Exxon HyJet IV-Aplus is a fire-resistant phosphate ester hydraulic fluid designed for use in commercial aircraft. It is the best-performing Type IV fluid and offers to a great extent many of the performance capabilities of Type V fluids, including high temperature stability, low density, and rust protection. It is superior to all other Type IV fluids in these respects. Exxon HyJet IV-Aplus meets the specifications of all major aircraft manufacturers and SAE AS1241.
Features Advantages and Potential Benefits
Best in high temperature stability among Type IV fluids Longer fluid life
Lesser need to replace fluid due to degradation
Reduced hydraulic system maintenance costs
Lowest density Type IV fluid Reduced weight of the hydraulic fluid carried by aircraft
Effective rust protection Reduced the risk of equipment damage in the event of major water contamination
Excellent low temperature flow (viscosity) properties Precise hydraulic system control and response even during extended range/polar flights
Longer equipment life
Excellent deposit control Longer equipment life
Reduced maintenance costs
Excellent protection against electro-chemical corrosion (erosion) Protection against servo valve and pump damage
Approved by all major aircraft manufacturers Use as fleet lubricant by airline operators
Fully compatible with all approved phosphate ester hydraulic fluids Flexibility in use by airline operators
Application
Exxon HyJet IV-Aplus fire-resistant aviation hydraulic fluid is used in commercial aircraft hydraulic systems where phosphate hydraulic fluids are recommended. Exxon HyJet IV-Aplus meets or exceeds the following industry and builder specifications. It is approved against the aircraft manufacturer requirements and is included in their Qualified Products Lists.
Specifications and Approvals
SAE Aerospace Standard AS1241
Airbus NSA307110
ATR
Boeing (Heritage) BMS 3-11
Boeing (Douglas Division) DMS 2014
British Aerospace (Avro) BAC.M.333C
Bombardier/Canadair BAMS 564-003
Bombardier/DeHavilland
Cessna
Embraer
Fokker
Gulfstream Aerospace 1159SCH302D
Lockheed C-34-1224C
Typical Properties
Test Method
Results
Limits
Kinematic Viscosity, cSt
ASTM D 445
at -53.9ºC (-65ºF)
1320
2000 max
at 37.8ºC (100ºF)
10.55
10.0 -11.0
at 98.9ºC (210ºF)
3.57
3.35 - 3.75
Viscosity Index
ASTM D 2270
320
Shear Stability, % Viscosity Drop at 40ºC
ASTM D 5621
22
Pour Point, ºC (ºF)
ASTM D 97
<-62 (-80)
-62 (-80) max
Specific gravity at 25ºC/25ºC (77ºF/77ºF)
ASTM D 4052
0.996
0.993 -1.005
Density at 15.6ºC (60ºF), g/mL (lb/gal)
ASTM D 4052
1.001 (8.35)
Acid Number, mg KOH/g
ASTM D 974
0.04
0.1 max
Water, Karl Fischer, mass %
ASTM D 6304
0.1
0.2 max
Flammability
Flash Point, ºC (ºF)
ASTM D 92
174 (346)
160 (320) min
Fire Point, ºC (ºF)
ASTM D 92
185 (365)
177 (350) min
Autoignition Point, ºC (ºF)
ASTM D 2155
>427 (800)
400 (752) min
Foaming Tendency/Stability, mL foam/sec to collapse
ASTM D 892
Sequence I
0/0
100/100 max
Sequence II
0/0
75/50 max
Sequence III
0/0
100/250 max
Particle count, NAS 1638 Class
Auto Counter
4
7 max
Chemical Elements, ppm
Calcium
110
120 max
Potassium
37
48 max
Chlorine
7
50 max
Sodium
0
15 max
Sulfur
220
350 max
Electrical Conductivity at 20ºC, microSiemens/cm
1.4
0.5 min
Bulk Modulus, Isothermal secant at 100ºF/3000 psi, psi
210,000
Thermal Conductivity at 40ºC, cal/sec/cm2/ºC (Btu/hr/ft2/ºF)
33x10-5 (0.0799)
Coefficient of thermal expansion, 25 to 100ºC, per ºC (per ºF)
0.00086 (0.00048)
Specific heat capacity, cal/g/ºC (same as Btu/lb/ºF)
