地球温暖化により民間航空機の離陸重量に制限が出る可能性がある。
気温が上がると空気密度が下がり、航空機が飛び立つための揚力が得られにくくなる。
温室効果ガス濃度に対応した排出シナリオ
「代表的濃度パス（RCP)」
単位は放射照度（＜w/㎡＞
▲現状の空港インフラで現行機を運用するには、最大4%の搭載量削減が求められる。
▲暑さによる揚力不足で欠航が発生。
The impacts of rising temperatures on aircraft takeoff performance
https://link.springer.com/article/10.1007/s10584-017-2018-9
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http://theatlasgroup.biz/temperature-humidity-affect-aircraft-performance/ "
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The Effects of Aircraft Performance from Temperature and Humidity Affect
The design capabilities of an aircraft affect its performance. Thus, certain environmental influences and aerodynamics play an important role. It is not enough that you know the airplane maneuvers, manageable load, stall speeds, and take off speeds. You should also be aware how temperature and humidity affect aircraft performance.
Facts to Know
Here are important facts that you should know:
- The optimum performance of an aircraft is decreased when there is an increase in altitude or temperature.
- High humidity reduces available air for combustion, which leads to enriched mixture and eventually, reduced power.
An airplane’s performance capability is related to that of standard atmosphere or 29.92” of mercury at 15 degrees Celsius. However, in the actual situation, this doesn’t always happen. As temperature and altitude increases, the optimum performance of the aircraft also decreases.
In high temperature, air density decreases. For instance, during a hot sunny day, the aircraft needs more runway, faster approach, and poor climb rate. An uninformed or unsuspecting pilot can face a disastrous situation when hot and high combine. Aerodynamically speaking, high elevation and high temperature creates a situation where the performance of a plane is reduced. With reduced fuel-air mixture, the Hp output of the engine also decreases.
The power of the engine is also affected by high humidity. The reduced power is due to the enriched mixture since there is less air available and high water vapor level.
Temperature can’t be controlled and to ensure the overall optimal performance of an aircraft, certain devices are used such as turbochargers and superchargers. These devices are capable of condensing atmospheric air. The engine is able to perform optimally regardless of temperature and air density.
Since temperature and humidity affects performance, aircraft operations are usually scheduled early in the morning or late at night.
Performance at Its Best
It was mentioned earlier that warm temperature decreases performance of aircrafts. Therefore, it is safe to say that cold weather has its advantages. Warm and cold weather offers good and bad sides. Still, many pilots claim that their aircrafts are able to perform better in cold weather.
Pre-flight inspection tends to be difficult for some because it involves more prep time, and during winter, de-icing is also required. There is truth that aircraft performs better in cold weather, but you should also emphasize on the safety of passengers. The take off of aircraft is carried out efficiently during cold weather, as well as its fly. Still, there is the danger of freezing temperatures. Safety should be the primary concern of the pilot.
The reason why aircrafts show optimal performance during cold weather is because of the engine power and air density. Cold air is denser in comparison to warm air. Therefore, the performance of the engine and airlift is carried out efficiently. A larger mass of fuel/air mixture is used; therefore the internal combustion and turbine run well. The aircraft gets more power.
The propeller bites into the denser cold air. The greater air mass is thrust backwards. This leads to more power and thrust. When the plane has more power, it can quickly accelerate upon take off. You will notice that the plane has increased climb rate, reduced take-off roll, more lift (for the wings), and the plane is able to take off even when the ground speed is low.
When the engine has more power, the aircraft is able to operate optimally. With more air getting into the cylinders of the engine, more power is expected. If you are into manufacturing/fabrication of aircrafts, you should be aware of these things. Harnessing an aircrafts performance is required if you want to stay on air safely!
