus there is no normal source of DC aboard except directly from the generators. So we installed a rectifier system to provide 250VDC in order to power various motors, ICMGs, and ventilation blowers from AC shore power.
The main generators are locked out electrically, but the dinky generator is self-exciting so we really have to be careful about not inadvertantly paralleling up with the DC bus (read: huge fireballs!) from a generator whenever we run an engine.
The propulsion bus links were also pulled in order to prevent inadvertant paralleling of ship's DC with the rectifier supply and also to prevent overloading the rectifiers and shore power cable by someone operating the propulsion cubicle.
You can make it idiot-proof but you can't make it visitor-proof!
As an aside comment, whenever we line up to run an engine or need a ventilation blower during our monthly PAMPANITO Breakfasts, we have to go thru the entire boat to make sure no DC motors are turned on that we don't need -- visitors will punch every button they can find so our answer is to keep the DC auxiliary power bus aft and crosstie to DC aux power forward locked off until we need a fuel or lube oil pump or a ventilation blower. The motor controllers are all the direct connect type - i.e. they are either on or off and do not default to off whenever the DC bus is dead so if someone punched an on button, the motor will start when the aux power bus is activated.
Anyway, to answer your question, by replacing the propulsion bus links, it would be possible to turn the propulsion motors and shafts using generator power.
PAMPANITO still has her 1945 configuration high speed motors and reduction gear drive to the shafts. That introduces a whole new level of maintenance requirements, lube oil, cooling water, etc. that isn't easy to do in a museum boat environment (takes $$$ and knowledgeable manpower) so as far as I know, we've never spun a shaft on generator power since the boat was turned over to the Association - or whether that ever happened during her post-war career as a dockside trainer at Mare Island for that matter.
So the short answer is technically, it is possible to turn PAMPANITO's shafts but practically speaking, the answer is no. Plus, not knowing the condition of the shaft seals ( 1945 vintage lignum vitae) I'd sure as hell be afraid of damaging them and creating a Motor Room leakage problem that we don't have at the moment! 
Edited by SOB490 2008-10-24 7:48 AM
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