How turbulent is LIM-SCL typically?

Light except over the Andes crossing, where mountain-wave chop is common but short.

What is the best altitude to avoid turbulence on LIM-SCL?

Above FL380 the wave amplitude drops off. Crossings at lower levels are consistently rougher.

When is the best time of year to fly LIM-SCL?

The southern-hemisphere summer, December to February, when westerlies over the Andes are weaker.

What causes the turbulence on this route?

Mountain waves generated by strong westerly flow over the Andes ridge.

Turbulence forecast LIM → SCL. Lima to Santiago. SkyBriefing.

Lima to Santiago: what the LIM to SCL corridor looks like

Departure: Jorge Chavez International Airport, Lima, Peru
Arrival: Arturo Merino Benitez International Airport, Santiago, Chile
Great-circle distance: 2,461 km (1,329 nm)
Typical airborne time: 3h 22m
Usual cruise levels: FL330 to FL390
Initial track: southbound

Route overview

Jorge Chavez International Airport (LIM) in Lima, Peru, to Arturo Merino Benitez International Airport (SCL) in Santiago, Chile, is a great-circle distance of 2,461 km, about 1,329 nautical miles. At typical jet cruise speeds, and with an allowance for climb, descent and approach, that works out to roughly 3h 22m of airborne time. The great-circle track leaves Lima southbound and spends most of the flight in tropical air.

Leaving Lima

Lima sits on a narrow desert coastal strip with the Andes rising a short distance inland. Departures climb through a persistent marine inversion layer, and the terrain to the east shapes the routing straight away. The great-circle track leaves LIM southbound, and the first waypoint band of the flight sits close to 17.4S 75.5W. On a sector of 3h 22m, the climb to cruise takes roughly the first twenty to twenty five minutes.

Mountain wave over the Andes

The midpoint of the LIM to SCL track lies near 22.7S 74.0W, about 1,231 km from Lima, which is where the corridor spends its longest continuous stretch at cruise level. The Andes are one of the most reliable mountain wave generators in the world, and this track crosses them. The wave section is short and geographically fixed, which makes it easy to brief in advance. Cruise on either side of the ridge is generally smooth.

Cruise altitudes on this sector

Medium haul sectors typically level off between FL330 and FL390, with a single step climb once fuel burn has lightened the aircraft. Choice of level matters because turbulence is layered: a change of two or three thousand feet often puts the aircraft into calmer air, and that is one of the first adjustments a crew will request.

Arriving into Santiago

Arrivals into Santiago descend alongside the Andes. Westerly flow over the range produces mountain wave that reaches the arrival path, which is a known local effect and one crews brief before the descent. Descent normally begins around 28.0S 72.4W, roughly 615 km before SCL, and takes about half an hour from cruise level to touchdown.

Seasonal pattern

The southern hemisphere winter, roughly June to September, brings the strongest westerly flow over the Andes. December to February crossings are usually the gentler ones.

Flying this route with less worry

Turbulence on this corridor is a comfort issue rather than a safety one. Airliners are certified to handle loads well beyond anything the atmosphere produces here, crews are trained for it, and the seat belt sign is the tool that keeps the cabin settled. What this page adds is knowing in advance: the map and Calmness Score above use current WAFS forecast data for LIM to SCL, so you can see what to expect before you board.