An in-depth analysis of aviation route doses for the longest distance flight from Taiwan

Abstract

This study investigated effective doses received on board an aircraft for the direct flight between Taipei and Houston, which is the longest distance flight from Taiwan with a flying distance of more than 13,000 km that takes approximately 13 h outbound and approximately 16 h inbound. Instead of choosing one representative flight, all 680 flights operated in 2017 were systematically analyzed by using a self-developed flight dose calculator, with an emphasis on effects of flight route variation and great-circle approximation. The average effective dose of 340 flights from Taipei to Houston was estimated to be 54.6 ± 7.8 μSv and that of 340 flights from Houston back to Taipei was estimated to be 64.4 ± 7.8 μSv, leading to a best dose estimate of 119.0 ± 11.0 μSv for a round-trip flight. The standard deviation associated with the mean value was approximately 10%, which offered a quantification of how daily flight routes may affect the resulting doses. As an alternative approach, the great-circle approximation predicted a round-trip dose value of 128.4 μSv, approximately 8% higher than that derived from actual fight routes. In addition, dose relationships of these flight routes with parameters including flight time, altitude, geomagnetic cutoff rigidity, and solar activity were identified using correlation coefficients and scatterplots.