# Analysis of Traffic Organisation in the Kiss-and-Fly Zone of Krakow Airport: Eye-Tracking Study
## 2 Prior Related Works  
### Kiss-and-Fly Zone as a Research Object  
As was mentioned above, the research object of the study was the K&F zone of Krakow Airport. Here, it is necessary to repeat that, in general, there are different options used by passengers to reach airports: car, drop-off, taxi or public transport [10]. Each of these options creates a different load of an airport ground (surface) access, which together with a terminal or terminal complexes are integrated parts of the landslide area [11]. The K&F zone could be considered a special area assigned to drop off passengers at the airport (as well as pick them up) and as a variety of kiss-and-ride zone situated in airport surface access [12]; at the same time, trips associated with the usage of such zones are called K&F journeys [13]. In turn, the full definition a K&F zone (area) can be provided as follows: a complex infrastructure element, which is a part of airport ground access and situated in a certain location, where private cars/taxis are allowed to stop for a certain period of time (often up to 15 min) to pick up and drop off passengers and then leave without taking up space in the parking lot.  
Despite the fact that a number of passengers preferring the 'drop-off/pick-up' mode of transport reaches sometimes even 43% [14], as well as the fact that K&F zones are quite common [15], there are not a lot of scientific articles related to these complex infrastructure elements; most of the research works concentrate on K&F journeys themselves and their negative environmental impact. The first broad discussion concerning the negative impact of K&F trips was discussed in 2006: the research team calculated an extra distance concerning such trips, which was 36% more than in the situations if passengers park their cars; K&F zone was mentioned only briefly as an express pick-up area when discussing the possibility to introduce charges [13]. [PERSON] and co-authors in the article [16] also discussed mainly the problems like congestions and air pollution associated more with K&F journeys than K&F zones itself (they called them drop-off zones). The authors came to the conclusion that from the perspective of increasing environmental challenges, airports should find a way to reduce the share of such trips. [PERSON] and [PERSON] [17] reported that carbon from such modes as 'drop-off/pick-up' and'minicab' created greater CO\({}_{2}\) emissions and consequently a bigger cost of environmental damage; K&F zones themselves were not mentioned by the authors at all.  
Taking into account the facts that the performance and characteristics of airport ground accesses receive a lot of attention in terms of planning [18], and in turn, K&F zones are an integral part in many airports, surprisingly, the organisation and signage of such zones are not regulated, unified and standardised, which is confirmed by a large amount of varieties met all over the world [15]. On the other hand, such unclearness can provide only additional confusion and time loss, especially for passengers using cars and taxis to reach airports, although they are ready to pay more to reduce the time when reaching an airport ground access [19].  
Here, it is needed to add that research works concerning such types of infrastructure elements as a kiss-and-ride zone/area (as written above, K&F zones could be considered its variety) also do not cover issues of road users and confusing situations met by them. It should be pointed out that scientific articles related to the organisation and usage of kiss-and-ride zones focus mainly on aspects associated with their locations [20] and quantitative performance parameters (e.g., the amount and types of cars using them, the time of usage by different types of vehicles, etc.) [21].