• Journal of Aerospace System Engineering
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• v.14 no.6
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• pp.10-17
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• 2020

The Korean medical evacuation helicopter was developed based on the Korean Utility Helicopter (hereafter referred to as 'Surion'). It uses an auxiliary power unit and engine for heating during winter operation. The helicopter maintains the internal temperature of the aircraft using its bleed air to satisfy its operational capability. However, due to the air inflow through the gap between the aircraft skin and door, additional heating for operating the portable medical equipment and preventing hypothermia in evacuated patients is required. Accordingly, an electric auxiliary heater was developed for additional heating during winter operation, and environmental, durability, and performance tests were conducted per MIL-STD-810G and MIL-STD-461F. The auxiliary heater was verified per the tailored airworthiness certification criteria.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.5
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• pp.344-357
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• 2019

Operational failures may occur even though there had been no signs of defect during the manufacturing process, which may be caused due to exposure to environmental stress which had not been addressed properly during the design process. It is thus necessary to perform environmental testing to determine the cause of the failures. Environmental testing is also used to determine whether a materiel has enough tolerance to the environmental stress during its operation. In this study, the method and level for each environmental testing are properly tailored and applied to a fight aircraft intended to operate in ROK (Republic of Korea), based on the MIL-STD-810G Change 1. Since each part of a fighter aircraft may be exposed to each different environment, LRUs (Line Replaceable Units) exposed to similar environment should be tested similarly. In addition, the decision whether to apply specific test and the tailoring technique in test level were derived for natural and induced environments, respectively. As a fight aircraft is assumed to operate in ROK, the tailoring of test methods and test level to fit to the environment in Korean peninsula is necessary. Further research is needed in determining a specific procedure and a specific level in a test method, and also in determining the test sequence, when conducting more than one is needed, because it can alter test results and it hence becomes an essential element in test design.

• Journal of Applied Reliability
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• v.5 no.2
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• pp.209-219
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• 2005

The required standards for environmental tests for communication and electronic equipment used currently are not standards into which the Korean climate and use environment are taken into consideration. But the most used environmental testing standards of the U.S. army(MIL-STD-810) has been used without taking into consideration the Korean domestic situation and conditions by simply translating the US standards. Adherence to these standards may increase in the manufacturing costs according to excessively strict standards. Therefore, this paper will propose a new environmental test standards for temperature.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.4
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• pp.415-422
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• 2016

When shock acceleration is applied to a mechanical system, it may cause malfunctioning and damage to the system. Hence, to prevent these problems when developing a gimbal structure system for observation reconnaissance, the MIL-STD-810G shock standard must be satisfied as a design specification. Rubber vibration isolators are generally assembled on the base of the system in order to reduce the shock transferred from the aircraft. It is difficult to analyze the transient behavior of the system accurately, because rubber has a nonlinear load-deformation curve. To treat the nonlinear characteristic of the rubber, bilinear approximation was introduced. Using this assumption, transient responses of the system under base shock acceleration were calculated by the finite element method. In addition, experiments with a true prototype were performed using the same conditions as the analytical model. Compared with experimental data, the proposed numerical method is useful for the transient analysis of gimbal structure systems, including rubber vibration isolators with nonlinear stiffness and damping.

• Journal of the Korea Society for Simulation
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• v.27 no.2
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• pp.25-33
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• 2018

When developing military equipment, it should be designed considering the temperature condition so that the operator can operate in a stable environment. The shelter for storing various military equipments is operated in various environments. The storage temperature and operating requirements of the test equipment and repair accessories shall be $-32^{\circ}C$ to $50^{\circ}C$ and the inside of the shelter shall be designed to meet the storage temperature and operating requirements. In this study, thermal analysis of a 2.5 ton military shelter operating under high temperature and solar heat conditions is performed considering MIL-STD-810G. The thermal analysis was applied by using the concept of heat resistance and heat circuit, and the solar thermal test was performed on the actually manufactured military shelter in order to verify the analysis results.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.44 no.9
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• pp.769-774
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• 2016

Epoxy polymer exposed to solar radiation on long-term is required to a long-term environmental test in order to ensure the reliability of operation performance. In this paper, the solar aging experiment is performed for 7, 14, 28, 56, and 84 cycles, using solar simulator designed according to MIL-STD-810. After the aging experiment, measuring RGB values and using the CIE1976 color space, each RGB decreasing rates and total color shift are calculated. In addition, using a universal testing machine, mechnical properties according to ASTM-D638 are measured. As a result, by increasing solar aging period, total color shift is increased, and the tensile strength and elongation are decreased, but the elastic modulus and the poisson's ratio are slightly changed.

• Journal of Aerospace System Engineering
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• v.9 no.2
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• pp.51-56
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• 2015

In the vibration test, Most of the test specifications is standardized methods of sinusoidal excitation. However, in accordance with the ability of the test equipment progress and developments of electronic technology, methods of random vibration test is standardized in the MIL standard. Therefore, in this study, we tried to analyze Missile Guidance Structure using a finite element analysis with ABAQUS 6.13 that is commercial program. First, Random response analysis is analyzed. Following analyzing the results, we wanted to find the model that is lightweight and resonance does not occur.

• Journal of computational fluids engineering
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• v.13 no.4
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• pp.24-32
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• 2008

Environmental test is divided into operation test and storage test. The temperature of storage test is induced temperature which is considered with all sort of the heat source. Induced temperature is the temperature to be adapted to each item and platform and can be induced by computer simulation, laboratory, and real field test. We considered the induced temperature to be associated with solar heat source. In this research. First, we compared the induced temperature which be occurred by one experiment for thin plate in solar test chamber with the other one which be occurred by computer simulation to be SolidWorks 2007 COSMOS FloWorks. After this verification, we showed induced temperature which can be occurred when the test item is stored. Especially, we bring out the induced temperature by applying the ambient temperatures which is presented by MIL-STD-810F and brought out in preceding research.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.10a
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• pp.519-520
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• 2010

R-410A 냉매를 적용한 9,000 Btu 군용에어컨은 2 1/2톤 쉘터카고 차량에 탑재된 쉘터를 냉, 난방하기 위해 사용된다. 이 에어컨은 차량에 탑재된 쉘터의 벽면에 설치되기 때문에 차량 이동 중의 진동, 충격 환경에서 그 기능이 유지되어야 하며, 이에 대한 진동시험을 실시한다. 진동시험은 MIL-STD-810G, 514.5C-VII Composite Wheeled Vehicle 규격에 따라 수행하며, 동특성시험을 통해 확보된 입력 진동값을 진동 규격과 비교하여 적합성을 판단한다.

• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.2
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• pp.70-83
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• 2001

The required standards for environmental tests for communication and electronic equipment used currently in the army are not standards into which the Korean climate and use environment are taken into consideration. But the environmental testing standards of the U.S. army at the time of its establishment(MIL-STD-810) “A” version has been used without taking into consideration the Korean domestic situation and conditions by simply translating the US standards. Adherence to these standards may limit the ability to supply materials in case of emergency since the increase in the manufacturing costs according to excessively strict standards induces an increase in the acquisition cost of military equipment, unnecessarily high maintenance and repair expenses are consumed, and stocks of parts for the military use have to be retained at all times.