Hello. Sign In
Standards Store


Revision A, December 1997

Complete Document

Aircraft Fuel System Vapor-Liquid Ratio Parameter

Includes all amendments and changes through Reaffirmation Notice , July 2014

View Abstract
Product Details
Document History

Detail Summary

Active, Most Current

Price (USD)
Single User
In Stock
Add to Cart

People Also Bought These:

SAE AS8043
ISO 9001

Product Details:

  • Revision: Revision A, December 1997
  • Published Date: July 2014
  • Status: Active, Most Current
  • Document Language: English
  • Published By: SAE International (SAE)
  • Page Count: 18
  • ANSI Approved: No
  • DoD Adopted: No

Description / Abstract:

The AIR is limited to a presentation of the historical background, the technical rationale which generated the V/L fuel condition interface requirement in specifications between the aircraft fuel delivery system and the aircraft engine fuel system, and limitations in the usage of the V/L concept.


Since the introduction, in July 1951, of the vapor-liquid (V/L) ratio fuel condition parameter as an airframe/engine interface design requirement for military applications, many questions have arisen concerning interpretation of the requirement (1, 2).1 The more important questions concern; (a) applicability of the concept to transient as well as steady state endurance demonstrations of engine fuel pump capability and, (b) limitations of the formula employed to calculate V/L ratio with respect to accuracy and range of conditions covered.

Therefore, the primary purpose of this Aerospace Information Report (AIR) is to present the background which led to the introduction of the vapor-liquid (V/L) ratio parameter defining the condition of the fuel at the airframe/engine interface and to interpret its application to specification requirements. A secondary purpose is to promote a better understanding of the subject among airframe and engine fuel system designers and users by providing a bibliography of the many, but not all, of the documents and papers published on the subject

1. Numbers in parentheses refer to the Bibliography in Appendix A.
AIA/NAS Aerospace Standards