![Os2u planes in echelon formation 1943](https://upload.wikimedia.org/wikipedia/commons/6/6f/Os2u_planes_in_echelon_formation_1943.jpg)
An echelon formation () is a (usually
military
A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. It is typically authorized and maintained by a sovereign state, with its members identifiable by their distinct ...
) formation in which its units are arranged diagonally. Each unit is stationed behind and to the right (a "right echelon"), or behind and to the left ("left echelon"), of the unit ahead. The name of the formation comes from the French word échelon, meaning a rung of a ladder, which describes the shape that this formation has when viewed from above or below.
Military formation
Use of the formation dates back to ancient
infantry
Infantry is a military specialization which engages in ground combat on foot. Infantry generally consists of light infantry, mountain infantry, motorized infantry & mechanized infantry, airborne infantry, air assault infantry, and marine i ...
and
cavalry
Historically, cavalry (from the French word ''cavalerie'', itself derived from "cheval" meaning "horse") are soldiers or warriors who fight mounted on horseback. Cavalry were the most mobile of the combat arms, operating as light cavalry ...
warfare, as an alternative to
column
A column or pillar in architecture and structural engineering is a structural element that transmits, through compression, the weight of the structure above to other structural elements below. In other words, a column is a compression member. ...
,
line-abreast, or
phalanx
The phalanx ( grc, φάλαγξ; plural phalanxes or phalanges, , ) was a rectangular mass military formation, usually composed entirely of heavy infantry armed with spears, pikes, sarissas, or similar pole weapons. The term is particularly use ...
(box) formations. One of its earliest uses was at the
Battle of Leuctra
The Battle of Leuctra ( grc-gre, Λεῦκτρα, ) was a battle fought on 6 July 371 BC between the Boeotians led by the Thebans, and the Spartans along with their allies amidst the post- Corinthian War conflict. The battle took place in the vici ...
, when the
Thebans
Thebes (; ell, Θήβα, ''Thíva'' ; grc, Θῆβαι, ''Thêbai'' .) is a city in Boeotia, Central Greece. It played an important role in Greek myths, as the site of the stories of Cadmus, Oedipus, Dionysus, Heracles and others. Archaeolog ...
attacked the Spartan right with a column 48 men deep while their weaker center and right were repelled. The echelon formation may have been used by
Hannibal
Hannibal (; xpu, 𐤇𐤍𐤁𐤏𐤋, ''Ḥannibaʿl''; 247 – between 183 and 181 BC) was a Carthaginian general and statesman who commanded the forces of Carthage in their battle against the Roman Republic during the Second Puni ...
at the
Battle of Cannae
The Battle of Cannae () was a key engagement of the Second Punic War between the Roman Republic and Carthage, fought on 2 August 216 BC near the ancient village of Cannae in Apulia, southeast Italy. The Carthaginians and their allies, led by ...
,
Alexander the Great
Alexander III of Macedon ( grc, wikt:Ἀλέξανδρος, Ἀλέξανδρος, Alexandros; 20/21 July 356 BC – 10/11 June 323 BC), commonly known as Alexander the Great, was a king of the Ancient Greece, ancient Greek kingdom of Maced ...
at the
Battle of Gaugamela
The Battle of Gaugamela (; grc, Γαυγάμηλα, translit=Gaugámela), also called the Battle of Arbela ( grc, Ἄρβηλα, translit=Árbela), took place in 331 BC between the forces of the Army of Macedon under Alexander the Great a ...
,
Frederick II of Prussia
Frederick II (german: Friedrich II.; 24 January 171217 August 1786) was King in Prussia from 1740 until 1772, and King of Prussia from 1772 until his death in 1786. His most significant accomplishments include his military successes in the Sil ...
, and the
Confederate
Confederacy or confederate may refer to:
States or communities
* Confederate state or confederation, a union of sovereign groups or communities
* Confederate States of America, a confederation of secessionist American states that existed between 1 ...
army at the
Battle of Gettysburg
The Battle of Gettysburg () was fought July 1–3, 1863, in and around the town of Gettysburg, Pennsylvania, by Union and Confederate forces during the American Civil War. In the battle, Union Major General George Meade's Army of the Po ...
.
![Echelon 1 (PSF)](https://upload.wikimedia.org/wikipedia/commons/7/79/Echelon_1_%28PSF%29.png)
The tactic still persists and is regularly employed by all branches of the modern armed forces. Tactically, echelon formations are used because of the excellent range of vision offered to each participant in the formation. In particular, it is commonly employed by armored cavalry because of the large, overlapping fields of fire that it gives to each
tank
A tank is an armoured fighting vehicle intended as a primary offensive weapon in front-line ground combat. Tank designs are a balance of heavy firepower, strong armour, and good battlefield mobility provided by tracks and a powerful engin ...
in the formation, and by combat aircraft, allowing them to communicate visually and maneuver as a single unit.
![USAF_Fighter_School_Acrojets_demonstration_team_-_1950](https://upload.wikimedia.org/wikipedia/commons/6/68/USAF_Fighter_School_Acrojets_demonstration_team_-_1950.jpg)
"Echeloning" is the name of a tactic in use by the United Kingdom's armed forces, mainly the
infantry
Infantry is a military specialization which engages in ground combat on foot. Infantry generally consists of light infantry, mountain infantry, motorized infantry & mechanized infantry, airborne infantry, air assault infantry, and marine i ...
. It consists of using a
company
A company, abbreviated as co., is a Legal personality, legal entity representing an association of people, whether Natural person, natural, Legal person, legal or a mixture of both, with a specific objective. Company members share a common p ...
to attack a set of positions. Once the first platoon in the company has reached its limit of advance (ammunition has been expended,
fatigue
Fatigue describes a state of tiredness that does not resolve with rest or sleep. In general usage, fatigue is synonymous with extreme tiredness or exhaustion that normally follows prolonged physical or mental activity. When it does not resolve ...
has become high, or casualties are mounting) another
platoon
A platoon is a military unit typically composed of two or more squads, sections, or patrols. Platoon organization varies depending on the country and the branch, but a platoon can be composed of 50 people, although specific platoons may range ...
"echelons through" it to continue onto the next position. The tactic is similar to
leapfrogging
Leapfrogging is a concept used in many domains of the economics and business fields, and was originally developed in the area of industrial organization and economic growth. The main idea behind the concept of leapfrogging is that small and incre ...
.
Echelon formations are also commonly used by civic or
riot police
Riot police are police who are organized, deployed, trained or equipped to confront crowds, protests or riots.
Riot police may be regular police who act in the role of riot police in particular situations or they may be separate units organize ...
to move crowds either to the left or right. ''En echelon'' is also used for a type of arrangement of gun turrets on ships: see .
Derived meanings
![En_echelon1](https://upload.wikimedia.org/wikipedia/commons/a/a8/En_echelon1.jpg)
The name has been adopted by the
birdwatching
Birdwatching, or birding, is the observing of birds, either as a recreational activity or as a form of citizen science. A birdwatcher may observe by using their naked eye, by using a visual enhancement device like binoculars or a telescope, b ...
community to describe the familiar V-shaped formations of flights of
geese
A goose (plural, : geese) is a bird of any of several waterfowl species in the family (biology), family Anatidae. This group comprises the genera ''Anser (bird), Anser'' (the grey geese and white geese) and ''Branta'' (the black geese). Some o ...
,
duck
Duck is the common name for numerous species of waterfowl in the family Anatidae. Ducks are generally smaller and shorter-necked than swans and geese, which are members of the same family. Divided among several subfamilies, they are a form t ...
s and other
migratory birds
Bird migration is the regular seasonal movement, often north and south along a flyway, between breeding and wintering grounds. Many species of bird migrate. Migration carries high costs in predation and mortality, including from hunting by ...
, though this more symmetric formation is more strictly defined as a
V formation
A V formation is the symmetric V-shaped flight formation of flights of geese, swans, ducks, and other migratory birds, improving their energy efficiency. Usually, large birds fly in this formation since smaller birds create more complex wind c ...
.
In geology, ''en echelon'' describes an arrangement where a set of short linear features overlap or are staggered in a line that runs obliquely to the strike of the individual features.
Echelon faults
ECHELON, originally a secret government code name, is a surveillance program (signals intelligence/SIGINT collection and analysis network) operated by the five signatory states to the UKUSA Security Agreement:Given the 5 dialects that use ...
and
en echelon veins
In structural geology, en échelon veins, "en échelon gash fractures" or "Tiger Stripes" are structures within rock caused by noncoaxial shear.
En echelon veins can be parallel or subparallel, closely-spaced, overlapping or step-like minor str ...
are examples.
In sheet material response to
shear stress
Shear stress, often denoted by (Greek: tau), is the component of stress coplanar with a material cross section. It arises from the shear force, the component of force vector parallel to the material cross section. ''Normal stress'', on the ot ...
it is typical for a series of
echelon cracks Echelon cracks are a related series of cracks in a planar structure and are a response to shearing forces in the plane of the surface. Such cracks are typically found in asphalt roadways due to aseismic creep and in other planar structures such as w ...
to form. This is commonly seen in asphalt roads subject to shear stress imposed by
aseismic fault creep.
In mathematics, the term
row echelon form
In linear algebra, a matrix is in echelon form if it has the shape resulting from a Gaussian elimination.
A matrix being in row echelon form means that Gaussian elimination has operated on the rows, and
column echelon form means that Gaussian ...
refers to a kind of
matrix
Matrix most commonly refers to:
* ''The Matrix'' (franchise), an American media franchise
** ''The Matrix'', a 1999 science-fiction action film
** "The Matrix", a fictional setting, a virtual reality environment, within ''The Matrix'' (franchis ...
where the non-zero elements are shaped in an echelon-like manner.
In
road bicycle racing
Road bicycle racing is the cycle sport discipline of road cycling, held primarily on Road surface, paved roads. Road racing is the most popular professional sport, professional form of bicycle racing, in terms of numbers of competitors, events and ...
, an echelon formation is a diagonal line of racers, which allows cooperative
drafting in
crosswinds.
References
{{reflist
Tactical formations
Ornithology
Structural geology