Accession Number:

ADA561942

Title:

Helicopter Transmission Oil Discolouration

Descriptive Note:

Technical rept.

Corporate Author:

DEFENCE SCIENCE AND TECHNOLOGY ORGANISATION VICTORIA (AUSTRALIA) AIR VEHICLES DIV

Personal Author(s):

• Becker, Andrew
• Rawson, Paul

Report Date:

2012-02-01

Pagination or Media Count:

32.0

Abstract:

An increase in the incidence of abnormal discolouration of oil in ADF helicopter tail rotor transmissions has been observed and reported over the last eight years. Aircraft maintainers have initially attributed the discolouration to a range of contamination modes including incorrect fluid addition, hydraulic fluid contamination and degraded fluid. A program of work was conducted at DSTO to identify and characterise the cause of the abnormal discolouration. This report details the identification of a coloured metal quinizarate salt which forms in the aircraft transmissions under normal operating conditions and describes the mechanism of formation and some characteristics of the quinizarate salt to assist in developing maintenance programs to manage the coloured salt when observed in service conditions.

Descriptors:

• *DISCOLORATION
• *HELICOPTERS
• *OILS
• *TRANSMISSIONS(MECHANICAL)
• ABNORMALITIES
• AIRCRAFT MAINTENANCE
• AUSTRALIA
• CONTAMINATION
• HYDRAULIC FLUIDS
• TAIL ROTORS

Subject Categories:

• Helicopters
• Lubricants and Hydraulic Fluids
• Surface Transportation and Equipment

Distribution Statement:

APPROVED FOR PUBLIC RELEASE