Study Sets New Following Distance Limits
Following three years of exhaustive studies, the Airbus A380
Wake Vortex Steering Group has rendered its conclusions. The
Steering Group comprised representatives from the Joint Aviation
Authorities (JAA), Eurocontrol, US Federal Aviation Administration
(FAA), and Airbus.
The study demonstrated that en route the A380 is similar to the
Boeing 747. In cruise and when flying in a "holding pattern", the
A380 is considered to be identical to any other aircraft, both for
vertical and horizontal spacing between it and any following
The study has also established that there are no wake
constraints for the A380 following any other aircraft, including
On approach, the study recommends increasing the spacing
compared with the existing rules. For a "heavy" aircraft following
the A380 spacing would increase to six miles and to 8 miles for
"medium" and "small" aircraft. Current guidance requires all
aircraft to remain 10 miles behind the A380.
The good news is since A380 is unaffected by wake turbulence
from ANY aircraft currently flying -- not even another A380 -- it
can land as close as practicable to a preceding aircraft. In a
perfect ATC world, that would help compensate for the additional
spacing required by aircraft following the A380.
On departures, a "heavy" aircraft following the A380 will have
to wait two minutes, and the "medium" sized and "small" aircraft
will have to wait three minutes. But here again, the A380 can
take-off as close as possible to any preceding airliner.
Though not specifically
addressed, flight tests provided no indication of impact on
parallel runway operations for runways separated by more than 760 m
(2500 ft). This should be monitored in operational service for
Of course, all recommendations from the study are subject to
review and possible change based on any further studies. A
interesting by product of this study is a consensus among
participants of the need for a future review of the existing
aircraft categories taking into account operational experience.
The detailed scientific work for this study was conducted by
leading international experts in the field. Airbus's flight test
program totalled 180 hours. They did back-to-back comparisons of
different aircraft, cruise wake encounter tests, and took ground
and airborne measurements of wake vortexes using a laser-based
radar, or LIDAR.