Can a passenger plane land own its own?
How often does the autopilot land?
Can a passenger jet land by itself?
Yes a plane can land by itself using a system that is often referred to as “autoland”. The pilots can program the auto-pilot to carry out the landing automatically whilst the pilots monitor the aircraft. However there are limitations as to when the autoland system can be used.
Automatic landings probably account for less then 1% of all landings on commercial flights. Many pilots actually think it’s much easier to land the aircraft manually, as monitoring the auto-pilot in the autoland stage of flight is itself very demanding with a very high level of vigilance required at all stages.
The Boeing 737 (the world’s most successful airliner in terms of the number sold) is limited to a maximum crosswind of 25kts (15kts for many airlines) when carrying out an automatic landing (Category 3 / CAT III approach). The autopilot is usually used to land in low visibility conditions when there are typically little or no winds (fog will seldom form if it’s very windy). As soon as the wind picks up, the average pilot is far better at coping with the conditions and landing the aircraft when compared to the auto pilot.
Automatic Landing Requirements
Automatic landings require a high level of automation monitoring that needs retraining every six months for professional pilots. Autolands can only be performed under strict conditions that require the certification of both the aircraft (often downgraded to no autoland capability due to technical issues), both of the pilots and the airport itself. The pilots are still required to configure the aircraft and control it’s speed and monitor its flight path. Any number of relatively minor technical issues can compromise many fail-passive auto land systems, requiring a missed approach to be carried out and then a possible diversion to an airport which is clear of fog or low cloud.
An Autoland is often referred to as a CAT III (3) approach. This refers to the category of the Instrument Landing System (ILS), which is a radio aid used to direct the pilots towards the runway on the final approach stages of flight. Not all airports have a CAT III ‘runway’ which means that not all airports can support Autoland operations. Equally, autoland capability is not a function that all aircraft have.
Categories of Instrument Landing System (ILS)
There are varying levels of ILS categories; CAT I, II & III A/B/C.
CAT I (manual landing) requires a manual landing but runway visibility must be more than 550 meters and pilots must be in sight of the runway by an altitude of 200ft.
CAT II (auto or manual landing) requires a minimum of 300 meters and 100ft
CAT IIIA (auto-land) requires a minimum of 200 meters and 50ft.
CAT IIIB (auto-land) requires a minimum of 50 meters and 0ft
CAT III C (auto-land) can potentially go down to zero visibility but this wouldn’t practically be utilised as the aircraft would be unable to taxi off the runway in zero visibility.
Can a plane take-off automatically?
No. Commercial passenger jets are not able to take-off automatically. Currently no commercial aircraft has an auto take-off capability.
To dispel the myth; the vast majority of commercial aircraft (including all Boeings and Airbus’) have no automatic take-off capability – all take-offs must be completed manually by the pilots with the auto-pilot usually engaged at around 1,000 ft above the ground.