Missed approach point

Last updated
MAPt during a non-precision approach MDA and MDH.svg
MAPt during a non-precision approach

Missed approach point (MAP or MAPt) is the point prescribed in each instrument approach at which a missed approach procedure shall be executed if the required visual reference does not exist. [1] It defines the point for both precision and non-precision approaches wherein the missed approach segment of an approach procedure begins. A pilot must execute a missed approach if a required visual reference (normally the runway or its environment) is not in sight upon reaching the MAP or the pilot decides it is unsafe to continue with the approach and landing to the runway. The missed approach point is published in the approach plates and contains instructions for missed approach procedures to be executed at this point.

Definition of MAP depends on whether the approach flown is a precision or a non-precision one: [2] [3]

In both cases, the pilot in command must make a clear and unequivocal Yes/No decision upon arrival at the MAP point – either the runway (or its specified environment) is positively visible and accessible for landing using a safe and stabilized approach (i.e. no excessively steep bank or descent angles required), in which case the approach to landing may be continued, or else the approach must be discontinued and the published missed approach procedure must be initiated immediately.

Visual descent point (U.S.)

A concept related to the missed approach point is the visual descent point (VDP). Determination of its location is done by the designers of the instrument approach procedure, but typically this is a point on the final approach course of a non-precision approach, from which the aircraft would be able to continue its descent from the MDA to the runway threshold while maintaining a standard 3° descent angle while being assured obstacle clearance. [5] In other words, usually it is the point (on the profile view of the approach) where a line depicting a 3° descent angle would intercept the horizontal line at the MDA. If the pilot does not have the required visual reference to continue the descent from the MDA at this point, he/she must continue to fly at or above the MDA, and the rapidly steepening descent angle required to complete a successful landing on the runway means that a safe and successful approach becomes less likely.

The concept of VDP was developed by the FAA to encourage pilots to decide to initiate a missed approach before reaching the MAP, in a situation where the runway or its environment is not visible at a normal descent angle. Conversely, if the runway is visible at the VDP, the pilot may continue descent, following a standard descent angle to the runway, while being assured terrain and obstacle clearance. [5] The VDP is always located before reaching the MAP, and is a more useful checkpoint for making the decision whether to continue on the approach or to go around than the MAP itself. [6]

The following is the official FAA definition of VDP:

"A defined point on the final approach course of a nonprecision straight-in approach procedure from which normal descent from the MDA to the runway touchdown point may be commenced, provided the approach threshold of that runway, or approach lights, or other markings identifiable with the approach end of that runway are clearly visible to the pilot." [1]

Related Research Articles

<span class="mw-page-title-main">Runway</span> Area of surface used by aircraft to takeoff from and land on

According to the International Civil Aviation Organization (ICAO), a runway is a "defined rectangular area on a land aerodrome prepared for the landing and takeoff of aircraft". Runways may be a human-made surface or a natural surface. Runways, taxiways and ramps, are sometimes referred to as "tarmac", though very few runways are built using tarmac. Takeoff and landing areas defined on the surface of water for seaplanes are generally referred to as waterways. Runway lengths are now commonly given in meters worldwide, except in North America where feet are commonly used.

<span class="mw-page-title-main">Landing</span> Transition from being in flight to being on a surface

Landing is the last part of a flight, where a flying animal, aircraft, or spacecraft returns to the ground. When the flying object returns to water, the process is called alighting, although it is commonly called "landing", "touchdown" or "splashdown" as well. A normal aircraft flight would include several parts of flight including taxi, takeoff, climb, cruise, descent and landing.

<span class="mw-page-title-main">Instrument landing system</span> Ground-based visual aid for landing

In aviation, the instrument landing system (ILS) is a precision radio navigation system that provides short-range guidance to aircraft to allow them to approach a runway at night or in bad weather. In its original form, it allows an aircraft to approach until it is 200 feet (61 m) over the ground, within a 12 mile (800 m) of the runway. At that point the runway should be visible to the pilot; if it is not, they perform a missed approach. Bringing the aircraft this close to the runway dramatically increases the range of weather conditions in which a safe landing can be made. Other versions of the system, or "categories", have further reduced the minimum altitudes, runway visual ranges (RVRs), and transmitter and monitoring configurations designed depending on the normal expected weather patterns and airport safety requirements.

<span class="mw-page-title-main">Airfield traffic pattern</span>

An airfield traffic pattern is a standard path followed by aircraft when taking off or landing while maintaining visual contact with the airfield.

The visual approach slope indicator (VASI) is a system of lights on the side of an airport runway threshold that provides visual descent guidance information during final approach. These lights may be visible from up to 8 kilometres (5.0 mi) during the day and up to 32 kilometres (20 mi) or more at night.

<span class="mw-page-title-main">Precision approach path indicator</span> Visual aid in aviation

A precision approach path indicator (PAPI) is a system of lights on the side of an airport runway threshold that provides visual descent guidance information during final approach. It is generally located on the left-hand side of the runway approximately 300 meters beyond the landing threshold of the runway.

<span class="mw-page-title-main">Instrument approach</span> Aircraft landing procedure

In aviation, an instrument approach or instrument approach procedure (IAP) is a series of predetermined maneuvers for the orderly transfer of an aircraft operating under instrument flight rules from the beginning of the initial approach to a landing, or to a point from which a landing may be made visually. These approaches are approved in the European Union by EASA and the respective country authorities and in the United States by the FAA or the United States Department of Defense for the military. The ICAO defines an instrument approach as "a series of predetermined maneuvers by reference to flight instruments with specific protection from obstacles from the initial approach fix, or where applicable, from the beginning of a defined arrival route to a point from which a landing can be completed and thereafter, if landing is not completed, to a position at which holding or en route obstacle clearance criteria apply."

<span class="mw-page-title-main">Missed approach</span> Emergency aircraft procedure

Missed approach is a procedure followed by a pilot when an instrument approach cannot be completed to a full-stop landing. The instructions for the missed approach may be assigned by air traffic control (ATC) prior to the clearance for the approach. If ATC has not issued specific instructions prior to the approach and a missed approach is executed, the pilot must follow the (default) missed approach procedure specified for the approach. Prior to commencing the approach, pilots can make a specific request to ATC if a missed approach may occur. Such a request may include heading and altitude instructions to avoid in-flight delays and efficiently maneuver the aircraft into position for either its next approach or a diversion to an alternate airport.

<span class="mw-page-title-main">Microwave landing system</span> All-weather, precision radio guidance system

The microwave landing system (MLS) is an all-weather, precision radio guidance system intended to be installed at large airports to assist aircraft in landing, including 'blind landings'. MLS enables an approaching aircraft to determine when it is aligned with the destination runway and on the correct glidepath for a safe landing. MLS was intended to replace or supplement the instrument landing systems (ILS). MLS has a number of operational advantages over ILS, including a wider selection of channels to avoid interference with nearby installations, excellent performance in all weather, a small "footprint" at the airports, and wide vertical and horizontal "capture" angles that allowed approaches from wider areas around the airport.

<span class="mw-page-title-main">Runway visual range</span> Measure of aircraft visual distance

In aviation, the runway visual range (RVR) is the distance over which a pilot of an aircraft on the centreline of the runway can see the runway surface markings delineating the runway or the lights delineating the runway or identifying its centre line. RVR is normally expressed in meters or feet. RVR is used to determine the landing and takeoff conditions for aircraft pilots, as well as the type of operational visual aids used at the airport.

<span class="mw-page-title-main">Crossair Flight 3597</span> 2001 aviation accident in Switzerland

Crossair Flight 3597 was a scheduled flight from Berlin Tegel Airport, Germany, to Zürich Airport, Switzerland. On 24 November 2001, the Crossair Avro RJ100 operating the route, registered as HB-IXM, crashed into a wooded range of hills near Bassersdorf and caught fire. Out of the 33 occupants, nine made it out alive.

Land and Hold Short Operations is an air traffic control procedure for aircraft landing and holding short of an intersecting runway or point on a runway, to balance airport capacity and system efficiency with safety.

In aviation, vertical navigation is glidepath information provided during an instrument approach, independently of ground-based navigation aids in the context of an approach and a form of vertical guidance in the context of climb/descent. An onboard navigation system displays a constant rate descent path to minimums. The VNAV path is computed using aircraft performance, approach constraints, weather data, and aircraft weight. The approach path is computed from the top of descent point to the end of descent waypoint, which is typically the runway or missed approach point.

<span class="mw-page-title-main">Approach lighting system</span> Runway lighting installed on the approach end which extends beyond the runway

An approach lighting system (ALS) is a lighting system installed on the approach end of an airport runway and consisting of a series of lightbars, strobe lights, or a combination of the two that extends outward from the runway end. ALS usually serves a runway that has an instrument approach procedure (IAP) associated with it and allows the pilot to visually identify the runway environment and align the aircraft with the runway upon arriving at a prescribed point on an approach.

In aviation, approach surveillance radar is a type of radar instrument approach provided with active assistance from air traffic control. The only airborne radio equipment required for radar approaches is a functioning radio transmitter and receiver. The radar controller vectors the aircraft to align it with the runway centerline. The controller continues the vectors to keep the aircraft on course until the pilot can complete the approach and landing by visual reference to the surface.

<span class="mw-page-title-main">Air Algérie Flight 702P</span> 1994 air crash in England

Air Algérie Flight 702P, named Oasis and registered 7T-VEE, was a Boeing 737 owned by Air Algérie and leased by Phoenix Aviation. On 21 December, 1994, in low visibility conditions, it collided with power transmission cables and a pylon during its final approach to Coventry Airport in the United Kingdom. The aircraft subsequently overturned and damaged several houses before crashing inverted into a wooded area beyond. All five people on board were killed.

<span class="mw-page-title-main">Southwest Airlines Flight 1455</span> Aviation accident in California, USA

Southwest Airlines Flight 1455 was a scheduled passenger flight from McCarran International Airport, Las Vegas, Nevada, to Burbank-Glendale-Pasadena Airport, Burbank, California, that overran the runway during landing on March 5, 2000. The aircraft, a Boeing 737-3T5, registration N668SW, came to rest on a city street adjacent to a gas station. The National Transportation Safety Board found that the incident was due to the pilots attempting to land with excessive speed. They also found that the air traffic controller placed them in a position from which their only option was a go around. Two of the passengers were seriously injured, and there were many minor injuries. As a result of the incident, the airport installed an Engineered Materials Arrestor System (EMAS) at the east end of the incident runway. The aircraft was written off, making the incident the 10th hull loss of a Boeing 737-300. This was the first major accident in the airline's 29-year history.

<span class="mw-page-title-main">Final approach</span> Final stage in an aircrafts approach to landing

In aeronautics, the final approach is the last leg in an aircraft's approach to landing, when the aircraft is lined up with the runway and descending for landing. In aviation radio terminology, it is often shortened to "final".

<span class="mw-page-title-main">Inex-Adria Aviopromet Flight 450</span> 1975 aviation accident

Inex-Adria Aviopromet Flight 450, JP 450, was an international charter flight from Tivat in the Socialist Federal Republic of Yugoslavia to Prague, Czechoslovakia which crashed in the Prague suburb of Suchdol on October 30, 1975, at 09:20 AM. The McDonnell Douglas DC-9-32 with 115 passengers and 5 crew on board descended, under Instrument Meteorological Conditions (IMC), below defined Minimum Descent Altitude (MDA) during the final approach to Prague Ruzyně Airport RWY 25, entered a gorge above Vltava river, and was unable to outclimb the rising terrain. 75 of the 120 occupants died during the crash itself while 4 others died later in hospital. The accident remains the worst aviation disaster on the Czech Republic soil.

<span class="mw-page-title-main">Air Bagan Flight 011</span> 2012 aviation accident

Air Bagan Flight 011 was a scheduled domestic passenger flight of a Fokker 100 twinjet from Yangon to Heho, Myanmar. On 25 December 2012, the aircraft crash-landed short of the runway at Heho Airport in fog, coming to a stop in a paddy field and bursting into flames. One of the 71 people on board and a motorcyclist on the ground were killed and more than 10 people were injured.

References

  1. 1 2 Pilot/Controller Glossary. FAA. 2013-03-07. Archived from the original on 2009-09-27. Retrieved 2013-05-06.
  2. "Section 5-4-20f4. Circling Minimums". Aeronautical Information Manual. FAA. 2013-03-07. Retrieved 2013-05-06.
  3. "Section 5-4-21. Missed Approach". Aeronautical Information Manual. FAA. 2013-03-07. Retrieved 2013-05-06.
  4. "Section 5-4-5j. Pilot Operational Considerations When Flying Nonprecision Approaches". Aeronautical Information Manual. FAA. 2013-03-07. Retrieved 2013-05-06.
  5. 1 2 "Section 5-4-5i. Vertical Descent Angle (VDA) on Nonprecision Approaches". Aeronautical Information Manual. FAA. 2013-03-07. Retrieved 2013-05-06.
  6. "Constant-angle Nonprecision Approach" (PDF). Flight Safety Foundation. August–November 2000. Retrieved 2013-03-03.