301 – CATOBAR – IFLOLS
Improved Fresnel Lens Optical Landing System (IFLOLS)
This device is mounted on the left side of the carrier to provide the pilot with visual glidepath information during the final phase of the approach. The system displays a bright orange ‘ball’ that is dynamically stabilized to compensate for ship’s pitch, roll and heave motion. The system is normally set for a 3.5° glideslope targeting the 3-wire.
The ball appears aligned between two horizontal datum lights when the pilot is approaching on the optimum glide path. If the ball is above the datum lights the aircraft is above the glidepath. If the ball is below the datum lights, the aircraft is below glidepath.
Lens Assembly
The lens assembly is a vertical box that contains 12 fiber optic light cells. The aircraft’s position on the glidepath determines which cell is visible to the pilot. The upper cells are amber in color while the bottom two are red. If a red lens is visible, the aircraft is dangerously low.
Datum Lights
Green datum lights are mounted horizontally to the lens assembly with ten lights on each side. The position of the ball in reference to the datum lights provides the pilot with glideslope information. If the ball is illuminated above or below the datums, the aircraft is high or low respectively.
Cut Lights
Mounted horizontally and centered above the lens box are four green cut lights. The cut lights are used by the LSO to communicate with the aircraft during Zip Lip (no radio) operations. As the aircraft approaches the groove, the LSO will momentarily illuminate the cut lights to indicate a “Roger ball” call. Subsequent illumination of the cut lights indicates a call to add power.
Waveoff Lights
Waveoff lights are mounted vertically on each side of the lens box. These red lights are controlled by the LSO. When they are illuminated, the aircraft must immediately execute a waveoff. The LSO will initiate a waveoff any time the deck is foul (people or equipment in the landing area) or an aircraft is not within safe approach parameters.
Long Range Laser Lineup System
The Long Range Laser Lineup System uses eye-safe, color-coded lasers to provide visual lineup information to approaching aircraft. These low intensity lasers are projected aft of the ship and are visible out to 10 miles at night.
The color of the laser light and rate at which they flash indicate the pilot’s position in relation to the angled deck’s centerline.
- Steady Amber – within 0.5 degree of centerline
- Steady Green – 0.5 – 0.7 right of centerline
- Slow Flashing Green – 0.75 – 4.0 degrees right of centerline
- Fast Flashing Green – 4.0 – 6.0 degrees right of centerline
- Steady Red – 0.5 – 0.7 left of centerline
- Slow Flashing Red – 0.75 – 4.0 degrees left of centerline
- Fast Flashing Red – 4.0 – 6.0 degrees left of centerline
