HOME
*





Maroon (rocket)
A maroon is a type of rocket which generates a loud bang and a bright flash. It is used as an alarm or warning. The British Royal National Lifeboat Institution (RNLI) used these rockets in the past to call the crew when the lifeboat needs to be launched. Another example was as a signal on a railway, to alert oncoming trains that they must stop due to unexpected accident or track work ahead. Used by British spotters in World War I located around the cities, they would fire when German bombers were approaching. Maroons were also intended to be used by the British Civil Defense or Royal Observer Corps The Royal Observer Corps (ROC) was a civil defence organisation intended for the visual detection, identification, tracking and reporting of aircraft over Great Britain. It operated in the United Kingdom between 29 October 1925 and 31 December ... in the event of a nuclear attack - the Protect and Survive series of informational civil nuclear defence videos shows the intended usag ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Rocket
A rocket (from it, rocchetto, , bobbin/spool) is a vehicle that uses jet propulsion to accelerate without using the surrounding air. A rocket engine produces thrust by reaction to exhaust expelled at high speed. Rocket engines work entirely from propellant carried within the vehicle; therefore a rocket can fly in the vacuum of space. Rockets work more efficiently in a vacuum and incur a loss of thrust due to the opposing pressure of the atmosphere. Multistage rockets are capable of attaining escape velocity from Earth and therefore can achieve unlimited maximum altitude. Compared with airbreathing engines, rockets are lightweight and powerful and capable of generating large accelerations. To control their flight, rockets rely on momentum, airfoils, auxiliary reaction engines, gimballed thrust, momentum wheels, deflection of the exhaust stream, propellant flow, spin, or gravity. Rockets for military and recreational uses date back to at least 13th-century China. Signific ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and Northern Ireland. The United Kingdom includes the island of Great Britain, the north-eastern part of the island of Ireland, and many smaller islands within the British Isles. Northern Ireland shares a land border with the Republic of Ireland; otherwise, the United Kingdom is surrounded by the Atlantic Ocean, the North Sea, the English Channel, the Celtic Sea and the Irish Sea. The total area of the United Kingdom is , with an estimated 2020 population of more than 67 million people. The United Kingdom has evolved from a series of annexations, unions and separations of constituent countries over several hundred years. The Treaty of Union between the Kingdom of England (which included Wales, annexed in 1542) and the Kingdom of Scotland in 170 ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Royal National Lifeboat Institution
The Royal National Lifeboat Institution (RNLI) is the largest charity that saves lives at sea around the coasts of the United Kingdom, the Republic of Ireland, the Channel Islands, and the Isle of Man, as well as on some inland waterways. It is one of Independent lifeboats in Britain and Ireland, several lifeboat services operating in the same area. Founded in 1824 as the National Institution for the Preservation of Life from Shipwreck, soon afterwards becoming the Royal National Institution for the Preservation of Life from Shipwreck, under the patronage of King George IV. On 5 October 1854, the institution’s name was changed to its current name (RNLI), and in 1860 was granted a royal charter. The RNLI is a charity in the UK and in the Republic of Ireland and has enjoyed royal patronage since its foundation, the most recent being Elizabeth II of the United Kingdom, Queen Elizabeth II until her death on 8 September 2022. The RNLI is principally funded by Will (law), legacie ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Lifeboat (rescue)
A rescue lifeboat is a boat rescue craft which is used to attend a vessel in distress, or its survivors, to rescue crew and passengers. It can be hand pulled, sail powered or powered by an engine. Lifeboats may be rigid, inflatable or rigid-inflatable combination-hulled vessels. Overview There are generally three types of boat, in-land (used on lakes and rivers), in-shore (used closer to shore) and off-shore (into deeper waters and further out to sea). A rescue lifeboat is a boat designed with specialised features for searching for, rescuing and saving the lives of people in peril at sea or in estuaries. In the United Kingdom and Ireland rescue lifeboats are typically vessels crewed by volunteers, intended for quick dispatch, launch and transit to reach a ship or individuals in trouble at sea. Off-shore boats are referred to as 'All-weather' and generally have a range of 150–250 nautical miles. Characteristics such as capability to withstand heavy weather, fuel capacity, navi ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Detonator (railway)
A railway detonator (torpedo in North America) is a coin-sized device that is used as a loud warning signal to train drivers. It is placed on the top of the rail, usually secured with two lead straps, one on each side. When the wheel of the train passes over, it explodes, emitting a loud bang. It was invented in 1841 by English inventor Edward Alfred Cowper. Uses Typical uses of detonators include: * A warning, caution or stop signal in dense fog, when signals are difficult to see * A warning of a train stopped on the line ahead by an incident or accident—the train crew are usually responsible for placing the detonators * A warning of ongoing engineering works ahead * When a signaller or other railway employee requires to stop approaching trains in an emergency On a high-speed line, detonators may need to be placed on both rails. As with all explosives, detonators can become unstable over time and must, therefore, be replaced regularly. They are triggered by pressure, r ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Royal Observer Corps
The Royal Observer Corps (ROC) was a civil defence organisation intended for the visual detection, identification, tracking and reporting of aircraft over Great Britain. It operated in the United Kingdom between 29 October 1925 and 31 December 1995, when the Corps' civilian volunteers were stood down (ROC headquarters staff at RAF Bentley Priory stood down on 31 March 1996). Composed mainly of civilian spare-time volunteers, ROC personnel wore a Royal Air Force (RAF) style uniform and latterly came under the administrative control of RAF Strike Command and the operational control of the Home Office. Civilian volunteers were trained and administered by a small cadre of professional full-time officers under the command of the Commandant Royal Observer Corps; latterly a serving RAF Air Commodore. Overview In 1925, following a Defence Committee initiative undertaken the previous year, the formation of an RAF command concerning the Air Defence of Great Britain led to the provis ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]