Agency Calls For Advisory System, Automated IPS Activation
The Federal Aviation Administration is seeking comments on a
proposed rule calling for installation of systems on
transport-category aircraft, to alert flight crews to conditions
favoring the accumulation of airframe icing, and thus requiring
pilots to activate anti-icing systems.
The FAA says such systems would remove any question of
when pilots are required to activate such measures... which could
reduce the number of icing accidents.
In its Notice of Proposed Rulemaking, available for download at
the FMI link below, the FAA states its proposed standards would
require a means to ensure timely activation of the airframe ice
protection system on aircraft certified for flight into known icing
(FIKI) conditions. The FAA proposes a warning system that would
alert crews to low temperatures and the presence of moisture --
conditions that could lead to airframe icing -- and standards
calling for the mandatory activation of deicing systems at that
time.
Transport category aircraft currently offer several measures
intended to assist pilots in determining if deicing equipment
should be activated -- including outside air temperature gauges,
and on many aircraft, ice lights that shine on a wing's leading
edge to show the pilot the level of ice accretion. Those systems
still rely on the pilots' discretion on proper deicing procedures
from that point, however.
The FAA states such ice warning systems could conceivably
activate an aircraft's ice protection system automatically... thus
removing the pilot from the decision-making process. The FAA cites
several icing accidents in which pilots either failed to notice
icing accretion -- or did note such conditions, but then failed to
activate the proper deicing systems -- as justification for the
need to automate the process.
The big question in such a plan is one of cost -- to both
aircraft manufacturers, and operators. The FAA estimates the cost
of implementing an automated IPS system on a particular type or
group of aircraft at $485,000; the cost to install such a system is
estimated to be close to $15,000... per plane.
By comparison, the cost to design an advisory system -- which
would still require pilot activation -- would be slightly less for
manufacturers, at $447,500. Such a system would cost significantly
less per plane at the operator level, however, at an estimated
$7,250 per aircraft.
The FAA will accept comments on the NPRM before July 25,
2007.