al5

Aerospacelab

Airborne Measurements of the Charge of Precipitating Particles Related to Radar Reflectivity and Temperature within two Different Convective Clouds

Auteurs: 

A. Delannoy † (Onera), P. Gondot (Airbus)

Simultaneous ground based radar reflectivity measurements and airborne electric parameters (electrostatic field and charged particles) are presented. They are used to investigate the charging processes acting in convective cells. Within the two thunderclouds presented in this work, both signs are found on large hydrometeors. It is shown that negative particle charging exists at high levels in classical vertically developed cells.

Electrical Environment in a Storm Cloud

Auteurs: 

S. Soula (Laboratoire d’Aérologie, Université de Toulouse/CNRS)

This article gives an overview of the electrical characteristics of the thundercloud and the predominant mechanisms that are at the origin. The specific cloud that can produce lightning is described and the parameters that control its development and its organization are discussed. According to the variety of the scales of time and space associated with the mechanisms that occur within the thundercloud, it is difficult to simulate them both  experimentally and numerically. Thus, the advances in the knowledge

Overview of Lightning Hazards to Aircraft

Auteurs: 

Pierre Laroche

Since its early age, civil and military aviation had to face atmospheric
events of unexpected dangerousness. At that time, lightning was certainly
the most unrecognized and misunderstood atmospheric hazard to
aviation. How and where an aircraft is struck by lightning, what the expected
consequences for flight safety are and what damages could be anticipated,
were still open questions at the very beginning of the 1980s. Up until this