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Авиация и космонавтика, Почитать

17 июля 2013, 01:05 (3994 дня назад) № 3063
Книжка про полёты Аполлонов на Луну (англ.). Взята только одна тема - именно как летали туда и обратно. Про подготовку и про то, что делали после приземления - ничего нет. 432 страницы именно про полёт - весьма подробно. Выдержки:

Про то, что все пилоты лунных модулей сажали их вручную, хотя могли пользоваться компьютером (на некоторых этапах):
As low gate approached, the commander was faced with a range of options. If he was completely satisfied with the job the computer was doing, he could allow it to automatically move on to P65, which could complete the landing. No commander ever allowed that, although it is said that Jim Lovell had intended to if Apollo 13 had reached the surface. These competitive ex-test pilots, many of them experienced at landing on aircraft carriers, were happier to have some degree of control and steer the LM, and they all selected P66 before reaching low gate. P66 continuously throttled the engine to control their rate of vertical descent, and the commander could adjust this rate as conditions warranted. At the same time, he assumed manual control of the LM's attitude, which allowed him to steer the ship to a site of his own choosing. One other program, P67, was available to the commander, which gave him full manual control of the spacecraft, both the attitude and the throttle setting, but this option was never used. Both this and P65 were dropped from later versions of the LM software.
Про то, как стучали по панели, чтобы сбросить не в тему установившийся бит :)
A few minutes later as mission control watched telemetry, Haise asked Mitchell to help with a little troubleshooting. ``We'd like to do a Verb 11, Noun 10, Enter; 30 Enter; and look at that bit again.''This dialogue with the computer asked it to display a digital word which included the suspect bit on the DSKY. The crew now had a visual indication of which way the bit in question was set.``While we've got that display up, Ed,'' said Haise, ``could you tap on the panel around the Abort pushbutton and see if we can shake something loose?''Mitchell tapped around the push button and quickly saw how the bit's state responded. ``Yes, Houston, it just changed while I was tapping there.''``You sure tap nicely,'' said Haise.``I'm pretty good at that,'' replied Mitchell.
Про координаты:
It is interesting to note how longitude was handled by the software in the computers in the CSM and LM. Conventionally, longitude around a body would be expressed in the range ±180 to +180 degrees. Using the 5-digit display of the DSKY, a large longitude value could only be represented to two decimal places, e.g. +178.62 degrees. Remembering that in this primitive computer there was no provision for the decimal point to float, we can see that all longitudes would have had to be expressed to two decimal places, and around the equator, 0.01 degree represented a third of akilometre, an uncertainty that was much too large for Apollo. An elegant solution arrived at by the programmers was to stipulate that all longitudes would be handledby the computer after they had been divided by 2. The largest longitude values would now not exceed 90 degrees and could be expressed to three decimal places. This brought down the inherent resolution of the value to a mere 60 metres.
Про разницу в личностях астронавтов сидевших в лунном модуле справа и сидевших слева :)
Some observers have noted how, across the six crews who went to the surface,there seemed to be a divergence of personality types between the guy on the left of the lunar module and the guy on the right. The commander on the left was all business like, supremely focused and driven traits that tended to be carried on into their time after Apollo. The guy on the right, while equally as competent and capable,displayed a tendency to have a more varied life once the mission was over. It is unclear whether the astronaut selection process managed to tease apart two different types of pilots from what was a very homogeneous pool, or whether the experience of the mission itself set the course of their future lives. The left-hand crewmen were all mission commanders, and after Apollo they generally went into business, manage-ment or similar professions. Among the right-hand crewmen, Schmitt, who was already a scientist, became a politician; Irwin and Duke became evangelists; and Bean took up a career as an artist. Buzz Aldrin had to struggle with depression and alcoholism in the years directly after Apollo, but later became an excellent ambassador for Apollo through his many TV appearances and public lectures.The one remaining LMP in this list, Ed Mitchell, later professed a deep interest instates of being that were outside the physical consciousness, spirituality and the paranormal.
Про передачу телевизионного изображения:
When the pictures reached Earthat this non-standard frame rate, they were electronically incompatible with just about every TV system on theplanet, so the ground stations had converters to generate standard US television signals from them. The converter worked in two stages. The first simply consisted of aiming another vidicon TV camera at a small television screen. The screen displayed the images from the Moon at 10 frames per second while the camera, running at 60 fields per second, was allowed to take a valid image each time a full image was displayed, which was every tenth of a second. In other words, only one field in six from the camera contained a picture.

The second stage was to recreate the missing five fields by recording the single good frame from the TV camera onto a magnetic disk and replaying it five times to reconstruct the full 60-fields-per-second TV signal, ready for distribution to Houston. The repetition of the fields and additional lag from the second camera added to the ghostly impression left by Apollo 11's moonwalk coverage.
Опубликовано: Пётр Соболев

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