by Max Barry

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by Pig farm. . 3 reads.

Pig Farm Space Program - Space Without Computers!

Pig Farm has built a remarkably robust space program for a nation built around pig farming. The primary objective is to track their livestock and crops using remote sensing, but they also use it to inspire their children and carry out other missions. They have put people into space and recovered them successfully.

The nation prefers low-tech approaches and by national policy does not use digital computers or networks. The space program therefore uses radar, radio, television and precise optical systems, and depends on analog systems to control their vehicles.

For space access, agency tinkerers who worked part-time in propane tank sales chose to use big dumb boosters (BDB). Pig Farm BDBs are low-efficiency, pressure-fed rockets that use kerosene/liquid oxygen engines and depend on low part counts and economies of scale to get payloads to orbit cheaply and efficiently. To increase mass fraction, Pig Farm BDBs break from traditional BDB practice (at the cost of some complexity) by using four stages, recovering the first, second and fourth (which is integrated with the payload), and expending the third. (Note: to enable a recoverable second stage, first stage separation is extremely low, at about ten thousand meters - watching a Pig Farm launch out of the waters of Lake Runoff is exciting!)

Their current "UPPERWINDOW X" satellite has a high-resolution black and white (B&W) still film camera, three medium-resolution video cameras (Red-Green-Blue filtered), and a small low-resolution black and white video camera for public relations (PR). Typical vehicle radio downlink is a single video signal with the RGB cameras and a telemetry (TLM) channel interleaved. Alternately, the PR real-time full-motion video signal or a public affairs advertising (AD) image may be downlinked non-interleaved. Pig Farm typically downlinks RBG+TLM channels over Pig Farm, RBG+PR over licensed receiving stations, and PR video or AD images over everywhere else - when power permits. PR video is a way to brag about their satellite, and a typical still AD image features tourism advertisements for Pig Farmish attractions.

High-resolution B&W still film can be returned seven times per mission, six film canisters via small return capsules, and one with the vehicle if it returns successfully. The re-entry vehicles and the satellite itself are made of aluminum. Wood (native birch cut across the grain) is used as the re-entry shield.

Mission orbits vary, but tend to be lower than the typical 705km orbit. Mission duration is designed for one year, although Pig Farm will keep satellites in orbit as long as they are serviceable, even after all the film is used up. This results in having satellites orbiting with multiple system and sensor failures, including the infamous UPPERWINDOW V, which is five years old and only the red-filtered camera and AD image still works (the AD image advertises "Maude's Trout Fishing" in Hog Holler, which closed a year ago).

The Pig Farm space agency licenses partners (nations or companies) for a fee, and in return will activate the data downlink over their coverage area. Part of the license arrangement is an arrangement where Pig Farm and licensed downlink stations exchange data to get global coverage. Licensee use of the high resolution B&W camera is by special arrangement only and is not covered in the basic license agreement.

The Pig Farm space agency sells all of its imagery (some exceptions made for national security). Since they do not have computers or network, they send out a catalog, microfiche browse is available onsite or via mail for a reasonable fee, and a phone help/order line is available. Some enterprising farmers and the Pig Farm University maintain their own downlink stations as the downlink, but this is not common.

The Pig Farm space program has a single uplink/downlink station on the peak of Mount Swine outside of Farm House City, elevated for the best reception, with unobstructed horizon-to-horizon view. Command pulse trains are sent up at least once a day. The onboard analog control system has a limited number of activation routines, but once set, each is good for three days. For re-entry or return of a film capsule, the command pulse train is sent up on one orbit and the vehicle/capsule reenters on the next pass. All re-entries are to water; if the flotation bags don't work and the vehicle is not recovered quickly, water will leak into the electronics/sensor bay and ruin the equipment.

Pig Farm equipment is simple, robust, highly reliable, and relatively cheap, although it is much larger and heavier than equivalent platforms in use by other countries. Recovery of the film capsules are only successful about three quarters of the time, the first stage nine tenths of the time, the second stage a third of the time, and the fourth (the satellite) about a quarter of the time. It is not unusual to have command or control issues, and the imagery itself is only of low-to-moderate quality, although the low-resolution PR camera video is quite popular, even in high-tech countries. Regardless, the program is judged useful and effective enough to continue.

[OOC: Pig Farm's UPPERWINDOW Program is very roughly equivalent to the 1970's US Landsat Program, with a bit of 1960's Corona thrown in. UPPERWINDOW V is the rough equivalent of Landsat 5.]

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