It looks like you're using an Ad Blocker.

Please white-list or disable AboveTopSecret.com in your ad-blocking tool.

Thank you.

 

Some features of ATS will be disabled while you continue to use an ad-blocker.

 

Virtual Earth shows Navy Sub Propeller

page: 1
0

log in

join
share:

posted on Sep, 3 2007 @ 03:39 AM
link   
Sorry if this has Already been posted....


The Navy Times reports in a long article dated Aug 19 that a maritime buff, Dan Twohig, found bird's eye view imagery on Microsoft Virtual Earth showing the uncloaked propeller of a US Ohio class submarine in a dry dock. (quote from Ogle Earth) :





Link


Peace....


[edit: title - for accuracy (Virtual)]

[edit on 4-9-2007 by 12m8keall2c]




posted on Sep, 4 2007 @ 07:58 AM
link   
I really cant see much wrong with photographs being taken this close to a naval base. Its not like it shows guard rotations or any security features in place. As for the propellor, they should have had it covered up when in a dry dock if its that secret.

[edit on 4-9-2007 by tronied]



posted on Sep, 9 2007 @ 06:25 AM
link   
Curious here...what can some of you tell about this propeller by the photo??

I dont just mean the number of blades.

Curious about this..what do you guys see here??

And yes..this piece of the propulsion system should be covered up. Someone got slack here. THey are usually covered up even when the dock is flooded. They then remove the cover when the water level in the dock is the same as the river and then the cranes remove the cover off the wheels..or propellors. By this time the whole wheel is underwater.

Some bonehead screwed up here.

Thanks,
Orangetom



posted on Sep, 9 2007 @ 07:17 AM
link   
Mmmm. Maybe they thought "It's OK, we've got until 5 o'clock until that enemy satellite comes over" and forgot about their own.

Yep, someone screwed up..



posted on Sep, 9 2007 @ 07:36 AM
link   

Originally posted by NuclearPaul
Mmmm. Maybe they thought "It's OK, we've got until 5 o'clock until that enemy satellite comes over" and forgot about their own.


lol^

And yeah, this was posted a week or so ago: Virtual Earth image reveals Trident sub's secret propeller



posted on Sep, 9 2007 @ 03:09 PM
link   

Originally posted by orangetom1999
Curious here...what can some of you tell about this propeller by the photo??

I dont just mean the number of blades.



Orangetom

What struck me was the double angle of each blade, making each one look like a Kukri knife in profile. This would increase the surface area of the blade while reducing tip speed in the water, because the total radius of the blade is reduced. This would serve to reduce the shaft speed at which cavitation would occur, i.e. you go faster, quieter.

I would imagine the design to be a compromise of maximum efficiency versus maximum stealth.

Just my thoughts, my degree wasn't in engineering.

[edit on 9-9-2007 by Retseh]



posted on Sep, 10 2007 @ 11:12 AM
link   


This would serve to reduce the shaft speed at which cavitation would occur


I hope you mean increase the shaft speed at which cavitation occurs.

At last a topic i know loads about!!! lol

The basic idea behind the shape of the blade (highly skewed, high blade number, bent shape) have all been around for a good many years. The high skew helps reduce the noise associated with the blade rate, by not having the entire leading edge hit the wake shadow (the effect of the vessel on the inflow velocity of the water) at the same time (this causes the large pressure pulse that is picked up). The high blade count helps keep up efficiency while reducing the size and speed of the prop (the ideal prop would be massive and turning slowly, but this is not proctical as you need massive engines to power it, and deep water). The kink in the blades is a design feature that again helps to reduce the noise while maintaining efficiency.

As has been said on here, the technology has moved on and most modern western subs now use a pump jet propulsor rather than a traditional prop.



posted on Sep, 15 2007 @ 06:36 PM
link   

Originally posted by paperplane_uk
I hope you mean increase the shaft speed at which cavitation occurs.



Quite right.



posted on Sep, 15 2007 @ 07:08 PM
link   
Some of the newer props used in general aviation are designed the same way. The curve in the blade allows more surface area to be used in the same diameter. In propeller driven airplanes most of the noise from the blade is made at the tips. Curving the blade reduces the noise and may also increase the overall performance. I would assume that a propeller used in water would work in a similar fasion.




top topics



 
0

log in

join