What are SALS and SSALS?
The FAA’s two short approach lighting systems — ALSF-1 cut to 1,500 ft (SALS) and a simplified 1,400-ft pattern with bars every 200 ft (SSALS) — for runways with no room for a full-length system.
SALS and SSALS are short approach lighting systems for runways that cannot take a full 2,400 to 3,000 ft system. They keep the look of the long systems — white centreline bars, a 1,000-ft decision bar and green threshold lights — in far fewer feet.
SALS is the ALSF-1 pattern cut to 1,500 ft: white barrettes every 100 ft, the 1,000-ft bar, red pre-threshold and terminating bars and green threshold lights, with no flashers. Add sequenced flashers and it becomes SALSF.
SSALS is simpler and 1,400 ft long: seven five-light white bars every 200 ft, a 1,000-ft crossbar about 70 ft wide and a green threshold bar, with no red bars. Add a short line of flashers for SSALF, or runway alignment indicator lights for SSALR. The double S marks the simplified, 200-ft-spaced family.
Frequently Asked Questions
Q1What are SALS and SSALS?
SALS is the Short Approach Lighting System and SSALS is the Simplified Short Approach Lighting System. Both are FAA approach lighting systems for runways that cannot take a full-length 2,400 to 3,000 ft system. They keep the familiar white centreline bars, a 1,000-ft decision bar and green threshold lights, but in a much shorter layout.
Q2How do SALS and SSALS differ?
SALS is the ALSF-1 pattern cut to 1,500 ft. It has centreline barrettes every 100 ft, a 1,000-ft bar, red pre-threshold and terminating bars and no flashers. SSALS is 1,400 ft long and simpler: seven five-light white bars every 200 ft, a 1,000-ft crossbar about 70 ft wide, a green threshold bar, and no red bars.
Q3What do the extra letters F and R mean?
An F means sequenced flashing lights have been added: SALSF is SALS with flashers, and SSALF is SSALS with a short line of flashers, three in the usual arrangement. An R means runway alignment indicator lights (RAIL) have been added, as in SSALR. SSALR can also be run as a subsystem of ALSF-2 in good weather.
Q4Why is a short system chosen?
Some runways have no room for 2,400 ft or more of approach lights, or the land under the approach is blocked by roads, water or terrain. A short system gives a usable pattern in the space available, but the pilot has less lead-in distance and fewer cues than with a full-length system. The approach procedure and the approved lighting together set the minimums, so follow the procedure rather than the system name.
Q5How do SALS and SSALS relate to ALSF-1 and ALSF-2?
SALS is the shortened form of ALSF-1. SSALS comes from the simplified, 200-ft-spaced family linked to ALSF-2, and the double S in the name marks it. In the other direction, an ALSF-2 can be run as an SSALR in good weather by switching off the red side rows, the 500-ft bar and the alternate 100-ft centreline barrettes.
Q6Is anything hazardous to work on?
The steady lights are on the normal series circuit rules: isolate, lock out and prove dead before work, under the permit-to-work. Where flashers are fitted (SALSF, SSALF, SSALR) they are normally capacitor-discharge units, so stored charge can remain; discharge as the manufacturer instructs before opening a head or cabinet. Approach structures are elevated and sit in the runway protection area, so access and aircraft-movement controls also apply.
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