Colony ship (World Enough and Time)

A colony ship was travelling from Mondas to pick up colonists. When the ship almost traversed into a black hole, the crew experienced the effects of time dilation, where time on the lowest decks of the ship was travelling faster than on the upper decks.

Layout
The ship was approximately 400 miles long and around 100 miles wide.

Decks
The ship contained over a thousand decks, each of which presented a Mondasian environment. These included:
 * 0000 - The main control deck. (TV: World Enough and Time)
 * 0502 or 0503 - A deck containing a solar farm, complete with windmill. (TV: The Doctor Falls)
 * 0507 - A deck containing the largest of the ship's solar farms. (TV: World Enough and Time) The locals here were saved by the Twelfth Doctor, Bill and Nardole. (TV: The Doctor Falls)
 * 1056 - An urban deck, containing various apartment blocks and a hospital. (TV: World Enough and Time) Eventually turned into a Cyber-factory. (TV: The Doctor Falls)
 * Other floors mentioned on the lift scanner are: 1052, 1051, 1050, 1049, 1048, 1047, 1046, 1045, 1044, 1043, 1042, 1041, 1040, 1039, 1038, 1037, 1036, 1035, 1034, 1033, 1032, 1031, 1030, 1029, 1028, 1027, 1026, 1025, 1024, 1023, 1022, 1021, 1020, 1019, 1018, 1017, 1016, 1015, 0951, 0950, 0949, 0948, 0947, 0946, 0945, 0944, 0943, 0942, 0941, 0940, 0939, 0938, 0937, 0936, 0935, 0934, 0933, 0932, 0931, 0930, 0929, 0928, 0927, 0926, 0925, 0924, 0923, 0922, 0921, 0920, 0919, 0918, 0917, 0916, 0915, 0914, 0913, 0912, 0911, 0910, 0909, 0908, 0907, 0906, 0905, 0904, 0903, 0902, 0901, 0900, 0899, 0898, 0897, 0896, 0895, 0894, 0893, 0892, 0891, 0890, 0889, 0888, 0887, 0886, 0885, 0884, 0737, 0736, 0735, 0734, 0733, 0732, 0731, 0730, 0729, 0728, 0727, 0726, 0725, 0724, 0723, 0722, 0721, 0720, 0719, 0718, 0717, 0716, 0715, 0714, 0713, 0712, 1711, 0710, 0709, 0708, 0707, 0706, 0705, 0704, 0703, 0702, 0701, 0700, 0699, 0698, 0697, 0696, 0695, 0694, 0693, 0692, 0691, 0690, 0689, 0688, 0687, 0686, 0685, 0684, 0683, 0682, 0681, 0680, 0679, 0668, 0667, 0666, 0665, 0664, 0663, 0662, 0661, 0660, 0659, 0658, 0657, 0656, 0655, 0654, 0653, 0652, 0651, 0650, 0649, 0648, 0647, 0646, 0645, 0644, 0643, 0493, 0492, 0491, 0490, 0489, 0488, 0487, 0486, 0485, 0484, 0483, 0482, 0481, 0480, 0479, 0478, 0477, 0476, 0475, 0474, 0473, 0472, 0031, 0030, 0029, 0028, 0027, 0010, 0009, 0008 and 0007. (TV: World Enough and Time)
 * Other floors mentioned on the lift level indicator are: 0995, 0994, 0993, 0992, 0991, 0990, 0989, 0988, 0987, 0986, 0985, 0984, 0983, 0982, 0981, 0980, 0979, 0978, 0977, 0976, 0975, 0974, 0973, 0972, 0971, 0970, 0969, 0968, 0967, 0966, 0965, 0964, 0963, 0962, 0961, 0960, 0959, 0958, 0957, 0956, 0955, 0954, 0953, 0952, 0363, 0362, 0361, 0360, 0359, 0358, 0357, 0356, 0355, 0354, 0353, 0352, 0351, 0350, 0349, 0348, 0347, 0048, 0047, 0046, 0045, 0044, 0043, 0027, 0026, 0025, 0024, 0006, 0002 and 0001. (TV: World Enough and Time)

Each level from the bottom and up would move a little slower than the one below it, due to the time differential, from proximity to the black hole. (TV: World Enough and Time, The Doctor Falls)

Crew
At take off, there were fifty crew members aboard the ship. They included Jorj: a member of janitorial staff. Following the effects of time dilation, the ship became filled with generations of lifeforms, each descended from the ship's crew.

Technology
The ship was fitted with super-fast inertia lifts and was propelled by rear thrusters. Aboard the lowest decks, evolution of technology was advanced. In order to adapt to expiring environments, an artificial evolution was devised. The Mondasian inhabitants were gradually upgraded into Cybermen. (TV: World Enough and Time)

History
The colony ship was commissioned to transfer inhabitants of Mondas, for which it was headed with a skeleton crew of 50, including the janitor Jorj. En route, it was drawn into the gravity well of a black hole. The crew sent a team of 20 to the lowermost level, floor 1056, to reverse the engines and pull the ship free. However, time dilation caused by the black hole's gravity resulted in time passing much more slowly at the upper parts of the ship, which were closest to the black hole.

Due to time dilation, the team at the bottom of the ship found that they experienced over 500 years for every day that passed on floor 0000. Thus, after reversing the engines, they and many generations of their descendants lived out their lives on floor 1056. They built an industrial civilisation, but eventually they began to run out of resources and their environment became irreversibly polluted. At one point, an expedition was sent to floor 0507 to explore the possibility of moving there, but again due to time dilation they were never heard back from again.

Eventually, the people of floor 1056 were forced to convert themselves into cybernetic humanoids to survive. At some point snuck on board and lived on floor 1056 as "Mr. Razor", the caretaker of the hospital people went to be upgraded. The prototypes would venture to the upper floors to take the rest of the crew members for conversion, leaving only Jorj as he wasn't completely human.

Eventually, the Twelfth Doctor,, Bill Potts and Nardole picked up Jorj's distress signal. (TV: World Enough and Time)

On Floor 0507, there resided a group of farmers who possessed rifles. They were faced by the prototypes that had travelled to their floor from 1056. They spent the night shooting them down, then stringing them up on wooden crosses during the day. They were plagued by these "cyber scarecrows" (as one child called them) for an unknown amount of time - they had left floor 1056 for several hundred from their perspective. One day, a shuttle raft blasted through the floor, containing the Doctor, a cyber converted Bill Potts, the Master, Missy and Nardole. With the Doctor injured, Nardole rallied the town over the coming weeks to prepare for a Cyberman invasion; the prototypes were merely the advance guard. As such, the siege of floor 0507 began. Nardole hacked the floor to ignite certain fuel lines around the floor to fool the Cybermen their technology was a threat to the Cybermen. (TV: The Doctor Falls)