Moving the dive planes and Mk 48 Swimout?

[WargamerScott]

Two questions:

Why did they move the dive planes from the sail to the bow on the 688(i)? I remember reading how the original sail-mounted dive planes on the LA-class subs was such a big improvement. What changed?

Second: If I remember correctly, the old, but great, RSR game from Microprose had Mk 48 Swim-Out torps. I guess the swim-out idea never worked in reality? Or is it still under development?

[Mocbo]

Is rumour that the seawolf uses this Torps.
660mm tubes for 533mm adcaps are a very mysterios.

It is possible that the swimout program was canceled due the End of the Cold war.

Greetings

Moc

[TLAM Strike]

They moved the diving planes to the hull beacuse it made it easyer to surface through the ice and its quieter (I think).

The swimout fish caused lots of wear on the torpedo tubes so they went back to normal launching IIRC.

[LuftWolf]

http://www.military.com/Resources/EQ...21&cat=v&lev=2

In addition to having twice the number of torpedo tubes (eight) the tubes are also of a larger design which allows the current Mk 48 ADCAP torpedo to "swimout" under its own power rather than launched with a blast of high pressure air. This allows the Seawolf to have a much lower launch "signature" than earlier boats.

[SeaQueen]

Originally Posted by WargamerScott

Two questions:

Why did they move the dive planes from the sail to the bow on the 688(i)? I remember reading how the original sail-mounted dive planes on the LA-class subs was such a big improvement. What changed?

Handling the submarine became slightly harder on account of the dive planes being mounted further from the center of mass, but I think they gained the ability to retract the forward dive planes and surface through ice without damaging them.

Second: If I remember correctly, the old, but great, RSR game from Microprose had Mk 48 Swim-Out torps. I guess the swim-out idea never worked in reality? Or is it still under development?

That was my first submarine simulation. According to my boss, at the time, it was actually more sophisticated than any submarine combat model that existed in the Pentagon, believe it or not.

They call the HP air torpedo tubes "impulse" launched torpedoes and the others swimouts. I don't know if they got it to work or not on the Seawolf class.

[WargamerScott]

First, thanks to everyone who replied...it was very informative (and shows me how out-of-date I am since the end of the Cold War ).

Originally Posted by SeaQueen

That was my first submarine simulation. According to my boss, at the time, it was actually more sophisticated than any submarine combat model that existed in the Pentagon, believe it or not.

I completely believe it. IIRC, Microprose's stealth simulator (which was very good if a bit buggy) supposedly raised a few eyebrows in the Air Force when they saw how realistic the sim was vis-a-vis the then still classified F-117 program.

Microprose was a class act, no doubt about it. They really knew their stuff.

[Kapitan]

diving planes to the front because they have more control there than on the sail, also its quieter but does come at a price you loose some sensativity in the soar due to water flow over the planes.

the 688 was hard to surface through ice because of the planes and they were also prone to being damaged while coming alongside (look on bills site the picture), what could happen is come along side and the plane would hit the side of the ship either bending or breaking it.

also the dive planes on the sail over hand the side of the sub so thats how the above happens.

during high speed you can retract bow planes you cant retract sail planes so if the helmsman stuffs up and pushes the wheel forward you go down cant happen if bow planes are retracted

thats why russian high speed submarines put them on the bow and not the sail

[SeaQueen]

Originally Posted by WargamerScott

I completely believe it. IIRC, Microprose's stealth simulator (which was very good if a bit buggy) supposedly raised a few eyebrows in the Air Force when they saw how realistic the sim was vis-a-vis the then still classified F-117 program.

Microprose was a class act, no doubt about it. They really knew their stuff.

The thing I thought was interesting, though, was that they really didn't make "realistic" flight sims like we think of them today. It really shows how primative computers were then.

[Kazuaki Shimazaki II]

Originally Posted by Kapitain

diving planes to the front because they have more control there than on the sail, also its quieter but does come at a price you loose some sensativity in the soar due to water flow over the planes.

Can't you get that sensitivity back (at the price of degraded maneuverability, naturally; but you aren't gonna maneuver hard and try to listen at the same time) by sticking those planes in at low speed? If so, it sounds like there is almost no disadvantage at all.

[Sub Sailor]

The main consideration for the move was the vibration cause unwanted noise. And it is cheaper because you don't have to rotate the planes to vertical to go through the ice.
Actaully contol was very good with sail planes, the location was right and at high speeds you locked them and used only the stern palnes because of the area of the sail planes. Sail planes really provided dive and lift.

Ron Banks MMCM(SS), USN(Ret)

[SeaQueen]

Originally Posted by Sub Sailor

The main consideration for the move was the vibration cause unwanted noise. And it is cheaper because you don't have to rotate the planes to vertical to go through the ice.
Actaully contol was very good with sail planes, the location was right and at high speeds you locked them and used only the stern palnes because of the area of the sail planes. Sail planes really provided dive and lift.

Ron Banks MMCM(SS), USN(Ret)

I was under the impression that the sail and bow planes in the early los angeles boats were not sufficiently strengthened to go through the ice at all. Is this incorrect?

[XabbaRus]

I think so.

The swim out capability was cancelled not cos it didn't work but a they had problems with toxic fumes being left in the tube even after it was drained or something like that.

AFAIK the planes on the 688 were moved to the hull as the sail planes weren't strong enough. Also the sail was toughened up so I don't know if 688/688 VLS can go through the ice.

[Deathblow]

I've seen pictures where a 688 with sai planes verticle had broken through the ice, but I think that the depth of ice that could be penetrated was boosted when the bow planes were moved to the hull and not the sail iirc.

interesting article about icebreaking.
http://www.chinfo.navy.mil/navpalib/...he_arctic.html

The advantages of sail planes is that you can link the two planes with a crossing bar through the sail, making its mechanical operation simple and more fail proof. Other advantage is that its further from the spherical sonar so flow noise from the planes intereferes less with sonar performance. Disadvantes is that the sail placement is further back from the bow so has to be larger to afford the same "lift" ability as planes further toward the bow.... and the fact that ice breaking is more limited.

Supposedly the SW uses a new "Air turbine" system to eject torps instead of the "Air piston" that 688 used, because its supposedly quieter.

I've read that the Virginia subs may use a elastomeric system to make the subs lauchers simple, independent of compressed air, and less maintenace requirements.

http://www.chinfo.navy.mil/navpalib/...er_balloon.htm

and if fully electric subs become a reality maybe even a fully electric launcher

http://www.onr.navy.mil/about/confer...eml_system.pdf