User:The Duke of Waltham/Palace of Westminster workshop/List of interruptions in the operation of Big Ben

List of interruptions in the operation of Big Ben

The south dial being cleaned on 11 August 2007, while the Great Clock was stopped for maintenance works. [Abseilers descend from the belfry to clean the glass dials roughly every five years, usually while the clock is running.]

[insert here complicated juggling act of an introduction] (Big Ben is a clock tower at the north end of the Palace of Westminster, the seat of the British Houses of Parliament in central London. The name is popularly used for the tower itself (officially named the Elizabeth Tower), the turret clock it houses (formally the Great Clock of the Palace of Westminster) and the clock's principal bell (the Great Bell of Westminster), to which the nickname was first applied in the 19th century. [Guide, p. 3] The latter is responsible for striking the hours ... quarter bells ... ring the Westminster Quarters (or Chimes) ... transmitted by the BBC)

BACKGROUND SECTION FOR NORMAL OPERATION OF THE CLOCK?

Constructed in the 1840s and 1850s, Big Ben began operation in stages over the summer of 1859: the clock started running on 31 May, the hourly strikes commenced on 11 July and the chimes were first rung on 7 September. Soon afterwards, on ?????, the Great Bell cracked (because of a heavy hammer and perhaps faulty casting of the bell), necessitating [various arrangements]. The clock has since become famous for its reliability, and mechanical failures have been rare. The only significant breakdown of the clock occurred in 1976, when the chiming mechanism disintegrated and required extensive repairs.

The majority of stoppages of the clock have been minor and were caused by bad weather or human error. The clock's large size makes it vulnerable to atmospheric conditions, and although its design largely insulates it from external forces like the wind ... extreme temperatures have affected its operation ... icy snow on the ledge ... flock of starlings ... hammers and ladders ...

... low temperatures have also caused [failures] in chiming ... there have been many cases of muffled frozen hammers ... other than malfunction, the bells have been silenced in wartime and on important funerals ... Great Bell tolls for funerals of kings ... Wartime blackout also caused the illumination of the dials to be turned off.

There have also been scheduled stoppages of the clock. Since the introduction of Daylight Saving Time (DST) in 1916, the clock has generally been stopped twice a year for the switch to or from British Summer Time. Engineers take advantage of these occasions to inspect the clock's mechanism and conduct repairs, and the clock remains stopped and dark for several hours to allow for those works to be carried out. The clock has also been stopped on several occasions for scheduled maintenance works.

This list includes stoppages of the clock (criteria for inclusion?), with the exception of DST switches, and deviations from the normal ringing patterns of the bells. All times given are local (GMT or BST).

List of interruptions

• 1 October 1859: The Great Bell cracked ... clock silent ... temporary chimes introduced in 1860 ... Great Bell and chimes restored in 1862 (MacDonald, p. 178)
• May 1910: Bell tolled for the first time, for the funeral of King Edward VII
• 1916: For two years during the First World War, the bells were silenced and the clock face darkened at night to prevent attack by German Zeppelins.
• 1934: Clock out of service for major overhaul; Great Tom broadcast time from 30 April to 3 July. (MacDonald, p. 179)
• February 1936: Great Bell tolled for the funeral of King George VI. (MacDonald, p. 180)
• 23 September 1936: (MacDonald, p. 128–129)
• 1 September 1939: Although the bells continued to ring, the clock faces were darkened at night through World War II to prevent guiding Blitz pilots.
• 3–4 June 1941: The clock stopped from 10:13 p.m. until 10:13 the following morning, after a workman repairing air raid damage to the clock face dropped a hammer into the works.
• 9 December 1944:
• 25 January 1945:
• 28/29 January 1947:
• 12 August 1949: The clock slowed by four and a half minutes after a flock of starlings perched on the minute hand.
• February 1952: Great Bell tolled for the funeral of King George VI. (MacDonald, p. 180)
• 18 July 1955:
• 1956:
• 28 May 1957:
• 30 October
• 31 December 1961: The clock slowed due to heavy snow and ice on the long hands, causing the pendulum to detach from the clockwork, as it is designed to do in such circumstances, to avoid serious damage elsewhere in the mechanism – the pendulum continuing to swing freely. Thus it chimed in the new year 10 minutes late.
• 30 January 1965: The bells were silenced during the funeral of statesman and Prime Minister Winston Churchill.
• 22 June 1966:
• 9 January 1968:
• 5 August 1976: First and only major breakdown. The air brake speed regulator of the chiming mechanism broke after more than 100 years of torsional fatigue, causing the fully wound 4-ton weight to spin the winding drum out of the movement, causing a large amount of damage. The Great Clock was shut down for a total of 26 days over nine months – it was reactivated on 4 May 1977; this was the longest break in operation since its construction. During this time BBC Radio 4 had to make do with the pips. Although there were minor stoppages from 1977 to 2002 when the maintenance of the clock was carried out by the old firm of clockmakers Thwaites & Reed, these were often repaired within the permitted two hour downtime and not recorded as stoppages. Prior to 1970 maintenance was carried out by the original firm of Dents and since 2002 by Parliamentary staff.
• 30 April 1997: The clock stopped 24 hours before the general election, and stopped again three weeks later.
• 27 May 2005: The clock stopped at 10:07 p.m., possibly because of hot weather; temperatures in London had reached an unseasonable 31.8 °C (90 °F). It resumed, but stopped again at 10:20 p.m. and remained still for about 90 minutes before resuming.
• 29 October 2005: The mechanism was stopped for about 33 hours to allow maintenance work on the clock and its chimes. It was the lengthiest maintenance shutdown in 22 years.
• 7:00 a.m. 5 June 2006: The quarter bells were taken out of commission for four weeks as a bearing holding one of the quarter bells was damaged from years of wear and needed to be removed for repairs. During this period, BBC Radio 4 broadcast recordings of British bird song followed by the pips in place of the usual chimes.
• 11 August 2007: Start of 6-week stoppage for maintenance. Bearings in the clock's going train and the Great Bell striker were replaced, for the first time since installation. During the maintenance works, the clock was not driven by the original mechanism, but by an electric motor. Once again, BBC Radio 4 had to make do with the pips during this time.
• 17 April 2013: The bells were silenced as a mark of "profound dignity and deep respect" during the funeral of Margaret Thatcher.