Airline industry CO₂ emissions have increased rapidly; air transportation released approximately 2.8% of global fuel-combustion-based CO₂ emissions in 2019. Focusing on Japan, this study explored the introduction of new passenger aircraft as a CO₂-reduction policy. To this end, the lifetime distribution function for passenger aircraft was specified. Lifecycle CO₂ emissions and the associated costs between 1965 and 2019 were then estimated. The results showed that single-aisle aircraft followed a Rayleigh distribution with a mean of 13.42, while twin-aisle aircraft followed a normal distribution with a mean of 19.82. The reduction potential of lifecycle CO₂ emissions is 28.2 Mt. over 55 years by extending the lifetime +11 years of single-aisle aircraft and shortening the lifetime −8 years of twin-aisle aircraft. If the average fuel intensity of aircraft inflow improves steadily, the shortened lifetime and introduction of more fuel-efficient aircraft contribute to a decrease in lifecycle CO₂ emissions. However, the cost associated with the lifecycle CO₂ emission reductions is USD 94.0 billion, and airlines need to pay USD 3.4 thousand to reduce CO₂ emissions by one unit. In sum, the introduction of new aircraft was shown to be cost-ineffective as a CO₂-reduction policy, and airlines need to switch to less costly alternatives.

航空业CO ₂排放量迅速增加；2019 年，航空运输释放了约 2.8% 的全球基于燃料燃烧的 CO ₂排放量。本研究以日本为重点，探讨了引入新型客机作为 CO ₂减排政策。为此，规定了客机的寿命分布函数。然后估算了 1965 年至 2019 年间的生命周期 CO ₂排放量和相关成本。结果表明，单通道飞机服从瑞利分布，平均值为 13.42，而双通道飞机服从正态分布，平均值为 19.82。生命周期 CO ₂的减排潜力排放量为 28.2 公吨。通过延长单通道飞机的寿命 +11 年和缩短双通道飞机的寿命 -8 年，超过 55 年。如果飞机流入的平均燃料强度稳步提高，寿命缩短和燃油效率更高的飞机的引入有助于减少生命周期的 CO ₂排放。但是，生命周期CO ₂减排相关的成本为940亿美元，航空公司需要支付3400美元才能减少一个单位的CO ₂排放。总而言之，作为一项减少 CO _{2 的}政策，引入新飞机的成本效益很低，航空公司需要改用成本较低的替代方案。