What are the rules about altitudes?
The altitudes of aircraft over your area can vary according to:
- the airport the flight is coming from or going to
- whether the aircraft is coming in to land, taking off or in level flight
- the specific requirements of the flight path
- the need for air traffic control to maintain vertical separation between aircraft.
There are no regulations setting out minimum altitudes for aircraft in the course of taking off or landing at an airport.
Variation in departure altitudes
You may observe differences in the altitudes of departing aircraft. Aircraft have different climbing abilities depending on factors such as the type of aircraft and its weight, how heavily laden it is, and even the meteorological conditions at the time.
Large jets such as Airbus A380s will climb more slowly than smaller, lighter aircraft because they are so much heavier. A380s are frequently used for long-haul non-stop flights and in these circumstances will be fully laden with fuel. This adds to the weight and further compromises climb performance. When two aircraft of the same type are observed to have different climb rates this is usually because one is heading for a closer destination than the other, and is therefore carrying less fuel weight.
Atmospheric conditions can affect climb rates. For example, when it is hot and humid the air is less dense. This affects the “lift” of an aircraft and it will take longer to climb in these conditions.
Minimum altitude for level flight
The Civil Aviation Safety Authority have regulations for how low aircraft can fly. These regulations require pilots fly no lower than 1,000 feet (ft) over built-up areas, or 500 feet over any other areas, unless they are landing or taking off.
Aircraft may be able to fly below these heights in certain situations. More information is available on the CASA website.