---
title: "AMC E 620 Performance: Formulae — CS-E · Avioverse"
description: "The following corrections from the observed test conditions to the assumed atmospheric conditions of pressure and temperature should be used within the…"
url: "https://avioverse.aero/regulations/easa/cs-e/subpart-e/amc-e-620-performance-formulae"
---

# AMC E 620 Performance: Formulae

Engines (CS-E) · CS-E · EAR revision 7 Dec 2023

AMC Acceptable means of compliance

## AMC E 620 Performance: Formulae

(1) The following corrections from the observed test conditions to the assumed atmospheric conditions of pressure and temperature should be used within the range of conditions appropriate to the particular type of Engine, i.e. taking into account the characteristics of the Engine Control System, and the possible effect of Reynolds Number, unless more accurate or additional corrections for a particular type of Engine have been agreed or required by the Agency.

Gas Pressures

S.I. Units

Gas Temperatures

Rotational Speed

Thrust

S.I. Units

Mass Air Flow

S.I. Units

In cases where certain proprietary types of air flowmeter are employed, it should be noted that Wo is the actual air consumption of the Engine during test.

Fuel Flow

S.I. Units

Power

S.I. Units

(2) Notation

| B | = | Barometric pressure in test chamber                                                     | hPa  |
| - | - | --------------------------------------------------------------------------------------- | ---- |
| θ | = | Observed intake temperature, corrected for instrument temperature and scale errors only | K    |
| P | = | Pressure                                                                                | hPa  |
| T | = | Temperature                                                                             | K    |
| N | = | Rotational speed                                                                        | rpm  |
| F | = | Thrust                                                                                  | kN   |
| W | = | Mass air flow                                                                           | kg/s |
| w | = | Fuel flow                                                                               | kg/h |
| P | = | Power                                                                                   | kW   |

(3) Suffixes

Suffix ‘o’ denotes an observed result, corrected for instrument temperature and scale errors only. Suffix ‘c’ denotes a result corrected to the standard atmospheric pressure and temperature conditions of CS-E 620.

\[Amdt. No.: E/1]

AMC — CS-E · ED Decision 2007/015/R · CS-E Easy Access Rules · EAR revision 7 Dec 2023

[All rules in SUBPART E – TURBINE ENGINES: TYPE SUBSTANTIATION](https://avioverse.aero/regulations/easa/cs-e/subpart-e)

Consolidated from the EASA Easy Access Rules (revision 7 Dec 2023, extracted 13 Oct 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.