该SAE航空航天标准(AS)提供了一种使用Fortran通用块编写燃气涡轮发动机性能计算机程序的方法。如果要使用“函数调用应用程序接口”（API），则建议使用ARP4868和ARP5571作为本文档中描述的替代方案。 当程序用户和供应商同意某个特定程序应以Fortran格式提供时，本文件应与AS681一起用于稳态和瞬态程序。 本文还描述了如何利用Fortran字符存储来扩展调用程序和引擎子程序之间的信息接口。

This SAE Aerospace Standard (AS) provides a method for gas turbine engine performance computer programs to be written using Fortran COMMON blocks. If a “function-call application program interface” (API) is to be used, then ARP4868 and ARP5571 are recommended as alternatives to that described in this document. When it is agreed between the program user and supplier that a particular program shall be supplied in Fortran, this document shall be used in conjunction with AS681 for steady-state and transient programs. This document also describes how to take advantage of the Fortran CHARACTER storage to extend the information interface between the calling program and the engine subroutine.