"Stages to Saturn - a technological history of the Apollo/Saturn Launch Vehicles". Roger E.Bilstein, 1980

Книжка о технических аспектах истории создания ракетоносителей Saturn I, IB, V (в 1960-е, в рамках лунной программы США). Главным образом, о ступенях (т.е. SM, CM, LM вообще не рассматриваются).

Цитаты:

Об испытаниях двигателя H1 - как они в камеру сгорания засовывали взрывчатку обмотанную нейлоном, запускали двигатель, ждали пока прогорит и рванёт и смотрели на последствия:

Investigators deliberately set out to introduce combustion instability in the H-l to see if the engine could recover, and if not, redesign the engine to overcome this potential danger. Late in 1963, a research group evolved a technique to induce combustion instability. Workers fixed a special boss to the face of the injector, and attached a small, 50-grain bomb to it. Enclosed in a cylindrical nylon case designed for initial cooling by engine fuel, the bomb was protected during engine start and run up but soon heated up, and after a time, it ignited. The explosion disturbed the combustion flame front sufficiently to create an unstable operating condition. It was hoped that the injector could recover from the instability in less than 0.1 second, but the Thor-Atlas injectors, uprated to 836 000 newtons (188 000 pounds) of thrust, failed to effect recovery in 8 of 16 bomb tests. After some research and development work, designers rearranged the injector orifices and added some baffles to the face of the injector. The new design worked beautifully, giving satisfactory recovery at various thrust levels and an unexpected bonus-an actual increase in engine performance.

Как в двигателе H1 разрушились лопатки турбин из-за того, что изготовитель самовольно поменял тип стали (естественно, лопатки успешно прошли дефектоскоп и были установлены в ступень, т.к. формально дефектов не имели):

The final problem taken up by the December 1966 meeting-the turbine blades-involved the inadvertent substitution of the wrong material during manufacture. During a "hot test" (actually firing the propellants) on a Saturn IB first stage, one of the H-l engines experienced failure of turbine blades. After the engines were removed and dismantled, the defective blades were found to have been cast from 316 stainless steel rather than the Stellite 21 material pecified in the production orders. An error at Haynes Stellite (a division of Union Carbide) created the mix-up. Although the quality control procedures employed x-ray analysis of each blade for flaws, penetration of welds, and differences in materials in a production batch, the x-ray check could not catch this particular mistake if all the blades were of the wrong material.

Про многочисленные проблемы с двигателем F1 (несмотря на то, что по смыслу это был увеличенный H1, масштаб всё принципиально менял):

Troubles with the F -1, however, were primarily a function of proportions, not innovations. Both engines used the same liquid oxygen and RP-l propellants, but size and performance characteristics made the F-l fundamentally different. The H-l experienced R&D problems as it was uprated in thrust. Taking proven H-l components, such as the injector, and scaling them up to F-I requirements turned out to be not only difficult but basically impossible. The job necessitated a fresh approach.

В кислородно-водородном двигателе RL-10 в качестве смазки использовался жидкий водород:

The operation of the turbomachinery incorporated another interesting design feature. The RL-l a was the first production engine to use liquid hydrogen in place of conventional lubrication systems.

В двигателе J2 в качестве теплоизоляции частей в которых находится жидкий кислород, использовали иней, которым эти части сами покрывались. С жидким водородом такое не проходило, т.к. воздух вокруг частей где он находился становился жидким и стекал, что приводило к утечкам тепла:

Designers simply took advantage of the fact that LOX components had a tendency to frost over. The frosty coating worked surprisingly well as natural insulation-so well that many components were designed without insulation from the start. The super-cold liquid hydrogen permitted no such easy design shortcuts. When air touched the extremely cold LH2 surfaces, it did not frost, but actually liquified. As a result, streaming liquid air not only became an annoyance, but also created a serious heat leak.

При сварке частей огромных баков сегменты были изготовлены настолько точно, что при их стыковке сварочный аппарат не мог нормально работать, т.к. следящая система сварочного аппарата ориентировалась (по токам Фуко) на наличие промежутка между свариваемыми частями, а он был слишком мал - воспринимался как цельная поверхность.
Предложение решить проблему, сделав края более грубыми, вызвало протесты изготовителей сегментов :) В итоге, сделали специальные канавки и модифицировали систему.

While welding the orange peel segments, a strange problem developed. The tracking system for the weld torch hinged on the detection of discontinuities produced by induced eddy currents along the seams to be welded. The exasperating torch heads wandered all over the place, however, apparently unable to follow the seams at all. Oddly enough, the trouble was traced to manufacturing standards being set too high! "Because the individual segments had been so carefully formed and sized," Bauer explained, "upon butting them together no sensible level of electrical discontinuity to the instrument developed." Some insensitive soul suggested the application of a bastard file to rough up the seams and create enough discontinuity that the tracking system could do its job. After adamant protests from the manufacturing people at Long Beach, Douglas specialists refined the tracking system to give it a much higher gain, and scarfed (grooved) the segments to provide a path for the tracking sensors to follow.


В больших цехах с высокими потолками работам сильно мешали голуби,
После консультаций с орнитологами, голубям стали подбрасывать семена с веществом, действовавшим на их нервную систему. Поев семян, голуби некоторое время сидели тихо, а затем улетали и не возвращались :)


Ornithologists consulted on the problem finally suggested some specially treated seeds to affect temporarily the pigeons' nervous systems. It worked. After pecking at the seeds, the pigeons sat quite still for a time, then finally flew off, never to return. Cheerfully, the maintenance crews refreshed the seed supply every 60 days just to make sure their feathered foes kept their distance.

Несмотря на теплоизоляцию, после полной заправки бака жидким водородом (только одной ступени S-IV) за _минуту_ простоя выкипало 1100 литров его содержимого.

By using internal thermal insulation, on the other hand, it was possible to expect only 25 percent boil-off of the tank's capacity, reducing the mechanical complications and all the other inherent drawbacks. Even with the highly efficent insulation finally developed for the S-IV and S-IVB, an LH2 tank topped off at 100 percent capacity before launch needed constant replenishment, since the boil-off required compensation at rates up to 1100 liters (300 gallons) per minute.

На фазы испытаний в программе Saturn уходило около 50% всех усилий (человек-часов и физических ресурсов).

Overall, the test phase of the Saturn program accounted for as much as 50 percent of the total effort, in terms of allotted man-hours and physical resources.

Поскольку водород горит на воздухе невидимым пламенем, это пламя, если оно где-то возникнет, трудно обнаружить. Установленным инфракрасные камеры не позволяли видеть все места. Поэтому была специальная команда людей одетых в защитные костюмы, которые проходили нужные участки держа перед собой мётлы. Если метла попадала в пламя, она загоралась :)

There was an added, perverse character about leaks that produced hydrogen fires-in daylight, the flame was invisible. It was possible to inadvertently blunder into the searing flame. As Harold Felix, who managed SACTO operations in the late 1960s, put it, "You don't want to go into a countdown of firing if you got leaks. It is a good way to blow up stages." But how to detect an invisible fire? Douglas used infrared TV cameras, but they still did not provide visibility at every angle. Just to make certain, SACTO had a special examination crew, outfitted with protective clothing and equipped with brooms. The men "walked down" the stage, from the top scaffolding to the bottom, extending their brooms ahead of them. If the broom suddently sprouted into flame, the men knew they had discovered a hydrogen leak. Still, accidents could happen, even when extra precaution was taken.

После успешных испытаний ступени S-IVB группа технарей отметила это событие бросанием в пруд своих товарищей. В финале туда же попали официантка из соседнего кафе и торговый представитель, посетивший завод:

The static test of S-IVB-20 1 was a test of men as well as machines. All the Douglas personnel were keenly anxious to have a successful demonstration of both the flight stage and the checkout equipment, and the end of the test uncapped many weeks of keyed-up emotions. A group of gleeful technicians began tossing their cohorts into the waters of a nearby pond and, in an exuberant finale, included a waitress from one of the cafeterias, along with an unsuspecting sales representative who happened to be visiting the SACTO facility.

Статические испытания были самыми дорогими. Испытания ступени S-IVB обходились в $3.2 млн за каждое.


The static tests were by far the most dramatic element of the Saturn V test program. They were also some of the most expensive. The cost of static firing the S-IVB alone came to $3.2 million for each stage.

Несмотря на то, что жидкий водород обещал большую мощность, расчёты показывали, что он не подходит для первой ступени т.к. имеет вдвое меньшую плотность чем керосин (RP-1) и потребует бака неприемлимых размеров

Although LH2 promised greater power, some quick figuring indicated that it would not work for the first stage booster. Liquid hydrogen was only one half as dense as kerosene. This density ratio indicated that, for the necessary propellant, an LH2 tank design would require a far larger tank volume than required for RP-l. The size would create unacceptable penalties in tank weight and aerodynamic design. So, RP-l became the fuel. In addition, because both the fuel and oxidant were relatively dense, engineers chose a separate, rather than integral, container configuration with a common bulkhead.

Был выбрана вертикальная сборка носителя в связи с тем, что при горизонтальной сложно обеспечить точность соединений тяжёлых тонкостенных баков.

In the early stages of talks on S-IC production, the question of horizontal as opposed to vertical assembly of the tanks and components came up. The vertical assembly mode was selected, even though a new high-bay area was required, because horizontal assembly posed problems in maintaining accuracy of joints in the heavy, but thin-walled tanks. In vertical assembly, gravity held the huge parts together, although a 198-metric-ton crane was required to hoist the parts atop each other, and to lower the completed booster back to the horizontal for final finishing.

В жидком кислороде алюминий выдерживал бОльшие нагрузки, благодаря чему стенки ёмкостей с ним можно было делать в два раза тоньше.

Immersed in liquid oxygen, the cryogenic effect on the aluminum bottles allowed them to be charged to higher pressures. They were also lighter, because the cryogenic environment permitted manufacture of the helium bottles with one-half the wall thickness of a noncryogenic bottle. Produced

В первые два лётных экземпляра первых ступеней S-IC были установлены телевизионные камеры, для контроля работы двигателей (изображение шло из опасной зоны к камерам по волоконной оптике). Вдобавок, две кинокамеры снимали происходящее внутри бака с жидким кислородом (тоже по волокну). И ещё две кинокамеры снимали момент отстыковки ступени.
После окончания работы ступени кинокамеры отстреливались и опускались на парашюте.


The first two flight stages of the S-IC also carried visual instrumentation that yielded some unique and striking images. A pair of TV cameras covered the fiery environment of engine start and operation. The cameras were tucked away above the heat shield-safe from the heat, acoustic shock, and vibration of the open engine area-and the lenses were connected to serpentine lengths of fiber optic bundles, focused on the engine area, and were protected by special quartz windows. Fiber optic bundles also provided a field of vision into the LOX tank, with a pair of motion picture cameras using colored film to record behavior of the liquid oxygen in flight. The system offered a means to check on wave and sloshing motions in the huge tank, as well as the waterfall effects of LOX cascading off internal tank structures during the boost phase. Another pair of color motion picture cameras captured the spectacular moment of separation from the S-II stage. Twenty-five seconds after separation, the color cameras were ejected in a watertight capsule, attached to a parachute for recovery downrange in the South Atlantic.


Смешиваясь с жиром и маслом жидкий кислород становится очень нестабильным в результате чем воспламенение может произойти из-за маленькой искры. Теоретически, если рабочий оставил отпечаток пальца внутри бака, может возникнуть возможность взрыва.

Mixed with a hydrocarbon like grease or oil, LOX becomes extremely unstable, and even a very small spark can ignite the capricious stuff. Theoretically, if a worker left a fingerprint on the inside of a LOX tank, the oil in the fingerprint could cause an explosive situation. So, all surfaces coming in contact with LOX were kept virtually spotless with a rating of "LOX clean".

Вдобавок к чистке сегментов, некоторые собранные узлы мыли в агрегате размером 12x12x7 метров который в шутку называли "самой большой посудомоечной машиной":

In addition to the cleaning of the segments, subassemblies like bulkheads also received the cleaning treatment in Boeing's "major component cleaning facility," jocularly known at Michoud as "the world's largest dishwasher." The dishwasher, a box 12 meters square and 6.7 meters high, was lined with stainless steel. A complete tank bulkhead was rolled in and washed down with special chemicals dispensed from revolving pipes outside and inside the dome. The revolving pipes and spraying action made the nickname inevitable.

Исходя из расчётов, чтобы взять на один килограмм больше груза, необходимо уменьшить вес первой ступени на 14 килограмм, либо второй ступени на 4-5 кг., либо третьей на 1 кг.

As the weight of the Apollo payloads relentlessly climbed during the early 1960s, NASA engineers redoubled efforts to lighten the stages. To get one more kilogram of payload, the laws of orbital mechanics required that 14 kilograms be cut from the S-IC; or four to five kilograms from the S-II; but only one from the S-IVB.

Про автоматизацию запуска ступени SIVB:

H. E. Bauer clearly remembered the occasion when men and the new machines first confronted each other. "One seasoned switch flipper came into the blockhouse after the equipment was installed; he watched the blinking lights, the scanners, the recorders-everything was working automatically, heaving out wide and endless runs of data printouts ... . " The man balefully surveyed the mechanically throbbing interloper and growled, "It's the Gray Puke!" It was not an isolated reaction. As Bauer recalls, the ghastly name stuck and became part of the permanent lexicon associated with the S-IVB stage.

Про программистскую шутку со "Скажи пожалуйста" при запуске ступени [я не верю, впрочем]:

Consider, for example, the case of the petulant computer-printer-when the machine apparently took umbrage during the automatic checkout sequence in preparation for an acceptance firing. The moment of truth for the test arrived-the signal to fire. After uncounted hours of preparation, hundreds of workers now stood by to observe the climactic moment of ignition. In the crowded blockhouse, all eyes focused on the rows of computers and monitor screens displaying their last fragments of information. Finally, the test conductor typed in his "request" to start the terminal countdown for static firing. The computer whirred, and the automatic typewriter responded with a singular reply, "Say please." Startled, the test conductor concluded he had made a typing error, and repeated his original message more carefully. The balky computer was not to be denied. "Say please," it insisted. At this point the crowd in the blockhouse began stirring restlessly. The loaded S-IVB, readied for firing, remained poised nearby with thousands of gallons of liquid oxygen and liquid hydrogen primed for detonation. People were getting tense. Reasonably certain he was only working against a faulty firing tape, the test conductor quickly decided to make one more try, rather than put it into discard and risk more precious time to put a replacement tape into operation. So once more, he entered into the machine his humble request to fire, with a polite notation at the end: "please." This time, there was no problem. "This is your programmer," the machine chattered back, "wishing you good luck." And with a roar, the rocket ignited.

Во время работы первой ступени возможные отклонения от курса (из-за порывов ветра и т.п.) умышленно не компенсируются компьютером, поскольку это может создать слишком большие нагрузки на конструкцию. Отклонения лишь запоминаются, а корректируются уже во время работы следующих ступеней.

In ascent through the atmosphere, both the Saturn IB and Saturn V were subject to possible sudden stresses from gusts, wind shear, and jet streams. If the guidance computer, acting on signals from the stabilized platform, attempted to generate compensation maneuvers during such turbulence, the added stress forces from the powerful engines as they went through extensive gimbaling motions might cause the rocket to break up. So, during the first-stage burn, the rocket flew according to a predetermined program stored in its guidance computer. If the vehicle was forced off its predetermined path, the ST-124 sensed this displacement and fed the data into the computer for later retrieval. During the second- and third-stage burns, the stored data were run through the computer and into the active guidance and control system to put the rocket back on course.

Приборный отсек (IU) доставлялся на космодром на барже по реке. Появилось предложение для экономии времени заканчивать его сборку прямо во время плавания. IBM (изготовитель) согласились и на барже была оборудована "чистая комната" для работ:

Instead, the IU was scheduled to be carried to the Cape via a barge down the Tennessee and Mississippi rivers, one of the most time-consuming elements in the IU delivery schedule. Powell and Sweat proposed finishing the IU while enroute aboard the barge and submitted their idea to their IBM counterparts, who agreed with the unlikely proposal. Because the enclosed barge was equipped with internal environmental controls anyhow, it was no great problem to set up a workable clean-room atmosphere by rigging a serie of heavy plastic shrouds for additional environmental control inside the barge canopy. Marshall and IBM specialists agreed on specific jobs to be done on the barge so that no critical areas or hardware would be subject to environmental degradation during the trip. With detailed work schedules set up, arrangements were made for delivery of key parts and supplies at designated ports along the river. In case of unanticipated needs, constant radio contact with MSFC permitted instantaneous dispatch of a light plane with emergency deliveries to any nearby airport; there, a government truck could pick them up and deliver them.


Компании исполнители привыкли (по своему авиационному прошлому) иметь свободу действий после того, как контракт подписан. Но тут им пришлось привыкать к жёсткому контролю производственных процессов NASA (в некоторых случаях - ежедневному).


Eberhard Rees admitted that the surveillance of contractor operations, as well as their management, was "somewhat sensitive from the point of view of the contractor." In many instances, contractors felt that they should be allowed to go their own way after the contract was signed. The longing for more freedom of action was evidently a legacy of the experience that most Saturn contractors had previously had with Air Force contracts. Huntsville had great technical competence; at certain managerial levels of design and manufacturing, grumped one highly placed contractor executive, Marshall maintained a one-on-one surveillance. The Air Force, he said somewhat wistfully, was "not in your pants all the time."38 But Rees maintained that loose reins on the contractor had not always worked out well from the MSFC point of view. "Consequently," he said, "it became clear that close and continuous surveillance of the contractor operation was required on an almost day-to-day basis." The extent of the surveillance was proportional to the subtleties and problems of the program, its relative position in relation to the existing state of the art, and the extent of expertise possessed by MSFC. The contractor's reaction to this aspect of NASA monitoring was not favorable at first, but eventu~lly this "penetration and monitoring" was perceived to be a mutual benefit characterized by the often repeated phrase, the "government-industry team." "Contractor penetration" was an important concept that ultimately involved the contractor's relationship with his own subcontractors.

Программа Saturn потребляла до 95% производимого жидкого водорода. В связи с увеличением объемов производства (до 190 тонн в сутки) цена упала с $20/кг в начале 1960-х до $0.35/кг (при объёмах закупок более 2.2 тонн).

The space program helped raise the production levels to 190 metric tons per day, with the Saturn program absorbing up to 95 percent of the nation's total capacity. Once a plant became operative, NASA and MSFC were eager to coordinate its production with an active test and flight series, because increased LH2 consumption was a way to save money. Producers established a price for their product that was in direct relation to the volume sold. In the early 1960s, liquid hydrogen was about $20.00 per kilogram, but the price dropped to around $2 .20 per kilogram for 450 kilograms, 45 to 65 cents per kilogram for 2250 kilograms, and leveled off at around 35 cents per kilogram for higher volumes.

Во время перевозки ступени SIV её забрызгал скунс. Возникла проблема - гигантская ступень с омерзительным запахом. Химики из Douglas Aircraft, которые нашли эффективный способ устранить запах, могут считаться невоспетыми героями программы Saturn :)

It happened early in the morning, with the loaded transporter creeping at 6.4 kilometers per hour. "At that speed nothing much should happen," Bauer reminisced, "but, incredible as it may sound, we did run over a very mature and ripe skunk." By a stroke of luck, the stage itself escaped unscathed, but the transporter remained a large, odoriferous problem-"we had a 23 1/2 ft. wide, 461f2 ft. long, 22000 lb. skunk on our hands." With other missions pending for the one-of-a-kind transporter, the Douglas Aircraft Company chemists who devised an effective deodorizer ranked high on the list of unsung heroes of the Saturn program.

Хотя NASA планировала для перевозки ступеней использовать исключительно водный транспорт, Conroy на свои деньги рискнул переделать Боинг 377 (заменив фюзеляж) и предложил новый самолёт (под названием "беременный гуппи") NASA. До того как NASA согласилась заключить с ним контракт на перевозки, денег оставалось так мало, что он занимал у приятеля на горючее чтобы долететь (зато горючее на обратную дорогу уже обеспечило NASA).
К слову, модификация того самолёта (построенная вскоре после первого) летает до сих пор: ссылка

There was little doubt that Conroy needed some firm support. His finances were in such bad shape that he reached Huntsville only by borrowing some aviation gas from a friend in Oklahoma, and MSFC agreed to supply him with enough gas to fly home to California.

Тем временем, ступени прибывали на космодром.. Во время совещания по носителю AS501 было упомянуто о 1200 проблемах, которые по плану решались со скоростью 80 в сутки:

In March 1967, an agenda for a briefing on AS-SOl, to be attended by General Phillips, included mention of 1200 problems resulting in 32 discrepancy reports. The memo to Phillips indicated that work teams had divided the problems into four separate categories and planned to work them off at an intensive rate of 80 per day. A typical problem was the discovery of an errant bolt in one of the F -1 engines and the requirement to see how it got there to make sure that nothing similar would happen again.

После первого успешного полёта Saturn V фон Браун сказал, что не верил в возможность успешного полёта такого трёхступенчатого носителя с первой попытки.

The all-up concept was undeniably successful. With AS-501 up, von Braun could finally admit his lingering doubts about it. He turned to Rudolph in the firing room at Kennedy Space Center, and told him that he thought such a completely flawless three-stage flight would never have been possible on the first try.

Во время испытательного полёта AS-502, во второй ступени отказали три двигателя J-2 из шести (тем не менее, носитель вывели на орбиту). Стали разбираться. Все испытания ступень прошла и проходила успешно. Но по данным телеметрии во время полёта была зафиксирована утечка газа из магистралей подачи жидкого кислорода..
В итоге, двигатель запустили в вакуумной камере. И получили прорыв магистрали.
Оказалось, что во время испытаний на воздухе последний превращался в жидкость (из-за близости к магистралям с жидким водородом) и эта жидкость, застревая между трубками и металлической сеткой демпфировала вибрации. В вакууме же этого не было и трубка лопалась.

Finally, Rocketdyne technicians decided to test the lines in a vacuum chamber, in close simulation of the environment where failure occurred. Eight lines were set up for test in a vacuum chamber, and engineers began to pump liquid hydrogen through them at operational rates and pressures. Before 100 seconds elapsed, each of the eight lines broke; each time, the failure occurred in one of the bellows sections. By using motion picture coverage acquired during repeated vacuum chamber tests, Rocketdyne finally could explain the failures.
The igniter fuel lines were installed on the engine with protective metal braid around the bellows section. When tested in a chamber that was not in a vacuum condition, the surrounding air was liquefied by the extremely cold liquid hydrogen flowing through the lines and was trapped between the bellows and the protective metal braid. This condition damped subsequent vibration in the fuel line. When tested in the vacuum chamber, where the environment simulated the conditions of space, there was no liquefied air to dampen the destructive resonance. A redesigned igniter fuel line eliminated the bellows sections, replacing them with bends in the line to allow for expansion and contraction during the mission.

По-поводу советских четырёх-камерных двигателей:

As ex-Soviet engineer and editor Leonid Vladimirov pointed out, the RD-I07 system took up more space than a comparable single-chamber engine of the same power. This meant that the diameter of the first stage of the launch vehicle was also larger, resulting in a considerably greater launch weight. For this reason, the jettison of the four outboard engine systems, leaving the sustainer to carry the vehicle into orbit, was an important design feature of the Russian launch vehicles. "It was, of course, a very complicated, costly and clumsy solution of the problem," Vladimirov admitted.

Про успешную интеграцию немцев в общество в американском городе рядом с ракетным производством:

Acculturation was remarkably rapid. Three years after arriving in Huntsville, the DAR medal for the best American history student in the city went to a young German girl.
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В виде html книжка есть здесь: ссылка