Basically, they show a submarine’s tower breaching the ice, then a truck drives into the shot, apparently within a few dozen yards of the sub*.
Is/could this segment be real? Could you really drive a truck up next to a sub* that’s just broken through (apparently) foot-thick ice? Or is this just clever green-screening or CGI?
Also, as a side note, do the dive planes on a sub’s tower really rotate to fully vertical around a central pivot/axle?
*technically, just the sub’s tower, which is the only part showing above the ice.
Of course it is CGI. The U.S. Navy isn’t going to send a submarine to the Arctic for a car commerical; for that matter, GMC isn’t about to send a camera crew, truck, and actors to the Arctic, either.
Yes, subs with tower mounted dive planes do rotate to vertical to breach the ice. The have to rotate in general, or otherwise they wouldn’t make very good dive planes
That was the biggest surprise to me; I had no idea that dive planes (and I didn’t know that’s what they’re called) rotated at all, let alone to vertical. I always assumed they were fixed.
First off, note that the submarine “tower” (formerly known as a conning tower) is now referred to as a “sail.”
Secondly, only older submarines (such as the Sturgeon-class and Permit-class) had fairwater planes that could be rotated to vertical to facilitate under-ice surfacing.
The first 40 or so Los Angeles-class submarines had fairwater planes that could not be rotated to vertical. They also did not not have hardened sails, so the combination of these two factors made it such that the original Los Angeles-class subs were not really under-ice capable.
Newer improved Los-Angeles-class submarines (688I) hardened the sail and moved the fairwater planes off of the sail entirely and up to the bow, and the newer submarine classes (Seawolf-class and Virginia-class) have followed suit.
So the short answer is that the commercial is clearly that of a very old submarine surfacing. The last of the Sturgeon-class submarines were decommissioned over a decade ago, so the shot is not real; it’s CGI.
As for whether you could walk or drive next to a submarine after it has surfaced through polar ice, generally yes, that would be no issue. Typical ice thicknesses are 3-4 feet thick, and this will easily support a vehicle.
It is vital that dive planes can move. They work just like the control surfaces on an airplane.
While submarines can adjust their buoyancy by adjusting the amount of water in their variable ballast tanks, moment-to-moment depth control is done by means of dive planes.
Actually, the forward planes (fairwater planes on the sail or bow planes up forward) are really for fine control. The main control planes are the stern planes.
Finally, the other main control surface is the large rudder back aft.
It’s pretty close, though in the commercial the planes rotate back to horizontal once they’ve breached. That’s not shown in the real video, and seems counterproductive. You would want them in the vertical position when you dived again.
Didn’t a sub do this in an X-Files episode, complete with the vertical dive planes? My first reaction the first time I saw this commercial was a very David-Duchovny-heavy sense of deja vu.
Good point. I wonder how long the rotation actually takes in reality. I suppose a sub wouldn’t bother surfacing for only a few minutes, so it makes sense for them to reconfigure for surface conditions. And for the polar bear watch :).
Well now that the general question has been answered I got some more:
Do they blow the ballasts well bellow the ice so the are surfacing at ‘ramming speed’? Is it a more gradual constant pressure until the ice breaks?
Any instances of serious damage from surfacing under ice? Do they avoid doing this or is a a routine drill?
How much data does a modern submarine have on the ice before they attempt to surface? How is their data established? Expedition records? Weather reports? Drill bit on the para-scope?
Could they try to surface and learn it’s too thick for them to breach and go looking for a softer spot? Is all the data known and they only attempt to breach in the defined parameters?
I was surprised that the whole thing rotated. I’d have thought just a portion of it would rotate, with a fixed portion that carried most of the weight
I KNEW there was another, proper name for it (I used to be a big Tom Clancy fan), I just couldn’t recall what that was.
Wouldn’t the ice around where the sail punched through be broken up for quite a ways out?
To folks pointing out the logistical difficulties, that caused my initial doubt as well, but I figured they might have arranged to do a film shoot around a routine ice exercise or something.
I’m pretty surprised that they’d want a sub to break through the ice. Wouldn’t it potentially scratch the surface of the sail and ruin some of it’s (sonar) stealthiness? What’s the reason a sub would need to break through the ice that would make it worth the risk?
Not long; a few seconds. However, I don’t have direct experience with this: while I was on a deployment to the Arctic, my submarine had retractable bow planes, not fairwater planes.
We did dozens of surfacings through the ice, and always stationed a polar bear watch, consisting of a guy with dubious marksmanship qualifications and an M-16. :dubious: We were all pretty sure that if he did shoot at a polar bear, it would just piss the bear off. (Thankfully, we never saw a bear.)
You surface very slowly to avoid damage. It’s a constant upward pressure to break through.
Even after all those precautions, after our deployment, we needed major refit work. Our sail was pretty scratched up, and needed a lot of attention. More seriously, our sonar dome cover on the bow was damaged, which required a drydocking to replace.
As for the ice thickness, previous records are useless. The ice varies in thickness constantly as it builds up, moves, collides with another section and crumples upward or downward, etc.
You know the ice thickness by using under-ice sonar to determine where the ice starts, and you know the depth to the surface by the pressure of the water around you. Simple subtraction determines the depth of ice.
Oh, and it’s periscope. :rolleyes:
In my experience, not really, for a sub that surfaces level. However, submarines sometimes surface with an “up angle” to make it easier to use the forward access hatch instead of having to climb up and down the sail. See here.
