10 Calculation Errors That Proved To Be Disastrous

Bridge fail

A few months back, we saw how train operator SNCF made a blunder in its calculation/desk study and how it incurred huge losses owing to the mistake. However, that got us thinking that this can’t be the only time when companies/individuals have opted to act sorry instead of playing it safe and therefore, we have compiled this list where a slight miscalculation and overlooking a simple detail has cost lives and/or millions of dollars.

10. The Millennium Bridge


The Millennium Bridge in London was opened in June 2000, however, it soon became evident that the designers had forgotten to cater for the synchronized downfall and the side swaying and as a result, the bridge was closed to install the dampers. The bridge re-opened in February 2002. Although no incident took place, but still, it gave the people walking on it the thrill of a lifetime.

9. The Sochi biathlon track

OLY-2014-BIATHLON-WOMENBefore the opening day of the Sochi Winter Olympics it was found out that the biathlon track was about 40 meters short and thank God it was the track that was short and not the swimming pool. The shortage was overcome within three days before the first event on the particular track took place.

8. Scott’s Diet Calculations

8. Scott's Diet CalculationsThis one was a horrible miscalculation that resulted in a whole team of explorers to die of starvation. Robert Falcon Scott in his 1910-1912 expedition to the South Pole, made erroneous calculations for ration requirement of his team. It later turned out that the count was 3,000 calories less than what was required and the whole team starved to death.

7. The Laufenburg bridge

7. The Laufenburg bridgeSea level varies from place to place and every country uses a sea level that is locale to itself. However, what to do when you are in a location where two different sea levels merge? Such was the case for the Laufenburg Bridge which enjoys part of Germany and part of Switzerland. The end result was difference in elevation of the two ends of bridge that were supposed to join because the designers in Germany used another sea level whereas the designers in Switzerland used another. The difference was reported to be 27 cm and the German side had to lower their part of the bridge. The changes incurred huge losses to the government

6. Stonehenge model

6. Stonehenge modelApparently, rock bands have a history with Stonehenge models; some ended up too large and some ended up as too big. Black Sabbath’s version turned out to be quite big because of a mix up between meters and feet whereas during the “This is Spinal Tap” show of a rock group, the Stonehenge megalith turned out to be small since feet were mistaken for inches.

5. Big Ben Bell

5. Big Ben BellThe House of Parliament in London houses the Big Ben bell, which cracked when it was tested back in 1857. Upon failure it was melted down and set for recasting. However, the new bell in 1859 also cracked only after three days of installation. Theories arose that blamed the size of bell whereas some took into account the composition of bell. However, the final decision came in the form of replacement of hammer with a lighter one and rotation of the bell by about one-eighth of a turn. The whole issue was not only an embarrassment for the government, but also incurred significant repair costs.

4. The Hubble Space Telescope

4. The Hubble Space TelescopeThe Hubble Telescope, after it was launched, sent back the images it took and to the scientists’ dismay, those images were a bit blurred. It turned out that the main mirror was out by about 1/50th of a human hair. Although the error was too small, yet it was ample enough to jeopardize the whole project and that would have happened if the scientists didn’t come up with a quick fix that involved making corrective glasses for the Hubble Telescope. The glasses were named Corrective Optics Space Telescope Axial Replacement (Costar).

3. The Gimli Glider

3. The Gimli GliderIt would seem that the blunder of units is a persistent mistake that keeps on happening every now and then. In 1983, an Air Canada flight that was among the first ones to employ the metric measurements found out that the crew had miscalculated the fuel quantity during refueling. Admittedly they mistook pounds of fuel for kilograms and this resulted in them getting half the fuel than what was required. Fortunately, the pilot was able to land the plane on Gimli runway after running out of fuel. This earned this particular the name; ‘Gimli Glider’.

2. The Vasa warship

2. The Vasa warshipBack in 1628, the world’s most powerful warship sank after travelling for about a mile into the maiden voyage. The accident resulted in the death of about 30 people who were on board. The warship was known as Vasa and had 64 bronze canons on board. The warship was raised in 1961 and the experts, after carrying out analysis stated that the ship was thicker on the port side as compared to the starboard side. Apparently 4 kind of rulers were used to build the ship; two were Swedish feet calibrated (12 inches) and two were calibrated in Amsterdam feet (11 inches).

1. The Mars Climate Orbiter

1. The Mars Climate OrbiterThe first interplanetary weather satellite known as Mars Orbiter was lost back in 1999. The satellite was designed to orbit Mars as the name dictates however, the $125 million probe failed due to inconsistency of units. According to the investigation report; NASA used imperial units whereas the contractor used metric units.

Do you know any similar calculation mistakes? let us know in the comments section.


  1. locutas Reply

    On the day that new trains were to be “launched” into service it was discovered that no allowance had been made for the height of the air conditioning unit on top of the carriage!! consequently they were too high to fit through the tunnels.
    Red faces all round and, as far as I am aware, total cost was never reported to the paying public.
    Location: Brisbane, Australia.

  2. Shah Reply

    Something not right about the Scott diet story. 3000 calories is 1.5 days worth of food. How could they die of hunger because of this miscalculation?

  3. afj Reply

    i lost a lot of marks in school due to such mistakes. glad im not alone…

  4. itchy8me Reply

    Hubbles mirror was not a miscalculation, but rather due to an object lodged in the production apparatus causing a malformation of the mirror.

  5. itchy8me Reply

    3000 calories and just over 2 days of intake for one person. How do they starve from such a minor miscalculation considering you can go 3 weeks without food? A miscalculation of a miscalculation?

    • NazgulStig Reply

      In normal room temperature what you said is correct but not when it is freezing cold. When you are in extreme cold weather you need huge amount of calories just to maintain your body temperature and lack of calories will result in severe hypothermia and will die.

    • Christine Baillie Reply

      Perhaps it had something to do with their physical efforts.

  6. Engineer Talha Butt Reply

    Mistakes are part of learning. if one is making mistakes, it simply means he is learning

    • Anon Reply

      Sure, say this to your boss after you miscalculate something that makes the company lose thousands or millions of dollars.

  7. sharky Reply

    Tacoma Narrows Bridge in san Francisco. the designer miscalculate and forget to calculate the effect of the wind in this area the result was the bridge oscillating sideways in his natural frequency which is cased the bridge to collapse within minutes

    • Palal Reply

      Tacoma narrows is not in San Francisco, but yes, you guessed it, in Tacoma!!!! (Washington)

      So much for your geographical abilities

      • Larry Reply

        He may be from a different country. Do you know all locations in different parts of the world? Sri Lanka? Myanmar? Mozambique? STOP BEING THE BOSS; your country is not the world.

    • Margaux Reply

      Tacoma Narrows Bridge was in Washington, not California. There were signs up saying no high heels and no cats.

  8. Karl Perkins Reply

    Apparently the swimming pool at Birmingham (UK) University was designed in house. But they forgot to take into account the weight of the water and so had to shore it up with dozens of pillars. (it was on the second floor??!!)

    I heard of a similar problem with that same pool or maybe Bristol University where they built the pooll to spec. but forgot to include the thickness of tiles. As a result it was 6mm too short for official competitions.

  9. John Reply

    Heres one. In Brisbane Queensland Australia sits the Ipswich railway workshops. A large classic old shed about 500m by 800 metres. It is of the old English sawtooth roof design that lets sun in through the vertical windows in winter and not in summer due to the way it faces North. Keeping it cool in summer and warm in winter.
    Problem is it was originally built in England and dismantled and shipped to Australia and built in Ipswich.
    The workmen looked at the plans which stated “faces due north” but of course this is not the northern hemisphere as originally built but the southern instead.
    So now the building is freezing in winter and roasty in summer!!

  10. George F. Armstrong Reply

    The tide table was wrong for the Marine landing on Tarawa resulting in the loss of life by drowning of many Marines. Semper Fi

  11. Bill Harvey Reply

    Indeed, there was no disaster with the wobbly bridge either, it wobbled but was fixed and is now 14 years old with no further issues.

  12. Amanda Davey Reply

    Utterly fascinating!
    Am currently working on my grandfather’s autobiography and the need for accurate measurements is crucial and stated throughout. He and my grandmother built a model of Piccadilly Underground Station and were perplexed to find the model was out by a fraction of an inch, until he visited the site and discovered the same error (magnified of course) in the side tunnels (thankfully not the main ones). When tunnelling from two ends there is alot of scope for error and ALOT of trouble if the errors are large ones.

    • Palal Reply

      You mean you’re working on your grandfather’s biography (not autobiography) ?

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