Exxon HyJet V  

ExxonMobil Aviation, United States

Fire-Resistant Phosphate Ester Aviation Hydraulic Fluid

Product Description

Exxon HyJet V is a Type V fire-resistant phosphate ester hydraulic fluid, which is superior in thermal and hydrolytic stability to commercially available Type IV hydraulic fluids. Better stability means the extent of fluid degradation in aircraft systems will be less than Type IV fluids, in-service fluid life will be longer, and consequently aircraft operator maintenance costs may be lower.

HyJet V provides excellent high and low temperature flow properties (kinematic viscosities) and rust protection. HyJet V has also demonstrated an improvement over the erosion protection performance afforded by Type IV fluids.


Features and Benefits

Exxon HyJet V offers the following key features and benefits:

FeaturesAdvantages and Potential Benefits
Higher stability than Type IV fluidsLonger fluid life,
Lesser need to replace fluid due to degradation,
Reduced hydraulic system maintenance costs
Meets Boeing BMS 3-11 and SAE AS1241 Type IV and Type V requirementsImproved flammability characteristics over meeting just the Type V requirements
Low densityReduced weight of the hydraulic fluid carried by aircraft,
Reduced aircraft fuel consumption,
Lower operating costs
Excellent rust protectionReduced risk of equipment damage in the event of major water contamination
Excellent low and high temperature viscosity balancePrecise hydraulic system control and response even during extended range/polar flights,
Longer aircraft hydraulic system equipment life
Excellent deposit controlLonger aircraft hydraulic system equipment life,
Reduced maintenance costs
Improved protection against electro-chemical corrosion (erosion)Protection against servo valve and pump damage
Fully compatible with all approved Type IV and Type V phosphate ester hydraulic fluidsFlexibility in use by airline operators



Exxon HyJet V is designed for use in commercial aircraft phosphate ester hydraulic systems. It meets the SAE AS1241 requirements and is included in commercial and business airframe manufacturer Qualified Products Lists, as shown below. It is compatible in all proportions with commercial Type IV and Type V phosphate ester aviation hydraulic fluids.


Specifications and Approvals

                    HyJet VMeetsIs In Qualified Products List
SAE Aerospace Standard AS1241 Type V     X           Not Applicable
Airbus NSA 307110N Type V    X                    X
Boeing BMS 3-11P Type V, Grade A and Grade C    X                    X
Boeing-Long Beach DMS 2014H Type 5     X                     X
ATR NSA307110N Type V     X                     X
Gulfstream 1159SCH302J Type V     X                     X


Typical Properties

 Test MethodHyJet V (1)Limits
Kinematic Viscosity, cStASTM D 445  
at -53.9ºC (-65ºF) 13502000 max
at -26.1ºC (-15ºF) 132135 max
at 37.8ºC (100ºF) 10.610.0 - 11.0
at 98.9ºC (210ºF) 3.63.35 - 3.75
at 127.6ºC (260ºF) 2.61.5 min
Viscosity IndexASTM D 2270280 
Shear Stability, % Viscosity Drop at 40ºCASTM D 562121 
Pour Point, ºC (ºF)ASTM D 97‹-62 (-80)-62 (-80) max
Specific Gravity at 25ºC/25ºC (77ºF/77ºF) ASTM D 40520.9970.991 -1.003
Density at 15.6ºC (60ºF), g/mL (lb/gal) ASTM D 40521.000 (8.35) 
Acid Number, mg KOH/gASTM D 9740.040.1 max
Water, Karl Fischer, mass %ASTM D 63040.090.2 max
Flash Point, ºC (ºF) ASTM D 92174 (346)160 (320) min
Fire Point, ºC (ºF)ASTM D 92186 (366)177 (350) min
Autoignition Point, ºC (ºF)ASTM D 2155›427 (800)400 (752) min
Foaming Tendency/Stability, mL foam/sec to collapseASTM D 892  
Sequence I 32/18250/100 max
Sequence II 23/13150/50 max
Sequence III 34/19450/250 max
Particle Count, NAS 1638 ClassAuto Counter47 max
Chemical Elements, ppm   
Calcium 420 max
Potassium 3848 max
Chlorine 1050 max
Sodium 115 max
Sulfur 51200 max
Four-Ball Wear, Scar diameter at 75ºC/600rpm/1hour, mmModified ASTM D 4172   
4 kg  0.210.45 max 
10 kg  0.260.50 max 
40 kg  0.630.55 – 0.85 
Electrical Conductivity at 20ºC, microSiemens/cm 0.40.3 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 at 40 ºC, cal/g/ºC (same as Btu/lb/ºF) 0.42 
(1) Values may vary within modest ranges   


Health and Safety

Based on available toxicological information, this product is not expected to produce adverse effects on health when used and handled properly. Information on use and handling, as well as health and safety information, can be found in the Material Safety Data Sheet (MSDS) which can be obtained from your local distributor or via the Internet on http://www.exxonmobil.com/lubes.

The ExxonMobil logotype, Exxon and HyJet are trademarks of Exxon Mobil Corporation, or one of its subsidiaries. PDS AV-18


Exxon Mobil Corporation
22777 Springwoods Village Parkway
Spring TX 77389

For additional technical information or to identify the nearest U.S. ExxonMobil supply source, call 1800 662-4525.

Due to continual product research and development, the information contained herein is subject to change without notification.  Typical Properties may vary slightly.