In public transport
, a request stop
or flag stop
describes a stopping point at which trains or buses stop only on an as-needed basis; that is, only if there are passengers to be picked up or dropped off. In this way, infrequently-used stopping points can be served efficiently.
In rail transport
, a request stop
, flag stop
or whistle stop
describes a station
at which trains stop only on an as-needed basis, that is, only if there are passengers to be picked up or dropped off. At request stops for which there are no passengers to be dropped off, trains need only slow in the vicinity of the platform — or, in some cases, pass it at speed — instead of coming to a complete stop at an empty platform. In this way, lightly-used stations can remain open and be serviced efficiently, rather than be closed.
The methods by which trains are notified that there are passengers waiting to be picked up at a request stop vary by station and country:
In the United Kingdom, most request stop stations require that the guard is informed by passengers wishing to stop at the station and that passengers waiting to catch the train merely make themselves clearly visible to the driver as the train approaches at a speed slow enough to stop if necessary. In some cases the station platform is observable by railway staff either near the station (e.g. in the signal box at Kidwelly railway station) or at the station itself. In these latter cases the staff may inform the driver in advance so that there is no need for the train to slow down unnecessarily when no passengers are waiting.
On some lines served by Amtrak
, flag stop stations require that passengers have an advance reservation to embark or disembark at the station. If there are no advance reservations for such a station, the train will generally pass at speed. Flag stops on Amtrak are rare as of 2008.
On two of the Alaska Railroad routes, passengers may flag trains nearly any place along the route.
The Ontario Northland Railway
's Polar Bear Express
from Cochrane to Moosonee is operated as a flag stop route.
Austria and Switzerland
, request stops sometimes feature an electronic signal
indicator that is operated by the passengers themselves. If a passenger presses this indicator, a control on the platform changes the signals for the driver to inform them that the train should stop at this station. Because these signals are well before the station, trains are able to pass at speed if no passenger is waiting.
In bus transport the term request stop
is used in two ways:
- A fixed bus stop which is only serviced if passengers request it, in a manner similar to a train request stop.
- A "Hail and ride" section of the route where passengers can request the bus be stopped at any point.
In urban areas, some bus stops are mandatory (i.e, the bus always stops there) while others are request stops. At a stop with many routes, a mandatory stop removes the confusion for passengers when multiple buses arrive within proximity.
Passengers wishing to board the bus at a request stop do so by hailing it with an extended arm as it approaches. Passengers wishing to leave the bus indicate this by using the stop bell or buzzer. Outside of urban areas where there are fewer overlapping routes, it is common for almost all bus stops to be request stops.
Request stops and mandatatory stops have different signs in London. Mandatory stops have the TfL roundel symbol in red on white while request stops have it in white on red, as well as the word "Request".
The second type of request stop is also used in the UK, although it is not very common. It is normally referred to as "Hail and Ride". Passengers signal the driver in the same way as for a fixed request stop anywhere along the route of the bus, regardless of whether there is a fixed stop.
The term request stop
is used on Canadian
bus networks to describe a stop to let off or pick up passengers that is not at a marked or designated bus stop. This is offered primarily in two different ways:
- "night request stop", where bus passengers can request the driver of an evening or night bus to drop them off or pick them up at a safe place. This is usually allowed to make users feel safer and more comfortable when using the bus.
- "flag stop", where bus passengers can request the driver to pick them up (usually by waving or "flagging" their hand at the driver, hence the term "flag stop") and drop them off at safe locations. This practice is usually applied to routes running through rural or suburban areas that would not be effectively served by the traditional practice of waiting at a designated stop.
Some bus companies may choose to adopt variations of the above two principal services. For example, in Metro Vancouver, people using TransLink at night can ask a bus driver to drop them off, but can not flag or request a bus driver to pick them up, even if they are in a safe boarding area. In Strathcona County, near Edmonton, Alberta, passengers can use a "dial-a-bus" service by dialing a dispatcher one hour in advance of their journey and telling the dispatcher their name and location. The dispatcher will then tell the next available bus to go to that location and will also tell the requesting person the next bus that will pick them up.