JANUARY2021|COMPUTERSHOPPER|ISSUE395
programmed forwheel breaking,
vastly reducingthetime thatthis took.
WELL-KEPT SECRET
Bletchley Park had become avital resource to
thewar effort, andhad tobe protected atall
costs. Staff were sworn to secrecy, andnobody
talked aboutwhat they did.Infact,as recently as
afew yearsago, amarriedcouple found outthat
they both worked at Bletchleyatthe sametime.
Tokeep thesite secret, thewirelessroom
originally set upin themansion’s water tower
andgiven thecodename ‘Station X’was moved
to nearby Whaddontopreventthe largeaerials
drawingattention. Itworked, andthe site was
bombed onlyonceon20th-21stNovember
1940 .It’sthought thesebombings were planned
for thenearby Bletchley railway section. Hut 4
(oneof thewooden buildings usedspecifically
for decodingnaval Enigmamessages)was blown
off itsbrickpillars.Workmen simplywinchedit
back into positionwhilework continuedinside.
MESSAGE RECEIVED
It’s been hotly debated as tothe extent
of thesuccessesat Bletchley Park,and
whetherornotthewarwasshortenedbytwo
years or more.This kindoftalk isimmaterial, as
it’s impossible towork these things out. What
we do knowisthatthe code-breaking was a
massivesuccessandenabled theAlliesto read
secret German transmissionsfromthelowliest
train station all theway uptothosesentby
AdolfHitler.
Thereare clearexamplesof wherethework
made astaggeringdifference tothe wareffort,
particularly intheNorth Atlantic, whereGerman
U-boats targeted merchant shippingboats
bringing supplies to the UK. “You couldargue
that itmadethe difference intheNorth
Atlantic,”says SimonGreenish,directorof the
Bletchley ParkTrust.“If not for Bletchley, Britain
couldhave beenstarvedout.”
Oneofthemost amazing aspectsof the
work carried out atBletchleyisthe number of
messagesthatwerebeingdecodedandsenton
forprocessingbymilitaryintelligence.Atitspeak
6,000messagesadaywerehandledbytheteam.
“Theycouldseethebreadandbutterofwhat
wasgoingoninGermany,”saysGreenish.
“Everythingthatcouldbepickedupwasbeing
decoded.”Alotofitwaspurejunk,butthe
military personnelhadeverythingtheyneeded
andcouldfilterthroughtheinformationforany
detailsthatcouldgivetheAlliesanadvantage.
Forexample,anorderto movevastquantitiesof
fuelfromatrainstationlettheAlliesknowthat
theGermansmusthaveV-2rocketsthere,and
thesitemustbebombed.
BreakingEnigmaenabledtheAlliestoplan
andwinimportantbattles,suchastheonein
NorthAfrica. “Bletchley wasfeedingMontgomery
[information about] what Rommel wasupto,”
says Greenish. This information meant Monty
had the upper hand over Rommel andknew
everythingaboutthesituationintheAxiscamp.
ItwasvitalinthevictoryatElAlameinandthe
defeatoftheGermanArmyinAfrica.
GettingaccesstotheEnigmamessagesgave
theAlliesconfidenceintheirtacticsandthe
information theyreceived. They oftenintercepted
messages from theGermans thatstatedEnigma
wasstillsecure. Before the D-Dayinvasion of
Europe, the Allies knew the German Army had
fallen for their misinformation about an army
gathering in Kentpoisedtoattack Calais.
Regardless of arbitraryfigures,it’sclear
thattheworkatBletchleyParkplayeda
significantroleintheAllies’wareffortand
helpedustodefeattheGermanArmy.This
incredibleleapforwardintechnologyalso
meantthatBritainwas,forawhile,atthe
forefrontofcomputertechnology.
THEFALLOFTHEPARK
Oncethewarwasover,therewasnoneedfor
the Park to continue in the same vein. The 12,000
personnelwerelet go,and all maintained their
secrecy oath. Thescientists who worked there
mostly wenttowork for thenew Government
Communications Headquarters (GCHQ).
This wasn’t goodnewsfor the Park,asthe
buildingswereabandoned and much of the
equipment was destroyed. Due to the secrecy of
the project, much of the work at Bletchley was
kept fromthe public. “Everythingwasbroken
up,”saysGreenish.“SomeoftheColossus
machineswereusedelsewhereuntilthe1960s.
Some of the maths was kept underwraps untila
few years ago. The story was that Britain didn’t
want theworld to know how good they were at
code-breaking.”
The incredible success that the British had
–not to mention thecomputers they invented
–justdropped off the world’s radar. Whathad
happened at Bletchley Park was forgotten until
the 1970s. TheParkpassed through many hands,
even ending up as aBTtrainingcentre fora
while, before it wasalmost sold in 1991 for
redevelopment and Milton Keynes Borough
Council took overthe site, handing it over to the
newly formed Bletchley ParkTrust soon after.
Then beganthe long jobofeducating theUKand
theworld about how important thesite really
was, as well as redeveloping and repairing it. It’s
this job that’s crucial now.
Abig part of Bletchley Park’sproblems were
due to the high levels of security and secrecy
surrounding it.Bletchley Park wasall about
pure technology andpuremathematics, but
Hut 6iscurrently in astate of disrepair andis
unsafe to enter, but it’sbeing worked on
The Ringstellung are set
at thestart of each
message andchange the
encryption. These can be
placed in any position–
threewere chosen
from aset of five
Themessageis
typedinhere
TheSteckerbrett
(plugboard)isusedto
furthercomplicatethe
messageandaddanextra
characterswapintothemix
Eachencrypted
characterislituphere
The Enigma
machine
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