Forum: aviation.stackexchange.com
Tags: <air-traffic-control><runways><taxiing>
Title: How do pilots identify the taxi path to the runway?
Question: When the aircraft is readying to taxi, the ATC asks them to proceed to some runway number, say runway 09. In big airports, how do the pilots identify the correct path to their runway?  Does the ATC guide them? Or do they get a map of an airport chart?

Answers:
sents: text: (Source: wikimedia.org )
text: Guiding is called progressive taxi and can be requested.
text: A follow-me car can also be used to guide the plane.
text: In some airports the follow-me car is mandatory , along with its fees.
text: In most cases the pilots use charts.
text: Either paper or electronic.
text: Some electronic charts offer a moving map feature, whereby the crew can see their position on the map.
text: Lastly, there's the new follow-the-greens ( video link ), in which the ATC programs the taxi route and the crew are then guided by smart green lights.
text: Follow-the-greens cockpit video / ATC audio in Singapore Changi can be seen here .
text: In all cases, except for follow-the-greens, the route is given.
text: It's worth mentioning that the taxiways are marked by signs as well.
text: Coming soon by 2020 is the taxi route display for pilots , in which the cockpit displays draw the taxi route via ATC datalink.
text: See possible interface here (Boeing).
answer_details: author: aviation.stackexchange.com/users/14897/ymb1
score: 45
sents: text: Almost always pilots use a chart, ie a map which shows the airport from the air.
text: Runways are numbered according to their magnetic bearing (runway 22 is roughly aligned to 220 degrees magnetic for example) while taxiways are lettered.
text: As an example see the chart for La Guardia.
text: A pilot would be given a taxi clearance which gives an end destination and a set of taxiways to take in the order they should be taken.
text: For example, a pilot parked near the fire station might be given a taxi clearance like "US123 taxi to runway 31 via Foxtrot, Alpha, Lima, Bravo and Zulu.
text: " The pilot would look at the map and see the paths to take. While taxiing there are signs on the ground which assist the pilot in navigating the taxiways.
text: Some give directions, some indicate places where ATC have to clear a crossing.
text: Occasionally a pilot will need additional guidance in which case they can ask for a progressive taxi, where ATC will guide them through the airport, but this is rare as it is very labor intensive for ATC.
text: There are also vehicles with "Follow Me" signs and lights which can be sent as well (these vehicles need clearances too).
text: It is good practice for pilots to study the ground plan for any airport they plan to visit
text: so they know what to expect when they get there, and have the plans available in the cockpit.
answer_details: author: aviation.stackexchange.com/users/1791/GdD
score: 28
sents: text: 'follow-me' cars, and progressive taxi can be used, but at a towered airport, ground control will give you that with your taxi clearance.
text: "United 2133, Laguardia Ground, taxi from the commercial ramp to runway four using taxiway alpha, echo, and bravo."
text: Using a taxiway diagram from the A/FD, you would locate your position on the plate, the taxiways in question and from there determine the route you will take.
text: In this case you'll turn left from the ramp heading northwest on taxiway A, then take a right on taxiway
text: E, then take a left on taxiway
text: B.
text: If you are unfamiliar with the airport, you can then request a progressive taxi.
text: "
text: "LaGuardia Ground, Beech 2375 X-Ray, Unfamiliar with the airport layout.
text: Request progressive taxi.
text: "
text: NOTE:
text: This will annoy controllers at busy airports if you habitually do this as it is expected that you have this information ready at hand before you call ground requesting a taxi clearance.
text: The 'follow me' vehicles are usually used for quickly routing VIP or special use aircraft to a section of the ramp e.g. Trump's 757 to a section of the ramp cordoned off for a campaign rally, etc.
answer_details: author: aviation.stackexchange.com/users/15637/Carlo Felicione
score: 6
sents: text: Very often, the instruction is in the form "Taxi to holding point RWY 24 via H, L, cross RWY 13,
text: K, B." The letters are the names of the taxiways.
text: The pilot then looks into the airport chart and follows exactly as instructed.
text: You must hold short before crossing runways, unless they are used as taxiways.
text: It is easier when the instruction is followed by "Follow the follow-me car.
text: ", then you just follow the car.
answer_details: author: aviation.stackexchange.com/users/3189/Vladimir F
score: 5
sents: text: They have the charts in the cockpit, either in electronic or in printed format.
text: As an example, see page 83 of this pdf , showing the charts for Amsterdam's airport (AMS/EHAM).
text: ATC will not only tell them to which runway to go, but also which taxiway(s) to use to go there.
answer_details: author: aviation.stackexchange.com/users/1467/Federico
score: 4
sents: text: In pilot training, it is taught to have a diagram of the airport and to study it before flight.
text: The tower is usually willing and able to help (as described in other answers: progressive taxi) but depending what airport you're at, you may have to act like the pilot in command and know what ATC is talking about.
text: You'd need to know where to taxi and you'd need to do it fast.
text: Having the diagram of the airport is necessary but you also need to know it.
text: Sometimes taxi instructions change midway through taxiing.
text: You get the point.
text: The bottom line: pilot in command has to know where and when to taxi.
text: The rest of it is nice-to-haves.
answer_details: author: aviation.stackexchange.com/users/16677/user6035379
score: 3

Summary of the answers:
Pilots have charts in the cockpit showing the airport with taxiways marked. They are also marked on the ground. Some help is also available from the tower, this is called progressive taxi. Professional pilots know to study maps of an airport before a flight to get to know the lay out. Pilots will be given information about the destination before the flight so they can plan their route and taxiways to use.
Usually, the pilots use charts, either digital or in print, and follow the taxi clearance given based on these resources. However, apart from having the relevant chart, the most important thing is for the pilot to be able to tell where and when to taxi. "Follow-me" cars are often used to guide the aircraft and guiding from the tower (progressive taxi) can be requested, but may not be available. There is also signage marking the taxiways.