Wind Gradients and Turbulence

This document presents four events linked to meteorological phenomena, strong winds at altitude or convective movements associated with cumulonimbus. Although different in nature, these examples have some common points: the sudden deterioration of the conditions, late detection, sometimes inappropriate reactions, lack of information transfer within flight crews (PIREP). Since they are difficult to characterize in flight and meteorological forecasts are often inaccurate, these phenomena can be underestimated and poorly managed. Making those involved more aware, in-flight updating of information allowing for better anticipation and increased vigilance when approaching areas of risk can all help flight crews to avoid or to reduce the effects.


White sky and white ground, no shadow and no horizon set you up for CFIT

Weather Conditions Associated with Jet Engine Power Loss and Damage due to Ingestion of Ice Particles

The aviation industry has now connected a number of jet engine power-loss and damage events to the ingestion of ice particles. Ice particle icing related jet engine power-loss and damage events are occurring during flights of large transport aircraft, commuter, and business jets. These events have only recently been recognized as occurring in regions of ice particles aloft within convective clouds. The events have included engine surge, stall, flameout and rollback, as well as engine compressor damage due to ice shedding. All have been shown to have occurred during flight near convective weather mostly at high altitude.

Volcanic Ash Awareness

The aim of this Briefing is to provide information about volcanic ash effects on aircraft, and operational guidelines, in order to help preventing a volcanic ash cloud encounter.

Volcanic Ash Avoidance

A commercial aircraft encounter with volcanic Ash can threaten safety of flight because of resulting conditions that can range from windshield pitting to loss of thrust in all engines. Developments in technology and communication networks have significantly decreased the probability of such an encounter in the last several years. Despite these developments, however, a 737-700 recently flew through a volcanic ash cloud. Updated information about advancements in ensuring safe operations and minimizing damage to the airplane during a volcanic ash encounter is now available to flight crews.

Volcanic Ash Danger to Aircraft In The North Pacific

The world’s busy air traffic corridors pass over hundreds of volcanoes capable of sudden, explosive eruptions. In the United States alone, aircraft carry many thousands of passengers and millions of dollars of cargo over volcanoes each day. Volcanic ash can be a serious hazard to aviation even thousands of miles from an eruption. Airborne ash can diminish visibility, damage flight control systems, and cause jet engines to fail. USGS and other scientists with the Alaska Volcano Observatory are playing a leading role in the international effort to reduce the risk posed to aircraft by volcanic eruptions.

Turbulence Education and Training Aid

The Turbulence Education and Training Aid was developed by an industry team consisting of participants from airlines, airplane manufacturers, and the FAA to provide a means for the reduction of injuries and damage caused by turbulence encounters. The training package consists of this document and an accompanying. Turbulence is the leading cause of injury in non-fatal accidents...

Thunderstorms kill!

Thunderstorms kill. They kill with wind, rain, ice, hail, lightning, downbursts

The Risk Of Microburst

Flight Crew of a DC-10 Encounters Microburst During Unstabilized Approach, Ending in Runway Accident

The Ice Crystal Weather Threat to Engines

High-altitude ice crystals in convective weather are now recognized to be a cause of engine damage and engine power-loss

Power Loss in Ice Crystal Conditions

Ice crystals (frozen water) associated with convective clouds can form ice in the engine core, where temperatures are initially warmer than freezing. Ice shedding can cause engine power loss (surge, flameout) and damage.

National Volcanic Ash Operations Plan For Aviation

This document provides information on how the Federal Aviation Administration (FAA), as the U.S. meteorological authority with regard to the International Civil Aviation Organization (ICAO), meets its obligations to the International Airways Volcano Watch (IAVW), which is sponsored by ICAO.

Lightning Strikes

Each in-service aircraft is struck by lightning at least once per year, on average. Even if the level of energy of lightning strikes is high, their effects on an aircraft are limited.
This Airbus article explains the lightning phenomenon and why aircraft are prone to lightning strikes. It describes how aircraft are designed to limit the effects of a lightning strike and ensure that the safety of the flight is not impaired. It also recalls several safety precautions to take in flight and on the ground, and what must be done when an aircraft is struck by lightning.

Hot Weather Operations by Airbus

Airbus procedures in hot weather and sandy conditions.

Getting To Grips With Cold Weather Operations

The purpose of this document is to provide Airbus operators with an understanding of Airbus aircraft operations in cold weather conditions, and address such aspects as aircraft contamination, performance on contaminated runways, fuel freezing limitations and altimeter corrections. This brochure summarizes information contained in several Airbus Industrie documents and provides related recommendations.

Freezing Rain as an In Flight Icing Hazard

The NASA Twin Otter Icing Research Aircraft experienced a prolonged exposure to "classical" Freezing Rain that formed extensive ice formations including ridges and nodules on the wing and tail, and resulted in a substantial performance penalty. Although the case study provides only a singular FZRA event with one aircraft type, it is clear that classical FZRA can pose a significant in-flight icing hazard, and should not be ignored when considering Supercooled Large Drop issues.

Flight In severe Turbulence

A turbulence encounter is a play featuring three characters: the atmosphere, the aircraft and the pilot (whether a human pilot or an auto-pilot). The purpose of the Airbus article is to review the respective role and contribution of these three actors, through the main aspects associated with flying in severe turbulence at altitude.

Engine Power Loss in Ice Crystal Conditions

High-altitude ice crystals in convective weather are now recognized as a cause of engine damage and engine power loss that affects multiple models of commercial airplanes and engines. These events typically have occurred in conditions that appear benign to pilots, including an absence of airframe icing and only light turbulence. The engines in all events have recovered to normal thrust response quickly. Research is being conducted to further understand these events. Normal thunderstorm avoidance procedures may help pilots avoid regions of high ice crystal content.

Cosmic Radiations by Airbus

This Airbus document deals with cosmic radiations coping with myths and realities of cosmic radiation. It has published in 2003 during the 12th Performance & Operations conference in Rome.

Cosmic Radiations

Crew members who regularly fly at high cruise altitudes receive higher levels of ionizing radiation than the general population. The increased risk appears to be slight, but greater attention is being focused on monitoring of, and education about, ionizing radiation.

Cold Weather Operations by Airbus

A reminder of Impact on the Fuel System and Dispatch

Caution Lightning

Lightning is the personal signature of thunderstorm. It is beautiful,inspiring, spectacular and...lethal

Avoiding Convective Weather Linked to Ice-Crystal Icing

Understanding the weather conditions that have been linked to ice-crystal icing can help pilots avoid situations that may put airplane engines at risk for power loss and damage

A Description of Convective Weather Containing Ice Crystals Associated with Engine Power loss and Damage

This presentation is intended to enhance pilots’awareness of ice crystal icing conditions where engine events have occurred

An Overview of NASA Engine Ice-Crystal Icing Research

Ice accretions that have formed inside gas turbine engines as a result of flight in clouds of high concentrations of ice crystals in the atmosphere have recently been identified as an aviation safety hazard. NASA’s Aviation Safety Program (AvSP) has made plans to conduct research in this area to address the hazard. This paper gives an overview of NASA’s engine ice-crystal icing research project plans. Included are the rationale, approach, and details of various aspects of NASA’s research.

Wind information

Wind information is available to the flight crew from two primary sources: Air traffic control (ATC) and Aircraft systems.


Flight crew awareness and alertness are key factors in the successful application of windshear avoidance techniques and recovery techniques.