In naval aviation

Naval aviation

Naval aviation is the application of manned military air power by navies, including ships that embark fixed-wing aircraft or helicopters. In contrast, maritime aviation is the operation of aircraft in a maritime role under the command of non-naval forces such as the former RAF Coastal Command or a...

, a bolter is when an aircraft attempting to land on the flight deck

Flight deck

The flight deck of an aircraft carrier is the surface from which its aircraft take off and land, essentially a miniature airfield at sea. On smaller naval ships which do not have aviation as a primary mission, the landing area for helicopters and other VTOL aircraft is also referred to as the...

 of an aircraft carrier

Aircraft carrier

An aircraft carrier is a warship designed with a primary mission of deploying and recovering aircraft, acting as a seagoing airbase. Aircraft carriers thus allow a naval force to project air power worldwide without having to depend on local bases for staging aircraft operations...

 touches down, but fails to catch an arrestor cable and come to a stop. Bolter aircraft accelerate at full throttle and become airborne in order to go around to re-attempt the landing.

Prior to the development of the angled flight deck, aircraft carrier landing areas ran along the axis of the ship. If an aircraft failed to catch an arrestor cable on the aft (rear) of the ship, it would still need to be stopped prior to hitting aircraft spotted (parked or taxiing) on the forward half of the deck. With aircraft spotted on the forward half of the flight deck, there was not enough room for an aircraft to become airborne again after missing the arrestor wires. Bringing an aircraft that failed to engage an arrestor cable to a stop was accomplished with either a wire "barrier", rigged amidships and raised to catch the aircraft's landing gear

Landing Gear

Landing Gear is Devin the Dude's fifth studio album. It was released on October 7, 2008. It was his first studio album since signing with the label Razor & Tie. It features a high-profile guest appearance from Snoop Dogg. As of October 30, 2008, the album has sold 18,906 copies.-Track...

, or a net "barricade" that would engage the aircraft's wings. Either method often resulted in damage to the aircraft and required time to disengage. The introduction of jet aircraft

Jet aircraft

A jet aircraft is an aircraft propelled by jet engines. Jet aircraft generally fly much faster than propeller-powered aircraft and at higher altitudes – as high as . At these altitudes, jet engines achieve maximum efficiency over long distances. The engines in propeller-powered aircraft...

 for carrier operations in the early 1950s, with their greater mass and higher approach speeds, exacerbated the problem.
The British-developed angled flight deck solved the problem of aircraft that failed to engage an arrestor wire, and created the routine option for aircraft to "bolter". By angling the landing area off the ship's axis, thus "removing" obstructions forward of the landing area, aircraft that failed to arrest – that bolter – simply accelerate down the landing area and become airborne again. Bolter aircraft then climb back to landing pattern altitude and sequence in with other landing aircraft to re-attempt the landing. These bolter aircraft are said to be in the "bolter pattern".

The British first described aircraft that failed to arrest as bolters. When an aircraft bolters on a United States Navy carrier, the Landing Signal Officer

Landing signal officer

Landing Signal Officers are naval aviators specially trained to facilitate the "safe and expeditious recovery" of naval aircraft aboard aircraft carriers. Originally LSOs were responsible for bringing aircraft aboard ship using hand signals...

 (LSO) often transmits "bolter, bolter, bolter" over the radio. United States Navy LSOs 'grade' each carrier landing attempt on a scale of 0-5. Assuming the approach was safe and at least "average", a bolter is graded as 2.5. For unsafe or below average approaches that result in bolter, a grade of 2 is assigned.