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SKYDROL aviation hydraulic fluids

The range

Skydrol™ aviation hydraulic fluid is the most advanced aviation hydraulic fluid supported by recognized experts in phosphate-ester fluid technology. 

The line of fire resistant hydraulic fluids includes 500B-4, LD-4, 5 and  PE-5. PE-5 was developed to meet the Type V hydraulic fluid requirements developed by Airbus, Boeing, and hydraulic fluid manufacturers.

Airlines can run a best practice hydraulic fluid operation using one or two fluids across a fleet. In some cases one fluid will provide an optimal operation for all aircraft in the fleet. In some cases aircraft might require different fluids for operational peak performance.


Product Safety

Phosphate ester-based fluids blended with performance additives. Phosphate esters are good solvents, and as such, will dissolve away some of the fatty materials of the skin. Repeated or prolonged exposure may cause drying of the skin, which if unattended, could result in complications such as dermatitis or even secondary infection from bacteria. 

Skydrol fluids have not been known to cause allergic-type skin rashes. Animal studies have shown that repeated exposure to tributylphosphate.

To avoid skin exposure, a worker should wear gloves that are impervious to  hydraulic fluids. Some manufacturers claim nitrile gloves are suitable for this purpose. Nylon latex and polyethylene "throw-aways" are also acceptable.


Industry Approvals

Approved by all airframe manufacturers specifying phosphate ester hydraulic fluids, including the following:

  • S.A.E. - AS1241
  • Boeing Seattle - BMS3-11
  • Boeing Long Beach - DMS2014
  • Lockheed - LAC C-34-1224
  • Airbus Industrie - NSA307110
  • British Aerospace - BAC M.333.B
  • Bombardier - BAMS 564-003
  • Fokker
  • Embraer
  • Westwind
  • Cessna
  • COMAC CMS-OL-103
  • Gulfstream 1159SCH302

Product Spotlight

Skydrol 500B-4 Aviation Hydraulic Fluids

Skydrol 500B-4 is the most worker friendly of the aviation phosphate esters; it is least irritating to skin and less prone to form mists which can be irritating to the respiratory tract. 500B-4 contains breakthrough antierosion additive and acid scavenger and has the longest service history among phosphate-ester products. 


Skydrol LD-4 Aviation Hydraulic Fluids

Skydrol LD-4 features low density, excellent thermal stability, valve erosion prevention, and deposit control. Its excellent thermal stability under real world conditions has given it a reputation as the gold standard among Type IV fluids.


Skydrol 5 - Aviation Hydraulic Fluids

5 has a unique formulation built on a new base stock, triisobutyl phosphate. Most other phosphate ester products use tributyl phosphate as a major ingredient. The difference gives Skydrol 5 the lightest weight of any phosphate-ester hydraulic fluid, thus saving fuel. 


Skydrol PE-5 Aviation Hydraulic Fluids

Type V, fire-resistant hydraulic fluid specifically formulated to meet the changing needs of the aviation industry. PE-5 provides the ultimate in performance efficiency. It supplies all the advantages of the longest fluid life at design conditions. Less frequent fluid replacement provides the benefit of reducing disposal volume.