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【范围】
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1.1 Form
This specification covers three types of deicing/anti-icing material, each in the form of a non-Newtonian fluid.
1.1.1 Classification
Deicing/anti-icing fluids covered by this specification are classified as follows:
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NOTE: As per 3.2.5.2, any fluid can be tested in accordance with the AS5900 high speed ramp test and/or low speed
ramp test to demonstrate acceptable aerodynamic performance. The designations in Table 1 are for fluid
classification purposes only. Consult the fluid manufacturer for complete aerodynamic test data.
1.1.2 Non-Newtonian
A fluid defined as non-Newtonian exhibits a different apparent viscosity value when tested at the same temperature, using
the same viscometer and spindle in a predetermined volume when the only variant is the rotational speed of the spindle.
Typically, the non-Newtonian fluid shear stress is not in direct proportion to its rate of flow.
1.1.3 Pseudoplastic
A fluid described as pseudoplastic shall exhibit reduced apparent viscosity values as the spindle speed is increased, and
revert to original flow behavior when the shear stress is removed. This shall be demonstrable at the temperatures listed in
3.2.3.2.
1.2 Application
This fluid may be used as follows:
a. Unheated and undiluted, or diluted for anti-icing
b. Heated and undiluted for deicing/anti-icing as a one step process
c. Diluted with water and heated for deicing/anti-icing, as a one step process
d. Diluted with water and heated as the deicing stage in a two-step process, usually when used with the unheated and
undiluted fluid as step two
CAUTION: SAE Type II, III and IV fluid, especially when used in a one step process or in the first step of a two step
process, may cause residues to collect in aerodynamically quiet areas, cavities and gaps. These residues
can affect flight safety. Refer to ARP4737.
1.2.1 Consult aircraft manufacturer’s Aircraft Operations Manual, Aircraft Maintenance Manual and service letters to
determine any restrictions relating to the use of deicing/anti-icing fluids meeting this specification for the type and
model of aircraft being treated. Refer also to ARP4737.
1.3 Precautions
1.3.1 The lowest operational use temperature (LOUT) for a SAE Type II, III, and IV fluid shall be determined for the
neat (undiluted) fluid or for each intended use dilution and is the lowest temperature at which the fluid has been
tested and certified as acceptable in accordance with the appropriate aerodynamic acceptance test (3.2.5) while
still maintaining the 7 °C (13 °F) freezing point temperature buffer (See ARP4737). The fluid manufacturers’
literature shall clearly state the LOUT for the neat fluid and intended use dilutions.
1.3.2 The deicing/anti-icing formulation may be mildly toxic and contact with human skin and eyes should be avoided.
Prolonged exposure to concentrations of vapor or windborne mists should be avoided. Consult the fluid
manufacturers’ Material Safety Data Sheet for further information.
1.3.3 Caution should be exercised in the use of glycol-water deicing/anti-icing solutions in and around
electrical/electronic circuitry with noble metal coated wiring or terminals which could make contact with the fluid.
Exothermic reactions, which may result in fire have been reported. This may occur where defectively insulated
wires, switches, or circuit breakers carrying direct current are encountered. Fluids based on glycol shall contain
an inhibitor to minimize this potential fire hazard.
1.3.4 A fluid meeting this specification is unique to each manufacturer and may be adversely affected by mixing with
other aircraft deicing/anti-icing fluids.
1.3.5 Slippery conditions may exist on the ground, or equipment following the deicing/anti-icing procedure.
1.3.6 Deicing/anti-icing fluids should be compatible with carbon brake material. Refer to ARP4737 and the airplane
manufacturer’s maintenance and service documents for further information on fluid use. An industry standard test
method for compatibility is under development.
1.4 Safety - Hazardous Materials
While the materials, methods, applications, and processes described or referenced in this specification may involve the
use of hazardous materials, this specification does not address the hazards which may be involved in such use. It is the
sole responsibility of the user to ensure familiarity with the safe and proper use of any hazardous materials and processes
and to take necessary precautionary measures to ensure the health and safety of all personnel involved.
1.5 Fluid Qualification
It is not sufficient for a SAE type II, III, or IV fluid to meet all of the requirements of AMS1428 for airlines to be able to use
it. For such a fluid to be used commercially, it must also have holdover time guidelines and be identified on a list of
qualified fluids acceptable to regulators. For information on the qualification process of an AMS1428 fluid, refer to
ARP5718.strRefField
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