# Supersonic underwater projectiles? **URL:** \ **Category:** Factual Questions\ **Created:** [December 1, 2000, 10:20pm UTC](https://boards.straightdope.com/t/supersonic-underwater-projectiles/43646 "2000-12-01T22:20:36Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![black\_rabbit](https://avatars.discourse-cdn.com/v4/letter/b/f19dbf/32.png) [@black\_rabbit](https://boards.straightdope.com/u/black_rabbit)\ **Post date:** [December 1, 2000, 10:20pm UTC](https://boards.straightdope.com/t/supersonic-underwater-projectiles/43646/1 "2000-12-01T22:20:36Z")
[This NYT article](http://www.nytimes.com/2000/12/01/world/01RUSS.html), in a discussion of the 200mph Russian “Squall” torpedo, mentions in passing that American scientists have devloped supersonic underwater projectiles, but have so far been unable to adapt them for use as weapons. Just how the hell would one get something to move at supersonic speed through water? The same semivacuum bubble technology that Ivan uses on the Squall? ---
**Author:** ![djbdjb2](https://avatars.discourse-cdn.com/v4/letter/d/a88e57/32.png) [@djbdjb2](https://boards.straightdope.com/u/djbdjb2)\ **Post date:** [December 1, 2000, 10:31pm UTC](https://boards.straightdope.com/t/supersonic-underwater-projectiles/43646/2 "2000-12-01T22:31:57Z")
[http://www.newscientist.com/features/features\_224813.html](http://www.newscientist.com/features/features_224813.html) ---
**Author:** ![bibliophage](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bibliophage/32/7615_2.png) [@bibliophage](https://boards.straightdope.com/u/bibliophage)\ **Post date:** [December 1, 2000, 11:48pm UTC](https://boards.straightdope.com/t/supersonic-underwater-projectiles/43646/3 "2000-12-01T23:48:25Z")
See an earlier thread: [Mach 1 torpedos](http://boards.straightdope.com/sdmb/showthread.php?threadid=36195) ---
**Author:** ![Zenster](https://avatars.discourse-cdn.com/v4/letter/z/cdc98d/32.png) [@Zenster](https://boards.straightdope.com/u/Zenster)\ **Post date:** [December 2, 2000, 12:50am UTC](https://boards.straightdope.com/t/supersonic-underwater-projectiles/43646/4 "2000-12-02T00:50:26Z")
Any sonar operators out there to comment on what the ping from this devil would look like? Anyone hear of further research on acoustic/sonic torpedoes? Dolphins use acoustic packets to stun fish and the Navy was able to dent metal with sonic bursts back in the eighties, whatever happened to this technology? Imagine not having to reload or run out of ordnance. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [December 2, 2000, 1:19am UTC](https://boards.straightdope.com/t/supersonic-underwater-projectiles/43646/5 "2000-12-02T01:19:57Z")
> [@](#): > > Any sonar operators out there to comment on what the ping from this devil would look like? Probably something like _ **KABOOM!!!** _ . . . sub[/sub] Remember, it is supersonic, after all. ---
**Author:** ![Zenster](https://avatars.discourse-cdn.com/v4/letter/z/cdc98d/32.png) [@Zenster](https://boards.straightdope.com/u/Zenster)\ **Post date:** [December 2, 2000, 2:03am UTC](https://boards.straightdope.com/t/supersonic-underwater-projectiles/43646/6 "2000-12-02T02:03:03Z")
> [@](#): > > \*Originally posted by Chronos \* > \*\* > > > [@](#): > > > > Any sonar operators out there to comment on what the ping from this devil would look like? > > Probably something like > _ **KABOOM!!!** _ > . > . > . > sub[/sub] > > Remember, it is supersonic, after all. \*\* Yes, but sound travels faster in water, given that, unless the torpedo is also traveling faster than the speed of sound in water, there might be a chance for signal return. ---
**Author:** ![Arjuna34](https://avatars.discourse-cdn.com/v4/letter/a/eb8c5e/32.png) [@Arjuna34](https://boards.straightdope.com/u/Arjuna34)\ **Post date:** [December 2, 2000, 5:24am UTC](https://boards.straightdope.com/t/supersonic-underwater-projectiles/43646/7 "2000-12-02T05:24:32Z")
> [@](#): > > \*Originally posted by Zenster \* > \*\* > > > [@](#): > > > > \*Originally posted by Chronos \* > > \*\* > > > > > [@](#): > > > > > > Any sonar operators out there to comment on what the ping from this devil would look like? > > > > Probably something like > > _ **KABOOM!!!** _ > > . > > . > > . > > sub[/sub] > > > > Remember, it is supersonic, after all. \*\* > > Yes, but sound travels faster in water, given that, unless the torpedo is also traveling faster than the speed of sound in water, there might be a chance for signal return. \*\* That’s the whole point, though- the torpedo IS traveling faster than the speed of sound in water. Arjuna34 ---
**Author:** ![LIONsob](https://avatars.discourse-cdn.com/v4/letter/l/76d3ee/32.png) [@LIONsob](https://boards.straightdope.com/u/LIONsob)\ **Post date:** [December 2, 2000, 5:40am UTC](https://boards.straightdope.com/t/supersonic-underwater-projectiles/43646/8 "2000-12-02T05:40:48Z")
It seems to me that if you were directly in the torpedos path you would not hear it till impact, if you were not in its path it would be loud as hell. Kind of like a high velocity rifle shot. Peace LIONsob ---
**Author:** ![PerfectDark](https://avatars.discourse-cdn.com/v4/letter/p/ebca7d/32.png) [@PerfectDark](https://boards.straightdope.com/u/PerfectDark)\ **Post date:** [December 2, 2000, 6:22am UTC](https://boards.straightdope.com/t/supersonic-underwater-projectiles/43646/9 "2000-12-02T06:22:10Z")
What would the shockwave of a supersonic projectile in water be like? Would it be much the same as in air? ---
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [December 2, 2000, 11:11am UTC](https://boards.straightdope.com/t/supersonic-underwater-projectiles/43646/10 "2000-12-02T11:11:09Z")
if you are near the target, it migh look like it is moving in reverse ---
**Author:** ![Zenster](https://avatars.discourse-cdn.com/v4/letter/z/cdc98d/32.png) [@Zenster](https://boards.straightdope.com/u/Zenster)\ **Post date:** [December 2, 2000, 11:25am UTC](https://boards.straightdope.com/t/supersonic-underwater-projectiles/43646/11 "2000-12-02T11:25:05Z")
Anyway, I knew that a trans-sonic underwater projectile might outpace sonar. I’m just curious as to whether there is anything short of subsurface laser range finding (lidar) that will detect these little buggers. No one’s answered my inquiry about acoustic packeted “sonic torpedoes” yet, so there! Nyyeahhhh!