Navigate by the Stars—From Beneath the Waves
Understanding celestial fundamentals, how bodies rise and set and move through the sky is a warrior skill. At Riverine Warfare School at Camp Lejeune in 2009, one exercise involved landing boats on a river bank and then patrolling several miles inland and south through dense mangroves, where water was waist-high. To make forward progress in a timed exercise, our squad had to keep moving at a fast pace. Following a compass course was impossible due to the circuitous route required to avoid obstacles and deep water. We used the star Canopus to guide us, which is always due south in the night sky in the Northern Hemisphere in winter months. We reached our required phase line ahead of schedule.
A few more observations: A proficient navigator uses a Rude Starfinder to precompute the best stars for sights based on brightness, azimuth, and altitude. Choosing appropriate stars before shooting enables navigators to obtain data for a fix in short order.
To take a noon fix with one sun line, first determine the time of Local Apparent Noon (LAN) using the Nautical Almanac and your course and speed. Use a stopwatch and your sextant to measure the sun’s continuous rise, commencing five minutes before LAN. Record the sun’s height (sextant reading) and exact time using a stopwatch. Use that time to compute longitude, and the sun’s height to compute latitude. For latitude, the formula is: latitude = (90 – Ho) +/- declination. I routinely computed latitude before departing the bridge wing.
I also routinely obtained fixes within a mile of our Loran A, Loran C, and GPS positions. Yes, Loran A. When I first went to sea in 1977, all we had for electronic navigation was Loran A and radar. Often radar and depth soundings showed my celestial fix more accurately than the Loran A, and in later years, more accurately than Loran C.
The moon can be used to obtain a line of position (LOPS) both day and night, as can Venus, Mars, Jupiter, and Saturn. On one voyage, we fitted our sextants with night-vision scopes. I was able to shoot stars in the middle of the night when there was no visible horizon by naked eye, but a well-defined horizon when looking through the scope affixed to the sextants.
—CW4 Michael W. Carr, U.S. Army (Ret.), Marine Warrant Officer
The book of Ecclesiastes, 1:9, says nothing is new under the sun. Or under the stars, for that matter. It is fascinating to read of celestial navigation being used to fix the position of one of the world’s most technically advanced vessels, a nuclear-powered submarine. The submerged navigator replicates Odysseus and Calypso of Homer’s Odyssey. Both the epic hero and the nymph-goddess were familiar with the use of the stars to navigate—the Great Bear, the Pleiades, Bootes, and Orion, which Calypso instructed to keep hard to port (Book 5). Phoenicians had long been using the stars to navigate. Vikings took observations of the sun to find their way across the open sea. Vast stretches of the Pacific Ocean could have been settled only by people with a profound knowledge of celestial movements. Celestial navigation predates literacy and systematic mathematics. The sight through the periscope is the same seen by navigators 100 generations ago. Enemies can disable electronic navigation systems, inertial-navigation gyroscopes can fail. Nobody can shoot down the stars.
—CDR Earl Higgins, USN (Ret.)
Having formerly served as electronics technician, navigation (ETV), on a Los Angeles–class submarine, I dabbled in celestial navigation. Many have tried to revive it, but it is perceived as too complex without prior training. To bring it back to the submarine force, there would need to be a significant push for its inclusion in the training curriculum (as a standalone school, I suggest) and a significant investment into development of hardware and software for periscopes and photonics-masts to detect stars with a precise measurement of altitude. A fix within 10 nautical miles is perfectly acceptable for open ocean navigation, but it can spell disaster for a vessel in a littoral environment.
In 2014, at the ETV A school in Groton, Connecticut, all we learned about celestial navigation was that the computer program Stella calculated celestial fixes. Once on the boat, practically the only reference for this was Dutton’s Nautical Navigation. Even after reading the applicable chapters, I might as well have been reading hieroglyphics if I wanted to apply the theory.
Ships and submarines are not static. They pitch and roll, get pushed off course, and so on. As Homeier noted, periscopes do not have near the degree of precision needed to receive high-quality celestial fixes. The environmental factors and imprecise measurements are together a recipe for a fix with a high degree of error.
Newer inertial navigation systems are supplemented with bathymetry data, and the quartermaster can take a bathymetric fix while at periscope depth or submerged. Because bathymetric fixes generally are more accurate than celestial fixes, we have tools that are better suited than celestial navigation.
That being said, I believe there is real utility for celestial navigation. To truly make it a useful, regularly used tool, some sort of computer vision could detect stars in the sky, take precise measurements, and compensate for environmental factors.
—ENS Tyler McGill, USN
This capability was available back in the 1960s. When the USS Halibut (SSN-587) was on post-overhaul sea trials, I was navigator. One quiet night as we cruised slowly at periscope depth, I decided to attempt a star fix using the sextant that was built into our no. 2 periscope. The skipper walked into control and asked what I was doing. When I told him I was having difficulty finding Aldebaran, he took the scope and muttered, “Aldebaran, Aldebaran. Let’s see; that’s in the constellation Taurus. It’s September. Should be about here.” Now, Hank Clay was one of the smartest guys I had ever known, and I’m sure he had not been a navigator for many years. He spun the scope to a certain azimuth and elevation and said, “Yup. Here it is.” As he walked away, it was now my head that was spinning. But I got the fix.
—CAPT James Ransom, USN (Ret.)
As one of the few nuclear-powered attack submarine (SSN) navigators who was disappointed in the early 1970s, when the periscope sextant was removed from the Type 15 and 8B periscopes, this article brought back many memories. I was a new construction navigator on the USS Trepang (SSN-674) and insisted that the periscope sextant be operational when we left the yard at Electric Boat, and that the electronics-technician (ET) division knew how to maintain the inner workings. The weak link was the data recorder, which had frequent problems.
In my day, you had to take about five or six shots as the periscope hairline passed the star or the lower limb of the sun or moon, and then take an average as the calculated elevation. Then it was all hand calculation that took hours. According to the article, an observation and calculation can now be done in minutes with computer programs. I suspect the author will find that the ease of that calculation will not be as great when he returns to sea from shore duty. I had to practice it at least once a week to maintain proficiency.
I was delighted that the Orion illustration was included. I used to shoot the stars in Orion when I had mid watches, and then calculate the potential fix after I got off watch. My best experience using celestial navigation was when the Trepang was on an ice trip and we were surfaced in a polynya at all-stop. The assistant navigator and I selected a time when a NAVSAT was passing overhead. We took sightings with the periscope sextant and the special bubble sextant topside simultaneously, with the NAVSAT fix. Both sun lines and the NAVSAT fix plotted right on the ship’s inertial navigation system (SINS) position. That was the only time that ever happened.
I hope all submarine navigators take this article to heart and practice celestial navigation, so that if ever necessary, they can successfully plot the submarine’s position by the stars.
—CAPT J. W. “Bill” Sheehan, USN (Ret.), Life Member
Use Bioluminescence to Own the ASW Night
This is a follow-on to RDML Donaldson’s and my October article. The new Constellation-class frigate can be the antisubmarine warfare (ASW) platform the Navy needs. The return of great power competition means carrier and expeditionary strike groups will not have the luxury of transits unmolested by submarines. Higher formation speeds can limit submarine effectiveness to a cone in front of the ships bound by “limiting lines of approach.” The area between the limiting lines of approach was traditionally searched by a line of ASW ships with bow-mounted sonar. However, to keep down the cost of the Constellation, the bow sonar of its parent frégate européenne multi-mission (FREMM) design was removed. Fortunately, a combination of manned and unmanned aircraft, all based on a single Constellation, can replace the previously required vanguard of ASW ships. An artificial intelligence–enabled swarm of 20 Scan Eagle–size unmanned aerial vehicles (UAVs) can visually, day and night, search a 20-kilometer-wide swath ahead of ships traveling at 20 knots.
A Constellation can expeditiously launch and recover a UAV swarm from multiple launch and recovery units on its upper missile deck. This will leave its helicopter hangars and flight deck free to operate a standard one-each hybrid MH-60R Seahawk and MQ-8C Fire Scout detachment. The MH-60R will cover the dawn and dusk periods, when there is not enough daylight for multi/hyper spectral imaging, or too much glare for bioluminescence detection. The Fire Scout will be on alert to deliver a torpedo, using the same visual sensors, to targets detected by the swarm beyond the range of antisubmarine rockets fired from the Constellation’s 32-cell MK 41 vertical launch system. If the Fire Scout cannot attack with lightweight torpedoes such as the MK 46 and MK 54, its parent company, Northrop Grumman, is among those developing a new, ultra-lightweight torpedo known as the compact rapid attack weapon-1 (CRAW-1). The Fire Scout should be able to carry many of these.
If the Navy applies these low-cost emerging technologies to the Constellation, it will have the quiet, low-cost (for both hull and crew), high-return-on-investment frigate it seeks.
—CDR Rob Brodie, USN
Next Generation Air Dominance Needs a New Flight Path
The authors’ description of procurement-process flaws that led to the F-35 debacle applies to weapon systems of all the services; the DD(X), air tanker, Crusader artillery piece, and Marine Amphibious Combat Vehicle come to mind. Most of the morass, like an iceberg, is unseen. There must be a complete restructuring of the procurement process with strict limitation, if not complete elimination, of the open-ended time-and money-sink that is the quagmire we have today. Radical reform is urgent. Otherwise, decades of developing the finest ship, aircraft, and ground combat vehicle may lead to just one of each. I propose the following rules, or a tweaking of them:
• All projects must produce an operating prototype in five to seven years. Technology advances and requirements occur far too quickly to anticipate availability and needs beyond that time. Projects with a longer timeline are referred to DARPA for further development. New technology can be added to subsequent variants.
• Every proposal is reviewed by a panel of independent scientists, engineers, fleet operators and maintainers, and ordinary civilians. Questions pertain to the need, how the system meets it, and whether there is a less expensive, more rapid way to meet it. Can the system actually be used and maintained in the field, at sea, in the air? Can it be maintained given the amount of money that can be reasonably expected to be budgeted?
• No change orders are permitted after the first metal (or other material) of the prototype is cut, except to meet unanticipated new enemy technology or for proven (by actual users and maintainers) plug-and-play improvements. All change orders before prototype completion require personal approval by the service secretary or Secretary of Defense. After prototype completion and acceptance tests, necessary changes are accumulated and made to subsequent production variants. This rule does not apply to experimental programs.
• Only administrative appeal of any production award is permitted, to a board composed of experts in various types of military systems and cost analysis. A board’s decision may be appealed to the Secretary of Defense, who may affirm, reverse, remand, or decline to review it. Appeals to the court system are not permitted, except in cases of fraud, bribery, or improper official behavior.
—Mitchell R. Miller, Attorney at Law
Bring ASW Back to the Coast Guard
The Challenges of Single-Helicopter Detachments
It was interesting to note in the August Proceedings that a point made by one author might offer a means to meet a need discussed by another author. In “Bring ASW Back to the Coast Guard” (Now Hear This), CDR Corbin notes that a number of excess MH-60R and S models are in storage at Davis-Monthan Air Force Base. These aircraft are there due to changes in the number of littoral combat ship hulls that will be built by the Navy, leading to a surplus.
In “The Challenges of Single-Helicopter Detachments” (Professional Notes), LT Bohlin says single-aircraft detachments suffer from a lack of parts because of the dynamic nature of deployments and the long resupply tail. She recommends two aircraft, so that one can keep flying and improve the ability of the detachment to more satisfactorily meet its mission requirements.
Naturally, two helicopters capable of flight would be most be useful for deployments. However, might it not make sense to take the helicopters that CDR Corbin identifies as sitting in the boneyard, and deploy them with single-helicopter detachments as a spare-parts resource, and to fill other needs of the detachment?
Additionally, the taxpayers might achieve something of a return on the investment in the MH-60R and S models that are now surplus to requirements.
—SCPO Paul H. Sayles, USN (Ret.)
Lieutenant Barnard writes that because potential adversaries may use long-range or standoff weapons, naval control of shipping and sealift vessels may be better served by dispersing embark/debark locations and by hiding ships in plain sight among other vessels in the world’s crowded commercial sea lanes. When operationally required, he adds that some form of convoying and routing will be necessary. But naval control of shipping will always be at the forefront of considering shipping movements, and single vessels hiding in a contested area in wartime is a nonstarter. Ships traveling alone along established routes to Europe were vulnerable in World War I, and in World War II along the eastern U.S. seaboard. The question of when to convoy should have been why we have to convoy. In both world wars, Germany declared a submarine blockade of the British Isles targeted against commercial shipping. In a modern conflict at sea today, neutral or non-involved merchant ships will become rare.
—CAPT Alan B. Coffer, USNR (Ret.)
Captain Pagano laid out an excellent case, but, though there will probably be a place in the future for a pure fighter jet to intercept enemy fighters, the days of the manned strike fighter are almost gone. The speed and accuracy of drones, unmanned aerial vehicles (UAVs), cruise missiles, and soon hypersonic missiles are increasing. Major targets in Syria were hit by cruise missiles, not aircraft; and most high-value targets in Iraq and Afghanistan were hit by drones, not manned aircraft. With advanced drones, manned strike aircraft may soon be out of a job.
Why not embrace the future? For example, a hybrid warship could be designed—a ship that is part missiles cruiser and part carrier. Ironically, the Soviets experimented with such a warship in their Kiev-class carriers. The front end was loaded with guns and missiles, while the rest of the ship was an angle-decked carrier. A modern 80,000-ton warship like that today could carry a large number of cruise missiles and a substantial number of UAVs, as well as manned fighters for fleet air defense. The UAVs could be used as strike/reconnaissance/airborne early warning aircraft, and missiles could be used against both land and sea targets. Manned fighters would be used for defense against enemy fighters and could use V/STOL technology, eliminating the need for catapults and arresting gear. Some helicopters could also be carried for vertical replenishment and search-and-rescue duties.
China is investing in offensive missile technology, so these ships would have to make heavy use of antimissile systems and close-in weapon systems. Defenses would be supplemented by missile defenses on board escorting warships in the task force, which would also be charged with antisubmarine warfare missions. In sum, as we sail well into the 21st century, what we should be debating is what a future carrier should be.
—Remo Salta
Critique of the September Issue
I was perplexed—even a bit disappointed—by the September 2021 issue, billed as naval aviation–focused. I did not find direct discussions of the ocean surveillance and airborne ASW missions of naval aviation, or any photographs of the aircraft and facilities that support these missions. Most of my operational service during the Cold War was devoted to maritime patrol and ASW, with some experience in carrier-based airborne ASW. It seemed that a major segment of naval aviation, in terms of personnel, equipment, and facilities, was devoted to ocean surveillance. It also seemed that maritime patrol provided peacetime information directly related to national security planning. This is the case today, with China emerging and Russia re-emerging as challenges to U.S. sea power. The Naval Institute should recognize the ocean surveillance mission by including the men and women of the maritime patrol force, as well as their equipment and facilities, in this annual focus. I am in contact with many members—active and retired—of the maritime patrol force, so I know they are still out there flying.
—LCDR Cecil A. Harrison, USN (Ret.),
Golden Life Member
Editor’s Note:
The September Naval Aviation issue is not intended to be a wrapup of everything naval aviation does. It is an annual issue featuring mostly articles about naval aviation topics. The annual naval aviation review is part of the May Naval Review issue, and that does include information about every community within naval aviation.