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Contents:
Polar Star—Sitrep One 103
By ^ear Admiral Norman C. Venzke, U.S. Coast Guard Polar Star—The Second Time Around 107 BV Captain R. G. Moore, U.S. Coast Guard
The Polar Sea's Story 112 By Mark Clevenger
U.S. Coast Guard Icebreaker Support Facility 115
By Commander D. G. Langrock, U.S. Coast Guard
-'■'uing
Iarly ft, ^oubt i
The USCGC Polar Star (WAGB-10) ^as placed in commission as a Coast j Uar<l cutter on 17 January 1976. As n°ted in a January 1976 Proceedings Professional note, “the U. S. Coast k Uar<^ acquired a vastly increased icebaking capability with the construc- tlon of the Polar Star. ” Now, after rtlore than two years of operations and Problems, it is an appropriate time to ^ke a situation report on the prog- bss of the Polar Star and her sister j lp> the USCGC Polar Sea (WAGB-ll). ^ this report, I will describe the Polar f*r s Post commissioning/pre-ice test, e Arctic ice test, and the post-ice J'jst/propeller refit periods. (Editors
TE: The Polar Star’s current comending officer, Captain Robert G. tr°ore’ W*U describe her second ice test, ace her progress through another major r« period, and forecast what he expects
M ship as he prepares her for a mid- Wember Antarctic deployment. Mark evenger will review the Polar Sea’s Finally, Commander Langrock s‘ l Scribe how the U.S. Coast Guard Pport Facility will help ease the Polars’ Workload.)
fie Polar Star's post-commis- pre-ice test period was particu- istrating and troublesome. No t was typical of the first days of any leader of a class of sophisticated ships. At times, it almost seemed as if the Polar Star was not destined to carry out a shakedown. During the shakedown in Puget Sound and the Strait of Juan de Fuca, serious problems required her to return to port three times and further delayed her Arctic ice test. The problems included a major failure of her steering system, the inability of the bilge and fuel transfer system to take suction on the bottom tanks, and main propulsion control system malfunctions, as well as other types of problems one would expect to encounter with any new piece of machinery. And, to add insult to injury, she suffered a grounding which was not related to equipment problems. Fortunately, the grounding caused no damage. Despite these formidable problems, between the efforts of her hard working and competent crew and Lockheed Shipbuilding and Construction Company, the Polar Star completed a successful local shakedown.
The ice test period commenced when the Polar Star departed Seattle on 24 May 1976 for the Arctic. She was performing well. Her crew was eagerly looking forward to working in the ice. And the normally rough Gulf of Alaska afforded an unusually smooth transit to Unimak Pass in the
Aleutians. The Polar Star’s luck seemed to be improving. During the transit of the Bering Sea, very little ice was encountered until our 3 June arrival off Nome, where the ship encountered four feet of fast ice (attached to the beach) with a concentration of eight octas (eight-eighths of the surface covered). Although the ice was beginning to deteriorate, it produced considerable resistance and made for some interesting icebreaking. During that period, I used the ship’s diesel-electric plant which provides a maximum of 18,000 shaft horsepower (s.h.p.). Although backing and ramming were necessary, it was apparent that her 13,000-ton displacement was a marked improvement in U. S. Coast Guard icebreaking. I evaluated her performance as good.
Soon thereafter, we proceeded north of the Bering Straits to locate ice more suitable for test purposes. Again we discovered ice rapidly deteriorating due to the high air temperature. Consequently, I elected to proceed to the vicinity of Point Barrow where the probability of locating suitable ice was higher. As the ship moved northerly through the Chuckchi Sea, approximately 75 miles north of Little Diomede Island, she encountered heavier and harder ice. The ice ranged from three to six feet in thickness with
crisscrossing pressure ridges ranging up to 16 feet in thickness. At the time, I was employing the diesel- electric plant. Progress was slowed considerably to the point where I had to back and ram frequently, perhaps maintaining a speed of advance of 2 knots.
At this point, I changed my main propulsion combination in order to increase available power and thus achieve a higher speed of advance. I placed a gas turbine on the center shaft (20,000 s.h.p.) and retained two diesels on each wing shaft (12,000 s.h.p. total). By using 20-25,000 s.h.p. (full power was not required), the Polar Star achieved a speed of advance ranging from 3 to 7 knots, making easy progress through the lighter floes and broken ice and more difficult progress in heavier areas. Although ice was continuously ingested into the propellers, the severity did not seem any greater than during periods of transit through much lighter ice. The need for backing and ramming was virtually eliminated. Progress was outstanding.
Then, on 7 June, after penetrating to a point of 15 miles from the edge of the heavy ice, the starboard shaft lost revolutions per minute (rpm), dropping from 130 to about 60. That, in itself, could be expected temporarily of an overloaded shaft. Supporting this possible explanation, a heavy floe tilted on edge was located near the starboard propeller. However, shortly thereafter, the ship picked up a vibration with a frequency of about one cycle per second. That meant trouble. Divers checked for external damage to the shaft and propellers but found none. At that time, I erroneously evaluated the problem to be a stern tube bearing failure. In any event, the ice test had to be aborted. The casualty was reported to the Coast Guard operational commander, Commander, Pacific Area, and plans were made to extract the ship. The next morning with the starboard shaft locked, I slowly altered course 180° to the right to course 180° T and proceeded toward the ice edge. During the night, the drift of the ice resulting from the southerly wind had caused the Polar Star to drift about seven miles to the north northwest. However, her position relative to the ice edge had remained the same.
I employed a gas turbine on the center and port shafts thereby making available 40,000 s.h.p., albeit in an asymmetric configuration. Progress to the ice edge was slow, taking about eight hours or twice the time it took for penetration. The relatively l°w speed of advance minimized damaging the locked starboard propeller. Additionally, despite the large centerline propeller and rudder, turns to the left in heavy ice were difficult as a result of the asymmetric power available, ft seemed that whenever an alteration to the left was necessary, a deep pressure ridge appeared as an obstacle on the port bow. By late afternoon on 8 June, the Polar Star cleared the heavy ice and proceeded south toward the Bering Straits. Thereafter, the ship encountered ice ranging from two to seven octas. Progress was good on the morning of 8 June; we were transiting ice of seven octas concentration about 20 miles south of Little Diomede Island. Two diesel engines were being used on the center and port shafts. At that time, the port shaft developed the same symptoms as the starboard ha two days before. Again, the divers could not detect any external damage- I concluded that a similar failure ha occurred. My concern at this point was heightened in view of the failure of two out of three shafts. What was the status of the center shaft? Consequently, when I made my report to
ornrnander, Pacific Area, I requested at an escort vessel be provided for °Ur return to Seattle, p ^trh the port shaft locked and all lrigers crossed, the Polar Star competed her transit of the remaining Ur miles of ice using a gas turbine p11 che center shaft. Thereafter, the °ar Star proceeded to an anchorage ^ miles northeast of Gambell, St. avvtence Island, where we awaited arrival of an escort vessel.
°n 13 June, the Polar Star rendezvoused with the USCGC Citrus (WLB- °°)> an ice-reinforced 180-foot buoy of^der, a^our 400 miles to the south , Lawrence Island. The transit of e Bering Sea to Unimak Pass was °mpletej on June when the JCGC Mellon (WHEC-717), a 378-foot a%/7to«-class cutter, relieved the Cit- at Unimak Pass. Due to the high fa8 of the locked port and starboard Propellers, the return to Seattle was w> with a maximum of 9.5 knots Ossible when the weather was calm.
he post ice test period commenced P°n the Polar Star’s return to Seattle 24 June 1976, The first order of Us*ness was to determine what had Used the failures. Contrary to my ^ar ier belief, the stern tube bearings a not failed. Instead, the pitch
changing mechanisms in the hubs of the port and starboard propellers were literally destroyed. By way of description, a hydraulic piston is installed longitudinally in each hub with linkage arms connecting the piston crosshead with each propeller blade. Thus, movement of the piston causes the propeller blades to rbtate and change pitch. Three linkage arms were severely bent and one broken in the port and starboard hubs. The associated bearings were in pieces. The center propeller had not been as severely damaged.
What caused such destruction? The specified material had not been used in fabrication of the linkage arms as verified by material analysis. Further, it was decided that simple upgrading of the material was not the complete answer. A major redesign was initiated for the purpose of making the pitch changing mechanism as strong as possible and consistent with size restrictions of the hub. The Polar Star commenced a long availability period lying alongside the pier at Coast Guard Support Center, Seattle, with no propellers. The remaining warranty items plus necessary modifications were completed while waiting for the propellers.
Now, it is time for some good news. I am convinced that the Polar Star and the Polar Sea will be great icebreakers as soon as their propeller problems are resolved. I base my belief on my experience with three Wind- class icebreakers and my brief opportunity to observe the Polar Star in ice. She has the necessary attributes: power, weight, and a good hull.
The Polar Star has a horsepower-to- displacement ratio of 4.61 compared to 1.53 in the Wind class. That is why she was able to maintain a speed of advance of up to 7 knots in the ice described earlier. The Wind class simply could not achieve such performance. After the first propeller casualty, the Polar Star frequently pushed through pressure ridges of up to 16 feet without stopping while using two-thirds of her designed power. Under full power, she is in another league entirely. Perhaps she is overpowered except for the very heaviest ice. In that regard, I believe that to prevent damage, care must be exercised in using all three turbines for ramming. Also, I believe that it is possible to push the Polar Star through heavy ice at an excessive speed and perhaps damage the propellers and hull. For that reason and sub-
sequent to the test, she has been equipped with doppler speed devices to ensure that she is not inadvertently accelerated to excessive speeds. That installation is particularly important since the "seaman’s eye” approach to speed control is hampered by the enclosed bridge being 51 feet above the waterline and the aloft conn being 102 feet above the waterline.
Her 13,000-ton displacement provides the weight necessary to break thick ice. And her powerful main propulsion forces her onto it with relative ease in a ram. By comparison, the old, hardworking Wind class has a 6,515 ton-full load displacement which significantly limits its capability.
The designer certainly provided the Polar Star with a strong, superior hull form. No hull damage was incurred during the test. I was most impressed with the way she extracted after being stopped during a ram. In most cases, she remained trimmed by the stern and slid off easily when about 50% backing power was applied. Thus, the heeling system was required infrequently. The shape of her afterbody is particularly noteworthy. In ice concentrations up to and including six oc- tas, the ship did not experience severe ice ingestion provided she was kept on a relatively constant heading. The shape of the afterbody permitted the ice to rise and rotate clear of the propellers. Of course, a final evaluation of her hull form must await the analysis of the data obtained during the ice tests in Antarctica.
I was concerned about the severe ice ingestion into the propellers which occurred in concentrations of seven to eight octas. It may be determined that in concentrations of seven to eight octas, an excessive amount of ice is forced back into the propellers because of her hull form. The reader should remember that the Polar Star is equipped with controllable pitch propellers and that nothing can be done to reduce rpm prior to impact with the ice. Obviously, great stress and pressure are placed on the blades as they chop through ingested ice. The only course of action available to the conning officer is to judiciously reduce power and thus reduce the speed of the ship through the ice. This, of course, in turn reduces some of the stress on the propellers. For the record, the screws were designed to take the stress of chopping in congested ice, and, in fact, the propeller blades, shaft, and bearings did withstand the stress. Other than a few minor dents and knicks in the blades, all external components were in good order upon the ship’s return to Seattle. Of course, that was not the case with the pitch changing mechanism located in the propeller hubs.
One potentially dangerous situation involving propellers and ice ingestion was determined as a result of the test—that of blades having a negative angle of attack. For example, if the ship has sternway and pitch is reduced or shifted to ahead, it is possible for ingesting ice to strike the trailing edge of a blade. If that occurs, it IS likely that the thin trailing edge will incur damage.
Finally, for those unfamiliar with icebreakers, the Coast Guard was m the vanguard of propeller technology when it employed the first controlla* ble pitch propeller in polar ice. Al' though Captain Moore has much more to say on this subject and further tests will better define the Polar Star s capabilities, I am confident that we will solve the problems and that the Polar icebreakers will fulfill our expectations. ("Author’s Note: I don’t believe the “vibrationless ride”can be achieved by high-powered icebreakers. One other court- try has experienced similar vibration difficulties with its high-powered breakers.)
.^ear Admiral Norman C. Venzke Sa'd of the Polar Star's post-commis- s*oning period that, at times, it al- ^0st seemed as if the ship was not ^seined to carry out her shakedown. ^e Was> of course, speaking of that ustrating period when he—as the 0 ar Star’s first commanding office.' Was busy getting her from the [QUl. r s hands and into service. I, following Jater> t00k ,-hg shjp
in June
^ ’ and shared similar remem-
rances of the preparations for and Pareicipation in the ship’s second ice Tlals and first Antarctic deployment.
0 me it often seemed not just that . urphy had reported aboard, bring- ^**s Law with him, but that he was s° running the operation!
Shortly after her first trials in late ne 1976, the ship's three propellers re removed and shipped to the sls'Chalmers plant in York, Penn- Vania, for a rework which, simplis- tically, consisted of beefing up the internal components to the maximum strength possible within the physical limits of the hubs. (Allis-Chalmers was the original manufacturer of the propellers, acting under license from the designer, the West German firm of Escher-Wyess.) The resultant increase in strength was considerable. (See Table 1 for a comparison of before and after values.)
We in the ship followed the rework closely, and then tracked each propeller as it moved cross country by rail. Each morning we obtained a position report from the railroad and religiously posted it to a chart of the United States. The chart itself we displayed outside the mess decks so that everyone could watch the progress. There were slippages in both the rework and shipping schedules, and it was not until 7 September 1977 that we moved to Todd Pacific’s Seattle yard for the reinstallation itself. Again we experienced slippages, resulting from the problems of reassembly and reactivation of complex hydraulic systems which had been either idle or undergoing work for over a year.
The reinstallation work was finally completed late in the evening of 7 November. By that time we were so pressed that the post-yard sea trials were conducted between 2300 that night and 0800 the next morning,
Table 1: Strength Specifications of the
Polar Propellers
Component | Original | Modified |
Drive Pin | 3.8x10“ Lb-In | 15.6 x 10* Lb-In |
Crank | 507,000 Lb | 2,220,000 Lb |
Link Pins | 314,000 Lb | 850,000 Lb |
Link Bearings | 396,000 Lb | 882,000 Lb |
Link | 178,000 Lb | 852,000 Lb |
NOTE: All loads except Drive Pin based on fatigue life of 107 cycles.
when we went alongside at Manchester, Washington, to refuel. At 1000, 15 November we departed Seattle en route to Antarctica via Wellington, New Zealand. I will not dwell upon the period beyond saying that, between logistics, training, and trials, we had our hands full. If it hadn’t been for the quality and dedication of the ship’s company we simply wouldn’t have made it.
Since the second ice trials were combined with an Antarctic deployment as part of Deep Freeze 78, some background information about the operation is in order. Deep Freeze is the nickname accorded the U. S. Navy’s operation which provides logistics support for the U. S. Antarctic Research Program. The program itself is conducted under the auspices of the National Science Foundation. The Coast Guard icebreakers which participate do so under the operational control of the Commander, Naval Support Force, Antarctica.
In general, the icebreakers have two main tasks. Although an increasing percentage of people and material moving to and from Antarctica are transported by air, heavy equipment, bulky stores, and fuel are carried in Military Sealift Command (MSC) ships.
The Antarctic terminus is McMurdo Station, the principal U. S. base on the White Continent. The approaches to the station are guarded by the shore-fast ice of McMurdo Sound and so the first task for the icebreakers each year is to open a channel through that ice so that the MSC ships can berth at McMurdo Station. Once cut, the channel must be "tended” to ensure that it remains usable until the last ship has departed. The second of the main tasks is to provide direct support to those National Science Foundation research projects which require mobile platforms. In this phase, groups of scientists are embarked in and use the facilities of the ships to carry out their work. The Polar-class icebreakers have accommodations for up to 18 scientists and technicians, and there are five offices and laboratories for their use. The ships are also equipped with oceanographic winches, a computer with which to process oceanographic data, and other facilities with which to support research. In addition to the two main tasks described, collateral assignments for the icebreakers may include search and rescue and similar contingency operations.
The specific objectives of our Deep
Freeze 78 deployment were ^ To test the modified propellers and the ship herself in ice and under controlled conditions
► To break the channel into Me- Murdo Station
► To participate in the development of operating and engineering parameters which would permit safe, reliable employment of Polar-class ships
y To conduct scientific support operations
The testing program was an elaborate one, involving two broad areas or interest. In the first area, we were seeking data which would verify °r become the basis for changes to the theoretical model employed in the m1' tial propeller design. (The same data would determine the adequacy of the propeller “fix” itself.) Second, we wanted to measure ship and machinery responses, including ship motion an hull loads during icebreaking, as <n' puts to future icebreaker design. The team put together to accomplish this was drawn from both the Coast Guar and the Navy. The Navy’s interest stemmed, of course, from the increasing application of controllable pitch propellers to warship design and construction, and their representatives
came from the David Taylor Ship
a^ch and Development Center, th • C *nstrumentat'on assembled for tvv teStS WaS 'mPress've- F°r example; rj ° t^le ship’s three propellers were dev^ W'C^ stram rosettes and similar vVf *CeS su^r‘clent in number to pro- -p^e ^ channels of data per propeller. Scre. ‘formation thus obtained de- pe1 C<^ rather precisely what was hap- t0 t^*e ProPe^ers both in open er and during encounters with ice. ae ^ata were carried by telemetry to CQ *jntral point where they were re- strue<^ f°r later analysis. The in- v*d ?entat*on arrangement also pro- ^ e. 1‘mited capability for real -time Thin7r'n« °f selected critical points, to S eature proved extremely valuable sincee wl‘ile we were operating in ice, and 6 'C a'^e<^ *n rhe selection of speeds "'i L .rnaneuvers which kept stresses ln predetermined limits.
l'mitSSa^e t0 ^,eb‘n8ton and to the r0uS rbe ice was not precisely ‘dlen^ ^ter 15 months of dockside testj ess’ rraining and engineering dersn«and calibration became the or- tfansit C^e during the outward high d ^°*ar c^ass incorporates a c°nte&ree °f automation and remote nee ° ’ su^*cient so that the engi- neerj'n^ spaces—except for engi- ng control center and roving security watches—are unmanned under normal circumstances. Assuring the proper functioning of the gadgetry which makes this possible represents quite an effort.
I must say that it was a joy to finally get to sea. I was also pleased to find the ship a delightful change from the Wind-class icebreakers. The Winds wallow and roll in a most ungainly and uncomfortable fashion, but the Polar Star rides very nicely. About twice the size of the Winds, the Polars have finer lines and a harder turn of bilge and, as a result are much more sea kindly. In addition, part of the improvement in sea-keeping stems from markedly better directional stability. The location of a great barn door of a rudder right aft of the centerline propeller enables the ship to steer fine and to retain rudder control until almost dead in the water, providing only that ahead pitch is kept on the centerline screw.
After sighting our first ice on 21 December, we entered the outer pack on the 22nd. The testing program called for proceeding methodically from the very light ice of the outer pack through progressively more severe conditions to the fast ice in McMurdo Sound. This approach was logical from the testing standpoint and also gave us a few days to get a feel for the ship’s behavior in ice before starting the break-in.
Although the break-in was included within the testing, it was also the first part of the operational assignment. As such, we had a timetable to meet. To avoid delays and the attendant risks, the McMurdo channel has to be ready each year to accept traffic by the time the first MSC ship arrives. Historically, the break-in has required the combined efforts of two icebreakers for about seven days. This time, although USCGC Glacier (WAGB-4) and USCGC Burton Island (WAGB-283) were waiting in the wings to either assist or to take over if needed, the Polar Star was to do the ice breaking by herself.
We were faced with about 15 miles of shore-fast ice ranging in thickness from 2.2 to 2.5 meters. The one bothersome circumstance was the presence of an unusually heavy snow cover, 20 to 75 centimeters deep. We started through the shore-fast ice about mid-day on 30 December and arrived alongside the wharf at McMurdo Station at 0635, 1 January 1978. Excluding the periods of frequent stops connected with the testing program, the inward run totalled 31
4,lf i*8;s*s
■Mm':!
U.S. COAST GUARD
hours and 57 minutes.
The job was far from finished. The channel remained to be widened and the ice within it reduced. A turning basin and the approaches to the wharf had to be broken out. Judging by our performance coming in it looked as if the job could have been wrapped up with another 48 hours’ work. We’d done the run in on gas turbines, the ship had performed magnificently, and all of the propeller data fell within stress values calculated as safe. Planning went forward to bring the testing to conclusion and to get on about the business of a routine Antarctic deployment. We spent two days alongside the wharf checking things, and the more we checked the more we were convinced that everything was 4.0.
I couldn’t help but reflect upon the difference between what we’d just accomplished and my earlier experiences in the Burton Island. The increase in capability from the Winds to the Polar class is phenomenal. On diesels alone the Polar Star performed well, better than the Winds, given her displacement and horsepower. Switching from diesels to turbines was like moving from a heavy truck to a sports car. When we shifted from diesels to turbines for the first time I picked a spot where we had been stopped by the ice at the end of a ram. Had we remained on diesels, the technique would have been to back away about a ship s length, charge forward until stopped by the ice, repeating the cycle over and over again to make progress along the intended track. As it was, when the turbines were engaged I moved the pitch control levers slowly forward. At the point when 60% ahead pitch had been applied, the ship began to move and then to pick up speed. Pitch had to be sharply reduced to level off the acceleration!
Of course, the ice in which this occurred was somewhat thinner than the two-plus meter shore-fast ice encountered during the break-in. That thickness, by the way, is very close to one of the design parameters of the Polar class, “. . .to break six feet of homogeneous first year ice at a continuous speed of advance of three knots.” We had to back and ram the whole way in, even on turbines, but there was that “feel” that just a little more power—or a little less ice and the ship would have kept moving. We might have, too, if it had not been for the snow cover. Snow soaks up power like a sponge, and the friction between it and the flatter portions of the
forward hull acted like a huge brake.
On turbines, other things changed besides acceleration rates and icebreaking capabilities. Milling of ice by the propellers occurred more frequently and the loading seen by them was significantly higher. The hull form functioned nearly perfectly in keeping broken ice out of the screws, but “nearly” meant that about 10% waS sucked through the propellers. When such contacts occurred, the resulting vibrations were strong but not remarkably more so than those of the Winds under similar conditions.
Against this background of success and confidence we sallied forth to complete the break-in. We started by rerunning the path made when coming in, both to counter the refreezing which had taken place and to add to our data base. It was immediately evident that we had troubles.
The number of encounters between the propellers and the ice increase dramatically, until milling was occurring at least 75% of the time. R®' corded stresses increased also. Sti within the calculated safe limits, they were much nearer the high end than heretofore. And the vibrations were something else! I reported them a* "awesome” then and even now, wit
thin
W
pla u longitudinal dis
fhgements approached one-half inch. syst C°nt‘nuous shaking affected other faj,erns also. Electrical and electronic
ores
developed, traceable to c0n ' wires, popped relays, and en„nect0« which vibrated loose. The control console failed.
vy loads, but it did make 'gs more tolerable.
w,, continued on with the job. We n rerun had been completed egan to widen the channel by cut- frog another line about 200 feet over m the original track. During this
Pel^' Ca^ec^ scaffing, the wing pro- tr °n t^le s’^e toward the original ar>d hm*bed ice almost continuously ^t e vibrations remained intense. esP*te measurements indicating 5^ ^ Ptopdlers were staying within thr lfn'tS’ * was concerned. Complete in USt reversa^s were taking place dur- 4 C^0se Periods when the propellers Coi[e in contact with ice. The thrust aste3^ ^°unte<^ between the ahead and l0aeJn sboes because of the alternating . ‘ng, anrl longitudinal dis-
tapped
eljmneer’n8 '•"uuui cunsoie ranea, un *nat‘n8 our ability to steam with anned enginerooms. e starboard controllable pitch
propeller hydraulic system developed signs of contamination in the form of a dark gray mud, and increased pressures were required to make pitch changes. In a very short space of time indications of similar contamination were detected in the remaining two pitch systems. The pressure required to make pitch changes continued to increase and the rate at which the blades slewed during pitch changes slowed. The time had come to pack it in. We turned over our remaining tasks to the Glacier and the Burton Island and headed north.
We returned to Seattle on 8 February 1978 and dry-docked the Polar Star soon thereafter. The three propellers, showing no visible signs of damage or deformation, were removed for rework. It was only after the first one had been disassembled that the problems became clearly visible. There were no catastrophic failures of the magnitude of the first time around. A full technical explanation would be overwhelming and out of place here. But in plain terms, and without regard to the sequence of failure, the rollers which lie at the root of each blade in a plane normal to the blade axis had moved out to make contact with and machine the bronze bushing
within which the blade rotates. The rollers cut a groove in the bronze, and the resulting powder was one of the sources contaminating the oil. The bushings themselves, perhaps as the result of the torque of the machining just described, had rotated against the stakes holding them in place. There was fretting, the blade seals were damaged, and there were other problems. I believe that the propellers may well have failed because of the number of pitch changes, even if ice had not been encountered.
It seems that the vibration problem will, in the long run, prove the most challenging one. It appears that the thrust bearing foundations are not stiff enough for the conditions encountered. As a consequence, the thrust bearings are rocking in response to the changes in thrust produced when in the ice and when the propellers are milling ice. Currently, the foundations of the two wing shafts are being stiffened by adding steel.
Scheduled repairs and modifications should be completed on 15 October, and we are scheduled to depart for Deep Freeze 79 in mid-November. The questions that remain to be answered are "Have the problems been solved, and will the ship be ready for
unrestricted operations this winter?” Obviously what is being done is less than the ultimate, due to time and dollar constraints. I believe that there is a high probability of successfully completing the next deployment, but that good judgment will be required to avoid exceeding reasonable limits. Testing during the next deployment will probably be limited in scope, with a more definitive program re
served for summer 1979 or later. One of the major reasons for holding off is that we are at an awkward position on the learning curve. Last winter we obtained a tremendous amount of data, some of which was not available before from any source. The evaluation of that data will take until mid-1979 and, even then, I should think that some additional time would be required to apply the lessons learned.
We must wait for that additional information before moving much farther ahead.
After seeing the Polar Star perform, I am convinced that she and her sister are and will continue to be valuable national assets. The Polars introduce into the U. S. icebreaker inventory a new dimension of capability at a time when there is increasing interest m doing things in the polar regions.
The Polar Sea's Story
By Mark Clevenger, Instructor in the School of Business at the University of Washington and free-lance writer
The USCGC Polar Sea (WAGB-ll), commissioned 25 months after the Polar Star, will follow her sister ship into Todd Shipyards Corporation’s main Seattle dry dock this month. The second Polar-class icebreaker will undergo the repair of her propeller systems and a beefing up of the thrust bearing foundations, work also accomplished on the Polar Star, among other items.
Operating under restrictions based on the Polar Star's operational experiences, the Polar Sea has had a less eventful life than the lead ship. The Polar Sea has nonetheless benefited from lessons learned during the Polar Star’s construction and operations.
The Polar Sea should face her first full tests in the ice when she heads into the Arctic under her new skipper, Captain Herbert H. Kothe. According
to present plans, the Polar Sea head north in 1979 to penetrate farther into the Arctic Sea and face tougher ice than the ship encountere on her first trip to the Bering Sea.
Limited to using only her diesel- electric plant in the ice because of the Polar Star's propeller and vibratio11 problems in the Antarctic, the Polttf Sea ran her gas turbines for only 2 hours in open water on her return trip
^est 1978 (aww 78).
Constructed under the same con- ract as the Polar Star, the Polar Sea’s eel was laid 21 November 1973. The ‘P launched into the West
shi
lilLU LUC WCSl
aterway of the Duwamish River r°m Lockheed’s Harbor Island ship- Xard on 24 June 1975. Completing c°mbined builder’s and acceptance fIals on 7 January 1977, the Polar Sea ^as delivered to the Coast Guard on January 1977.
"The Polar Sea began “fast” tests, ^'mulating full at-sea operations while e to the ship’s home pier at the oast Guard Support Center just off £ askan Way, south of the Port of eattle s central waterfront. On 31 January 1977, the ship’s company and e then commandant of the Thir- ^eenth Coast Guard District headquar- ^re<J in Seattle, Rear Admiral Chester ' Richmond, participated in brief erernonies commissioning the ship, ‘n special.”* The next day, the ship J-d out through Admiralty Strait tr. days of shakedown and crew aining. On 17 February, the Polar
%*.jn ,
^ (''omniissn)n Special" means a cutter is not
y for unrestricted operations but is in the final stages nf „ .
stat PrePatations prior to going on action
Sea transited the Strait of Juan de Fuca to breast Pacific waves for the first time and headed south for San Francisco. The ship, using her gas turbine power, averaged 22 knots on the run to San Francisco. On 26 February, the ship returned to Seattle. A week later, the ship went into the Lockheed yards for dry-docking and removal of propellers for shipment back to York, Pennsylvania, and rebuilding at Allis- Chalmers’ Hydro Turbine Division.
Commenting on the long wait before the Polar Sea entered the Todd yard for reinstallation of the propellers, Commander John T. Howell, then the executive officer who became interim commanding officer when Captain Richard P. Cueroni was named chief of operations for the Thirteenth Coast Guard District, reported that crew morale was a problem.
All of the crewmen had been handpicked for the new icebreakers and what was to be a rather glamorous set of pioneering trips proving out the ships’ advanced hull and icebreaking systems. Instead, as Commander Howell pointed out, the crew faced long months of poor newspaper headlines, shore-based routine, and gibes about living in “Buildings 10 and 11.”
But things began to move faster for the crew when the ship began her major shipyard availability in mid- November, coming out of the Todd yard on 23 January 1978 with propeller systems reinstalled. The ship moved immediately to Manchester for fueling. At a 24 January cruise planning conference representatives of the Coast Guard commandant, District Thirteen, Alaska’s District Seventeen, the ship s company, and a four-man science team that would accompany the ship, laid down the operational dimensions of the Polar Sea's first Arctic venture.
The ship’s shakedown began 1 February, a year to the day from her first cruise, with people from the Fleet Training Group, Pearl Harbor, on board to help train engineering and damage control crewmen. The ship returned to Seattle 11 February, and the next day shims were installed in all the main and service diesels’ engine mounts. The shims would limit engine movement to prevent exhaust expansion joint failure as had occurred on the Polar Star’s transit to New Zealand.
Finally, on 23 February 1978, the Polar Sea was officially commissioned for active duty at the Support Center.
Meanwhile, Aviation Detachment 69 had been formed at the Coast Guard Aviation Training Center,
mal
ship suffered her most serious
Mobile, Alabama, and assigned to the Polar Sea. Detachment 69—four pilots, ten rated enlisted men, and HH-52A helicopters 1402 and 1415— arrived in Seattle three days after commissioning.
On 1 March, the Polar Sea departed the Support Center. Shortly after the ship cleared Pier 36, the Detachment 69 helicopters flew on board. Then the ship passed through the Strait of Juan de Fuca and headed north on the Outside Passage to southeastern Alaska.
The ship carried 15 officers, 125 of the ship’s assigned crew of 127, the 14-man aviation detachment, medical and dental technicians, and the four scientists. In addition to other provisions, 45 movies, 900 library books, games, cards, gym and weight-lifting equipment (which were in almost constant use), stereo music tapes, and video equipment provided a wide range of shipboard entertainment. The crew could watch pre-taped TV shows and such ship-produced shows as scientists explaining their missions and aerial views of the ship breaking ice.
In fact, with the vastly improved living quarters aboard, the official cruise narrative reported that crewmen had to be “lured” out of their spaces for the usual "blowing off steam” group events.
On 3 March, the ship rounded Cape Decision and stood into Chatham Strait, en route to Juneau via Frederick Sound, Stephens Passage, and Gas- tineau Channel. The ship moored on 4 March at the Juneau City piers in a gusty 30-knot wind with the help of two tugs. Two days later the ship departed, going through Stephens Passage, Lynn Canal, Icy Straits, and Cross Sound to the Gulf of Alaska. On 9 March, the ship passed through Unimak Pass, the usual gateway between Unimak and Unalaska Islands to the Bering Sea. The ship encountered "gray” or new ice about 30 miles south of St. Mathews Island on 10 March and both helicopters launched to reconnoiter the ice to Hall Island. The following day the ship anchored off the southwest cape of St. Matthews to let the science team continue its mission.
Measurements of the sea conductivity and temperature versus depth had begun with the edge of the ice pack in sight, using the ship’s oceanographic boom for casts through the ice marginal zone.
During the trip, scientists and assisting technicians launched 62 expendable bathythermographs (XBTs), made 372 weather observations, 14 of which were transmitted to Washington, D.C.; made 122 ice observa tions transmitted to Suitland, Mary' land; and took 152 salinity samples—either by bucket or ffolT1 the pressure gauge of the ship’s sanitary system pumps in the turbine room when the weather decks were se cured.
On 14 March, the helicopters the four scientists and about oo pounds of gear to Hall Island, recover ing the party in the afternoon. The aircraft flew five sorties the next day> surveying the ice en route to St. La" rence Island and dropping signa underwater sound charges in supP°ft of the science mission.
While on the way to the island, c e function of the deployment. A trans former in the diode failure counting circuit of the 3B rectifier burned out. putting a main generator out of c0^ mission and reducing power avail® to the port propeller shaft to a sing engine for the rest of the trip.
The ship anchored off St. Lawrence on 17 March. Over the next few days’ icebreaker LCVPs and the helicoptef transported scientists and gear ba
COAST OUAPO
U.S. COAST GUARD
Each ship carries an aviation detachment of two HH-52A helicopters for performing ice reconnaissance. Like the ships themselves, the aircraft are painted red to enhance their visibility in the ice. Plans are in the works to equip the ships with new helos. Each icebreaker carries a 14-man helo detachment.
transmit location with resurfac-
r*orne
°n a C-130 Hercules.
n forth to the island. The science ^ar^y had brought two types of buoys es'gned to “flow” beneath ice floes
^8- The buoys were recovered the st day they were used; but, the k Xt day> winds held floes over the u°ys and the ship was unable to re, er them. The scientists completed e'r missions on 26 March and flew Gambell the next day to return t . Seventeenth Coast Guard Dis- j 'g Commander, then Rear Admiral p ^ ' Hayes, and his party joined the ar Sea off Gambell to observe her
progress. The admiral stayed on board until 29 March when the helicopters flew him and his party back to Gam- bell. Then, the ship’s navigators laid a direct rhumb line for Unimak Pass and the ship’s return passage.
The ship had been traveling in ice about two feet thick for most of her stay in the pack. She broke her heaviest ice—up to four feet thick and with pressure ridges—120 miles southeast of St. Matthew.
Captain Cueroni and Commander Howell were enthusiastic about the Polar Sea’s icebreaking capabilities, although the good weather and light ice of AWW 78 presented the ship with less than a challenging test. Commander Howell, however, described propeller and vibration problems similar to those experienced in the Polar Star. He said that “while we never lost pitch control, it did take increasing hydraulic pressures to make pitch changes.”
The Polar Sea arrived in Seattle on 7 April and has remained there, tied to the pier and without propellers, ever since. Hopefully, the new repairs the Polar Sea is scheduled to commence receiving this month will free her for unlimited icebreaking operations.
Coast Guard cebreaker Support
Facility
By p
qo0rnrnander D. G. Langrock, U.S. Coast Guard, Executive Officer, U.S. st Guard Icebreaker Support Facility
Th •
ca lA outstanding operational t0^abil'ties and the high-powered au- Poj ated engineering plant of the ar-class icebreakers have been dis- ed. But how is the Coast Guard
number of auxiliary systems requires a substantial increase in maintenance requirements.
The Coast Guard recognized these requirements during the conceptual
going to keep these ships operational? These ships have nine times the horsepower of the Wind-class icebreakers and have twice the displacement; and the associated increase in the size and
The Polar-class icebreakers are by far the biggest-ever ships to serve that function for the United States. And despite the engine problems which have kept the ships in port far more than expected, the perhaps-symbolic bird above is a seagull—not an albatross.
U.S. COAST GUARD (N.E. ROLL)
design and manning studies which preceded the construction of these ships and planned for additional shore support. Originally, the Coast Guard planned to rotate three crews between two ships. This approach had the advantage of keeping each crew member’s time at sea consistent with the number of days at sea for personnel assigned to other cutters while providing an augmented work force for maintenance work when the ships were in port. Additionally, it allowed the assigned personnel to receive specialized training on shipboard equipment, to attend service schools, and to take leave, all without adversely affecting the manning of the required billet levels on the two icebreakers.
The three-crew concept has been dropped, at least temporarily, due primarily to budgetary reasons. However, the need for additional shore support exists.
In April of this year the Icebreaker Support Facility (ISF) was organized as a separate command under the 13th
Coast Guard District in the ships' home port, Seattle. The command is composed of 14 enlisted and officer billets. Many of those assigned to the ISF have served in one of the Polar- class breakers. It is intended to keep the staff well loaded with personnel who have had Polar-class experience in order to have a staff that is familiar with all aspects of the ships’ operational and engineering problems.
Set up to support a particular class of ships this organization is unique in the Coast Guard. The ISF does not act as the operational commander for the ships, nor is it in the chain of command between the ships and the district commander. Essentially it provides designated support services for the Polar icebreakers in three areas: engineering maintenance, logistics, and personnel management. Without support in these areas the ships will not be able to meet their operational commitments on a long-term basis.
The ships’ large engineering plants require an extensive preventative maintenance program to keep their equipment functioning. The ISF has the responsibility of coordinating and maintaining the preventative maintenance system for the ships. Initially’ the ships kept all the preventative maintenance current, but this Pr0" gram requires more man-hours than the ships’ crew is capable of providing. This change was required in spite of the fact that, due to propeller problems, the ships have not operated as much as they eventually will to meet our nation’s icebreaking needs.
Presently the Icebreaker Supp°ft Facility staff is categorizing the pre' ventative maintenance items into thrc^ different groups. The first group W1 be the responsibility of the ship, c^e second will be performed by ISF Pef' sonnel, and the third will be Per formed by commercial contractors either at dockside or shipyard avail abilities. The problem is comple*' First, the work items assigned to the ships’ crews and to ISF personnel muSt be within the man-hours and spe
:
I
I
pities available at the commands, k c°nd, the items to be accomplished y commercial contractors present scheduling, contracting, and other re- ated problems due to the limited t'rne the ships will be in their home P°tt. Crews of other Coast Guard ice- bakers have been substantially larger and essentially all of the preventative Maintenance was accomplished by
em. The only work that normally ad t0 be contracted for involved r°utine docking, modifications, and bpair work. (A Wind-class has a crew 0 about 170 and a Polar’s complement is about 140, and the new baker is at least twice the size and nas a lot more machinery.) It is now aPparent that a great deal of the Po- ars work will have to be ac- ^Mplished with outside assistance.
e ISF will assist the district in deVeloping specifications, inspecting, and contracting for the contractor- SuPported preventative maintenance ar,d repair work.
In the area of logistics, the ISF will
assist the ships in preparing requisition documents, doing leg work in locating parts, and in staging parts and equipment for loading onto the vessels. This will be an especially important function when the ships are at sea. The ISF will handle the more difficult items to procure while the ship will handle normal MILSTRIP procurement items. And, as there are numerous repair parts unique to the Polar- class ships which have long lead times, the ISF will become an inventory control point for these items.
The ISF’s third principal area of responsibility is personnel management. The ISF will assist the ships in maintaining their current status with regard to specialized training for the crew. It will obtain quotas for both commercial and service schools. In some areas, it may be necessary for the ISF to set up specialized training for crew members where none is presently available. The ISF will assist the ships with processing personnel as they report for duty to ensure that physical examinations, housing, and normal administrative paperwork are in good order prior to departing on a long deployment.
Although the ISF is in its early stages of development, it has already relieved the ships of some of their work load and started many programs which will be of valuable assistance. Exactly what form ISF will take in the future and whether the staff is large enough to perform all of its functions have not been established. However, it is apparent with larger more sophisticated ships and reduced manning levels that the old methods of support are not sufficient. The contract for the Coast Guard’s new 270-foot medium endurance cutters (MECs) has been awarded, and it will not be long before the first ship in the class is delivered. These ships will have small crews, will be highly sophisticated, and also will need additional shore support. The Icebreaker Support Facility could well be a model for a similar support plan for the 270' MEC class.