Cabin Seat Research Articles

Smoke and flame temperature propagation characteristics during cabin fire in Airbus A380

The Airbus A380 cabin is selected as the research object to study the smoke and temperature propagation process of upper cabin fires. The results show that during the fire, the overall spread of smoke lasted for 600 s. At z=3.6 m in the upper cabin aisle, the time required for smoke propagation in first class, business, and luxury economy cabins is 89 s, 59 s, and 83 s. At z=3.6 m in the upper cabin seats, the time required for smoke propagation in first class, business, and luxury economy cabins is 89 s, 82 s, and 106 s. The closer the cabin is to the front of the first class cabin, the higher the temperature, while the closer the business cabin is to the fire source, the higher the temperature. In the upper cabin aisle and seats, the temperature in first class, business class, and luxury economy class is higher as it gets closer to the fire source. The ranking of comprehensive danger level from low to high is luxury economy class, first class, and business class.

Freeform concentrator design for IR wireless-to-fiber link communications.

Airplanes use heavy wired harnesses to provide multimedia services to the seats. Optical wireless communications (OWC) are a natural choice to reduce the amount of weight, reduce the wiring complexity, and avoid possible spurious electromagnetic radiation that risks affecting the airplane's navigation systems. The light's dual use as lighting and optical communications functionalities allows for providing light and multimedia content through the reading lamp. Thus, an optical system using optical fibers to replace wires and a reading lamp can provide a cabin seat with lighting and onboard connectivity. However, changing shielded harnesses by optical fibers is-from an optical design point of view-a challenging task as the reading lamp must also meet the stringent requirements to link the optical wireless transmissions to the optical fiber. The difficulty up to now lies in injecting the light emitted from the passenger's device into the optical fiber using the reading lamp as the receiving antenna and light injector. Here, we describe a proof-of-concept device that experimentally allowed for establishing a link between a transmitter and a photodetector coupled to an optical fiber-end, i.e., the link consisted of an optical wireless communication and the launching of the light modulated signal into an optical fiber. Additionally, from the experimental experience, we will describe the optical design strategies permitting designing a compound freeform concentrator to allow optical free space-to-fiber links.

Research on evaluation of emergency communication vehicle cabin’s internal environment design based on q-rung orthopair fuzzy information

The design of the emergency communication vehicle is centered around the overall layout, which is characterized by the fact that the vehicle chassis is mostly purchased parts and is equipped with an insulated and insulated box, mainly used for instrument operation and equipment placement. The emergency communication vehicle cabin environment includes: cabin seats; seat cover; control cabinet, including operation keyboard, display screen, etc; The ceiling and carpet that make up the interior space of the car; Storage box for storage equipment; tool cabinet; cabin control system facilities; Fire prevention and extinguishing facilities in the cabin; various handrails, coat racks, short ladders, lighting facilities, etc. inside the car. The design of emergency communication vehicle interior environment involves multiple disciplines, and the selection of design schemes requires scientific and reasonable evaluation methods to select reasonable schemes for optimization design. The evaluation of emergency communication vehicle cabin’s internal environment design is classical multiple attribute decision making (MADM) problems. In this article, based on bidirectional projection and grey relational projection measure, we shall propose some projection models with q-rung orthopair fuzzy sets (q-ROFSs). First of all, the definition of q-ROFSs is introduced. Furthermore, some projection models with q-ROFSs are proposed based on the bidirectional projection and grey relational projection model. Based on developed weighted projection models, the MADM model is established and all computing steps are simply depicted. Finally, a numerical example for evaluation of emergency communication vehicle cabin’s internal environment design is given to illustrate this new model and some comparisons are conducted to illustrate advantages of the new built method.

Airlines Seat Pricing with Seat Upgrading

Pricing optimization is key to the airlines’ profitability. Oftentimes, the premium cabin demand falls short of the seat capacity, making economy cabin seat upgrading a common practice. The common procedure in the airline industry solves the revenue management optimization for premium cabin first and then to determine the number of seats left for lower cabin upgrading, which together with the lower cabin seat capacity, allows to solve the lower (economy) cabin optimization. In comparison, this paper develops models to combine all the cabin capacities, including economy and premium (business/first), and solve the optimization simultaneously. The models consider cases with deterministic and random demand, respectively. Numerical tests use actual production data and indicate that the proposed models outperform the current ones in practice.

Active Noise Control for Aircraft Cabin Seats

In turboprop aircraft, the low-frequency noise field created by the propellers is the major contributor to the interior vibro-acoustic field, which determines a passenger’s discomfort. This paper deals with the experimental assessment of an active noise control (ANC) system for cabin seat headrests using two loudspeakers placed on both sides of the passenger’s head to create a local zone of quiet around the passenger’s ears. To deal with time-varying disturbances, the developed ANC system utilized a two-input-two-output filtered-X LMS algorithm developed in MATLAB/Simulink and implemented on a DSPACE control board to drive the secondary speakers and cancel the unwanted low-frequency noise components. The performance of the active headrest was investigated through real-time experimentation involving sensors, actuators, and electronic devices. The test results showed that up to approximatively 20 dB of sound attenuation could be realized in the passenger’s ears over a narrowband sound field replicated under laboratory conditions. Such achievements represent an excellent starting point toward practical applications in the design of more comfortable and acoustically efficient aircraft cabin seats.

Multipath-Assisted Radio Sensing and State Detection for the Connected Aircraft Cabin.

Efficiency and reliable turnaround time are core features of modern aircraft transportation and key to its future sustainability. Given the connected aircraft cabin, the deployment of digitized and interconnected sensors, devices and passengers provides comprehensive state detection within the cabin. More specifically, passenger localization and occupancy detection can be monitored using location-aware communication systems, also known as wireless sensor networks. These multi-purpose communication systems serve a variety of capabilities, ranging from passenger convenience communication services, over crew member devices, to maintenance planning. In addition, radio-based sensing enables an efficient sensory basis for state monitoring; e.g., passive seat occupancy detection. Within the scope of the connected aircraft cabin, this article presents a multipath-assisted radio sensing (MARS) approach using the propagation information of transmitted signals, which are provided by the channel impulse response (CIR) of the wireless communication channel. By performing a geometrical mapping of the CIR, reflection sources are revealed, and the occupancy state can be derived. For this task, both probabilistic filtering and k-nearest neighbor classification are discussed. In order to evaluate the proposed methods, passenger occupancy detection and state detection for the future automation of passenger safety announcements and checks are addressed. Therefore, experimental measurements are performed using commercially available wideband communication devices, both in close to ideal conditions in an RF anechoic chamber and a cabin seat mockup. In both environments, a reliable radio sensing state detection was achieved. In conclusion, this paper provides a basis for the future integration of energy and spectrally efficient joint communication and sensing radio systems within the connected aircraft cabin.

Premium cabin capacity sharing strategies: airline RM insights

This paper explores revenue management strategies for premium cabin capacity sharing, that is, accepting additional bookings in economy fare classes when some premium cabin seats are expected to remain empty. Two heuristics are presented and tested to evaluate the impacts of premium cabin capacity sharing on airline revenues and loads. These RM strategies are tested using the Passenger Origin Destination Simulation (PODS), which replicates the interactions between airline revenue management systems and passenger choice of airline itineraries, fare types and service offerings. Based on the simulations, the methodologies proposed can generate total revenue gains of up to 1.1%. However, two caveats are identified: first, losses in the revenue captured from premium fare classes are likely to be experienced due to displacement by economy fare class passengers. Second, premium cabin capacity sharing should only be implemented in the final stages of the booking process; otherwise, the sharing heuristics can result in revenue losses for the airline.

Research on Transfer Characteristics of Engine Vibration Load to Cabin Seat

Aeroengine is one of the main vibration sources that affect the passenger comfort. The contribution of engine vibration to the vibration response of seat will provide basic data for the design of airliner vibration comfort and engine vibration isolation installation. Firstly, the dynamical model of middle fuselage compartment with double-beam wing was established. Then, based on the typical vibration load spectrum of the engine, the acceleration responses of the key nodes of the wing beam and the seat connection points were analyzed, and the main path of engine vibration transmission to seats was identified. Finally, using operational transfer path analysis (OTPA) method, the contribution of engine front and rear mount point vibration to the vertical acceleration response of the seats was compared, and the three-dimensional information of wing structure vibration transmission was explored. The results show that the fundamental frequency component of low-pressure rotor of engine vibration has the greatest impact on the seat vertical response under takeoff and cruise conditions, the contribution rate of the front mount point vibration is about 71% and 67% respectively. However, the fundamental and its 3/2 times frequency components of high-pressure rotor have relatively large impact on the seats vertical response under flight idle state, and the contribution rate of engine front mount point vibration is about 45% and 60% respectively. In addition, the engine vibration is mainly transmitted from the wing front beam to the seat vertical response. The vertical direction of the wing beam and the rotation direction around the fuselage are also the main direction of vibration transmission.

Numerical Simulation of Solar Radiation and Conjugate Heat Transfer through Cabin Seat Textile

Abstract The solar radiation and the conjugate heat transfer through the cabin seat fabric were investigated numerically with a focus on a comparative analysis of various fabric solar reflectance or reflectivity (SR) and inlet cooling air velocity. For this purpose, 3D compressible Reynolds-averaged Navier–Stokes equations with the low Reynolds number turbulence model were utilized to simulate the airflow in the cabin. The discrete ordinate radiation model was adopted to describe the solar radiation. The conjugate heat transfer between the airflow and the fabric seats was included. The airflow temperature, radiative heat flux, and radiative heat transfer through the fabrics in a fixed cross section were studied. The results demonstrate that the increase in fabric SR leads to the increase in energy reflected to the atmosphere, which will bring about a lower temperature on the seat fabric. The decrease in emissivity and the energy absorbed results in the lower heat transfer and heat radiation and leads to the improvement of the cabin thermal environment. The high-temperature gradient near the seat causes the forced air circulation and is beneficial for the improvement of the thermal comfort. However, the cooling effect is not so obvious near the cabin seats when the inflow speed is increased.

Experimental study on dynamic thermal environment of passenger compartment based on thermal evaluation indexes.

In this article, the thermal environment and the human thermal comfort of car cabin under different driving states in summer were studied experimentally. The weighted predictive mean vote model and the weighted equivalent temperature model were used for calculation and compared with the experimental values. The experimental results show that the air temperature and relative humidity distribution in cabin are affected by the space position and driving state. The temperature of the cabin seat, which is affected by solar radiation and crew, in the heating stage is slightly higher than the air temperature, while the cooling rate in the cooling stage is much lower than the air temperature. The predictive mean vote model and the equivalent temperature model are basically consistent with the actual thermal comfort of human body under the idle and driving conditions with the change of time. The prediction accuracy of the two models under the idle condition is higher than that under the driving condition, and the overall prediction accuracy of the equivalent temperature model is higher than that of the predictive mean vote model.

Indoor air formaldehyde (HCHO) pollution of urban coach cabins

Urban coach cabin is an important indoor environment for long journey, formaldehyde (HCHO) is a carcinogenic gas and damages indoor air quality of cabins. In order to control the HCHO pollution, the air samples inside cabins were analysed with a thermally desorbed gas chromatograph, and the HCHO diffusion was simulated with a methodology of computational fluid dynamics (CFD). Results show that through the experimental monitoring, the HCHO pollution level range from 33.6 to 142.3 μg/m3, decrease quickly with time, and the attenuation trendline is univariate cubic equation. Through the CFD simulation, the indoor temperature and HCHO level of cabin front and rear ends are higher than ones of other areas for the insufficient air supply and the unreasonable arrangement of air exhaust outlet. Moreover, through the CFD simulation, the HCHO level decreases with height growth of breathing zone and increasing air supply speed, and fresh air lead to diffusion of HCHO pollution from cabin seat area to the surrounding area. Through the CFD simulation, the HCHO pollution under the wind speeds of 3~5 m/s is higher than the HCHO limit level from indoor air standard of China vehicles, which shows that the HCHO emission of cabin seat has an important impact on airborne HCHO pollution inside vehicle cabins.

A Generic Approach to Analyze the Impact of a Future Aircraft Design on the Boarding Process

The turnaround process constitutes an important part of the air transportation system. Airports often represent bottlenecks in air traffic management (ATM), thus operations related to the preparation of the aircraft for the next flight leg have to be executed smoothly and in a timely manner. The ATM significantly depends on a reliable turnaround process. Future paradigm changes with respect to airplane energy sources, aircraft design or propulsion concepts will also influence the airport layout. As a consequence, operational processes associated with the turnaround will be affected. Airlines aim for efficient and timely turnaround operations that are correlated with higher profits. This case study discusses an approach to investigate a new aircraft design with respect to the implications on the turnaround. The boarding process, as part of the turnaround, serves as an example to evaluate the consequences of new design concepts. This study is part of an interdisciplinary research to investigate future energy, propulsion and designs concepts and their implications on the whole ATM system. Due to these new concepts, several processes of the turnaround will be affected. For example, new energy storage concepts will influence the fueling process on the aircraft itself or might lead to a new infrastructure at the airport. This paper aims to evaluate the applied methodology in the case of a new boarding process, due to a new aircraft design, by means of a generic example. An agent-based boarding simulation is applied to assess passenger behavior during boarding, particularly with regard to cabin layout and seat configuration. The results of the generic boarding simulation are integrated into a simplified, deterministic and generic simulation of the turnaround process. This was done to assess the proposed framework for future investigations which on the one hand address the ATM system holistically and on the other, incorporate additional or adapted processes of the turnaround.

Development of a mining machine seat model

The paper presents the process of a seat model development for mining machine operators. The lack of availability of such numerical models was the motivation for the authors as the cabin seat with the integrated seat belt is a fundamental safety equipment. The authors dismantled an original operator’s seat and then tested its major components in order to reverse engineer the shape and obtain mechanical properties of the seat. To obtain the CAD model photogrammetric methods based on 3D coordinates measurements of the objects were used. Material properties and the characteristics of the mounting were attained by tension-compression test, performed on a universal testing machine. By combining these methods, the authors elaborated a new, detailed model of the operator’s seat, which has been used in the further research in the mining operator safety.

Visual Data Mining: Analysis of Airline Service Quality Attributes

ABSTRACTThe objectives of the study are to identify the key airline quality attributes from online review posts and to examine the effect of identified airline quality attributes on eWOM communication. This study employed data-mining techniques and logistic regression on 901 passenger reviews to evaluate the service quality of passenger airlines. The major contribution was identifying the most salient topics of travelers complimenting and complaining reviews. Passengers’ comments support that service, staff, cabin seat comfort, and entertainment are among the most discussed themes in positive and negative reviews. Additionally, value, seat comfort, staff/service, and catering were found to be significant predictors of airline eWOM.

Application design of piezoelectric effect in cabin seat belt status indication

During the special operation stage of the aircraft, if the passengers did not fasten their safety belts in accordance with the requirements, it may bring unexpected injury, resulting in unnecessary losses. So if there is a corresponding system can help the crew to accurately confirm the state of the safety belts of the passengers under special circumstances, what we said before can be avoided. The seat belt status indicator system is designed based on the piezoelectric effect can help the crew to know the state of the safety belt clearly, to ensure the effectiveness of their work.

서울시 일부 지하철 전동차 객실 시트의 먼지 진드기 알레르겐 농도와 세균 내독소 농도 조사

서울시 일부 지하철 전동차 객실 시트의 먼지 진드기 알레르겐 농도와 세균 내독소 농도 조사

Meeting the needs of disabled air passengers: Factors that facilitate help from airlines and airports

With the number of impaired air passengers having increased globally, air service providers may have the potential to create a lucrative niche market. However, it is less clear what the service needs of these passengers are as well as providing facilities and services. This paper aims to explore the service needs of impaired air passengers and to identify factors affecting the facilities and services. The results of data from a sample of 180 respondents from among airline, airport and government staff are presented in this research. These results show that the top three items which travellers complained about in relation to airlines are the lack of provision of a user-friendly on-board restroom, wheelchair services and the distance between cabin seats and restroom on board. The results also show that female staff are more likely to be willing to help impaired passengers than male staff. In considering the factors comprising perceived needs, two factors, i.e. “Compensation and improvement schemes” and “Not suitable for taking a flight” appear to have significant effects. The managerial implications are also discussed.

MIMO Hybrid Control of Structural Responses for Helicopter

A MIMO hybrid model of structural response control, which combines adaptive feedforward control and feedback control, was developed and then applied in a helicopter model to eliminate the dual-frequency harmonious vibration at cabin seats. In implementation, an AOEF (Acceleration Output Extended Feedback) controller for the MIMO case was designed to add enough damping to the control path so that the convergence rate of the FXLMS algorithm could be obviously improved. The corresponding FXLMS algorithm for the control path of closed loop was developed also. The numerical results on the finite element model of a helicopter indicated that with hybrid control, responses at four rows of seats could be controlled with two actuators and the adaptive controllers got a quicker convergence rate.

A modern aerospace modeling approach for evaluation of aircraft fuselage crashworthiness

A 9 [m/s], (30-ft/s) vertical drop test of a fuselage section of a Boeing 737 aircraft was conducted at the FAA William J. Hughes Technical Center in Atlantic City, NJ. Test was performed to evaluate the structural integrity of a conformable auxiliary fuel tank mounted beneath the floor and to determine its effect on the impact response of the airframe structure. The objective of the test was to determine the interaction between a typical transport aircraft fuselage, particularly its floor structure, and a conformable auxiliary fuel tank under severe, but survivable, impact conditions. The fuel tank used in this test is representative of tanks being installed in narrow-body transport aircrafts. The 3 [m], (10-foot) airframe section from a Boeing 737-200 aircraft was dropped from a height of 4.27 [m], (14-feet) generating a vertical impact velocity of 9 [m/s], (30-ft/s). The airframe test section weight of 3,982.5 [kg], (8780-lb) simulated the load density at the maximum takeoff weight condition. The weight included cabin seats, dummy occupants, and simulated fuel in the 1,892.71 liters, (500-gallon) fuel tank. Structural response data were obtained during the impact from instrumentation installed on the fuselage structure, floor structure, and the fuel tank. The fuselage test section sustained severe damage after the test. Portions of the cabin floor were damaged due to the impact with the auxiliary fuel tank located in the cargo compartment. Portions of the fuselage bottom were crushed by approximately 66 [cm], (26-in). The bottom of the fuel tank was punctured in numerous locations causing fuel to leak out. The strength and rigidity of the fuel tank limited the inherent ability of the fuselage structure to absorb energy crushing during the impact. The test data were used to compare with a finite element simulation of the fuselage structure and to gain a better understanding of the impact physics through analytical/experimental correlation. To perform this simulation, a full-scale 3-dimensional finite element model of the fuselage section was developed using the explicit, nonlinear 3-D Finite Element code, LS-DYNA. The emphasis of the simulation was to determine the structural deformation and floor-level acceleration responses obtained from the drop test of the B737 fuselage section with the auxiliary fuel tank.

Optimal construction of airline individual crew pairings

In this paper we develop eight scheduling models to minimize crew costs and to plan the proper individual pairings using real constraints for a Taiwan airline. These models are formulated as integer linear programs, where column-generation-based algorithms are developed to solve them. A case study regarding the operation of a major Taiwan Airline is presented. Scope and purpose The construction of airline cabin crew schedules is generally separated into two problems, crew scheduling and crew rostering. Traditionally, the planned pairings from crew scheduling are not allocated to individual crew members. In reality, crew members from different home bases are considered for service on the same flight. Crew members with higher ranks may be assigned to serve lower classes of cabin seats. As well, flights having different aircraft types are sometimes combined to form a pairing. When these factors are handled in downstream crew rostering, it increases not only the complexity of the crew rostering problem but also the crew cost. The purpose of this paper is to incorporate such factors as multiple home bases, mixed aircraft types and multiple cabin classes into the crew scheduling problems, to improve the construction of cabin crew schedules, and to better link crew scheduling and crew rostering.