DEPOSITED BY THE

UNITED STATES OF AMERICA

Contents

Page

PREFACE--------

INTRODUCTION ---

DEFINITIONS----

III

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XV

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Chapter 1

LOADS --

Strength and deformations...

Stiffness -----

Wing drag truss -------

Loads imparted by safety belts -

Pilot and passenger loads-

Local loads-------

Loading equilibrium.--

Flight loads ----------

Design airspeeds -----

Load factors.------

Maneuvering load factors . .

Gust load factors..

Factors -------------

Symmetrical flight conditions (flaps retracted)--

Basic flight envelopes---

Symmetrical flight conditions (flaps or auxiliary devices in operation)

High-lift devices.--.

Unsymmetrical flight conditions

Special flight conditions---

Wing load distribution.-

Balancing loads-------

Control surface loads ----

Horizontal tail surfaces --

Balancing ----------

Maneuvering (horizontal surfaces)

Damping (horizontal stabilizer) ---

Loading for slab tail designs-----

Vertical tail surfaces..

Maneuvering ---------

Damping (vertical surfaces)

Gusts (vertical surfaces) -

Ailerons --------

Maneuvering ---

Wing flaps ----

Special devices ----

Dive brakes ------

Control system loads ---

Elevator systems -----

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CONTENTS—Continued

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Rudder systems ------

Aileron systems.-----

Flap and auxiliary control systems.-

Towing and launching (release mechanism) control systems

Ground loads.------

Level landing--------

Level landing with side load...

Nose-down landing---

Head-on landing.

Wing-tip landing --

Launching and towing loads

Loads on fittings.

Wing truss strength.-.

Multiplying factors of safety

Fittings-------

Castings -----

Parallel double wires.-

Wires at small angles ----

Double drag trusses ----

Torque tubes used as hinges.---.

Control surface hinges and control system joints

Wire sizes--------------------------------

Wing lift trusses ...

Chapter 2

PROOF OF STRUCTURE---

Determination of loadings--

Control systems ------

Flight controls ------

Secondary controls --

Fuselages -------

Weight distribution ----

Structural analysis as criteria of strength..

Mechanical properties of materials

Proof of wings --------

Proof of control surfaces ---

Proof of control systems.-

Proof of landing gears ---

Shock absorption------

Proof of fuselages ----

Combined structural analysis tests -

Load tests -------

Special tests ---

System and component tests -

Test loads apparatus and methods --

Methods of correcting to standard.

Test procedures.-------

Jigs.--

Loading schedule---

Supports---

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CONTENTS—Continued

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Special procedure in limit load tests ------

Special procedure in ultimate load tests -----

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Special procedures when ultimate load tests are conducted in lieu of

stress analysis -----

Check of test structure

Test report------

Wing tests -------

Rib tests--

Selection of ribs --

Wing of uniform chord.

Tapered wing-

Test loadings--------

Test methods.-----

Wing proof and strength

Test loads -----

Test methods

General-------

Mounting---

Chord component

Deflections----

Rigidity--

Test report.------

Control surface tests -----

Tail surface and aileron tests ---

Test loads ----

Kinds of tests ----

Load distribution-tail surfaces

Ailerons -----

Balance area---

Test methods.

Horns -------

Mounting------

Fabric covering-

Brace wires ---

Load application.

Test report--

Flap tests --------

Test methods and loads

Test report----

Control system tests -

Test loads -------

Operating test..

Strength tests.-

Test methods---

Method of load application

Application ----

Operation test.------

Ultimate load test--

Rigidity -------

Test report..

Fuselage tests ---

Test loads ----

CONTENTS—Continued

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Test methods -----

General...

Bending test-----

Torsion test ----

Towing and launching lo

Test report-------

Flight load tests ------------

Flutter and vibration prevention tes

Ground vibration tests --

Simplified flutter criteria----

Wing flutter criteria.

Wing torsional stiffness --

Aileron balance criterion.

Free play of ailerons ----

Frequency of ailerons, dive brakes, or spoilers

Empennage flutter criteria -

Elevator balance---------

Parallel axis criterion.--

Perpendicular axis criterion

Rudder balance-----

Tab flutter criteria.

Balance weight attachment criteria

Flight flutter testing ---

Acceptability-------

Records--

Test procedures ---

Chapter 3

DESIGN, CONSTRUCTION AND FABRICATION-

Processes --

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Wing design.-

Torsional stiffness---

Wing design details.

Solid wood spars

Built-up wood spars.--

Splices in wood spars -

Wood leading edge.-

Wood ribs ----------

Trailing edges ------

Wing tips bows--

External brace struts.-

Jury struts..

Wing fittings -------

Fabric covering-------

Metal covered wings --

Control surfaces design.

Control surface stops --

Hinges ------

Installation.--

Elevators -----

Tabs --------

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