09-01-02-Concept of disembarkation.pptx

Aerospace Assemblies

Assembly concept

Misalignment concept

Introduction

The head override values will depend on the type of fixing and the aircraft zone where the fixing will be installed. This is called head misalignment. These values can be found in the working documents or in chapter 51 of the SRM in maintenance. Never negative for rivets.

Conception YA Group For LAUAK SCHOOL – All rights reserved.

Introduction

In the example opposite (B737), the overruns that are within limits will be smaller in the shaded areas called aerodynamic zones.

Conception YA Group For LAUAK SCHOOL – All rights reserved.

Misalignment measurement

The misalignment of the countersunk screw heads is an important factor and contributes to the aerodynamic profile of the device.

Measurements should be taken accurately at the points shown in the figures below.

Conception YA Group For LAUAK SCHOOL – All rights reserved.

Misalignment measurement

To perform these measurements, use a comparator mounted on a tripod or quadripod (depending on the surface type), or possibly by comparison with the finger using a set of shims.

Tripod comparator

Conception YA Group For LAUAK SCHOOL – All rights reserved.

Mismatch measurement

In case the overrun is too large, remove the fastener and redo the milling.

Otherwise, or if the milling is too deep, check with the requested values. Only the structural rivets should have a positive mismatch. Other fastenings sometimes have negative values.

Conception YA Group For LAUAK SCHOOL – All rights reserved.

Question

Conception YA Group For LAUAK SCHOOL – All rights reserved.

Summary

YA Group Design For LAUAK SCHOOL – All rights reserved.

Objectives

At the end of this course, you will be able to :

YA Group Design For LAUAK SCHOOL – All rights reserved.

Evolutions

YA Group Design For LAUAK SCHOOL – All rights reserved.