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Your favorite feats of engineering

  1. Sep 9, 2011 #1


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    Well, what's yours?

    The Spring ABM is a favorite of mine, I find it to be an incredible piece of work. Accelerating at 100g and reaching mach 10 within 5 seconds. A missile at 30,000m could be intercepted and destroyed in 15 seconds, and the silo it was stored in had covers blown off by explosive charges, and the missile itself was launched by a piston driven by explosives.
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  3. Sep 10, 2011 #2
    Landing on the moon.
  4. Sep 10, 2011 #3


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  5. Sep 13, 2011 #4
    ...and returning safely to earth.
  6. Sep 13, 2011 #5
    Yea, getting there was one thing. But incorporating a system that would land and bring them back, that's a whole 'nother beast.

    This has got to be one of the top...sure, we build buildings and bridges and canals, and some of them are incredible, incredible feats of engineering, but using a rocket to propel humans not only into outer space but onto another celestial body? That is probably the most remarkable thing humans have ever done, technology wise, if you ask me.
  7. Sep 13, 2011 #6
    Did the first mission even have an onboard computer? The microprocessor was only invented in 1968 and the 4004 came out in 1969.
  8. Sep 13, 2011 #7
    From Wikipedia: http://en.wikipedia.org/wiki/Apollo_Guidance_Computer

    AGC [Apollo Guidance Computer] in Apollo

    Each flight to the Moon (with the exception of Apollo 8, which didn't take a Lunar Module on its lunar orbit mission) had two AGCs, one each in the Command Module and the Lunar Module. The AGC in the Command Module was at the center of that spacecraft's guidance & navigation system (G&C). The AGC in the Lunar Module ran its Primary Guidance, Navigation and Control System, called by the acronym PGNCS (pronounced pings).

    Each lunar mission had two additional computers:

    The Launch Vehicle Digital Computer (LVDC) on the Saturn V booster instrumentation ring, and
    the Abort Guidance System (AGS) of the Lunar Module, to be used in the event of failure of the LM PGNCS. The AGS could be used to take off from the Moon, and to rendezvous with the Command Module, but not to land.


    The AGC was designed at the MIT Instrumentation Laboratory under Charles Stark Draper, with hardware design led by Eldon C. Hall.[1] Early architectural work came from J.H. Laning Jr., Albert Hopkins, Ramon Alonso,[2] [3] and Hugh Blair-Smith.[4] The flight hardware was fabricated by Raytheon, whose Herb Thaler[5] was also on the architectural team.

    The Apollo flight computer was the first to use integrated circuits (ICs). While the Block I version used 4,100 ICs, each containing a single 3-input NOR gate, the later Block II version (used in the crewed flights) used 2,800 ICs, each with two 3-input NOR gates.[1]:34 The ICs, from Fairchild Semiconductor, were implemented using resistor-transistor logic (RTL) in a flat-pack. They were connected via wire wrap, and the wiring was then embedded in cast epoxy plastic. The use of a single type of IC (the dual NOR3) throughout the AGC avoided problems that plagued another early IC computer design, the Minuteman II guidance computer, which used a mix of diode-transistor logic and diode logic gates.

    The computer had 2048 words of erasable magnetic core memory and 36 kilowords of read-only core rope memory. Both had cycle times of 11.72 micro-seconds. The memory word length was 16 bits: 15 bits of data and 1 odd-parity bit. The CPU-internal 16-bit word format was 14 bits of data, 1 overflow bit, and 1 sign bit (ones' complement representation).
  9. Sep 13, 2011 #8
    Last edited by a moderator: Sep 13, 2011
  10. Sep 15, 2011 #9


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    I remember reading a gripping story (hopefully it was true) where the 1st lunar module was on its descent to the moon and Armstrong had to take over manually near the surface because the computer overloaded. His heart rate was something like 180 (or higher) and he had to move the lander laterally at the last minute to avoid landing on a boulder. There was something like 8 seconds of fuel left.
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