All posts by Capt Ray Wellborn

Captain Ray Wellborn, USN (retired) served over 13 years of his 30-year Navy career in submarines. He has a BSEE degree from the US Naval Academy, and a MSEE degree from the Naval Postgraduate School. He also has an MA from the Naval War College. He had two major commands at sea and one ashore: USS MOUNT BAKER (AE 34), USS DETROIT (AOE 4), and the Naval Electronics Systems Engineering Center, Charleston. He was Program Manager for Tactical Towed Array Sonar Systems, and Program Director for Surface Ship and Helicopter ASW Systems for the Naval Sea Command in Washington, DC. After retirement in 1989, he was the Director of Programs, ARGOTEC, Inc.: and, oversaw the manufacture of advanced R&D models for large underwater acoustic projectors. From 1992 to 1996, he was a Senior Lecturer in the Marine Engineering Department of Texas A&M, Galveston. Since 1996, he has been an independent consultant for International Maritime Affairs.

A View From The Booth: Getting A Rivalry Defined By Commonality

I think a lot of our blog visitors would be interested in the article below written by Bob Socci.

A half minute earlier, Army head coach Rich Ellerson took the one timeout he’d left his team for the waning seconds of the 113th football encounter of West Point Cadets and Navy Midshipmen.

If only to delay the inevitable.  And for half of the 69,607 at Philadelphia’s Lincoln Financial Field, prolong the misery.  During the stoppage, the stadium’s massive video boards featured a close-up of the Commander-In-Chief’s Trophy, which for the 16th straight year would belong to someone else.

When the break ended, Navy quarterback Keenan Reynolds, who was about to be named most valuable player, took the game’s penultimate snap.  There was need for merely one more kneel-down to seal the Mids’ 11th consecutive win in the series.

In that moment, as the final seconds elapsed, Ellerson’s counterpart, Ken Niumatalolo, was compelled to do two things.  The first involved one of his veteran leaders.  The second, one of Army’s.

As a sophomore, John Howell caught the longest pass in Army-Navy history, running the last of his 77 yards toward the same south end of The Linc where the Mids now aligned in victory formation.  Howell had shredded the ligaments stabilizing his right knee in late September, suffering an injury sure to be career-ending.  For weeks, he rehabbed from surgery mindful of a single goal: to recover enough to run out of the locker room with his Academy brothers one last time, in time for Army-Navy.

Howell made it.  He was at the head of the line forming in the stadium tunnel, carrying a Marine Corps flag.  Emerging into the open air of South Philly, Howell jogged — as his teammates charged — along the Mids’ sideline.

That remained his vantage point for the football theatre ongoing into early evening.  Howell had watched Navy rally for a late 17-13 lead, before seeing Army threaten to eclipse that advantage.

But 14 yards from possibly stopping their skid against the Mids and recapturing the CIC title for the first time since 1996, the Black Knights fumbled their chance away.  In the sudden change of circumstances, Niumatalolo saw an opportunity to give Howell more than he could ever wish for.

Reynolds knelt twice, before and after Ellerson’s last timeout.  Then, for the final act of Army-Navy: Episode 113, Niumatalolo sent Howell onto center stage to stand over Reynolds’ right shoulder.

In the third line of fine print in the game summary, as part of the Mids’ participation report, “33-Howell, John” will always mark the time Niumatalolo helped a senior re-define the end of his playing career.

To the surprise of no one who knows him, it was a classy gesture by Niumatalolo.  So was his next.  Once Reynolds’ knee dropped to the ground, Niumatalolo sought out Ellerson and went searching for Trent Steelman.

Steelman was Army’s four-year quarterback and career touchdown leader.  And in the eyes of the rival coach, an all-time competitor.  When Niumatalolo finally got to Steelman, he said as much.

“To be honest, I don’t really remember much, I was pretty torn up,” an understandably emotional Steelman told reporters.  “I think he said that I was one of the toughest players he’s ever seen and just a great player, and I respect him for that.  He’s a great coach.”

“We should all be proud as Americans that that guy is going to go protect our country,” Niumatalolo explained in his own press conference.  “They don’t get any tougher than Trent Steelman.  Four years starting at West Point, a military service academy.  I know everyone in our locker room has nothing but respect for that young man.”

This was Niumatalolo’s 15th Army-Navy game.  His first two ended as Steelman’s last two, in absolute anguish over an excruciatingly close outcome.

In 1995, he was an assistant to Charlie Weatherbie, who eschewed a late chip-shot field-goal try that could have separated the rivals by two scores.  The Black Knights mounted a goal-line stand and marched 99 yards to a 14-13 triumph.

The following season, again with Niumatalolo assisting Weatherbie, the Mids relinquished an 18-point lead and failed to score on two late, deep drives.  They fell by a 28-24 final.

Fifteen years later, Niumatalolo’s fourth Army-Navy experience as head coach ended with a six-point victory, thanks to a pair of fourth-quarter field goals in Landover.  After his fifth, last Saturday, he expressed the kind of bittersweet emotions evoked only when Cadets compete with Midshipmen.

Brother of an Army colonel, Niumatalolo understands that while other rivalries are fueled by differences, this one is defined by commonality.  He preaches humility and respect, for the competition and the game itself.  As do his players.

“It’s amazing because we have the utmost respect for those guys,” senior linebacker Keegan Wetzel said, as a member of the eighth straight class of Mids to record a career sweep of their mirror images.  “I tell them when I pick them up, ‘I love you brother,’ and I don’t even know them.

“You can see it in their eyes that they go through the same things that we do.  They are from the same backgrounds, the same families and they fight and claw the same way that we do.  To beat those guys is a privilege and an honor.  Nobody out there is going to give anybody an inch.”

Per usual, Wetzel, an Academic All-American, is correct.  Army earned every one of the more than 14,400 inches amounting to its 400-plus yards of total offense, including 203 more rushing yards than Navy.  And the Mids earned what they got against a high-pressure defense, despite being frustrating into six punts and a fumble that led to the Black Knights’ lone lead.

Navy also earned the win.  It made more plays and fewer mistakes.  In the end, performance equaled precedent.

The precocious Reynolds rallied his offense, exactly as he’d done at Air Force in early October.  He prolonged the go-ahead drive with a throw to Geoffrey Whiteside — freshman to sophomore — converting a 3rd-and-8.  Two plays later, he deked a pair of pass-rushers to escape up the right sideline for 11 yards.  He then dropped a perfect pass onto the sure hands ofBrandon Turner.

The 49-yard strike set up one more Reynolds run, from eight yards out, with 4:41 to go.  He slipped a hit and beat an Army cornerback to the pylon, angling right toward the Brigade of Midshipmen in the stadium’s northeast corner.

On the ensuing drive, the Mids lived up to their defensive credo, to make `em snap it again.  Freshman cornerback Kwazel Bertrand made the first of two touchdown saving tackles.  SeniorTra’ves Bush delivered the other.

Bertrand slipped in pass coverage, yet lunged from all fours to trip receiver Chevaughn Lawrence at the Navy 40.  Further downfield, at the Mids` 19-yard line, Bush reached out for a one-handed takedown of Raymond Maples.  For the umpteenth time in his Navy career, he was the right man in the right spot.

After Bush’s stop, the Black Knights had to snap it again, and again.  The gritty Steelman picked up a first down at the 14-yard line.  But on the next play, the 11th of the series and Army’s 72nd of the contest, the Cadets dropped the ball.

Steelman and fullback Larry Dixon mishandled the mesh.  The football squirted loose.  And Barry Dabney, in his only rep of the day, got his hands around it, to help the Mids hold on.  Army was undone again by a fumble.

It was the Black Knights’ fifth of the game and third recovered by Navy.  It was their eighth lost this season inside the opposition’s 20-yard line.

Not long after, with little time to stop the tears that flowed from such a heart-wrenching end to his career, Steelman asked the press to pin the turnover on him.  Dixon did the same.  Filling the unenviable duty of answering for the indescribable, each `manned up’ to spare the other of fault.

Then, you expect nothing less of a Cadet or Midshipman.

And what of Ellerson?  In his post-game presser, he was succinct.

“It was a mesh fumble,” he said.  “It was a quarterback-fullback mesh; it’s fundamental.”

To a subsequent query about the Reynolds throw and Turner catch, Ellerson replied with his unhappy recap of what, in his view, decided the outcome.

“That wasn’t the difference,” Ellerson asserted. “The difference is the kicking game and turnovers.  Those are the things that correlate with success; those are the things that are fundamental to the game.  The scoreboard will reflect those things.  It will reflect the kicking game; it’ll reflect turnovers.”

And it will reflect the fact that Navy ensured itself at least eight wins for the ninth time in 10 years and claimed its eighth CIC title in that same span.  Already, the Mids had earned a ninth bowl bid in those 10 seasons.

It will also reflect a 2-10 finish to the Cadets’ 12th season of four or fewer victories in the last 15 years.  They are now 17-32 overall under Ellerson; 5-19 since posting their only winning record of the past 16 seasons (7-6 in 2010).

Yet in the weeks before, and minutes after the scoreboard went final, there was scant acknowledgement by Ellerson of what Navy’s accomplished, remarkably, for so long.  Already, as evidenced by pre-game comments Niumatalolo made to a radio audience, the Mids sensed a disrespect uncharacteristic of Army-Navy.

Shortly after Ellerson returned to his locker-room office, he gave them their first bulletin board pin-up for 2013.  Speaking to reporter Sal Interdonato of the Middletown, N.Y. Times-Herald Record, here is some of what Ellerson had to say:

  • “Give (Reynolds) some credit. He made some good plays and he’s hard to tackle.  But, he’s not that hard to tackle…We were there.  We have people in position to make plays in that game.  If we do those things that are fundamental, we beat them by three touchdowns.  We’re better than that bunch. We lose the turnover by two.
  • “We are playing a good football team.  We have them right by the throat.  We could have put them away in the first half.  We didn’t have to wait until the end…They are better than Air Force, but they are a touchdown better than Air Force.  We are better than they are.  It’s (expletive).  It’s (expletive).”

You can be the judge of whether Ellerson’s implications are an indictment of others, but not himself.  On CBS, analyst Gary Danielson found Army’s play-calling “questionable” on two crucial drives, when it appeared Ellerson was willing to put the onus solely on a placekicker in only his second start.

Ellerson’s been steeped in Army-Navy his whole life.  His father and two older brothers were West Point grads; one of them the captain of the ’62 Cadets.  He’s also experienced it from the other side, as a Naval Academy plebe.

He’s obviously a bright coach, good enough to go 56-34 in his prior stint at Cal Poly and smart enough to understand the fallacy inherent when comparing results.  He should also beware of the hypocrisy of such analysis.

The Mids who faced Air Force on the road were 1-3, had yet to launch the Reynolds era and had to defend 200-yard-a-game Cody Getz on two healthy ankles.  As for Army’s win over the Falcons, the Black Knights have every right to relish every bit of their 20-point triumph — even if, to borrow an Ellerson phrase — Air Force lost the turnover by five.

Thirty years ago, Ellerson was an assistant coach at his alma mater, the University of Hawaii, when he helped recruit a quarterback by the name of Ken Niumatalolo from Honolulu’s Radford High.  Ellerson had wound up playing for the Warriors, after transferring from the Academy.

Asked why he left Annapolis by New York Times writer Joe Drape for his book, Citizen Soldiers, Ellerson replied: “I was nineteen — I had no excuse, sir.”

Assuming he returns for the 114th Army-Navy game, Ellerson will do well to remember that phrase.  He’d do better to emulate the kid he once coached, and the young men he now coaches.

One points to himself in defeat, while thinking first of the players in victory.  The others, as one of their own might say, fight and claw, never giving an inch.

And should they come up short, offer no excuse, sir.

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Do you want to win a trip to space? Here is your chance.

To celebrate the 50th anniversary of Seatle’s  Space Needle, it was announced that the formal contest will be held with the final winner going up to suborbit, with about 6 minutes of zero gravity.  This is once in a lifetime opportunity to see the Earth from space.  Many astronauts call this a truly life changing experience.

Since the final landing of the space shuttle the field of human space travel has been turned over to the private companies, one of which, Space Adventures, will be responsible for designing a vehicle to take the winner of the Space Needle contest into space.  The estimated price of the grand prize is $110,000.

What do you need to do to enter?

  1. Sign up to enter at the Space Needle’s website
  2. Be lucky to be the randomly selected 1,000 finalists
  3. Create a 1 minute video that shows why you are the best candidate
  4. Be the lucky one chosen by the public
  5. Pass the fitness aptitude test
  6. Go up in space

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The decibel, abbreviated dB, is used to denote a ratio that is ten times, or “deci” times, a unit the “Bel,” as so named by its celebrated devisor whose name it bears, Alexander Graham Bell, the inventor of the telephone. The decibel, dB, thus became the commonly used unit of measure for expressing a change in power from an original setting to that being measured, that is to say, a dB is a relative power measurement.
Since dB expresses a dimension-less ratio between two power-levels, the caveat for the measurement is that it must be taken at the same point as the reference so as to have the same “acoustical impedance.” Whereas, acoustical impedance, symbolized ρ•c, is the product of the density, ρ, of the medium of propagation, and the speed, c, of sound in it.
The dB is therefore used to express a relative increase or decrease in acoustic power or pressure, and their corresponding electric power-levels, as a ratio with either a previous level or a specified standard, or a reference. Such reference typically is in the style of a minimum discernible signal, a MDS, at a sound receptor such as the human ear, whose minimum audible field, the MAF, for the human ear is referenced as 0 dB.
This MAF for the human ear has been measured by experimentation to be at an Intensity, I, of 1.0 x10-16 W/m2 expressed as a Power per unit Area, This equates to a minute pressure, p, of 2.0 x 10-4 dyn/cm2, which most often is expressed as ref 20μPa, whereas 20 micro-Pascals is a pressure in MKS units.
The smallest change in sound-power level, ΔP, the normal human ear can detect, or “sense,” is about 1 dB ref Po. More than likely, such hearing sensitivity was considered by Alexander Graham Bell as the minimum change to which all other sound should be referenced.
Thus, by definition, a decibel, 1 dB ref Po, is ten times the base-ten logarithm of a power ratio equal to the one-tenth root of ten. For instance, the power per unit area, the “Sound Intensity Level,” SIL, of a quiet whisper is measured to be 18 dB, that is, its “volume” was 18 dB above the MAF. If that particular volume-setting is increased in intensity by 25.9%, then by this convention it is said to be “up” 1 dB ref Po, where ref Po denotes the original setting 18 dB.
This widely acknowledged convention is shown below in notational form:
(The number of) dB ref Po = 19 dB – 18 dB = 1 dB ref Po; and,
converting 1 dB by dividing by 10 yields the exponent of ten as 100.1,
which equals 1.259 and denotes a 25.9% increase above the original.
Further, to be precise, +3dB ref Po by logarithmic calculation is the result of a doubling of its original power level, such that:
10log10 [(2.0 ∙ Po) ÷ (Po)] = 10log10 [(100.30103)]; and,
rounding the exponent to 0.3 the calculation approximates
10log10 [(100.1)3] = 3 dB ref Po, which is a cube of its base value.
Moreover, a +10 dB gain in power level implies a 10-fold increase over the original level, 10 :: 1, whereas a -20 dB loss implies a 100-fold decrease, 1/100 :: 1, such that:
10log10 [101 ÷ 100] = 10 x (+1 – 0) = +10 dB ref Po; and,
10log10 [10-2 ÷ 100] = 10 x (-2 – 0) = -20 dB ref Po.
The decibel is also used to express either voltage or current ratios, as either an electro-motive force, E, in units of volts, V, or a magneto-motive force, I, in units of amperes, A. Notably, these electrical forces are squared terms in their respective power-expressions, acting as if their motive force was an “electrical-pressure,” where P = E2/R = I2R; and,
P2, in dB ref P1, = 10log10 [(V2 /V1)2], and 10log10 [(A2 /A1)2]; or,
= 20log10 [(V2 /V1)], and 20log10 [(A2 /A1)], whereas R1 = R2.
Strictly though, when the decibel is used to express voltage or current ratios in lieu of power ratios, then the voltages or currents in the expression must be measured at places having identical electrical impedances, that is, R1 ≡ R2.
Further, by extension, the relation between the number of decibels and the corresponding ratios of voltages and currents are sometimes applied where the values in the ratios are not the square roots of the corresponding electrical power ratios, that is, not from the initial E22/R2 and E12/R1 expressions. To preclude confusion, a specific statement of the particular application should accompany such usage. Preferably, such extensions of terms should be avoided.
Intensity, I, is defined in units of power, P, applied over an area, A, which is in units of square-length unit, such as m2. Whereas, P is work per increment of time, t, in units of seconds, s, and work is a force, F, applied in a given distance, or length, l, then P is in units for force-length per time, F∙l/t, such as, ft•lbf/s, dyn•cm/s, or N•m/s.
As defined in Newton’s Laws, F is the instantaneous rate of change of momentum with respect to time; whereas, momentum is the inertia of a body-mass, m, moving with some velocity, v, and defined in units of mass-length per increment of time, t.
By calculus, the time-derivative of this defining product for momentum, as it undergoes an instantaneous rate of change with respect to an infinitesimal increment of time, dt, yields an expression that defines force, F, with two additive terms. The first term is the multiplication of the mass, m, by the time-derivative of the velocity, v, which yields, m∙ (dv/dt). The second additive term is the multiplication of the velocity, v, by the time-derivative of the mass, m, which yields, v∙ (dm/dt).
Notably, for momentum, if only the velocity term is undergoing an instantaneous rate of change with respect to time, but not its mass, then dm/dt = 0, and thus the additive term of v∙(dm/dt) = 0. Therefore, classically, F = m∙a, where dv/dt = a, which is acceleration in units of length per square-time, ft/s2, cm/s2, or m/s2, where m is the symbol for mass in units of lbf/ft/s2, g or kg, whereas Force, F, is expressed in units of lbf, dyn, or N—a la, a Newton of force.

Definition. Sound is a distinguishing physical wave, a sound-wave, per se. Lord Raleigh in his work, “Theory of Sound,” volumes 1 and 2, Dover Publications, New York, 1945, defined a sound-wave as an alteration in pressure, stress, particle displacement, or particle velocity that is propagated in an elastic material, or the superposition of such propagated alterations in that medium. Further, a sound-sensation is produced through the ear by the above alterations.
Van Nostrand’s Scientific Encyclopedia defines sound somewhat more physically as a longitudinal elastic wave-motion propagated by alternate compressions and rarefactions of the medium. The analogy stated therein is that sound is like the propagation of a “bump,” or a “jerk,” from a freight-train’s engine to its caboose.
Thus, a sound-wave of acoustical energy only can propagate in a medium, being it a gas, a liquid, or a solid; and, it is either deflected or refracted, or both, at the laminar boundary between media of differing densities. In the denser media, or in a heated gas, the molecules orbit in closer proximity to one another such that the “bumps” propagate faster. Distinctly, the closer the orbiting molecules are to one another then the better the propagation of the sound– that is, the sound is demonstrably “louder.” Conversely, void of any molecules to “bump,” such as in a vacuum, sound cannot propagate; in other words, you cannot hear yourself scream in space.
Sound-intensity is defined as Power per unit area, which is the average rate (time) of sound-energy transmitted in a specified direction as it impinged on an area normal to this direction of propagation. In notational form, sound-intensity, I, of a spherical-wave, or even a plane-wave, in the direction of propagation can be expressed as being directly proportional to the square of its impinging pressure and indirectly proportional to the acoustic impedance in which it is propagating, that is:
I = [(pressure) 2 ÷ (medium-density) ∙ (sound-speed)].
I is expressed in terms of the square of the impinging sound-pressure, p, with respect to the acoustical impedance of the medium, ρ∙c. Accordingly, the resultant-product of the density of the medium, ρ, multiplied by the speed of sound, c, in that medium, is (kg/m3) ∙ (m/s) in MKS-units, which further reduces to Newton-seconds per cubic-meter, N∙s/m3. The square of p is in (N/m2)2. And, to be a comparable sound-intensity level, the sensed I must be in a ratio with a previously sensed level, or a reference-level, I ref, where both are in units of power per an area common to both, P/Ao, a la, the sensing area of the ear, or the sensing area of an underwater transducer.
In either case, Ao is a unit-area equal to 1, since A1 ≡ A2, such that A1 / A2 = 1. Therefore, sound-intensity, I, in SI-units, is Watts per unit-square-meter, W/mo2, that is:
F, in N, = kg∙m/s2; when v∙ (dm/dt) = 0; whereas,
P, in W, = [(kg∙m/s2) •m/s] = N•m/s; whereas,
I, inW/m2 = [(N•m/s)/m2]; factored with (N/m2) ∙ (m2/N) • (s/s) = 1.0, yields,
I, inW/m2 = [(N•m/s)/m2]•[(N/m2)∙(m2/N)•(s/s) = [(N/m2)2] ÷ [N∙s/m3]; which is I, inW/m2 = [(N/m2)2]•[(kg•m/s2)•s/m3)] = [(N/m2)2] ÷ [(kg/m3)•(m/s) = p2/ρc.
Particularly, the squared sound-pressure, p2, is expressed in units of (N/m2)2, and the acoustic impedance, ρ∙c, is expressed in units of N∙s/m3. Thus, I reduces to (N•m/s)/m2, which relates to power per unit-area, P/Ao, which in W/m2 can be converted to CGS-units by multiplying by W/m2 by a conversion factor of 107, and conversely by 10-7.
Discernibly though, when sound-intensity, I, as P/Ao, is expressed in dBref, then it is known as a Sound-Intensity Level, SIL; and, by decibel-definition is expressed as a power ratio for a common area, a la, a unit-area, in that, SILdB = 10log10 [P1 :: Po], where Po is some Pref MDS.
Typically, the measure of SILdB in any medium is referenced, that is, “zeroed,” to some set standard, which is not necessarily the MDS that the acoustical receptor can detect, a la, “sense,” in that medium. For veritable comparison of differing sound-intensity levels given in decibels, dB, it is imperative that this reference-level be noted.
Simply though, the ratio of I2 / I1 reduces to p22 / p12, where ρ∙c / ρ∙c = 1. Thus, for a Sound-Pressure Level, SPLdB, in air, the reference, pref air, is the Minimum-Audible-Field, the MAF, for the human ear in air, which is:
pref MAF = 2.0 x 10-4 dyn/cm2 = 2.0 x 10-5 N/m2 = 20 x 10-6 Pa
= 20 μPa, where N/m2 is defined in MKS units as a Pascal, Pa.
Remarkably though, for sensing acoustical sound-pressure levels in water, modern-day electrostriction-ceramic transducers, coupled with advanced digital, number-crunching, acoustic signal processors, are “zeroed” to 1 μPa, which is 20 times more sensitive as a reference than the MAFair; whereas,
20log10 [(1/20) μPa] = -26 dB ref 20 μPa “down” from that for 20 μPa.
The characteristic acoustical impedances for differing media are experimentally determined, and the measurement of each is certified as a physical constant for universal reference. As such, the gaseous density of air and the speed of sound in it are delineated below– as measured in the sonic frequency range at 0 degrees Celsius, C, and 760 millimeters of mercury, mmHg, with 0.03-mole-percent content of CO2. Furthermore, from 0o C to about +20o C, the speed of sound in air, cair, demonstrably varies by a factor of [60.7 x Tdegrees C]. For reference some comparable values are shown below:
Density of medium: ρo air = 1.2931 x 10-3 g/cm3 at 760 mmHg; and,
ρ1 air 200 C = 1.2078 x 10-3 g/cm3 at 760 mmHg.
Speed of Sound: co air = 3.3145 x 104 cm/sec at 0oC; and,
c1 air 20oC = 3.4359 x 104 cm/sec at 20oC; such that,
Acoustic Impedance: ρo∙c air = 4.2860 x 101 dyn∙s/cm3, and,
ρ1∙c air 20oC = 4.1499 x 101 dyn∙s/cm3.

Moreover, SIL ref air is derived from the p ref MAF, which is 2.0 x 10-4 dyn/cm2, thus:
I air, in W/cm2 = (2.0 x10-4)2 ÷ (4.2860 xl01) = 9.3327 x10-10; convert with x10-7,
Io air, in W/m2 = (9.3327 xl0-10 x10-7) = 9.3327 x10-17; then, in dB,
SIL ref W/m2 = 10log10 [(9.3327 x l0-17) = [9.7 dB -170 dB]
≈ -160 dB ref, the reference; whereas, the inverse-log yields,
Io air, in W/m2 = 10-16 W/m2, which is the reference, Io air; therefore,
SIL dB = 10log10 [I] -10log10 [Io air]; whereas, for Sound Pressure Level,
SPL dB = 20log10 [p] -20log10 [po air]; whereas, a SIL of -160 dB equates to
SIL dB = 0 dB as referenced to 10-16 W/m2; and,
1 dBref 10-16W/m2= -159.3 dB – (-160.3 dB] = 10log10 [10-15.93] -10log10 [10-16.03];
10-15.93 x107 = (p)2 ÷ 4.286 x101; then, solving for p yields,
p = 2.244 xl0-4 dyn/cm2 = 2.244 x10-5 N/m2 = 2.244 x10-5 Pa; where,
(2.244×10-5 Pa) ÷ (6.8945 xl03 Pa/lbf/in2) = 3.255 x l0-9 lbf/in2.
This is the math that proves that our binaural hearing system can detect very minute changes in sound-pressure levels, within our audible frequency-range. By convention, that audible frequency-range is known as the [our] sonic band. Its range is from 16 Hz to 16 kHz, with a maximum sensitivity at about 2 kHz, from which our 2,000 Hz conversational band extends to about 4 kHz . Also, by convention, frequencies below 16 Hz are sub-sonic, whereas those above 16 kHz are ultra-sonic, and thereby denote sound-frequencies that are inaudible—for us. Notably, super-sonic is a speed greater than the speed of sound, c, in reference to the medium of propagation.
Sound percussions, “beats and bumps,” vary in intensity. As an example, consider an explosion of 50 pounds of TNT, which results in a change of SPL equal to one atmosphere, Δ14.6972 lbf/in2. The SPLdB for this near-instantaneous change of pressure– measured 10 feet from the source, reference 0.0002 dyn/cm2, or 20 μPa, is as follows:
SPL ref 20 μPa = 20log10 [(14.6972 lbf/in2)∙(6.8945 x103 Pa/lbf/in2)] -201og10 [20 x10-6Pa]
≈ [40 +60 dB] – [26 -120 dB] = 194 dB ref 20 μPa; whereas,
1.000 atm = (14.6972)∙(6.8945 x103 Pa)∙(9.869 x10-6 atm/Pa)
= 1.0 xl06 μbars = l.0 xl06 dyn/cm2 = 1.0 xl05 Pa.
Some examples of sound-intensity in air, referenced to 10-16 W/m2, are:
(1) The threshold of painful sound is 130 dB, or about 0.009 lbf/in2.
(2) The subway-express passing the station emits 102 dB, or about 0.0004 lbf/in2.
(3) Normal conversational speech at one meter is 70 dB, or about 0.000009 lbf/in2.
(4) A quiet whisper heard at five feet is 18 dB, or about 0.00000002 lbf/in2.
Notably, it is painful to feel (sense) a change in pressure on your ear drum of 9/1000th of pound per square inch.
For a denser media, no pun intended, consider seawater at 15 degrees Centigrade, and a salinity of 36 ppt, parts per thousand, which equates to a Specific Gravity, also a unit-less ratio, of 1.025; such that,
Density, ρo seawater = 1.025 g/cm3; and,
Speed of Sound, c seawater = 1.505 x l05 cm/s; such that,
Acoustical Impedance, ρo∙c seawater = 1.5426 x 105 dyn∙s/cm3, at 15oC, and so = 36 ppt.

 Discernibly, the acoustical impedance of seawater, ρo∙cseawater, is about 3600 times greater than ρo∙cair; in that, (1.5426x l05) ÷ (4.2860 x 101) ≈ 3600:
10log10 [3600] = 35.5630 ≈ +36 dB ref ρ∙c air “up” from air.

In that the speed of sound, c, varies directly with the density of the medium, the acoustical impedance varies accordingly. Notably, if the same sound-pressure, p air, is applied in seawater as intensely as it was in air, then the corresponding SIL seawater will be more due to the greater acoustical impedance in the denser medium.
Notably, the sound in seawater will be +36 dBref ρ0∙c air “louder” than it was in air. Thus, sound-intensities in different media vary directly with the characteristic acoustical impedance of the propagating medium, ρc ref medium. And, for example, the SPL air of normal conversational speech heard at 4 feet, or about 120 cm, is 0.645 dyn/cm2, therefore:
SIL air = 10log10 [((0.645 dyn/cm2)2 ÷ (42.86 dyn∙s/cm3)) x10-7)] -10log10 [10-16 W/m2]
≈ [(-4 dB) –(16 dB) –70 dB] -[-160 dB] = 70 dB ref 10-16 W/m2.
If that same sound-pressure of 0.645 dyn/cm2 in air is applied in seawater, then for a SIL seawater, a SIL ref for that denser medium must be referenced to the MAF in air, such that:
IMAF seawater = ((0.0002dyn/cm2)2 ÷ (ρo∙cseawater)) x10-7)
= ((4.0×10-8) ÷ (1.5426xl05)) x10-7)
= 2.5930 x10-20 ≈ 2.6 x10-20 W/m2; and,
SILseawater = 10log10 [((0.645)2 ÷ (ρo∙cair)) x10-7] – 10log10 [2.6 x10-20 W/m2]
= 10log10[((4.160 x10-1) ÷ (1.5426xl05)) x10-7mo)] – 10log10 [2.6 x10-20 W/m2]
≈ [(-4 dB) –(2 +50 dB) +(-70 dB)] – [4 -200 dB] = 70 dB ref 2.6 x 10-20 W/m2.
Albeit the dB levels are the same, the references are different, that is, ref 2.6 x10-20 W/m2in seawater, differs from ref 10-16 W/m2in air, and therefore, one deduces that the human ear is better suited for sensing Sounds in the Air than it is for Sounds in the Sea. Neither is the comparison below veritable, in that the minimum sound-pressure level sensed by the human ear in air is not comparable to the “zeroed” reference level for a modern ceramic transducer in seawater:
SPL air = 20 log10 [0.645 dyn/cm2] -20 log10 [0.0002 dyn/cm2] ≈ [-4 dB] – [-74 dB]
= 70 dB ref 0.0002 dyn/cm2 = 70 dB ref 20 μPa; and,
SPLseawater = 20 log10 [0.0645 Pa] -20log10 [1 x10-6 Pa]
= [(-24 dB) –(-120 dB)] = 96 dB ref 1 μPa, the difference of the references.
With respect to the sensitivity of the acoustical receptor, consider that an earlier design of a magnetostriction electro-acoustic transducer, a la a hydrophone, could be “zeroed” to 1 dyn/cm2@4ft as its pref in seawater. In comparison, today’s electrostriction electro-acoustic ceramic transducers can be “zeroed” to 1 μPa, which is 100000 times more sensitive, in that, 1 dyn/cm2 = 0.1 Pa = 1 x10-5 μPa, a technological advance of +50 dB ref 1 dyn/cm2.

Summation– with an example. Our binaural hearing system has a low threshold for sensing acoustic energy levels—within our sonic frequency-band. Moreover, we can discern relatively small changes in those incoming acoustic levels.
Patently, by advances in modern technology, ceramic electrostriction-transducers coupled with powerful digital-signal processors have much lower detection thresholds than we do just hearing through our ears; and, can discern much smaller increments of level-changes.
Some say, perhaps for marketing hype, that their hearing-assisted amplification devices can sense, “hear,” a sparrow’s heartbeat across the street. Nonetheless, there are devices that can “hear” normal conversation inside a room from across the street—or, from a helicopter patrolling overhead.
In regard to measurement, it is somewhat more difficult [more $$$] to measure changes in sound-intensity, or sound-power levels, and record the SIL in dB for the respective I, than it is to measure changes in sound-pressure, and simply note the SPL in dB as indicated on the meter-face for the impinging p. Similarly, dB can be measured for reciprocatory transducer voltages, as referenced to the electro-mechanical measuring instrument’s “zeroed” setting for a MDS.
 Practically, SPL in dB is the preferred measurement for Sounds in the Sea.
To close with an intriguing example of a somewhat foreboding man-made sound …in the Sea, consider a coal-oil powered [diesel-electric] submarine-warship running submerged at about 200 feet making 170 RPM [≈8 knots]—and, radiating broadband noise from water-cavitations caused by the thrashing rotation of the ship’s propulsion screws.
Markedly though, the processed sound-pressure spectrum peaks at about 28 dB ref 1 dyn/cm2@ 4 ft, and is centered around 1-kHz. This SPL dB equates to p seawater of 2.55 x 101 dyn/cm2. Its SIL dB is comparable to 102 dB ref 10-16 W/m2 in the air at the passenger-platform as the subway-express passes through the station; whereas, the I air for the subway-express is 1.58 x 10-6 W/cm2.
Notably, 102 dB ref 10-16 W/m2 is just -3 dB “down” from 105 dB ref 10-16 W/m2, the sound-intensity level at which the US Navy requires the donning of double-ear protection.
Q: Is that close enough for government work, or is it a doubling of the sound-intensity?
A: Well now, you know precisely how much that is, to wit: 2∙(1.6 x 10-16 W/m2). qed.

Most importantly: Always note the dB reference for Apple-to-Apple comparisons. ▄


[Note: For I W/m2 = p2/ρ0∙c air, where ρ1∙cair = 41.15 N∙s/m3; and, p ref = 1 dyn/cm2 @ 4 ft for SPL dB.]
Sound SIL dB I in p in SPL dB
Type ref 10-16 W/m2 W/m2 dyn/cm2 ref 1 dyn/cm2 @ 4ft
Saturn Rocket 194 2.4 x103 1.01 x106 120
Flight Deck Ops 140 1.0 x10-2 2.04 x103 66
Excruciating Pain 130 1.0 x10-3 6.45 x102 56
Missile Tube Vent 120 1.0 x10-4 2.04 x102 46
Rock Concert 115 3.2 x10-5 1.14 x102 41
Marine Diesel 110 1.0 x10-5 6.45 x101 36
Radial Saw 105 3.2 x10-6 3.68 x101 31
Subway Express 102 1.6 x10-6 2.55 x101 28
Paint Chipper 100 1.0 x10-6 2.04 x101 26
Lawn Mower 95 3.2 x10-7 1.14 x101 21
Niagara Falls 92 1.6 x10-7 8.08 x100 18
Shouted Speech 90 1.0 x10-7 6.45 x100 16
Forklift 85 3.2 x10-6 3.68 x100 11
Conversation 70 1.0 x10-9 6.45 x10-1 -4
Average Office 55 3.2 x10-11 1.14 x10-1 -19
Average Home 40 1.0 x10-12 2.04 x10-2 -34
Rustling Leaves 20 1.0 x10-14 2.04 x10-3 -54
Quiet Whisper 18 6.3 x10-15 1.62 x10-3 -56
MAF reference level 0 1.0 x10-16 2.00 x10-4 -74
Sample Calculations:
SIL dB = 10log10 [1.6 x 10-6 W/cm2] –10log10 [1 x 10-16] ≈ [+2 dB -60 dB] –[-160 dB] = 102 dB ref 10-16 W/m2.
SPL dB = 20 log10 [2.55 x 101 dyn/cm2] -10 log10 [1 dyn/cm2] ≈ [+8 dB +20 dB] –[0 dB] = 28 dB ref 1 dyn/cm2 @ 4ft.
P W/mo2 = p2 ÷ ρ1∙cair = [(2.55 x 101 dyn/cm2)2 x 10-3 x 10-4] ÷ [(41.1551 N∙s/m3)] = 1.580 W/m2; where,
ρ1∙cair = 41.1551 N∙s/m3 is for the extant air-density in the subway-express station at the time of measurement.

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Submarine Modernization: On 4 July 2004, USS VIRGINIA (SSN 774) joined the Fleet.  She is 377 feet in length, 34 feet in the beam, has a draft of 30.5 feet at the designer’s waterline, DWL, and displaces 7800 dwt submerged.  She is designed with Berthing and Messing to accommodate 14 officers and a crew of 120.


VIRGINIA’s Length-to-Breadth, L/B, ratio of 11.09 is comparable to the 11.0 for LOS ANGELES Class submarines with a 33-foot beam, and is somewhat more than SEAWOLF’s 8.4 with a 42-foot beam, but a little less than OHIO’s 13.3 also with a 42-foot beam.

Note that the US Navy officially will neither confirm nor deny any US submarine’s speed except to be greater than 20 knots, and a test-depth greater than 400 feet.

The wall-thickness and diameter of VIRGINIA’s cold-rolled, HY-120 steel inner pressure hull, with scrupulously designed hull-penetrations and conscientious seam-welds, allows submarine design engineers to impose a safe-diving test-depth of 1600 feet, according to the open literature. Her design for a reduced number of needed hull-penetration features eight non-hull penetrating antennae packages.

VIRGINIA is powered by a S9G PWR, a Pressurized Water Reactor, made by General Electric that will not require re-coring for the life of the ship.  Her propulsion plant is rated at 40,000 SHP for a single shaft with a maximum rated submerged speed of 34 knots, according to the open literature.  She is designed with SEAWOLF-level acoustic quietness for stealth as well as acoustic tile cladding for active acoustic signal absorption.

VIRGINIA’s integral 9-man lock-out chamber can be used with the Advanced SEAL Delivery System, ASDS, which is mini-submarine capable of “dry” delivery of a SEAL team.  Moreover, the internal torpedo magazine space can be adapted to provide 2400 cubic feet of space for up to 40 SEAL team-members and their equipment.

VIRGINIA is capable of carrying and operating advanced Unmanned Underwater Vehicles, UUV’s, wake-homing detection equipment, and a deployable active bi-static sonar source.

The bottom-line is that VIRGINIA is an extremely capable submarine, and in the hands of a well-trained, experienced ship’s company skilled in the operational arts of submarine warfare, has an incisive ability for both deep ocean and shallow water operations of all kinds— including Anti-Submarine Warfare.

But, of all the technological advances of the 20th century, electrical and electronic ones top my long list of amazing achievements.  On my military-related list of amazing achievements, there are two technological advancements that stand-out to me.  One is for the technological improvements in the electronic instruments for precise navigation, and the other is for the advances in military command-control-communications.

Navigation:  The Art—and, the Science. Some 439 years after Magellan’s historic circumnavigation of the world on May 10, 1960, USS TRITON (SSRN 586) completed the first submerged circumnavigation of the world following Magellan’s route having sailed some 41,000 miles in eighty-four days.

Two years before, NAUTILUS accomplished a historic navigational feat by transiting 1,830 miles submerged in four days from the Pacific to the Atlantic—and, in doing so, became the first ship to pass over the North Pole—NAUTILUS 90-NORTH!

On July 20, 1960, while submerged off the coast of Cape Canaveral, Florida, USS GEORGE WASHINGTON, with a self-contained navigational system for precise launch-position fixing fired two Polaris A-1 missiles that hit their respective bull’s eyes some 1200 miles down range, and then signaled: “FROM THE DEEP, POLARIS ON TARGET—RABORN.”

So, for comparison to these early strivings for more precise navigation on the open sea, consider the most sophisticated state-of-the art computer data processor now known, which precisely calculates the output of an absolutely ingenious arrangement of gyros and accelerometers that sense the slightest nano-scale movement: The SINS, Ship’s Inertial Navigation System.

But, in my biased opinion, at the top of the list are the technological advancements resident in the Common Submarine Radio Room, CSRR, for a US submarine to be in constant communication with its Submarine Operating Authority while submerged at sea anywhere in the oceans of the world.

Communication:  The Science—and, the Technology. For historical comparison of technological advances, note that the first nationally authorized submarine warship was not officially commissioned until 1900, while the first transatlantic radio-telegraph was not operational until 1901.  Moreover, it was not until some fifteen years later on May 31, 1916, that the British Grand Fleet engaged the German’s High Seas Fleet in the Battle of Jutland in the North Sea just off the Danish Peninsula of Jutland.

A bold German Admiral, Reinhard Scheer, led the German Fleet out of Helgoland Bay, through which 20 years later would be the western approaches for the Kiel Canal.  Admiral Scheer intended to break Britain’s blockade of Germany.  British wireless-radio monitors, acting as communication-intercept operators, diligently alerted Admiral Sir John Jellicoe with their timely intercepts of German command messages that were directing naval activity at Wilhelmshaven.

Admiral Jellicoe immediately ordered the British Fleet to sea, and the battle was joined at sea about 80 miles west of Jutland.  Rifled naval guns, 12” in diameter, fired 1000-pound projectiles with 400-pound powder charges that screamed at a muzzle velocity of about 1500 mph to strike targets over-the-horizon at a range of some 11 miles.  Naval warfare for the 20th century opened dramatically with the first act of “Shock and Awe.

Notwithstanding the advent of coal-powered, steam-engine driven, steel-framed and steel-clad DREADNOUGHT battleships, fast cruisers, expendable destroyers, et al, one of the most significant transpirations for naval warfare in WW-I, in my opinion, was the first use of radio-telegraphy communications to all the ships at sea; and, its concomitant intelligence nemesis, COMINT– communication intercepts.

Militarists profess that the ability of the German Naval Command to communicate directly with U-boats at sea greatly enhanced their successes in both WW-I and WW-II.

And, so it is today.


The Common Submarine Radio Room, CSRR. VIRGINIA’s modern communication suite installed as a CSRR is well-suited for the worldwide battle space of the 21st century.

A modernized Ship Self-Defense System, SSDS, will replace the Advanced Combat Direction System, ACDS, in VIRGINIA-Class upgrades.

All the software programs for the CCSM, Command-Control System Module, in VIRGINIA are compatible with the Joint Military Command Information System, JMCIS. For instance, the AN-USC-38 EHF transceiver in VIRGINIA has LINK-11 and NATO LINK-11 compatibly programmed for JTIDS.

The AN/WSC-8, Challenge Athena, houses a “Commercial Wide-Band Satellite Communication’s Program” to support the Tomahawk, Submarine Launched Cruise Missile, SLCM, land-attack configuration.

The AN/USQ-123 (CDL-N), Command Data Link, Navy, is used for receipt of signal-and-imagery intelligence data from remote sensors, and for the transmission that links sensor-control data to/from airborne and submarine platforms.

The Global Command & Control System, GCCS, is a multi-service information management system for maritime users that can display and disseminate data through an extensive array of common interfaces.  GCCS also is a multi-sensor data-fusion system for command analyses and decision-making.  Thus, in the main, it is utilized for overall force-coordination.

The Ocean Surveillance Information System, OSIS, receives, processes, displays, and disseminates joint-service information regarding fixed and mobile targets on land and at sea.

The Multi-Level Security System, MLS, also known as “Radiant Mercury,” among other things MLS automatically sanitizes highly classified data, and then re-issues it as SI-GENSER RELEASABLE to “Shooters” while still protecting sources and methods, national sensitivities, and foreign release-ability of the tactical picture.

The innovative design of the upgraded Automated Digital Network System encompasses all RF circuits for routing/switching of both strategic and tactical C4I, Command-Control-Communication-Computer Information, with TCP/ICP, Transmission Control Protocol/ Internet Control Protocol, thereby linking Battle Group units with each other and with the DISN, Digital Information System Network.

The ADNS now has 224 ship-based units, and four shore-based sites.  Network operation centers are linked to three Naval Computer and Telecommunication Area Master Stations plus one in the Persian Gulf at Bahrain.  Whereas, the Global Broadcast Service, GBS, is the follow-on for US Navy UHF radio communication via satellite.  By 2009, the Advanced Wideband System, AWS, will be the communication upgrade for all US submarines and surface ships, and a version planned for US aircraft installation is under study.

Submarine Tasking. So, what are submarines task to do?  Primer: Submarines Sink Ships!

Second to that, submarines can hunt and kill other opposing submarines in the medium with them.  In more poignant warfare scenarios, submarines can be tasked to mine sea-lane choke points as well as enemy harbors.  Moreover, pursuant to mission accomplishment in support of national policies, and in particular for a duly delineated national armed-force objective to “Project National Power,” submarines can launch land-attack missiles from international waters, as directed by the National Command Authority, NCA– acting unilaterally.

In addition, submarines can be tasked to conduct surveillance and reconnaissance operations inside and outside the battle space, covertly.  In that same vein, submarines can be tasked to insert, and, or retract Special Operating Forces on the shores of the world’s ocean-littoral– covertly.

For deployments, submarines provide indirect, associated, and direct Battle Group support.  Time-On-Station for modern nuclear-powered submarines is dependent only on the amount of food they have to feed their crew—like 90 days without replenishment.

Note, after 60 days, dreams of a real milk-shake, and a … become more frequent, seemingly with an exponentially increasing persistency.

As a precursor for a discussion on submarine weapons, consider the following “insider” information about sensing an acoustic event—as heard from each side.  The sound of flooding a torpedo tube with a weapon in it is a distinguishable acoustic event.  In an analogy to Blind Man’s Bluff, this is the sound-equivalent of the sight of a pistol being drawn from its holster.  Likewise, hearing a torpedo tube’s outer door open is analogous to seeing a pistol’s hammer being cocked.  Doubtless, these are distinctive sounds that are instinctive indicators that you are engaged in mortal combat, a fight—a gunfight.

Note that at sea, water from below, like water from above, wets both teams.

Submarine Weapons. The Mark-48 Mod-6, Advanced Capability, ADCAP, Heavyweight (heavier than the water it displaces) Acoustic-Homing Torpedo, is an automated marvel of essentially an unmanned underwater vehicle that delivers an explosive charge as a very “numbing sting.”

The ADCAP is self-propelled by an axial-flow, pump-jet propulsion system driven by an external combustion, gas-piston engine fuel-fired by a mono-propellant, Otto Fuel II. There are two run-speed selections: LOW, for 40 knots and a range of 50 km; and, HIGH, for 55 knots and a range of 38 km.  The MK-48 is 228” in length and 21” in diameter weighing in at 3527 pounds, which is about 600 pounds heavier than the sea-water its volume displaces.  Its warhead is 590-lb of High Explosive, with a 1.5 multiplying factor for its TNT-equivalent.

Note, from the perspective of the target, sensing this torpedo coming at you is analogous to you finding yourself driving precariously on an icy road in the middle of nowhere, and then alarmingly you sight through your driver’s-side window a pick-up truck barreling down on you at about 63 mph– loaded with 900 sticks of dynamite.

From this visual input, you analytically conclude that you have less than a minute in these icy conditions to think and act to avoid collision—and thus, realize that the only thing you have time to do is bend over and kiss yourself good-bye.

The submarine-launched Tomahawk Land-Attack Missile, TLAM, has a range of 900 km with a 1000-pound High Explosive warhead.  With a Terrain Contour Matching Aided Internal Navigation System, TAINS, its circular-error probable, CEP, is inside 10m for 50% of its shot-trials—like in through your front-room’s window instead of knocking on the front-door.        

Submarine Combat System. VIRGINIA’s combat system is a suite of very high-tech devices that each satisfy a Mission Essential Need. The suite has devices designed to sense danger—and opportunity.  These devices are a very effective set of acoustic sensors.  There is a reel-able linear towed array sonar, and a thin-line array—TB-16 and TB-29. Just inside the thin-skinned acoustic “window” of the outer hull around the bow is a very sophisticated, state-of-the-art active/passive spherical sonar array, AN-BQQ-5E.  In addition, there are wide-aperture flank-mounted passive arrays, AN-BQG-5D; a keel-and-fin-mounted high sonic frequency active sonar for under-the-ice ranging and maneuvering as well as for mine detection and avoidance; a medium sonic frequency active sonar for target ranging; a sonar sensor for intercept of active-ranging signals from an attacking torpedo; and, a self-noise acoustic monitoring system.  Moreover, all acoustic systems have advanced signal processors– replete with programmed algorithms for beam-forming.

Electronic System Measures, ESM, include the AN-BRD-7F Radio Direction Finder; the electronic signal monitors, AN-WLR-1H, and AN-WLR-8(V) 2/6.

The ESM suite also includes AN-WSQ-5 and AN-BLD-1 Radio Frequency Intercept Periscope-Mounted Devices, AN-WLQ-4(V) 1, AN-WLR-10, and AN-BLQ-10 Radar Warning Devices. Active electro-magnetic devices in this suite are the AN-BPS-15A and BPS-16 are I- and J-Band navigational piloting radar respectively with a waveguide mounted in a retractable mast, and a waveguide mounted in a periscope.

The Combat Data System, CDS MK-2, has an AN-UYK-7 computer-data processing unit.  IBM’s AN-BSY-2 is a re-designed combat system from the decade-earlier one in SEAWOLF.  VIRGINIA’s “Busy-Two” is reprogrammed with 2.2-million lines of ADA code loaded in some 200 Data Processors, AN-UYK-43’s and UYK-44’s.

This CDS manages input from an integrated digital upgrade of the AN-UYS-2 Acoustic Signal Processors with their Expanded Directional Frequency Analysis and Recording System.

The Torpedo Fire Control System, TFCS, is on a high-speed data bus with a distributed architecture for redundancy.

The TFCS is programmed with advanced algorithms for Target Motion Analysis, TMA, and is operated from multi-function consoles that also are used for information management.

Target Motion Analysis—the Relative Motion Triangle:

A Bearing versus Time

Plot—to determine Bearing-Rate.

TFCS Stick Diagrams– in the minds of submarine officers.

Shallow water is an anathema for submariners because submarines on the surface are exceptionally vulnerable.  Thus, it is said that the best place to sink a submarine is while it is in port.  Does that mean that VIRGINIA cannot operate effectively in shallow water?  Absolutely not!  Are VIRGINIA’s submarine officers aware of the “shallow water” effects when operating within 238 feet of the bottom—seven times the “height” of her displaced volume– and, by geometry, when in 125 feet of water, a 20-degree diving angle will result in “kissing” the bottom?  Of course, they are—we bought them books, and sent them to school.  In a deadly analogy, be aware that a shark can attack you as you wade in shallow water.  Sic ‘em, ‘Ginia!

Another disconcerting imprecation to submariners is hearing the “pings” of active sonar followed by the shrill of small, high-speed, super-cavitations screws, which are the distinctive sounds of an acoustic torpedo running to …ruin your entire day.

French author Jules Verne, 1828-1905, entertained us with exciting tales of undersea adventure featuring his fictional submarine Nautilus in his book “20,000 Leagues Under the Sea.”  Notably, our USS NAUTILUS (SSN 571) logged much more than 80,000 nm—20,000 leagues—under the sea before her first re-coring; and, VIRGINIA will log over 125,000 leagues of submerged steaming in her service life, without refueling.

The nuclear-powered submarine is a far-ranging, very effective, versatile warship for the 21st century—and, the Projection of National Power only requires unilateral action by our NCA. Seemingly, We, the People, still hold some Truths to be self-evident …that among these are Life, Liberty, and the Pursuit ofall those that threaten us.  Our battle flag once warned, as did our Navy Jack for a year in 1976:

Don’t Tread On Me!

The Threat: The Enemy BelowA German Type 214 AIP Submarine.

The Type 214 is 213 feet in length with a submerged displacement of 1860 dwt.  They are equipped with two 120-kW Siemens AIP, Air-Independent Propulsion, fuel-cell power units, as well as two 1,000-kW diesel generator sets.

The first of four Type 214 submarines for the Greek Navy, the Papanikolis, is pictured above just after delivery and christening at Howaldtswerke Deutsche Werft (HDW), Kiel, on 22 April 2004.  The Papanikolis will be followed by three sisters on order from HDW’s subsidiary Hellenic Shipyard at Skaramanga, Greece, namely, the Pipinos, Matrozos, and Katsonis. The Pipinos is planned to complete in September 2005.  Currently, three of Greece’s four German Type 209/1200 submarines also are being back-fitted with fuel-cell AIP during refits ordered in June 2002.


Portugal ordered two German Type 209-PN submarines on 21 April 2004.  These submarines too will have Siemens AIP systems installed as well as their original diesel-electric generator sets.  The first of these is to be delivered in 2009, and the second a year later.  Both are estimated to bill at $490-million each.  Apparently, the pair is intended to replace two vintage-1960 French-made Daphne Class boats, which are to be retired in 2006.

In mid-July 2004, a photograph of a submarine underway on its own power standing out from China’s Wuhan shipyard—some 420 miles inland from Shanghai—was posted on a Chinese Internet site.  The following is a paraphrasing of an article published in The Washington Times as written by Bill Gertz on July 16, 2004.

Reportedly, a US DOD official confirmed that the photographed submarine is the lead ship of China’s new YUAN-Class submarine.  Its design can be categorized as a combination of indigenous Chinese hardware and Russian weapons.

The PRC’s public exposure of this new class of submarine leads some US defense analysts to opine that China may be building up its naval forces in preparation for an armed confrontation with the US-supported ROC on Taiwan.

These US analysts suggest that Chinese militarists may have decided that submarines are the PRC’s first-line of warships for defying US aircraft carriers.

Moreover, China also is building two nuclear-powered submarines—one Type 093 fast-attack submarine similar to the Russian VICTOR-III Class, and one Type 094 intercontinental ballistic missile submarine—which should be ready for deployment next year.

It is believed that in the coming months the US will continue to strengthen naval forces in the Pacific by the forward deployment of up to six additional nuclear-powered submarines to Guam, and an aircraft carrier naval battler group to the South China.

Unlike the quotes attributed to Mister Richard Fisher, the outspoken former White-House advisor and now billed as a “Specialist” on the Chinese military, my take is more like one from a warfare realist:

In God We Trust

But We Track All Others!


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The Advent of Submarine Warfare

The Advent of Submarine Warfare.  The epoch for Submarine Warfare, for all intents and purposes, opened with the brusque plume of an exploding torpedo launched by a German U-boat sinking SS LUSITANIA, a British passenger liner, off the southwest coast of Ireland on May 7, 1915, leaving 1154 dead, including 114 Americans.[1]

Patently, the submarine evolved from a very awkward beginning into a very versatile, very stealthy, and very cost-effective warship.  The following Benefit-to-Cost, B/C, analyses compare the costs of ships sank by warships to the costs of those warships lost in the effort.  Statistically, this B/C portrays the efficacy of the submarine warship as a very cost-effective, ship-sinking interdictor of ocean sea-lanes.

In WW-I, German U-boats sank 5,708 merchant ships, and 62 warships.

To absorb the magnitude of those numbers, you may have to read them twice-over so as not to trivialize their significance—or, their economic significance.  These sinking numbers equate to some 11,018,865 dead-weight tons (dwt) of steel in merchant-ship hulls plus their consigned cargo, and 538,535 dwt of warships.  Figuratively, and literally, that’s a colossal “sunk cost.”

This sunk cost can be estimated parametrically to be $39.4-billion—at the time-value of money for 1918.  Then, dividing that “Benefit” by the “Cost” of the lost of 178 U-boats estimated parametrically to be $1.3-billion, yields a B/C ratio of 30.5!

Notably, a B/C of 1.0 is breakeven, doubling your money is 2.0, and 4.0 is considered a beneficial venture.

There was a lot to be learned in the two intervening decades between WW-I and WW-II.  Ardent studies of the technologies and techniques associated with Anti-Submarine Warfare (ASW) were lessons that had to be learned by the “Hunter,” and the “Hunted.”

Inevitably, as if portended by the foreboding Winds of War, German U-boats in WW-II sank 23.4-million dwt of allied shipping plus their cargo, which together is estimated to be $78.5-billion.  Dividing that by the lost of 781 U-boats estimated to be $5.7-billion yields a B/C of 13.8.

In comparison to the greater B/C ratio in WW-I, one deduces that ASW in the Atlantic apparently helped to cut this telltale ratio by more than half.  I doubt though that this lesser B/C was any solace to those having to stomach the lost of $78.5-billion– at the time-value of money for 1945.

Meanwhile, On the Far Side, how did US submarines fare in WW-II against the Eastern island empire of Japan in the Pacific?

US submarines sank 4.9-million dwt of Japanese warships, and merchant ships plus their cargo, which together is estimated to be $16.3-billion.  Dividing that Benefit by the Cost of the lost of 52 US submarines materially estimated to be $355.3-million yields a B/C of 45.9![2]

At the beginning of 1943, as another statistical example, over the sea-lane between Taiwan and the Philippines at the Bashi Channel choke-point for the Luzon Straits connecting the South China Sea with the Philippine Sea, Japanese oil-tankers were transporting some 1.5-million barrels of crude oil per month for Japan’s refineries to make distillate fuels for their war-machines.  That sea-lane was interdicted by US submarines, literally torpedoing Japan’s oil-imports.  By the end of 1944, this crude-oil supply had been reduced by 80 percent to something less than 300,000 barrels per month.

US submarines, with only 2% of all US Navy personnel, were credited with sinking 55% of all Japanese merchant ships, and 29% of all Japanese warships.

This era of submarine warfare, however, is still a “work-in-progress.”  It began auspiciously on May 7, 1915, when a German U-boat torpedoed and sank SS LUSITANIA off the southwest coast of Ireland.  For the moment, its log’s tab is set on May 21, 1982, when a British nuclear-powered attack submarine, HMS CONQUEROR, torpedoed and sank Argentina’s battle cruiser BELGRADO off the Argentine coast in the approaches to the Falkland Islands—a 150-year-old British colony that occupying Argentine armed forces two weeks later surrendered back to British armed forces on June 4, 1982.

The lead-in photo for this closing is a subtle depiction of the forebodingness of Submarine Warfare for several significant reasons.  It could be said to be a chilling photo because it is of a submarine warship entering a German port.

In 1936, Chancellor Adolf Hitler officially opened the Kiel Canal, and relegated the inaugural passage to one of Der Kriegsmarine Unterseebooten. So, the Third Reich’s construction of the Kiel Canal may have been for other means to bolster Germany’s maritime economy.


Thus, HARDER’s transit of the Kiel Canal at the end of Kieler Woche could be deemed to have been some surrealistic scheme to top-off the Kiel Canal’s twenty-fifth anniversary with a transit of a Type XXI U-boat.  But perhaps, I just consider this photo to be significant because I am the young submarine officer pictured on deck with the Anchor Detail as HARDER stood in to Kiel that day.  Nevertheless, it remains:

Submarines Sink Ships!

[1] Notably, in 1916, the year after a U-boat sank SS LUISITANIA, USS E-1 (SS 24), which was 135 feet in length with a submerged displacement of about 400 dwt, became the first submarine to cross the Atlantic under her own power, that is, the first trans-Atlantic crossing by a coal-oil-powered submarine.

[2] Notably, this B/C was higher than that for German U-boats because by my deductive reasoning the US tactics of submarine approach and attack were with more stealth, and that ASW by the Japanese Navy was less intense and less effective.

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The Evolution Of The Submarine As A Warship

THE EVOLUTION OF A SUBMARINE—AS A WARSHIP. At the close of the 19th century, the hail heard around the world was Britannia Rules the Sea. Ships of the Royal Navy were high profile targets for their enemies—both foreign and domestic.

Douglas Porch, in his book The Path to Victory published in 2004, by Farrar, Straus, and Giroux in New York, revealed that Irish revolutionaries in 1876, known as the Fenian Brotherhood, contracted John P. Holland, an Irish-American who had immigrated to the US in 1872, to develop a way to sneak up on British ships from underwater, and sink them.

Holland’s work began in Paterson, New Jersey, on the Passaic River, and then moved to New York harbor. The Fenian’s, however, withdrew their support of Holland’s research when he failed to meet their timetables. Private investors though kept Holland afloat. By 1898, Holland had produced his sixth prototype—and, the US Navy was ready to buy. On April 11, 1900, the US Navy purchased Holland-VI for $150,000; and, for the record, the US Navy Submarine Force was born. Then, on October 13, 1900, USS HOLLAND (SS 1) duly was commissioned, Lieutenant H. H. Caldwell, US Navy, Commanding.


HOLLAND was 53.3 feet overall, with a maximum beam of 10.3 feet, a cruising draft of 8.5 feet, and a submerged displacement of 75 deadweight tons, dwt. HOLLAND was constructed with fitted steel-plate attached to angle-iron rib-frames that had been forged into perfect circles starting at 10.25 feet for the central one, and then decreasing to end-closures to form a parabolic, spindle-shaped hull. Safe test-depth was set at 80 feet to correspond to an external, water-head, crushing pressure of 35 psi, pounds-per-square-inch.

HOLLAND featured an ingenious dual-propulsion system. A 50-horsepower Otto (gasoline) engine was geared to drive a propulsion-screw– a propeller– directly, or by a friction clutch could be connected as a dynamotor for charging HOLLAND’s electric battery. This battery then could be switched to provide electrical energy to an electric motor that by friction clutch could be connected to the propulsion shaft.

HOLLAND’s maximum speed on the surface by gasoline-powered engine was rated at 7 knots; and, when topped-up with fuel, HOLLAND had an endurance-range of about 1500 nautical miles, nm, at her engine’s maximum continuous rating for making turns for 7 knots. When submerged, HOLLAND’s fully charged battery discharging at the six-hour rate had the ampere-hour capacity for electric motor propulsion at a rated maximum submerged speed of 5 knots for a submerged endurance-range of about 30 miles!

And, to go in harm’s way, HOLLAND had a single internally loaded 18-inch diameter tube that extended through the pressure hull in the bow for launching the new, improved Whitehead diving-torpedo Mark-III that was 11.65 feet in length, and rated at 30 knots for a run of 2000 yards. Moreover, HOLLAND was designed with space-and-weight accommodation for two torpedo reloads. Submarines were now stand-off warships.

Submarine Weapon Development.  The British, however, lagged in early submarine development.  The Admiralty apparently thought submarine attacks were dishonorable; and, declared that captured submariners would be treated as pirates, and be hanged, accordingly.

After Britain’s rivals at sea commissioned Holland to build submarines for them, the Admiralty changed its tune.  As what could be expected, Holland later profited from selling submarines to that same Admiralty whose fleet he once had been paid to sink.

It is interesting to note that it was the US inventor Robert Fulton who in 1805, after studying the design of Bushnell’s Turtle, positively demonstrated in a weapon-trial the feasibility of sinking a ship by detonating an explosive charge against its underwater hull.

Some sixty years later in 1866, two years after the submarine CSS H. L. HUNLEY was lost detonating a torpedo attached to a bow-sprit spar that sank USS HOUSATONIC in Charleston harbor, Robert Whitehead, a Scottish inventor, demonstrated his advanced development model of an auto-mobile torpedo—to the Germans.

At the behest of officials representing the German Kaiser’s government in Austria, Whitehead demonstrated an unmanned, underwater vehicle that was a self-propelled, lighter-than-water dirigible—a “diving submarine.”  It essentially was an automated-mobile—an auto-mobile—underwater vehicle that could deliver a “numbing” explosive charge—a torpedo—to detonate against the underwater hull of a target-ship, and sink her—from a stand-off distance!

As the world turned into the 20th century, a booming Industrial Revolution seemingly elevated science and technology as if they were its King and Queen, their supreme overseer.  It was like there had been a royal Coronation of Science & Technology.

Figuratively, a silver spoon was placed in the mouth of each new steamship born in modernized shipways.  They indeed were capital-intensive assets.  This was Big Time financing.

With the continuing evolution of submarines as reliable warships, torpedo advancements burgeoned to keep pace with them.  For instance, by the onset of WW-I, US submarines had the new Bliss-Leavitt Mark-X torpedo, which weighed in at a hefty 1,628 pounds with a 326-pound warhead, stood 17.1 feet in length with an 18-inch diameter-girth, and ran 6,000 yards (3 nm) with a rated speed of 35 knots.

Now, enter the most efficient, the most cost-effective, the most peerless shipping interdictor, the most devastating business-loss inflictor, and most menacing national economic strangler of them all:

Der Kriegsmarine Unterseebooten!

The Enemy Below. During WW-I the word “U-boat” entered the world’s lexicon as a contraction of Unterseeboot, the German labeling of their new submarine warships. U-boat also entered the world’s consciousness as an offensive instrument of warfare that devastated commercial shipping.

Contrary to popular belief, the crews of Germany’s feted Ubootwaffe were not all volunteers.  Once committed though, each German submarine-sailor soon came to understand that he must take pride in being a member of a unique undersea brotherhood.  Thus, the sailors of this brotherhood– this Ubootwaffe– became bound together by an intense camaraderie, by ever-present dangers, and by a unity of purpose more powerful than any known to other sailors.

So, with over-extended capital investments, the British built new, capital-intensive, ocean-going steamships to bolster their colonized trade—strategic imports—from overseas.  The strategic plan of the Germans—Britain’s “new” continental rival– was to interdict British capital-intensive, economic assets that sailed those seas, and do so with stealth and surprise from a hidden position just below the surface of the sea.

Germany set about to build and crew cost-effective U-boats whose individual tactical ship-sinking combats could be managed strategically to achieve their national goal of Economic Equality with their rival Great Britain.  These U-boats were armed with a German version of an advanced Whitehead torpedo that very effectively—very cost-effectively– delivered an explosive charge to a target-ship at a stand-off distance that typically was less than half a mile even though the torpedo had a maximum run of three miles.

These U-boats featured a dynamo with an innovative design of an internal combustion engine that was not fueled with gasoline—and, did not require an ignition system.  Thus, this “rational heat engine” was more efficient, and safer, than gasoline-fueled ones.




In 1897, after a major re-design of the lubrication system for this coal-dust fueled, single cylinder, four cycle pump-engine for flooded mineshafts, the first successful engineering development model of a liquid-fueled, “coal-oil,” engine was completed by its then-bankrupt inventor in collaboration with the Krupp firm and an Augsburg-Nuremberg machine shop, Maschinefabrik Augsberg Nürnburg– MAN.

Some fifteen years later, in 1912, a year before the death of the engine’s impoverished inventor, the US Navy procured a number of them from New London Ship and Engine Company, NELSECO, teamed with Vickers– a British shipbuilder licensed by this German conglomerate.  These engines were the coal-oil fueled, four cycle version having four cylinders with a 12.75-inch bore and a 13.5 stroke that were rated 275 BHP @400 RPM.  They were scheduled for installation in E-1 Class (ex-SKIPJACK) US-submarines to replace the scheduled gasoline-powered prime movers for the dynamos in their dual-propulsion hybrid system.[1]

In 1908, the German Navy favored the lighter (pounds-per-horsepower), two cycle version; but, in preparatory expediency for their inevitable war plans, they proceeded to fit all their U-boats with a six-cylinder, four cycle version of this now-feted engine as designed by its fatherly inventor whose name they bear– Rudolf Diesel, 1858-1913.

The rest of the story is legendary.

Diesel Boats Forever!


[1] Notably, on March 5, 1912, a month before SS TITANTIC sank, President Taft established the Atlantic Submarine Flotilla– Lieutenant Chester W. Nimitz, US Navy, Commanding.

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TORPEDOS LOS! -The Efficacy of Submarine Warships.

SUBMARINE TASKING. Pursuant to mission accomplishment in support of national policies, and in particular for a duly delineated national armed-force objective to “Project National Power,” submarines can be tasked to launch land-attack cruise-missiles from international waters– as directed unilaterally by our National Command Authority, NCA.

Submarines can be tasked to conduct surveillance and reconnaissance operations inside and outside the battle space, covertly.  In that same vein, submarines can be tasked to insert, and, or retract Special Operating Forces, SOF, on the littoral shores of the world’s oceans– covertly.

In more poignant warfare scenarios, submarines can be tasked to mine sea-lane choke points as well as enemy harbors.

Moreover, and perhaps most particular, submarines can hunt and kill other opposing submarines in the same undersea medium with them.  Besides the deep ocean, that undersea medium includes the shallow waters for our coastal defense as well as that for projecting US national power by amphibious forces in foreign waters.

Notwithstanding the brassy jingoism above, submarines were first procured to sink threatening warships by surprising them from below the sea with the numbing sting of a torpedo.  For over a hundred years now, submarines have been so tasked; and, since WWI, submarines have been tasked to interdict sea lanes and sink unarmed merchant ships to deny re-supply.  Yes, VIRGINIA, an economic strangler lurks in the seaSubmarines Sink Ships!

When SEAWOLFconceptualized in the painting above—was launched in 1995, there were some 24,000 merchant ships of over 1,000 gross-registered-tons plying the sea lanes of the world for international trade and transport.  For national comparison, a table of Merchant Fleets of the World, ranked by number of oceangoing vessels, is provided below delineating a grand total of their displacements as about 657-million dwt (deadweight tons).

As capital-intensive assets—meaning their annual amortized construction cost and operating expense well exceed the cost of labor to operate them—their collective loan-value, without any consigned cargo, can be estimated parametrically to total about $1.5-trillion.  Moreover, the annualized value of their consigned cargo that they deliver each year can be estimated to total about $3.0-trillion.

Ask yourself which of these national economies today could stay afloat with the sunk cost of its Merchant Fleet?

And today, with near instantaneous news around the world, when the first explosion from a submarine-launched torpedo plumes brusquely, so will ocean-shipping insurance rates.

In regard to fleet operations, submarines can be tasked to provide INDIRECT, ASSOCIATED, and DIRECT Battle Group support.  For deployments, Time-On-Station for modern nuclear-powered submarines is dependent only on the amount of food they must carry to feed their crew—like, a 90-day supply, without replenishment.

Some submarine-patrol stations literally are On the Far Side.  For instance, our forward submarine base on Guam in the western Pacific is about 12 days of submerged steaming from San Diego.  Then for a submerged transit from Guam to a patrol station in the Gulf of Oman via the Java Sea and the Lombok Straits thence across the Indian Ocean could take as long as 16 days.

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