Aircraft Intercom Systems E-Book

Askhat Khafizow

• Herausgeber: Askhat Khafizow
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 62

Veröffentlichungsjahr: 2021

Beschreibung

In this book are considered the principles construction of intercom systems, schemes features, controls appointment and the features using. The accent is made on the most using equipment, which is installed on the civil aviation aircrafts majority. Study guide for pilots and also to anyone who wants to become a pilot.

Leseprobe

Askhat Khafizow

Aircraft

Intercom Systems

Studyguide for pilots

2021

© Askhat Khafizow, 2021

All rights reserved.

Askhat Khafizow

Ukraine, Kropyvnytsky

[email protected]

ISBN 978-398-5948-03-1

No part of this book may be reproduced in any form or by any electronic or mechanical means, including information storage and retrieval systems, without permission in writing from the publisher, except by reviewers, who may quote brief passages in a review.

The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, expressed or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

CONTENTS

INTRODUCTION

1 AIRCRAFT INTERCOM SYSTEMS

1.1 Purpose, tasks

1.2 The structure and features of circuit solutions

2 AUDIO PANELS OF LIGHT AIRCRAFT

2.1 GARMIN GMA-340 audio panel

2.2 BENDIX KING KMA 26 audio panel

2.3 GARMIN GMA-345 audio panel

2.4 PMA7000M-S audio panel

2.5 GARMIN GMA 1347audio panel

3 BOEING/AIRBUS COMMUNICATION CONTROL PANELS

3.1 BOEING/AIRBUS Intercom features

3.2BOEING 737 Communication control panel

3.3 AIRBUS A320control panel

4 UKRAINIAN AIRCRAFT SOME INTERCOM SYSTEMS

4.1 Structure and features

List of abbreviations

References

INTRODUCTION

Intercom systems are used to transmit voice message signals.

In this book are considered the principles construction of intercom systems, schemes features, controls appointment and the features using.

The main element of the Intercom system is the audio panel or control panel, in which all controls and electronic circuits are concentrated, that providing the corresponding elements connection.

Understanding the processes that occurring in the intercom system is the basis the equipment flight operation on the competency level.

In this book, the processes are considered according to the principle “from simple to complex” - first, is considered the simplest scheme for pilot to pilot communication, then adding the new elements, and, finally, we get a real scheme of the modern control panel.

The control questions can also help you learn the material in a quality level.

The accent is made on the most using equipment, which is installed on the civil aviation aircrafts majority.

Enough detailed the equipment controls appointment and the using features are consideration.

This book can be useful for pilots, as well as anyone who wants to become a pilot.

Comments regarding this publication should be sent, in email form, to the following address: [email protected]

1 AIRCRAFT INTERCOM SYSTEMS

1.1 Purpose, tasks

In general, an intercom system should provide [1]:

a) For pilots:

- The conversations with each other, with the flight attendant, and also with the aircraft mechanic (when aircraft ground service);

- The announcements for passengers;

- The radio communication with the ATC through the on-board radio stations;

- The listening to the identification signals of the ground beacons;

- The listening to the special sound and voice messages which generating by airborne systems;

b) For the flight attendant:

- The conversations with the crew members;

- The announcements for passengers;

- The broadcast audio and video entertainment programs for passengers.

All messages which are transmitting through internal and external communication channels are recorded by the voice information recorder.

1.2 The structure and features of circuit solutions

The intercom composition and structure is depended of the aircraft`s purpose (passenger, transport), of the crew members number, of the on-board equipment composition, etc.

So, for example the passenger aircraft`s intercom should to provide, among other main things:

- The communication between the pilot and the flight attendant;

- broadcasting audio and video entertainment programs.

For the transport aircraft:

- The conversation with the cargo compartment personnel during the loading and unloading operations, etc.

Thus, the intercom system is a complex of equipment, the elements of which, in accordance with the tasks being solved, form different functional connections and the corresponding circuit solutions.

The main elements of the intercom system are: acoustic converters (headset, hand-held microphones, handsets, and speakers), amplifiers of electrical signals, switches or commutation buttons (“PTT” (Push-To-Talk)), control panels, and other elements. At the flight attendants workplaces of large passenger aircrafts can be organize the separate communication stations to transmit announcements to passengers, broadcasting audio and video entertainment programs, and also communication with the crew and flight attendants of other workplaces.

The intercom` system required element is the control panel.

The control panel is a switching device through which the pilot can be connects the headset elements to the radio stations input and output circuits, to navigation receivers output, to the intercom channels, can be perform adjusting and also other actions.

Currently, the industry produces a wide variety of control panels that are differ in composition, design, the controls purpose, etc.

In general, all control panels can be divided into audio control panels (ACP - audio control panel) installed on the light aircrafts with a small number of passenger seats and control panels for more heavier, long-haul aircrafts (BOEING, AIRBUS, etc.).

We will consider the intercoms possible structure of the construction and the scheme features in relation to the tasks being solved.

The intercom telephone communication between pilots

In the general case, the headset, commutation buttons, and amplifier are components of the intercom system (Figure 1.1).

The main elements of the pilot's headset are a microphone and headphones.

The microphone converts the acoustic vibrations which are created by the pilot's voice into an electrical signal. When the contacts of the PTT (Push-To-Talk) button are closed, the message signal is passed to the LF amplifier input and then, after in power amplification, to the copilot`s headphones and the headphones of own headset.

The headphone converts the electrical signals into sound vibrations, the result of that the pilot is listening to the message. The listening of own transmission indicates the serviceability of the communication channel. The maximum volume is depended on the amplifier output power.

Figure 1.1 - Intercom telephone communication scheme between pilots

The Figure 1.2 scheme is differed by the separation amplifiers presence (LFA pilot and LFA copilot).

Figure 1.2 – Scheme with separation amplifiers

The scheme features with separation amplifiers are:

- The possibility of separately (individual) volume control (control “VOL”);

- The possibility to reservation own amplifier (Figure 1.3). So, for example, if the pilot`s amplifier is not operation, then when the “RES” switch contacts are closed, the headphones of its headset will be connected to the copilot`s amplifier.

Figure 1.3 – Scheme of reserving amplifiers

Instead of a LFA general amplifier it is possible to use preamplifiers (LFA 1, LFA 2) (Figure 1.4).

Figure 1.4 – Scheme with preamplifiers

The advantage of such scheme is the possibility of separately adjusting volume signal that enters to intercom system. The adjustment is made by changing the sensitivity of the amplifier (using the “SENS” (Sensitivity) knobs).

In the intercom system of most light aircrafts, the PTT buttons are absent, i.e. the microphone circuit is directly connected to the preamplifier and any signal is generated at the microphone output is passed to the communication system (VOX technology - Voice Operated exchange). The obvious advantage of this method is the possibility of free communication between pilots without the necessity to pressing the “PTT” button. However, in the pilots' headphones, can be constantly hearing the background noise of the cockpit, for example, noise that is generating by engine operation. Therefore, the intercom systems manufacturers have developed appropriate methods to eliminate this drawback.