Airworthiness Notices

Airworthiness Notice - B051, Edition 1 - 26 January 2000

ESSO UNIVIS J13 Hydraulic Fluid


This notice is to advise all operators and maintainers to ensure that any UNIVIS J13 hydraulic fluid they may have in stock and intended for use on aircraft meets the appropriate specification.


There are two versions of UNIVIS J13 hydraulic fluid presently in the field:

  1. ESSO UNIVIS J13, imported by Imperial Oil (discontinued) which meets MIL-H-5606A;  and
  2. ESSO UNIVIS J13, made in Canada which does not meet MIL-H-5606A.

Imperial Oil Canada Ltd. has confirmed that changes in the formulation of ESSO UNIVIS J13 hydraulic fluid manufactured in Canada resulted in the fluid no longer meeting the MIL-H-5606A specification. In particular, this formulation does not meet the low temperature viscometrics required for aviation application.

As shown in the accompanying table, there is little difference in labeling between the two products.  This has led to several operators inadvertently obtaining and using the incorrect product.  Only J13 bottles displaying the MIL specification on the label should be used in an aviation application.

Bottle Black plastic Black plastic

Front Labeling

(English portions only)
       ["ESSO" logo]             UNIVIS           J13           HYDRAULIC FLUID        ["ESSO" logo]          UNIVIS           J13        HYDRAULIC FLUID
  Back Labeling   (English portions only) ["ESSO" logo]   UNIVIS J13   HYDRAULIC FLUID Petroleum-base, low-temperature hydraulic oil.   MEETS THE REQUIREMENTS OF U.S. MIL-H-5606A AND NATO H-520.   IMPORTED BY IMPERIAL OIL TORONTO, ONTARIO   ["EXXON" logo]     UNIVIS  J13   HYDRAULIC FLUID Petroleum-base, low-temperature hydraulic oil.                                        Licensed to:                                        IMPERIAL OIL           TORONTO, ONTARIO  M5W 1K3           Made in Canada             ["EXXON" logo]

Further information on the hazards of incorrectly identifying or mixing aircraft fluids is presented in the current edition of Airworthiness Notice B048.

For more information please contact Imperial Oil Canada Ltd., Product Support.

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