• Title/Summary/Keyword: Large airplane

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Air Pollution by Airplane Engines (항공기 엔진에 의한 대기오염)

  • 김대식
    • Journal of the Korean Professional Engineers Association
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    • v.32 no.5
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    • pp.118-125
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    • 1999
  • Air pollutant emissions from airplane engines are estimated about 2 to 4 % of mobile source of USA and European countries which is not a large portion of current air pollution. But the passengers and airfreights are continuously increasing 5 to 7% annually and potential demands of air transportation services come to present, it could effect air pollutant emissions of USA will increase within 15 years. In case of our country, there has been continuous increase of air transportation service due to considerable economic growth in recent years and increase of air pollutant emissions of major international airports has followed. Rapid increase of air transportation due to launching of Inchon International Airport could effect air pollution dominantly. By this circumstance environmental specialist as well as mass communication raised necessity of air pollutant emission regulation from airplane engines. It is estimated that air pollutant emissions from airplane engines in our country is 2.7% of automobile sources, 10,809 ton, which is the same level as USA and European countries. It is increased by 12,2% compared to air pollutant emissions during 1996 and it will be increased more than a half of current air pollutant emission within 15 years due to our country's economic condition. Therefore implementation of airplane engine emissions regulation as well as test standards and accumulation of technology about characteristics of airplane engine emission and reduction method are needed. And continuous estimation of air pollutant emission from airplane engines and monitoring of increment as well as development of countermeasures by long term are necessary.

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Transient Responses of an Airplane Taking off from and Landing on a Very Large Floating Structure in Regular Waves (규칙파중 항공기 이.착륙시 초대형 부유식 해양구조물의 천이 응답 해석)

  • 신현경;이호영;임춘규;강점문;윤명철
    • Journal of Ocean Engineering and Technology
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    • v.15 no.1
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    • pp.26-30
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    • 2001
  • Up to now, Most studies of hydroelasticity are about frequency domain analysis. Those aren't suited for analysis of the landing take-off, and dropping of aircraft on a structure. So, the concern of this paper is the transient behavior of a VLFS subjected to dynamic load, induced by airplane landing and take-off. To predict the added mass, damping coefficient, and wave exciting force, the source-dipole distribution method was used in the frequency domain. The responses are accomplished by using the FEM scheme. A time domain analysis method is based on the Newmark β method to pursue the time step procedure, taking advantage of memory effect function for hydrodynamic effects.

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Determination of taxiing resistances for transport category airplane tractive propulsion

  • Daidzic, Nihad E.
    • Advances in aircraft and spacecraft science
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    • v.4 no.6
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    • pp.651-677
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    • 2017
  • For the past ten years' efforts have been made to introduce environmentally-friendly "green" electric-taxi and maneuvering airplane systems. The stated purpose of e-taxi systems is to reduce the taxiing fuel expenses, expedite pushback procedures, reduce gate congestion, reduce ground crew involvement, and reduce noise and air pollution levels at large airports. Airplane-based autonomous traction electric motors receive power from airplane's APU(s) possibly supplemented by onboard batteries. Using additional battery energy storages ads significant inert weight. Systems utilizing nose-gear traction alone are often traction-limited posing serious dispatch problems that could disrupt airport operations. Existing APU capacities are insufficient to deliver power for tractive taxiing while also providing for power off-takes. In order to perform comparative and objective analysis of taxi tractive requirements a "standard" taxiing cycle has been proposed. An analysis of reasonably expected tractive resistances has to account for steepest taxiway and runway slopes, taxiing into strong headwind, minimum required coasting speeds, and minimum acceptable acceleration requirements due to runway incursions issues. A mathematical model of tractive resistances was developed and was tested using six different production airplanes all at the maximum taxi/ramp weights. The model estimates the tractive force, energy, average and peak power requirements. It has been estimated that required maximum net tractive force should be 10% to 15% of the taxi weight for safe and expeditious airport movements. Hence, airplanes can be dispatched to move independently if the operational tractive taxi coefficient is 0.1 or higher.

Transient Responses of an Airplane Taking off from and Landing Very Large Floating Stricture in Waves (항공기 이 .착륙 시 초대형 부유식 해양구조물의 시간 영역 응답 해석)

  • 신현경;이호영;임춘규;강점문;윤명철
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2000.10a
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    • pp.63-67
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    • 2000
  • Up to this day, Most studies of hydroelasticity are inclined to frequency domain atnlysis. Thos amlysis Q the landing, take-4, and dropping of airaqft on a structure. So, the concern of this prrper is a tra a VLFS subjected to dymmic lazd induced by airplane larndirrg and take-off. To predict added mass, dampr exciting force, the source-dipole distribution method were used The responses are accomplished by Fdoimain analysis method is based on Newmark $\beta$ method to pursuit time step pnzcedure taking advantage function for hvdrodvnumic effects.

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Height perception of large airplane pilots during landing flare (대형 비행기 조종사의 착륙 조작 시의 높이지각)

  • Kim, Yong-Seok;Sohn, Young-Woo;Park, Soo-Ae;Kim, Chil-Young
    • Science of Emotion and Sensibility
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    • v.10 no.4
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    • pp.539-554
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    • 2007
  • Pilots of large airplanes have to land their airplanes with insufficient visual information because of high approach speed, high vertical velocity and high location or altitude of the cockpits from the runway intending to touch down. This study verifies that, due to the insufficient information, large airplane pilots can't exactly perceive height of their airplanes during the flare. Study 1 explored whether it's possible for the pilots to accurately perceive height with the static visual cues only. We showed them pictures of the runway taken from the pilot's pionts of view and asked them to assess the height of the airplanes. They determined exact height of the airplanes at the height of 85 feet, but they could not, at lower than 55 feet which is the flare preparation altitude. Study 2 explored whether it's possible for the pilots to accurately perceive height when dynamic cues were added to the static visual cues. We showed them videos of the runway taken from the pilot's pionts of view. With more cues they determined exact height of the airplanes at the height of 50 feet, but they could not, at the altitude of lower than 30 feet which is the flare altitude. As experience is believed to be a major factor which affects interpretation of the visual cues, we compared the accuracy of the assessment of the experienced captions and that of the in-experienced first officers. We found there was no significant difference between them.

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Integrated Navigation System with Low-cost GPS and INS (저가형 GPS와 INS를 이용한 복합항법 시스템 개발)

  • Kim, Min-Ho;Song, Hyun-Min;Kim, Jeong-Rae
    • Journal of Aerospace System Engineering
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    • v.4 no.3
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    • pp.17-23
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    • 2010
  • GPS sensors provide accurate position and velocity of moving vehicles. However, GPS is weak at intermittent signal loss and large position error. Combination with INS improves the GPS position accuracy during the GPS signal loss. In this paper, a fusion filter using GPS and INS is developed and its perfomance is analyzed with RC car and RC airplane experiments.

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Trial Design of a Very Large Floating Airport (General Arrangement and Decision of Depth) (초대형 부유식 해상공항의 시설계 (일반배치와 깊이 결정))

  • 신현경;임춘규;정재희
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2001.10a
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    • pp.45-49
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    • 2001
  • The length and the breadth or a very large floating airport are determined by airplane types and airport facilities. However, the depth affect not only the structural strength but also the functional requirement such as a possibility of taking off and landing. The optimization problem for determining the depth is to select a design so that the cost is minimized. In this paper, a general arrangement and a method to decide the depth are proposed. Strength, functional requirement, and possibility of occurrence of deck wetness and slamming are considered in order to determine the depth of structure. Hydrodynamic forces of the diffraction and radiatin problems are predicted by applying the source-dipole distribution method, and the structural responses are obtained by the finite element method.

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A Realtime Report Generation Model using Mterialized View Management Technique Based on Database Trigger (트리거 기반의 형성뷰 관리기법을 이용한 실시간 보고서 생성 모델)

  • Choi Mi Ran;Jeon Keun Hwan;Hyun Deuk-chang;Shin Ye Ho
    • 한국컴퓨터산업교육학회:학술대회논문집
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    • 2003.11a
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    • pp.33-38
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    • 2003
  • Reports have a significant meaning in time-constrained large transaction environments, such as airplane control systems or wargame simulations. This is due to the necessity of generating reports within a limited scope of time without restraining the operation performance of large transaction environments. In order to generate reports in large transaction environments while satisfying time - constrained requirements, this paper propose a model which combines the incremental operation mechanism and materialized view mechanism using triggers and stored procedures. Further, the implementation and evaluation of the preposed model provides analysis for model characteristics.

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Incremental Materialized View Management Model for Realtime Report Generation on Large Transaction Processing Environment (대규모 트랜잭션 환경에서의 실시간 보고서 생성을 위한 점진적 형성뷰 관리모델)

  • Kim, Jin-Soo;Shin, Ye-Ho;Ryu, Keun-Ho
    • The KIPS Transactions:PartD
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    • v.11D no.3
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    • pp.533-544
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    • 2004
  • Reports have a significant meaning in time-constrained large transaction environments, such as airplane control systems or wargame simulations. This is due to the necessity of generating reports within a given time limit without restraining the operation performance of large transaction environments. In order to generate reports in large transaction environments while satisfying time-constrained requirements, this paper proposes a model which combines the incremental operation mechanism and materialized view mechanism using triggers and stored procedures. Further, the implementation and evaluation of the proposed model provides the Identification of the characteristics of the proposed model.