Page 17 - 2018-Issue1

VOLCANIC ERUPTIONS & AVIATION 17

Captain Klaus Sievers began flying commercial aircraft for
Lufthansa in 1979. From 1995 to 2016 he was a Captain on Boeing
747. During his career, Klaus developed a deep respect for Mother
Nature, and through practical experience and self-directed study,
he has gained a profound understanding of aviation weather in
all its forms, including space weather. Captain Sievers is in charge
of the special interest group on Weather at Vereinigung Cockpit
(German Airline Pilots’ Association). He was the principal author
of the ECA paper Pilots’ Vision on Weather, represents IFALPA on
the ICAO MET Panel.

2. Volcanic Contamination - Basic Considerations Charted information on volcanic ash and SO2-clouds should
Global standards for acceptable levels and amounts of ash and show airspace with defined amounts of ash or SO2. The system
volcanic SO2 aerosol that humans in aircraft, aircraft, and aircraft should indicate at least three levels of ash or SO2 contamination,
systems such as engines, windshields, electronics, and air supply e.g. no relevant, low and high amounts of ash. Satellite pictures
units can safely accept do not exist today. Aircraft manufacturers containing ash and SO2 indications should be provided for every
and aircraft system builders are known to be working on this flight in areas affected by volcanic clouds, and these pictures should
subject in-house. We think that it may be time to consider show the planned flight track for easy reference.
development of standards acceptable to certification agencies like Recent volcanic colour code information, satellite pictures,
the FAA or EASA. This should extend to the aerosol/gas retrievals, and analysis of ash and SO2 clouds, indicating the
components of volcanic clouds, too, which consist primarily of SO2 presence of discernible ash and SO2 shall be part of the briefing
and its reaction products like sulfuric acid. package, and should be updated as required during flight. As
Aircraft should be equipped with sensors that indicate the modelling of ash and SO2-clouds evolves, 3-d predictions of
presence and amount of volcanic ash and SO2-clouds both in the hazards and their evolution over time needs to be published. Thus
air surrounding the aircraft and sufficiently far ahead of it to enable evolved, 4-d volcanic ash information to support 4-d trajectories
pilots to take appropriate action, much like we have weather radar should then be generated and published.
for water-type clouds. Visual identification by pilots should not be The volcanic ash and SO2-cloud information used should be
the main means to determine the extent of volcanic clouds for continuously validated and updated using ground, airborne, and
safety of flight and ATM purposes. After all, flight of an aircraft is satellite measurements. The boundaries shown on published charts
governed by reference to instruments; instruments for height, should accurately depict the boundary between charted values. If
airspeed, temperature, and more. The same should apply to this is not achievable, it should be clearly indicated on the charts,
volcanic clouds (ash, gas, aerosols). If a system is used that is based and areas should be enlarged to show the most conservative value.
on some total permissible amounts of ingested ash over a certain It is understood that in-flight updates to this information
span of time, a certain dose of ash, the current received dose should should be uplinked to aircraft as they become available.
be indicated to pilots.
Pilots need to be given training in volcanic cloud recognition, 4. Further Considerations
flight planning with regards to volcanic clouds, and operation of Beyond what has been considered so far, enhanced resilience to
aircraft when operating in a volcanic cloud. This should include volcanic eruptions can be achieved by the following considerations:
in-depth instruction on the airlines´ specific Safety Risk • Information on hypothetical eruptions should be published for
Assessment, which should be easily accessible to pilots. Regular planning purposes
practice of unexpected volcanic ash encounters in the simulator
helps to prepare pilots for multiple system failures to be expected • Dissimilar redundancy should be introduced in eruption
in a severe encounter. alerting
• Information about ash and forecasts for ash clouds should be
3. Volcanic Contamination Information for Flights published in modern electronic formats, like KML and
Information on volcanic ash and SO2-clouds for pilots shall be WXXM 2.0
displayed on charts or electronic systems in standardized, • A website powered by all VAACs should show all ash and
easy-to-understand, graphical form, using colour to highlight SO2-cloud related information, including valid advisories.
important aspects of ash reports and forecasts.

InterPilot | The Safety and Technical Journal of IFALPA ISSUE 1 | 2018