British Submarine Command Course, more commonly known as “Perisher”.

by JOC David Nagle, USN I was an exchange officer attending the British Submarine Command Course, more commonly known as “Perisher”. The British have been running Perisher twice a year since 1917, but until 1994, it dealt exclusively with diesel submarines, and navies throughout the world sent their prospective commanding officers to be tested by the British over six months of tactical training. Until I reported, there had never been a U.S. Navy officer “on course”. With a historical failure rate of 25 percent, everyone wonders on the first day how many classmates will be there at the end – the odds are that with a look to your left and right – and including yourself – you’re seeing at least one officer who won’t make it. If we passed, we would be added to “The Wall” at the British Submarine School in Plymouth, United Kingdom, where the names of all Perisher graduates are inscribed. It would certainly be a tremendous honor and personal achievement for me to be the first graduate with “USN” after his name. I was serving as the Navigation/Operations Officer on USS Memphis (SSN-691) when the detailer called to ask if I wanted to be among those considered for selection to Perisher. Without thinking about it too long, I said yes. During my tour on “The Mighty Memphis,” I deployed to the North Atlantic twice and participated in a host of other interesting operations. It was a challenging and enjoyable tour, and with the reputation of Memphis as strong as it is, I’m sure it played a big part in my selection to the course.

At Sea in Another Navy – and “Foreign” English When I arrived in the United Kingdom in late January, I reported to the British tactical training team headed by Lt CDR Stewart Little. Stewart, a served Executive Officer and Officer-in-Charge at the training facility, was to be my mentor for the eight weeks of indoctrination that prepare participants for Perisher. As I began the program, it was difficult not to feel a little overwhelmed by the prospect of learning not only the differences among platforms, but also of understanding Royal Navy ships and tactics well enough for command at sea. Language differences were the first hurdle. The “Queen’s English” as spoken in the UK can be a challenge. I was frequently asking people to speak more slowly or to repeat themselves. And in ship-driving, they even give rudder orders differently. “Port 15, steer North” was part of my new jargon, and notably, calling an angle on the bow of “Port 30” could well be met with an acknowledgement from the helm that he now had “30 of Port Wheel on.” The first order of business was to study relevant submarine systems from the command perspective – not necessarily the in-depth knowledge I was used to, but it would have to do. I also began to practice periscope-employment techniques in the trainer. A large portion of the course is devoted to learning how to operate a submarine safely at periscope depth amid high contact densities. Rapid, accurate target setups and a disciplined approach to contact management were critical aspects of Perisher on which I would soon be thoroughly examined. During my indoctrination, I was given two underway periods on British fast-attack submarines – HMS Turbulent and HMS Talent, and I was exposed there to a variety of operations on two outstanding boats. Upon returning from sea, I continued to develop my periscope skills while I took on the additional challenge of understanding the British system of preparing charts, employing weapons and fire control systems, and planning inshore operations. These evolutions are conducted in the very shallow littorals and can range from periscope reconnaissance of a port to intelligence gathering on a ship operating in the region. The greatest challenge came from an area that I least expected – navigation and planning. There are no Quartermasters on British submarines. The officers man the navigation plot when the ship is submerged, and all charts are prepared and navigated on by an officer. I found that it was a big step to go from supervising a navigation team underway to actually doing the plotting. My plotting skills were much less than I needed for the demanding situations I would soon find myself in, so I began a crash course in the mechanics of plotting and working the charts. It has been observed that in the U.S. Navy, officers “manage” the navigation and in the Royal Navy, the officers “do” it. Another area in which I observed a basic difference between the two navies is in their approach to engineering. They have Marine Engineering Officers, Weapons Engineering Officers, and Seaman Officers. The Seaman Officers are warfare specialists focused mainly on warfare, navigation, and ship driving. No college degree is required to become a Seaman Officer, but they are masters in the art of submarine warfare. In fact, the other students on course with me had no formal college degrees. Perisher Itself – Classrooms and Trainers On 24 March, the Perisher course itself convened. British Perisher courses have between four and six students, and Perisher 102 had four, including me. From day one, the four of us formed a team that would stay together until we finished our at-sea evaluation. The three other participants were all Royal Navy O-4s. Lt CDR Guy Buckingham served most recently onboard Talent, but our paths had crossed before when Memphis conducted her mid-deployment upkeep in Plymouth, and he was the liaison officer on our host boat, Turbulent. Lt CDR Ed Ahlgren came from HMS Triumph but had also served on diesel boats before the British decommissioned their last one in 1994. Lt CDR Paul Dunn came from HMS Superb in Faslane. All three had experience all over the world in a variety of submarine operations. “Teacher,” as the British PCO Instructor is known, was CDR Paul Abraham. He had been in the Royal Navy for 23 years, with more than 20 of those in submarines, including two command tours. He was an intense warfighter with an unparalleled understanding of submarine operations and an amazing ability to create stress in the Perisher students. The Perisher course is 24 weeks long. The first 16 are focused completely on submarine warfighting, and their culmination is a four-week, at-sea exercise during which the Duty Captains (Perisher students) are evaluated on their ability to employ the submarine across the spectrum of undersea operations. Upon successful completion of the at-sea portion, the students who have passed the course are given their follow-on assignments as Executive Officers and spend a final eight weeks on various administrative courses and visits to military-industrial centers throughout the UK. My exchange program did not include these last eight weeks. We spent the first week of Perisher in the classroom. After an administrative introduction, we started the week with lectures and discussions on leadership and finished with more work on periscope employment. Finally, we were briefed formally on our tactical priorities: First – safety; second – avoiding counter-detection; and third – achieving the mission. All command decisions had to be soundly based on safe principles, and making a decision that resulted in an unsafe condition was the fastest way to fail the course. Weeks 2 through 5 had us in the trainer practicing the periscope skills that would become critical when we went to sea. Teacher evaluated each of us in eight categories every time we got on the periscope: ranging and estimating, mental agility, overall situational awareness, command presence, intellectual honesty, safety, character under pressure, and a unique British evolution known as “Q-drill” for quickly and safely regaining periscope depth when a contact encroaches the “Go-Deep” circle. Perisher’s tradition for handling an unsuccessful student is not to make him aware of his failure until a small boat approaches to remove him from the submarine. Unknown to the unfortunate officer, his sea bag has already been packed by a member of the crew and brought up for the transfer. Upon departure, he is presented with his personal gear and a bottle of whisky, never again to return to submarine service. Week 6 started a series of visits around the UK. The first stop was in Culdrose for a day-long visit with the Merlin Helicopter Squadron. Next, we went to the command center at Northwood, where we had a series of briefs with the British SUBOPAUTHS, and then stopped for a day with the crews of Nimrod maritime patrol aircraft (MPA) in Kinloss. There we met the Dutch participants in Perisher, and we would spend the remainder of that week and the following two weeks with the Dutch. Next was a day at Thales Optronics for a VIP tour and presentations on periscope technology, and we wound up with a fishing-vessel liaison visit to Campbeltown, Scotland, where we went to sea for a day to get some feel for the capabilities and limitations of a working fishing boat. We spent Weeks 7 and 8 in Portsmouth at a multinational Maritime Warfare Course that provided a chance for us to step outside of our submarine-centric world and see where we fit into the overall planning process. The schedule also gave us our evenings free for planning operations and preparing charts for the upcoming tactical phase. Weeks 9 through 12 had us back in the attack center. There, we rotated through the positions of Duty Captain, Executive Officer, Navigator, and Fire Control Officer. Each day, we ran two scenarios and completed 26 over the four weeks. Teacher stressed that the goals of the tactical phase were all concerned with “risk assessment, personal leadership, and the CO’s ability to recognize the time when he must step in.” We started a typical day with a group meeting at 0700 in preparation for presenting our plans for the upcoming operation in the briefing room at 0800. The planning required for each mission was detailed and thorough. All charts used in the trainer and later at sea were prepared by the student Duty Captain conducting the evolution. We also analyzed the threat, determined environmental conditions and their impact on operations, reviewed alterations to the sonar lineup, developed our plan for employing ESM, drafted any messages required, and detailed the tasks that required immediate attention at the start of the problem. The first of our two daily missions ran from 0815 to 1200. At 1200, we debriefed the exercise and grabbed a quick meal, generally bag lunches brought in from the wardroom. At 1300, the briefing commenced for the afternoon scenario, which ran from 1315 to 1700 with debrief immediately following. Then, we would frequently have lectures with Teacher or a guest authority until 1830 or 1900. The four of our team would then get dinner in the wardroom and reconvene from 2000 to 2100 to pre-brief the next day’s runs, review charts, and discuss plans. From 2100 until midnight (or later), we worked individually, preparing for the tasks we had been assigned at sea. This routine continued until 14 June, when the at-sea portion commenced. At-Sea Training in Deep and Shallow Water On that day, we had our gear packed and were ready to go to sea onboard Trafalgar – and then Turbulent – for Perisher’s four-week, at-sea exercise. We would man up the same positions we had covered in the attack center – Duty Captain, XO, Navigator, and Fire Control Officer – in a rotating watchbill. The first three to four days at sea were dedicated to “Eyes Only” or “Safety Training.” During this phase, Teacher had two to three frigates working directly for him. The goal was to give students practice and confidence in working in close proximity to fast, maneuvering ships while seeking to remain at periscope depth. The area chosen for this part of the exercise also featured heavy merchant traffic and moderate fishing and pleasure craft activity. Time on the periscope as Duty Captain was physically exhausting. The torque assist was useless, and we were meeting the scope as soon as it rose above the deckplates. The first run of the day started at 0500, and we continued until nearly 2200 – sunset comes late in England in the summer. Throughout each run, the WT Mast (for communications) was raised to permit Teacher to communicate directly with the surface ships. While we were operating the attack periscope, he observed each run from the search scope, both to evaluate our performance and to ensure absolute safety. Additionally, with two periscopes and a communications mast raised, the surface ships had excellent radar targets for reference as they conducted set-geometry runs around – and sometimes over – the submarine. At the end of the first day, all four of us could barely make it down the ladder from Control. All during the British Perisher course, the Dutch were running their own version – the International Diesel Submarine Command Course. This is convened once per year, taught in English, and offered to the international community. The British and Dutch conduct their Perisher sea training concurrently to enable the two forces to train against each other. Following “Eyes Only,” we began a period of training with the Dutch diesel submarine, HNMLS Walrus. The next phase of the training was our first “Inshore Weekend.” The focus here was on conducting inshore navigation and intelligence training in the presence of potentially hostile warships and neutral shipping. Once again, Teacher arrayed a variety of opposing forces that included frigates, auxiliaries, ship- and land-based helicopters, and MPA. The opposition was given an approximate time and area where we would be conducting operations and the task of finding the submarine. All navigation was done without GPS as we conducted our missions around the Scottish island of Arran. During this period, the students rotated positions after each four-hour segment. This was another particularly exhausting time on the course, and we learned a lot about the effects of fatigue on our decision-making processes. Teacher stressed that sleep is a weapon, and a CO has to recognize when he needs it. Next, we transitioned into deep-water operations. During this phase, we participated in several exercises against air assets, surface ships, and submarines and ran day-to-day operations on the ship. In general, we each served as Duty Captain for a full 24-hour period in deep water. This period also included participation in two Tomahawk Land-Attack Missile (TLAM) exercises and the spring Joint Maritime Warfare Course exercise, a multi-national event coordinated by the British three times each year. The Final Trial – Success or Failure? On 12 July, we commenced our final Inshore Weekend. The goals were similar to those of the first, but now we were tasked to support a notional Amphibious Ready Group (ARG) approaching the coast. Our mission was to report regularly to the ARG with SITREPs detailing intelligence gained from local area surveillance. We were given specific collection goals and intelligence detailing enemy strengths and expected weapons locations. The requirement to report in regularly while an alerted enemy was actively searching for us further complicated managing our counter-detection risk. In the back of our minds during this final weekend was the fact that we could still be removed from the course for unsatisfactory performance at any time until the ship surfaced on the afternoon of 14 July. Perisher’s tradition for handling an unsuccessful student is not to make him aware of his failure until a small boat approaches to remove him from the submarine. Unknown to the unfortunate officer, his sea bag has already been packed by a member of the crew and brought up for the transfer. Upon departure, he is presented with his personal gear and a bottle of whisky, never again to return to submarine service. It is not unheard of for a student to be removed from the course immediately before the last intelligence-gathering mission – but in our case, all four of us passed. Two of my “mates” are now serving as XOs on Plymouth-based Trafalgar-class SSNs, and one is at Faslane on a Vengeance-class SSBN. Looking Back – Lessons Learned So, how does Perisher benefit the U.S. Navy? Certainly it fosters closer collaboration between the submarine forces of the United States and the United Kingdom. I was immersed in British submarine operations for six months in what is one of the premier training programs for submariners in the world. As we worked on navigation, tactics, weapon employment, ship-driving, shallow-water navigation and intelligence-collection, it was an opportunity to experience operations with another navy and explore alternatives for accomplishing a mission. The Perisher exchange will continue in the future with two U.S. officers attending each year. I was selected as a served Navigator, but the program is open to any post-department head nearing the end of his shore-duty tour. For planning purposes, one U.S. student will report to the UK each January and July for six months of instruction. In return, the British will be sending a student to attend our PCO classes starting in 2003. Being the first American at Perisher drew a lot of interest from the officers and enlisted men I encountered. When asked frequently why I wanted to undergo such a rigorous and stressful trial, I could only answer, “How could I pass it up?” From the British point of view, Teacher observed that there was somewhat more competitiveness in our class than he had seen previously. I found myself working extremely hard to match the performance of my colleagues, and they in turn would respond by raising their standards, each of us feeding off the motivation demonstrated by others in the group. There was no real competition to be the best in the class, but rather the shared goal of seeing all of us pass, which drove each to work as hard as necessary to see his shipmates succeed. Overall, my time with the British on Perisher was unforgettable, and the guys who were on course with me – living in the Plymouth Wardroom, working out, eating, and drinking together – will be friends for life. Being the first American at Perisher drew a lot of interest from the officers and enlisted men I encountered. When asked frequently why I wanted to undergo such a rigorous and stressful trial, I could only answer, “How could I pass it up?” Aside from deploying on Memphis, it was the most challenging and demanding time I’ve had in the Navy, and I would definitely do it again. The British are outstanding hosts, shipmates, friends, and allies, and I’d certainly recommend Perisher to all my fellow submariners. Prior to Perisher, LCDR Mack had served on USS Alaska (SSBN-732)(Gold) and USS Memphis (SSN-691) and ashore at the Johns Hopkins University Applied Physics Laboratory. He is currently the Director of the Officer Navigation Training Division at the Navy Submarine School in Groton.