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Technical Design Report for Engine Powered Airplane, AIAA GIKI Chapter

Technical Report · May 2014

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Airex’13 XEPAC

AIRPLANE DESIGN
REPORT
PAKISTAN INSTITUTE OF ENGINEERING AND APPLIED SCIENCES
NILORE ISLAMABAD
 Pakistan Institute of Engineering and Applied Sciences 2

INTRODUCTION
This report has peculiarly been written for the AirEx’13 Flying
Competition namely XEPAC organized by GIK Institute. Several other flying
competitions like DBFC are also organized with the collaboration of American
Institute of Aeronautics and Astronautics. XEPAC event has certain requirements
and conditions regarding the design of airplanes for competition which are all
satisfied by the team Fiery Fighters in designing the plane “DragOn”.

This report examines the numerous possible aircraft configurations using

different NACA profiles and provides the right model with the required flight
performance. Construction techniques for building the airframe are also discussed.
Nevertheless some of the information might be applicable for other models like
gliders, but it is solely composed for the Engine Powered Aircraft. Report
comprises of certain categories in which descriptions are subdivided in order to
make it easier to read and understand. For the design of DragOn, preferred
construction method was to utilize the kind support of workshop staff and faculty
members of PIEAS; however Team did purchase some special aircraft instruments
on their own.

Much of the details regarding aerodynamics have been discussed which

vividly exhibits the essential difficulties and requirements that are mandatory for a
safe flight. Facts and figures mentioned in this report comprise of simulations on
various softwares and further elaboration of the dimensions was done by drawing
different views on full scale. It consumed massive time to compile the whole
journey of this competition in this report and to its completion with multiple
effects. Writers believe that it would least likely to be the report considered for
further modifications and improvements.
 Pakistan Institute of Engineering and Applied Sciences 3

ACKNOWLEDGEMENTS
The writing of this report has taken inspiration, help and a fair amount of
time. Inspiration came from DBFC-8 team of PIEAS; one of whose members is the
Team Leader of Fiery Fighters. Motivated by Dean of Engineering, Engr. Dr.
Mohammad Javed Hyder, team Fiery Fighters lay high visions over the XEPAC
event of Airex’13 held in GIKI. Additionally he issued us some books on Aircraft
Aerodynamics which provided healthy knowledge for the understanding of drags
and lifts in various parts of the airplane.

Despite the supervision of Dean of

Engineering on our project, Team Fiery
Fighters is thankful to their Head
Department of Mechanical Engineering,
Dr. Rizwan Alim Mufti who permitted us
to operate different machineries for the
cutting of wood.
 Pakistan Institute of Engineering and Applied Sciences 4

It is worth mentioning the family members of Team Fiery Fighters. It was

the moral support of parents and siblings of all five members in this team which
led to the completion of the project Engine Powered Aircraft.

We are very grateful to Muhammad Al, Zeeshan Nayyar, Hammad Hassan

and Hammad Aslam Bhatti for giving media coverage to our project. It is because
of them that we have now saved memorable pictures proving our sincerity and
devotion towards the project. They also designed T-shirts for the moral support of
our team.

Many books and articles were consulted in the preparation of this report, yet
special gratitude needs to be made of Allah Almighty who helped us achieve the
goals. Success is our motto and effort was our intention which could only be
achieved with firm faith and belief in Allah. Team Fiery Fighters have put all their
sweat and blood for the continuation of the project and now hopes for the triumph.
 Pakistan Institute of Engineering and Applied Sciences 5

Table of Contents
1.0 Executive Summary………………….……………………………7
2.0 Management Summary…………………….………………….......9
2.1 Team Management……………………………………………….......9
2.1.1 Task Distribution…………………………………………..9
2.1.2 Contribution towards Task………………………………..12
2.1.3 Contribution by Volunteers…………………………….....14
2.2 Milestone Chart……………………………………………………...15
3.0 Conceptual Design…………………………………….................17
3.1 Mission Requirements……………………………………………….18
3.1.1 Design Requirements………………………………….......18
3.1.2 Translation of Mission into Design Requirements……......20
3.1.3 Review of Concepts and Configurations……………….…21
3.2 Fuselage………………………………………………………….….21
3.2.1 Internal Structure of fuselage………………………….…21
3.2.2 Figures of Merit……………………………………….….21
3.2.3 Fuselage Configuration…………………………………..22
3.3 Wings Designing……………………………………………………23
3.3.1 Selection of Wing Configuration……………………...…23
3.3.2 Figure of Merit………………………………………...…26
3.3.3 Wing Positions………………………………………...…27
3.3.4 Airfoil Selection……………………………………….....28
3.4 Empennage (Tail Assembly) …………………………………….....29
3.5 Propulsion System Configuration………………………………..…31
4.0 Preliminary Design……………….…………………………...…33
4.1 Design Methodology………………………………………………..33
4.2 Optimization Tools………………………………………………….34
4.3 Design Constraints………………………………………………….35
4.4 Design Measurements………………………………………………36
4.4.1 Wings…………………………………………………….36
4.4.2 Wing Area………………………………………………..37
4.4.3 Wings Span………………………………………………37
4.4.4 Airfoil…………………………………………………….37
4.4.5 Empennage and Fuselage…………………………...……44
 Pakistan Institute of Engineering and Applied Sciences 6

4.4.6 Sizing of Fuselage…………………………………………44

4.4.7 Horizontal Tail……………………………………………46
4.4.8 Vertical Tail……………………………………………….46
4.4.9 Propeller…………………………………………………..46
5.0 Detailed Design……...……….…………………………………..48
5.1 Mission Performance………………………………………………..48
5.2 Major Dimensional Parameters of Aircraft…………………………48
5.3 System Design Integration…………………………………………..49
5.4 Aircraft Weight and Balance………………………………………..50
5.5 Drawing Package……………………………………………………51
6.0 Manufacturing Plan and Processes.………………………………54
6.1 Wings………………………………………………………………..54
6.2 Material of Airplane…………………………………………………56
6.3 Engine Selection……………………………………………………..57
6.4 Tail…………………………………………………………………...58
6.5 Landing Gear………………………………………………………...58
6.6 Rated Aircraft Cost…………………………………………………..60
7.0 Test Plan and Performance Results……………………………....62
7.1 Test Objectives………………………………………………………62
7.1.1 Wing Bending Stiffness test……………………………….62
7.1.2 Material Testing…………………………………….……..62
7.1.3 Landing Gear Test………………………………….……..64
7.1.4 Control System test……………………………………….65
7.1.5 Radio Range Test…………………………………………65
7.1.6 Pre-Flight Checklist…………………………………….…65
8.0 References
9.0 About the Author(s)
 Pakistan Institute of Engineering and Applied Sciences 7

1.0 Executive Summary

This report contains all the essence of the hard work put in by the team of
five students from Pakistan Institute of Engineering and Applied Sciences (PIEAS)
of Mechanical Engineering Department for the AirEx Innovation Challenge held
at GIKI. We believe in the spirit of competition that claims to help students apply
their theoretical and practical knowledge gained in the life through engineering and
other sources and to improve their abilities and potential in the engineering
discipline.

The main incentive of the report is to explain all the basics involved in
designing and manufacturing of the airplane “DragOn”. Our project comprises of
designing of an Airplane, with the main purpose to cope-up with the requirements
of the competition.

Before switching to the engineering of aircrafts, basic aerodynamic science

was understood by arranging regular team meetings and webinars. Study of
aerodynamic concepts made the team capable of defining the design variables of
the project. On the basis of explicit figure of merits the most suitable configuration
of airplane was selected in the conceptual design phase.

After the selection of initial design, the evaluation of the design variables
was held in detailed calculation sessions. Drawing on CAD and simulation of
designs and performance was done in preliminary design phase. The detailed
design phase of the project covers all the iterative approaches toward the
improvement in the design and calculations. At the end of October, manufacturing
was started. Usually hand tools were used and more than half manufacturing was
done in the room of hostel, just like work in a domestic workshop. The
manufacturing team also availed the facility of mechanical engineering workshop
and wood workshop of the university.

The main constraints imposed by the liaison package were; (1) size of
dimension box i.e. 3ft×2ft×1ft, (2)total take-off weight should be less than 10kg,
(3) tip to tip measurement of wing span should be less than 6ft, and (4) the plane
must be capable of carrying 1kg payload. The grading criteria will be based on
fabrication video, test flight video, design report and flying in the event.
 Pakistan Institute of Engineering and Applied Sciences 8

10 kg
Airplane
Weight

Engine Driven
1 kg payload
Plane

200 m 6 feet Wing

Runway span

3×2×1
Storage Box

Each team will be assigned the task to perform maximum numbers of

specific maneuvers. The plane DragOn is designed and manufactured by the way
to meet all these constraints and mission requirements. 15cc ASP engine was
selected after the keen observation and analysis of different engine brands. A 12×6
propeller was found to be compatible with the selected engine. Predicted aircraft
performance capabilities for the mission-1 and mission-2 are as follows:

Performance Parameters Mission-1/Mission-2

Take off distance 10 ft / 15 ft
Wing Loading 0.013 lb.in-2 / 0.016 lb.in-2
Cruise Speed 100 fts-1 / 90 fts-1
Gross Take-off Weight 8.8 lb / 11 lb
 Pakistan Institute of Engineering and Applied Sciences 9

2.0 Management Summary

Keeping in view the need for an effective collaboration spirit, we devised
our management plans the best way we could within the domain of limited
resources and time.

2.1 Team Management

Fiery Fighters consists of a total of five members, all from Mechanical
Engineering Domain, ranging from sophomores to seniors and led by Ikram Arif.
The versatility of experiences of the team members provided the sound basis and
safe environment for the work to be done effectively. The healthy environment,
created under the able and vision oriented guidance of Engr. Dr. M. Javed Hyder,
allowed us to tackle difficult challenges throughout the project efficaciously.
Under all circumstances due to his problem solving approach and secretarial
assistance to the members, our team has been unified like a bond in front of the
stream of difficulties faced during the project.

2.1.1 Task Distribution

The following organogram shows the division of work pursued by the team:
 Pakistan Institute of Engineering and Applied Sciences 10

2.1.1.1 Aerodynamics
This portion was covered by all members of the team who analyzed different
configurations critically and selected the most suitable design to optimize the
mission score, ensure adequate stability and control. The study of induced drag,
parasite drag, skin friction drag and form drag assisted in designing most
appropriate shape. Aerodynamics immensely helped in studying, improving and
predicting the flight performance parameters.

Figure 1: Forces shown during a stabilized climb

2.1.1.2 Structures
In this genre, different types of structures (e.g. monocoque structure, truss
type structure) were initially analyzed after certain aerodynamics testing and most
feasible of them all was then emphasized depending upon the requirements of the
competition. Applicable manufacturing processes for the designing were then
employed followed by fabrication processes. This portion was mainly covered by
Ikram Arif and Nofal Khan.
 Pakistan Institute of Engineering and Applied Sciences 11

Figure 2: Monocoque and Truss type structure

2.1.1.3 Simulations and AutoCAD

AutoCAD software was used to create and compile the drawings and models
of parts, components, sub-systems, and assemblies for concept visualization,
design optimization, and construction plans. Simulations were carried on XFLR5
iterating different configurations of Lift Coefficients, Reynolds Number and other
variables on the given airfoils. AutoCAD was operated by Waqas Afzal whilst
simulations on XFLR5 were compiled by Waleed Yousuf.

2.1.1.4 Report Writing

In report writing, team members especially Hassan Irtza burnt midnight oil
to produce a fine document ideologically explaining all the facts and concepts
related to the design and manufacturing of the airplane. Minor support was
provided by Ikram Arif and Waleed Yousuf in further improving and proof
reading this report.
 Pakistan Institute of Engineering and Applied Sciences 12

2.1.2 Contribution towards Task

To comfort and smoothen the process of task division and to complete the
whole task in limited time and resources, the team was divided such that every task
was performed or assisted in all possible ways by the other team members. The
following graph envisages this fact clearly.
 Pakistan Institute of Engineering and Applied Sciences 13

WORK CONTRIBUTION SUMMARY

Ikram Arif Waleed Yousaf Hassan Irtza Chaudhry Nofal Khan Waqas Afzal

40

40
35

35

35
30

30

30

30
25

25
20

20

15

10

10

10
10

10
10
10
5

MARKETING MANUFACTURING REPORT WRITING SIMULATIONS AERODYNAMICS

 Pakistan Institute of Engineering and Applied Sciences 14

2.1.3 Contribution by Volunteers

Efforts of all the members who worked voluntarily for this project are
graphically presented below. Without their moral and technical support, Team
would not have achieved its milestone. Their contribution towards the media and
technical tasks is shown by the following graphs:

Media Support
40

35

30

25

20

15

10

0
Zeeshan Nayyar M. Ali Shahbaz Hammad Aslam Hammad Hassan

Technical Support
50
45
40
35
30
25
20
15
10
5
0
Mazhar Iqbal Shahid Waqas Umer Hayat M. Ali Shehroze
Shahbaz Ahmad
 Pakistan Institute of Engineering and Applied Sciences 15

2.2 Milestone Chart

Pakistan Institute of Engineering and Applied Sciences 16
 Pakistan Institute of Engineering and Applied Sciences 17

3.0 Conceptual Design

The conceptual design was initiated after completely analyzing the mission
requirements which later helped the team in converting their mission variables to
design constraints. The key system requirements are then defined as figures of
merit (FOM) and used to weigh different concepts against each other.

Various factors that were considered during the construction of airplane are
cost effect, complexity of the design, resources available and the described
constraints including the climatic factor. During the conceptual design phase, the
team aimed at choosing an aircraft configuration to optimize for performing each
mission through an explicit Figure of Merit (FOM) screening process and it was
inferred that Monocoque be suitable on the selected profile.

Vertical and Horizontal fin, landing and nose gears, and payload
configurations were narrowed using the same process. Our incentive was to design
and construct an aircraft that would complete all missions in an efficient manner.
The final aircraft design concept would be entrusted to complete each mission
efficiently while having an optimal rated aircraft cost and would somehow appear
in the form shown below.

Figure 3: Free hand sketch of Conceptual Design

 Pakistan Institute of Engineering and Applied Sciences 18

3.1 Mission Requirements

Mission requirements can be divided into three phases; 1st phase, 2nd phase
and 3rd phase. 1st phase (10%) consists of fabrication video, 2nd phase (30%) of
test flight video and third phase (60%) of design report and final flying. The
following pie graph shows the division of marks among all the phases:

MISSION REQUIREMENTS
Fabrication Video
Tasks with payload 10%
20%

Test Flight Video

Tasks without 5%
Payload
20%

Landing
10%
Design Report
Take off
25%
10%

3.1.1 Design Requirements

All the mission requirements were converted into design requirements after
a long series of meetings among all the members of the team. Conceptual
design was covered up greatly in this regard and all the limits of project were
perfectly defined. The following areas were the main factors in deciding the
scope of design requirements:

3.1.1.1 Weight
According to the liaison package, aircraft TOGW (Take off Gross Weight)
was required to be kept less than 10 kg. As per the design it was limited to 4.5
kg (including payload) in our calculations of aerodynamics. The reasons for the
 Pakistan Institute of Engineering and Applied Sciences 19

decision were justified by different factors like material selection and effective
maneuvering.

3.1.1.2 External payload

The external payload was restricted at 1kg. In conceptual phase, this was
added to the weight of airplane for defining all the aerodynamics of the model
DragOn. The space for keeping the payload was decided to be created inside the
fuselage of airplane.

3.1.1.3 Storage Case

Keeping in the view the restriction of fitting the airplane in a 2 feet wide, 1
feet high by 3 feet (3×2×1) long (interior dimensions) box; all the dimensions
of the component of the airplane were calculated. Maximum wingspan of the
airplane was also restricted to 4.67(56 in) according to the competition package.

3.1.1.4 Fabrication and Test Flight Video

It was aimed to employ volunteers for the making of fabrication video. The
areas to be emphasized in the video included fabrication steps of all the
components of airplane. The testing flight venues were selected according to
expected weather and security conditions.

3.1.1.5 Report Writing

In report writing genre, different sections were outlined and an expected
routine for the task was critically analyzed keeping in the view trivial and non-
trivial parts of the report. The important parts of the report like summary,
detailed design and innovative ideas were also discussed during the
conceptual phase.

3.1.1.6 Take-off and landing

It was a major objective of a team to achieve possibly the smoothest take-off
and landing. Flight performance was also taken into account. Different factors
were considered during team meetings that could enable maximum maneuver.

3.1.1.7 Material and Strength

The usage of building material was restricted to balsa wood, carbon fiber,
Aircraft quality plywood, Styrofoam and composite. Based on strength to
 Pakistan Institute of Engineering and Applied Sciences 20

weight ratio and quality of material balsa wood and aircraft plywood were
selected after their confirmation from tensile testing.

3.1.2 Translation of mission requirements into design

requirements
All the design considerations were defined keeping in view all the
constraints provided by the liaison package of AirEx Competition. In addition to
this, all the working strategies were mapped out which eventually led to the
formation of Multi-disciplinary Optimization (MDO) at latter stage in
preliminary design. Scoring scheme also laid out the foundation in establishing a
result oriented direction for all the trivial and non-trivial goals to be achieved
through the project.

Chart Title
Weight

External Payload
5% 10%
5% Storage Case
20%
5%
Fabrication and Test Flight Video
15%
10%
Report Writing

10% Take off

20%
Landing

Tasks with and without payload

Material and Strength

 Pakistan Institute of Engineering and Applied Sciences 21

3.1.3 Review of Concepts and Configurations

Configurations Alternative Solutions
Wing Monoplane Biplane Flying wing Canard
Tail conventional cruciform V-tail T-tail
Engine placement pusher tractor -------- ---------
The final selection of most suitable configuration is based on some figure of
merits discussed below:

3.2 Fuselage
3.2.1 Internal Structure of Fuselage
Fuselage can be made by using two designs Monocoque and truss. Both
have their own advantages and drawbacks. We intended to build fuselage by the
combination of both structures. Front part of fuselage is made of truss
structure and back part of Monocoque because the front side has to bear more
force than back part and trusses are best at experiencing loads.

Strength of Monocoque is based on external skin whereas strength of truss

structure depends upon internal skin mainly on the two force member truss. Truss
is a strong structure because the two force members of truss can bear too much
force which can be payload or drag force. It is not that much stronger because it
consists of simple rings connected through stringers. Monocoque is heavier
structure due to hard external material whereas truss can be made in light weighted
feature by using a simple fabric to cover the external environment. Covering
material of Monocoque can be metal or composite whereas for truss covering
material can be simple fabric or composite.

3.2.2 Figure of Merit

Truss structure is difficult to manufacture because it consists of higher
number of joints. Monocoque dominates truss structure because it is easier to
manufacture because this structure consists of lesser number of joints with similar
strength. Monocoque costs less as compared to truss structure but truss structure is
comparatively expensive because considerable amount of wood is wasted during
its construction.
 Pakistan Institute of Engineering and Applied Sciences 22

Figure of merit for the front and back part of fuselage are prepared

3.2.2.1 Figure of Merit (Front part of fuselage)

F.O.M Fuselage Configuration
Features Weightage Truss Monocoque
Weight 40 1 0
Bending stiffness 10 -1 1
Manufacturing 20 -1 0
complexity
Strength 40 1 0
Total 100 50 10
Figure 4: Weighted Decision Matrix for Front part of Fuselage

3.2.2.2 Figure of Merit (Rear part of fuselage)

F.O.M Fuselage Configuration
Features Weightage Truss Monocoque
Weight 40 1 0
Bending stiffness 40 -1 1
Manufacturing 20 -1 0
complexity
Strength 10 1 0
Total 100 -10 40
Figure 5: Weighted Decision Matrix for Rear part of Fuselage

3.2.3 Fuselage Configuration

Of all the possible types of fuselage, frequently used ones are blended,
cross-sectional (round) and lifting.
 Pakistan Institute of Engineering and Applied Sciences 23

Blended type and conventional fuselage shapes are very likely to be used
because light weight, optimum yield strength, optimum tensile strength, fatigue
resistance, less manufacturing complexity and lower cost.

Lifting fuselage shape provides high lift and reduces wing loading by
degrees but the fact is that it is very hard to manufacture such shape practically due
to excessive airfoil thickness.

3.3 Wings Designing

3.3.1 Selection of Wing Configuration
Available wing configurations include mono-plane, bi-plane, flying wing
and canard. Biplanes, flying wing and canard have an edge over the monoplane
that all of them have higher lift values as compared to monoplane. But all of them
are heavy weighted planes and too hard to manufacture. So monoplane dominates
the other planes as it is easy to manufacture, light weighted and has better stability
and control features. Hence we have selected Monoplane for our project.

3.3.1.1 Conventional Monoplane

A conventional configuration can be used as a baseline for comparing the
configurations. The performance characteristics would be easily predicted with
ample historical data available. The design was adopted due to the simplicity and
the handling of the aircraft to accomplish the mission. Conventional aircraft with a
 Pakistan Institute of Engineering and Applied Sciences 24

simple fuselage and empennage and a single wing is comparatively easy to design,
manufacture, and fly.

3.3.1.2 Flying Wing

A pure tailless flying wing offers lower cost due to its lack of a tail and a
small fuselage. In addition, a flying wing would offer limited structural weight and
drag. However, it had poor handling qualities and would require sophisticated
augmentation to perform the optimum mission profile. It is very complex to
manufacture.
 Pakistan Institute of Engineering and Applied Sciences 25

3.3.1.3 Canard
A canard design would allow for the horizontal control surface to not detract
from the overall lift of the aircraft. This configuration would have good stall
characteristics, but be limited during takeoff. Manufacturing canard is harder than
other planes.

3.3.1.4 Bi-plane
A bi-plane configuration would be able to produce a large amount of lift
with smaller wings; however, cost is very high for multiple wings. A bi-plane
would be very similar to a conventional design with respect to flight
characteristics. Essentially a dual-wing aircraft, the effective increase in wing area
can give higher payload capacity but at the cost of added weight and drag.
 Pakistan Institute of Engineering and Applied Sciences 26

3.3.1.5 Blended-Wing-Body
The blended-wing-body has handling qualities similar to that of
Conventional Configuration and has shape similar to that of Flying Wing, but
provides lesser drag due to blended intersections and a more streamlined shape. It
could also have a higher RAC due to increased fuselage volume. It is difficult to
manufacture when compared with conventional plane.

More detailed analysis would be necessary if one configuration would not

have appeared superior based on the FOMs.

3.3.2 Figures of Merit

F.O.M. Wing Configurations

Features Weightage Mono-plane Bi-plane Flying Wing Canard

Lift 20 0 +1 +1 +1
Drag 10 +1 -1 +1 -1
Weight 40 +1 -1 0 0
Manufa 10 +1 0 -1 0
cturing
Comple
xity
 Pakistan Institute of Engineering and Applied Sciences 27

Take off 10 +1 +1 0 +1
distance
Stability 10 0 -1 -1 0
and
Control
Total 100 60 -30 10 20
Figure 6: Weighted Decision Matrix for Wing Configurations

3.3.3 Wing Positions

There are three wing positions available for the project as following:

1. High wing
2. Middle wing
3. Low wing

High wing and middle wing positions have an edge over the low wing
position because the wing has to face less drag with high or middle winged
position. Middle wing positioning is better than because of the better stability
and control features in the former. Similarly high winged position airplane is
easier to maintain and increases dihedral effect. Dihedral effect makes the
airplane laterally more stable.

Middle Wing Plane Low Wing Plane

 Pakistan Institute of Engineering and Applied Sciences 28

High Wing Plane

3.3.4 Airfoil Selection

Of all the available airfoil series, NACA and Eppler are the ones frequently
used. Due to easy access to technical data of NACA airofoils, Fiery Fighters opted
for NACA (6412) airfoil for the airplane; configuration of airfoil is semi-
symmetrical. Semi-symmetrical and flat bottom configurations are easier to
manufacture and provide high lift and low drag features.
 Pakistan Institute of Engineering and Applied Sciences 29

Figure 3: Types of Conventional Airfoils

3.4 Empennage (Tail Assembly)

Many empennage configurations were researched based upon prior
competition entries and team experience. Three primary configurations were
chosen from several options to best suit the aircraft weight, stability, and case
sizing requirements.

3.4.1Conventional
The conventional tail generally contributes to a lower aircraft weight and
provides good performance and control due to being in the proper shape.
 Pakistan Institute of Engineering and Applied Sciences 30

Figure 7: Conventional Tail

3.4.2Cruciform
A cruciform tail improves control effectiveness during stall by removing the
horizontal tail from the wing’s “shadow,” but loses the prop wash advantages. This
helps stabilize the airplane easily but is difficult to design since it requires
bisection of elevators which must entirely be symmetrical for the plane to take off.

3.4.3V-tail
The V-tail provides a means to provide an equal control volume as the
conventional or cruciform tail, but with a lower height which conserves case, space
and weight.
 Pakistan Institute of Engineering and Applied Sciences 31

After focusing thoroughly all possible types of empennage, it was inferred

that conventional tail must be followed for this project. There are certain reasons
for choosing this tail structure. It is lighter as compared to other tails. It offers
stability and easier control terms for the airplane design. It is easier to manufacture
on small scale. It is cost efficient since it consumes less material. It facilitates the
balancing of center of gravity (C.O.G.) as compared to other tail structures.

3.4.4F.O.M
F.O.M. Tail Configurations

Features Weightage Conventional Cruciform V-tail T-tail

System Weight 40 0 -1 0 0
Control 40 1 0 -1 1
Height 10 0 -1 0 0
Manufacturing 10 1 -1 0 -1
Complexity
Total 100 50 -60 -40 30
Figure 8: Weighted Decision Matrix for Tail Configurations

3.5 Propulsion System Configuration

Two configurations for engine placement were considered which are detailed
below:

3.5.1Tractor
The engine and propeller are mounted at the nose of aircraft. It keeps the
system weight low and provide ease to manage center of gravity.
 Pakistan Institute of Engineering and Applied Sciences 32

3.5.2Pusher
The propeller is mounted behind the fuselage and engines thrust provide
push to the plane. It creates issues in tail balancing, propeller efficiency and take-
off performance.

3.5.3Figure of Merits
Configuration Pusher Tractor
FOM Weightage Scoring
System Weight 40 0 0
Take-off 30 0 0
Performance
Thrust 20 -1 1
Aircraft 10 0 0
Torqueing
Total 100 -20 20
Figure 9: Weighted Decision Matrix for Propulsion System

From these FOM, single tractor was chosen as the most efficient and good
performer.
 Pakistan Institute of Engineering and Applied Sciences 33

4.0 Preliminary Design

With the general aircraft configuration selected from the conceptual phase,
the aerodynamics and structural groups helped initiating preliminary design within
their respective areas of specialty. The first step during this phase was initial sizing
of major components. This portion was equally subdivided amongst the members
with their free will of selection. Dimensions of ailerons, rudder, and elevator etc.
were calculated after selecting wing span, fuselage length and other necessary
dimensions. Selections of NACA 6412 airfoil for the Wings and NACA 0012 for
the empennage lead to all these calculations. Full scale drawings were also drawn
on A-1 sheet. Performance predictions were then made based on the optimization
configuration.

The chosen configuration from the conceptual design phase was separated
into two groups: aerodynamic and structural groups. Critical design parameters
were selected and studied within each group. FOMs were used to find appropriate
sizes for many of the design parameters. The mission model program from the
conceptual design phase was modeled more accurately and a propulsion
performance program was created. These programs optimized the most important
design parameters, while the remainder of the design parameters where
subsequently analyzed and sized.

4.1 Design Methodology

The preliminary phase focused on taking the configuration developed in the
conceptual phase and defining it quantitatively in terms of basic characteristics
such as wing area, wing span etc. The goal was to develop a design that would
achieve the highest score possible. The analysis was performed primarily with the
aid of a unified Multi-Disciplinary Optimization (MDO) program. The program
itself was partitioned into two separate codes: one primarily for aerodynamic
analysis and one for structural analysis. Since these programs were distinct and
capable of being run independent of the other, it was important to maintain good
communication between the two groups. Output generated by the aerodynamics
team would be used as input for propulsion and vice versa. As numerical values
regarding flight performance became available and eventually more accurate, the
structures team was able to begin their portion of analysis as well. Structures relied
mostly upon physical testing supplemented with simple analysis and interaction
 Pakistan Institute of Engineering and Applied Sciences 34

with the CAD lead. Several iterations of MDO analysis and physical testing were
necessary to be sure the team as a whole was converging toward a uniform and
optimum solution.

The results of the optimization led to an airplane with a wing area of 700 in²,
an aspect ratio of 5, a fuselage length of 46in and a 12x8 inch propeller. The
detailed aerodynamic analysis led to the selection of the NACA-6412 airfoil for the
wing and the conventional tail surfaces. In the detailed design analysis the final
components for the airplane were selected, and the manufacturing drawings of the
airplane were generated.

4.2 Optimization Tools

The MDO (Multi-Disciplinary Optimization) program was used find
optimum aircraft configurations. It helped us to predict optimum aircraft
configuration parameters and constraints in a logical and disciplined way. Using an
iterative approach, we concurrently analyzes aerodynamics, structures and mission
requirements. Results of MDO were best design in limited resources, better
stability and control and maximum score.

Following is the flowchart representing our basic utilization of the MDO

program.

After MDO
Aerodynamics Mission Best design in
Structure Requirements limited
No balance in Poor ideas resources, better
resources and about Good ideas at start stability and
engineering structures but poor control,
knowledge management maximum score

Figure 4: Multi-Disciplinary optimization (MDO)

 Pakistan Institute of Engineering and Applied Sciences 35

Program inputs were required to establish baseline criteria and compute

overall score. These criteria included airfoil properties such as sectional lift and
drag curves. Mission cruise speed, power requirements, span, and aspect ratio
constraints were established to maintain realistic solutions. The propulsion analysis
program inputs included motor, propeller, and battery characteristics and aircraft
aerodynamic parameters.

From these inputs, takeoff performance, cruise conditions, energy

consumption, and endurance capabilities could all be calculated. Furthermore,
efficiencies and flight conditions for each mission segment could be examined in a
way to design an aircraft that would achieve the highest contest scores. Wind
inputs were also utilized to determine each aircraft’s performance at different
environmental conditions. These baseline results were used by the MDO code to
calculate and compare the score of alternative configurations in order to produce
the highest scoring designs.

The models used in the program include aerodynamic, structural, and

mission and design relationships. Aerodynamic modeling was performed using a
combination of lift theory using sectional airfoil data and drag formulas based on
specific methods. The structural model is empirically based on conservative
estimates for weight of the airplane. Along with the aerodynamic analysis, a
structures program was utilized in order to optimize structural components of the
airplane. The aerodynamics and structures teams conducted an iterative process
with both programs to arrive at the optimal aircraft and power plant configuration.

Optimization outputs were based on localized maximum scores generated

for each aircraft configuration. Several outputs were generated and used to
determine trends for each input scenario. Optimized outputs were used alongside
sound engineering experience and judgment to determine final aircraft geometry
and power requirements.

4.3 Design Constraints

Critical design parameters were selected within each design group. The
aerodynamic group investigated wing area, airfoil, wingspan, and fuselage and
empennage size, while the structures group investigated boom length and payload
amount (1kg) was taken from the competition rules.
 Pakistan Institute of Engineering and Applied Sciences 36

Design Variables
Aspect Ratio

Wing Loading

Cubic Loading

Stall Speed
9% 10%

9% 9% Engine performance

Desired lift
9% 9%
Drag

9% 9%
Take-off speed

9% 9%
9% Horizontal tail location on vertical
tail
Wing tip and root thickness to
chord ratio
Horizontal tail root thickness to
Chord ratio

4.4 Design Measurements

4.4.1 Wings
In order to size the wing structure, estimates of lifting loads were generated.
Based on initial weight predictions, the wing lift distribution was determined.
Mission analysis indicated that the designed wing can bear the estimated load that
would be encountered during the high-speed turns during our mission.

The expected root moments were then determined based on the lift
distribution and dynamic loads. Structural tests indicated a need for two wing spars
in order to provide adequate torsional rigidity. Basic bending and torsion tests were
conducted on generic wing sections with different material properties for the
maximum predicted aerodynamic loads. The tests focused on structural weight and
rigidity.
 Pakistan Institute of Engineering and Applied Sciences 37

A very stiff wing would provide more than adequate rigidity at the expense
of added structural weight. Therefore, tradeoffs were made to reduce the weight by
scaling back the rigidity of the wing to only withstand a minimal amount of stress
beyond our predicted flight loads.

Variables Measurements
Span 56 in
Chord 12 in
Aspect ratio 5

4.4.2 Wing Area

Wing area is crucial for take-off with a short runway. High wing loading
allows for faster cruise velocities but longer take-off distances. For designing the
wing area, the structural wing strength was required.

The wing chord is optimized at 12 inches. The wing area was established
based on a simple rectangular geometry using 56 in span and a 12 inch chord.

4.4.3 Wingspan
Wingspan has a major effect on wing efficiency and RAC. RAC is
minimized for given wing areas as the aspect ratio is lowered, but high aspect ratio
wings become more efficient. Also, RAC is minimized with a rectangular wing
making elliptical and tapered wings highly penalized. Therefore a RAC/efficiency
tradeoff must be made. Construction, fit-in-box, and the ability to pass the wing tip
loading test were other considerations.

4.4.4 Airfoil
Airfoil selection is important because of its direct effect on take-off and
cruise. Airfoil also plays an important role in the functioning of the aircraft.
Several different airfoils types were considered: high lift airfoil, low drag airfoil
and a balanced airfoil. The three airfoils were chosen based on historical data for
further analysis.

The high lift airfoil will be best during takeoff due to its high lift coefficient,
but its drag possibilities during cruise was a great concern for our team concerning
the rules of the competition. So high lift airfoils where eliminated due to high drag
 Pakistan Institute of Engineering and Applied Sciences 38

possibilities while the low drag airfoil perform well during cruise due to its low
drag coefficients, but its low lift coefficients will be a concern during takeoff.

Figure 10: Wing and Tail design on XFLR5

 Pakistan Institute of Engineering and Applied Sciences 39

An airfoil that was a compromise between low drag and high lift was
chosen. So NACA-6412 airfoil was chosen. Plus the balanced airfoil performed
well in both cruise and takeoff situations.

Figure 11: Airfoil comparison of NACA 6412 against NACA 4418

Pakistan Institute of Engineering and Applied Sciences 40

Figure 6: Batch Foil Analysis for NACA 6412

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Figure 7: Airflow rate versus distance travelled from end to end of airfoil 6412
 Pakistan Institute of Engineering and Applied Sciences 42

Figure 12: Graph of Cl vs Alpha comparing NACA foil 4418 and 6412

Figure 13: Graph of Cl/Cd against Alpha showing comparison of NACA foil 4418 and 6412
 Pakistan Institute of Engineering and Applied Sciences 43

Figure 14: Graph of Cl against Xtr1 showing comparison of NACA foil 6412 and 4418

Figure 15: Graphs of comparisons between NACA 4418 and 6412

 Pakistan Institute of Engineering and Applied Sciences 44

4.4.5 Empennage and Fuselage

It was desired for the entire plane length to be less than 3 feet long so that it
could fit in the box. A one-piece fuselage and empennage would benefit the
structural integrity and weight of the plane. The empennage size must be sufficient
to stabilize the aircraft. As overall aircraft length increases the RAC increases.

Drag decreases as the fuselage length increases and empennage size

decreases. A compromise must be made to minimize both RAC and drag. The nose
and tail sections were determined by conically fairing the main body to increase
aerodynamic efficiency.

Nose length includes a lightly positive inclination from the centerline to

maximize ground clearance for the propeller. The tail cone was extended to
provide maximum moment arm length for the tail. The fuselage structure is
strengthened by the material properties.

4.4.6 Sizing of Fuselage

Variables Measurements
Length 40in
Width 5 in
Height 5in

The tail was sized to provide static stability and dynamic control. This tail
size with a conventional elevator provides sufficient pitching moment and a
relatively high static margin for the aircraft. The vertical tail was also sized in a
similar manner. Considerations for the vertical stabilizer height were made to fit
the aircraft into the smallest case possible and reduce overall system weight. The
rudder was initially over-sized by utilizing a control horn to provide sufficient
control during ground handling.
Pakistan Institute of Engineering and Applied Sciences 45

Figure 16: Fuselage Design on XFLR5

 Pakistan Institute of Engineering and Applied Sciences 46

4.4.7 Horizontal Tail

Variables Measurements
Root chord 7.5 in
Tip chord 5.5 in
Mean chord 6.5 in
Sweep angle 10 degrees
Design Conventional
Aero foil NACA 0012
Span 25 N

4.4.8 Vertical Tail

Variables Measurements
Root chord 7.5 in
Tip chord 4 in
Mean chord 5.75 IN
Sweep angle 20 degrees
Design Conventional
Aero foil NACA 0012
Radar’s width 2.6 In

4.4.9 Propeller
Propeller pitch and size impacts the amount of thrust produced. A propeller
with a high pitch to diameter ratio would be more efficient at higher airspeeds than
a low pitch to diameter ratio propeller. The selection of the propeller required a
careful balance between both pitch and diameter. By using previously compiled
propeller data along with the MDO program, various propellers were studied. The
propeller selection based on a takeoff and flight performance and after the
selection of appropriate engine 12×6 propeller of wood was chosen.
 Pakistan Institute of Engineering and Applied Sciences 47

4.4.10 Control Surfaces

4.4.10.1 Elevator
Variables Measurements
Span 25 in
Chord 1.6 In

4.4.10.2 Ailerons
Variables Measurments
Span 18 in
Chord 2.5in
 Pakistan Institute of Engineering and Applied Sciences 48

5.0 Detailed Design

5.1 Mission Performance
Mission-1 (without payloads)
Parameters Estimation
Time of flight 10min
Number of maneuvers Maximum
Wing loading
Cruise speed 99 ft/sec
Energy consumption

Mission-2 (with payloads)

Parameters Estimation
Time of flight 10min
Number of maneuvers Maximum
Wing loading
Cruise speed 90 ft/sec
Energy consumption

5.2 Major Dimensional Parameters of Aircraft

Fuselage
Length 40in
Width 5in
Height 5in

Wing
Airfoil NACA6412
Span 56in
Chord 12in
Maximum thickness 1.4in
Aspect ratio 4.7
Wing area 672 in2
Taper N/A
Sweep N/A
Aileron span 18in
Aileron Chord 2.5in
Aileron Area 45in2
 Pakistan Institute of Engineering and Applied Sciences 49

Empennage
Horizontal Tail
Span 25in
End chord 5.5in
Root chord 7.5in
Area (excluding elevator) 162.5in2
Elevator span 25in
Elevator chord 2in
Elevator area 50in2
Airfoil NACA0012
Vertical tail
Span 10in
End chord 3.5in
Root chord 7.5in
Area (excluding rudder) 26.25in2
Rudder height 10in
Rudder width 2in
Rudder area 20in2
Airfoil NACA0012

5.3 System Design Integration

5.3.1 Fuselage
Usually fuselage defines the actual shape of aircraft. It also has major
contribution in the total weight. The length of fuselage was decided according to
the dimension box constraint. Three feet long and two feet wide box can easily
comprise 40in fuselage. Front part of fuselage contains fuel tank of 7in length and
3in wide. Engine is mounted on the nose. The rear portion is tapered to reduce the
drag.

5.3.2Wing
A folding wing having two pieces was constructed. Due to dimension box
limitation, single piece wing of 56in could not be placed in the box. Two servo
motors on either side of the wing were attached for the movement of respective
ailerons. Dihedral angle was fixed at zero and wing was at zero degree of angle of
attack. Wing will be clamped on the top of the fuselage by rubber bands.
 Pakistan Institute of Engineering and Applied Sciences 50

5.3.3Landing Gear
Usually two configurations of landing gear are employed in aircrafts;
tricyclic and tail dragger. Since aircraft was designed for zero angle of attack and
taking in account the stability of plane on the ground, ‘tricyclic’ configuration was
selected.

5.4 Aircraft Weight and Balance

5.4.1Aircraft Weight Distribution
Components Weight
Wing 1.68lb
Fuselage 1.87lb
Empennage 0.43lb
Landing gear 0.6lb
Propulsion system 1.72lb
Fuel tank (filled) 1.10lb
Payload 2.21lb
Maximum take-off gross weight 9.62lb

5.4.2CG Balancing
5.4.3Flight and Mission Performance Parameters
Following are important parameters of mission performance:
Parameter Numeric Value
CL (max) 1.28
CD (min) 0.4
Aspect ratio 4.7
L/W Cruise (mission-1) 22.5
L/W Cruise (mission-2) 17.4
Wing Loading (mission-1) 1.6 lb/ft2
Wing Loading (mission-2) 2.1 lb/ft2
Gross take-off weight (mission-1) 7.42lb
Gross take-off weight ( mission-2) 9.62lb
Stall Angle 150
Cruise Speed (mission-1) 99 ft/sec
Cruise Speed (mission-2) 90 t/sec
 Pakistan Institute of Engineering and Applied Sciences 51

5.5 Drawing Package

5.5.1Top View

Figure 17: 2-Dimensional Drawing on AutoCAD showing Top View

5.5.2 Side View

Figure 18: 2-Dimensional Drawing on AutoCAD showing Side View

 Pakistan Institute of Engineering and Applied Sciences 52

5.5.3 3D Drawings

Figure 19: 3-Dimensional Drawing on AutoCAD

Figure 20: 3-Dimensional Drawing on AutoCAD

Pakistan Institute of Engineering and Applied Sciences 53

Figure 21: 3-Dimensional Drawing on AutoCAD

 Pakistan Institute of Engineering and Applied Sciences 54

6.0 Manufacturing Plan and Process

Manufacturing of the airplane not only required quality time and adequate
finances but it also demanded great amount of effort and diligence. The team
“Fiery Fighters” is greatly obliged to the Dean of Engineering Engr. Dr. Javed
Hyder who helped us during the whole manufacturing process through his
effective collaboration and able leadership skills.

The selection of the materials and their application for the project constituted
the main agenda of manufacturing plan. It was important that the airplane be built
in a reasonable time with materials and methods that the team could afford and
were familiar with. It was also important that the airplane be kept light and strong
to increase its performance. A scheduling approach was used to develop the
manufacturing plan to accomplish these goals. With all these considerations in the
mind, we decided to use the Balsa wood, Aircraft ply wood and carbon fiber rods
to build the aircraft. The details of the whole idea are described below for different
components of the aircraft.

6.1 Wings
The manufacturing process was initiated with the construction of wings. The
high wings were made using the aircraft plywood and BALSA wood. The
materials were joined by employing adhesives like Z-POXY, white glue and
GMSA elfy. The high wings were made of detachable characteristics. Detachable
wings were joined using 10 mm and 8 mm carbon fiber rods so that they can be
assembled and dissembled with ease and comfort according to requirement.

The wing is built in two halves. Each half consisted of right and left wing
which were made using the same procedure. The aero foils designed on the
software XFLR5 were manufactured as the first step. The aero foils were made of
BALSA wood and aircraft plywood. They were then joined through 28 inch long
BALSA rod in each half of the wing by using different adhesives and also
strengthened by Balsa wood strips at the lower edges of the wings. Balsa ribs and
balsa sheeting formed the leading edge of the wings. Aero foils were total 14 in
number correspondingly 7 in each wing.

The strength of the wings mainly depended upon the strength of BALSA and
aircraft ply wood. Besides these materials, the wings were strengthened by the
 Pakistan Institute of Engineering and Applied Sciences 55

covering of Monokote TM. Monokote TM also provided a smooth aerodynamic

surface to wings. The strength of the wings can also be increased by the insertion
of carbon fiber or aluminum rods. We opted for carbon fiber rods for strength and
stability.

Wings were connected via carbon fiber rods. The carbon fiber rods have an
amazing feature of offering an optimized solution to the trio of strength, bending
and torsion control. On each wing half, the spars extend out throughout the length
of the wings. The central part of wings runs through the full fuselage width in
order to promote structural efficiency.

Figure 22: Representation of Wings

 Pakistan Institute of Engineering and Applied Sciences 56

Figure 23 Joining of Tail Trusses

6.2 Material of Airplane

We have used Balsa wood and hard aircraft quality Ply wood for the
designing of fuselage, wings and tail assembly because of the following reasons:

1. Wood is a light weighted material and so it can best suit the needs of the
competition.

2. Wood has an advantage that defected parts can be easily replaced.

3. Balsa wood is a normally strong material but in our domain it is workable.

4. Ply wood is also used as material in certain sections of the airplane as it is

useful in the wing-tip test of the airplane.

5. Wood is easier to use in the manufacturing process due to its many features.
 Pakistan Institute of Engineering and Applied Sciences 57

6.3 Engine Selection

The process of engine selection was carried out in the light of aerodynamic
calculations and design based constraints. The weight of the airplane was estimated
theoretically via using certain mathematical techniques. The calculations were
then, triggered with the corresponding thrust producing engines to select the most
suitable engines. Following table takes into account all the available engines
compared according to their thrust producing capability and cost efficiency.

Considering the merger of both the thrust producing capacity and cost
effectiveness, 20 cc ASP gasoline engine (code 91) was chosen. Fuel for this
engine is Methanol+Caster Oil Optimized engine provides about 5.5 kg thrust
which is sufficient to lift the airplane comprising of at most 4.5 kg weight
including 1 kg payload.

Figure 24: Gasoline ASP 91 Engine

 Pakistan Institute of Engineering and Applied Sciences 58

6.4 Tail
The manufacturing of tail was followed after the construction of wings. The
design of the tail was prepared on XFLR5 software which laid the basis for the
manufacturing of tail. Tail of conventional design was made by aircraft plywood
and BALSA wood. The materials were then joined by employing adhesives like Z-
POXY, white glue and GMSA Elfy.

The internal structure of tail was made of PRATT truss structures. The
WARREN truss structure was not used although it is much stronger than PRATT
structure. The main reason for this step was the manufacturing complexity
involved in making the WARREN structure. For this project, PRATT structure was
preferred because it met all the design constraint conditions like bearing maximum
drag and strength vise capability.

Horizontal tail was manufactured by making two trapezoidal flaps and then
joined by a common plywood rectangular rod according to the design of the
empennage assembly. The vertical tail (immovable rudder), which was almost of
trapezoidal shape, was then connected at the top of horizontal tail.

6.5 Landing Gear

The landing gear length was sized to place the aircraft at an initial angle of
12 degrees to the horizontal. This angle is the maximum stall angle of the wing and
provides the best lift for short takeoff. Additionally, the gear’s wheel hub is placed
at a forward station relative to the aircraft’s center of gravity, 20 degrees off
 Pakistan Institute of Engineering and Applied Sciences 59

vertical of its position to ensure static stability while on the ground. Additionally
landing gears were adjusted such that propeller used has a safety clearance from
ground of at least 1.5 to 2inch. From the time that propeller of 12×6 was confirmed
for DragOn, landing gear of size 40 having 6 inch vertical height was used.

Figure 25: Shock Absorbing Landing Gear

Figure 26: Nose Gear

 Pakistan Institute of Engineering and Applied Sciences 60

6.6 Rated Aircraft Cost

Financial management was carried out very efficiently throughout the whole
project. The following table completely states all the items purchased for the
project followed by their cost.

Items Amount
Balsa sheets PKR 9,500
Plywood PKR 800
Monocot Sheet PKR 1,600
Servo Motors (HITEC HS-322HD) PKR 4,400
Hinges and Tyres PKR 780
Miscellaneous PKR 6,610
Connecting and Carbon Fiber rods PKR 1,250
Control Hone and Aileron sheet PKR 220
Fuel Tank PKR 500
Landing Gears PKR 1050
Engine PKR 15,575
Fuselage PKR 2,000
Total PKR 44,285

The following graph gives a glimpse of comparative costs of all the items
purchased.
 Pakistan Institute of Engineering and Applied Sciences 61

Rated Aircraft Cost Balsa Sheets

Plywood

Monokoat Sheet

Servo Motors

2000
9500
Hinges and Tyres

15575 800
1600 Miscellaneous

4400
Connecting and carbon fiber Rods
1250 2610

Control Hone and Aileron Sheet

780
1050
500 220
Fuel Tank

Landing Gears

Engine

Fuselage
 Pakistan Institute of Engineering and Applied Sciences 62

7.0 Test Plan and Performance Results

The testing of various components and assemblies of RC plane was carried out to
ensure the satisfactory results in the test and mission flight.

7.1 Test Objectives

Test objectives were defined within the testing plan to ensure the highest
performance results of aircraft regarding the competition. It includes the testing of
structure, control surfaces and motors, radio range and flight test.

7.1.1 Wing Bending Stiffness Test

Since the wing of aircraft has to carry total weight of the plane,
so it undergoes a distributed loading gradually increasing from tip to
the root of wing. Here, wing behaves like a cantilever beam under
distributed loading. Three point bending test (tip to tip support with
load concentration at the center) was employed to check the stiffness
and cantilever attachment quality of the wing.

Figure 27: Wing Bending Test

7.1.2 Material Testing

In order to check the material properties of balsa and ply wood, tensile
testing of these composite materials was performed in the material
testing laboratory of the institute. The result showed us the toughness
and weight limit of the selected material.
Pakistan Institute of Engineering and Applied Sciences 63

Figure 28: Tensile Testing Machine

Figure 29: Tensile Testing Machine (Continued...)

 Pakistan Institute of Engineering and Applied Sciences 64

Figure 30: Testing Results showing Graph of Ply Wood

Figure 31: Testing Results showing Graph of Balsa Wood

7.1.3 Landing Gear Test

A considerable magnitude of load, in accordance with the predicted
impact loading on during landing, was mounted on the top of the
landing gear and dropped free fall. The results determine the
maximum loading capability of landing gear stand.
 Pakistan Institute of Engineering and Applied Sciences 65

Figure 32: Landing Gear Test

7.1.4 Control System Test

After connecting servo motors with the control surfaces by push rods,
control surfaces were trimmed and servo motor was placed at zero
iteratively. The angle of movement of elevator and ailerons was also
checked and result was matched with the detailed calculations.

7.1.5 Radio Range Test

Before the test flight voltage of radio battery and range of radio
signals were tested in the flight ground.

7.1.6 Pre-Flight Checklist

All the safety parameters, needed before flight, were summarized in a
list to prevent any chance of possible error and failure and to improve
performance results.
 Pakistan Institute of Engineering and Applied Sciences 66

Pre-flight Checklist
Aircraft structural integrity
 Wing
 Fuselage
 Tail
 Control surfaces
 Landing gear
 payloads
Avionics and Controls
 Servo wiring
 Servo motor
 Range test
 Radio and receiver batteries
Propulsion
 Fuel
 Engine starter
 Engine spark plug
 Verify engine working
Final Checks
 Pilot
 Ground crew
 Final visual inspection
 Pakistan Institute of Engineering and Applied Sciences 67

8.0 References
 AIAA-GIKI XEPAC Rules 2013 www.aiaa-giki.com
 Daniel P. Raymer, Aircraft Design: A Conceptual Approach.
 Andy Lennon, Basics of R/C Model Aircraft Design.
 David F.Anderson & Scott Eberhardt, Understanding Flight 2nd Ed.
 Alex Weiss, R/C Sports Aircraft from Scratch.
 OSU Design Report, Cessna/Raytheon AIAA-DBFC 2009/2010.
 PIEAS Drag Fighters Design Report, DBFC8-GIKI 2013.
 Pakistan Institute of Engineering and Applied Sciences 68

9.0 About the Author

Nofal Khan
To see the birds flying in air was always a
fascination to me, and now to finally design and
build something that can defy gravity and tear its
way through air, well that is a dream come true.
As a mechanical engineering student,
aerodynamics always intrigues me. Physics was
always my interest and now I got the ultimate
opportunity to apply my knowledge and see how
things practically behave. Working with my team
to build this aircraft did not only give me
experience, but also an insight to how engineering projects are successfully done.

Hassan Irtza Chaudhry

I believe that the process of Entrepreneurship
drives an engineer’s life. This passion forced me
to get into the team Fiery Fighters. This
competition not only offered me an opportunity to
innovate something but also taught me how to
think on practical grounds.

Ikram Arif
I am from Mechanical Engineering department of
PIEAS. I was internee at Pakistan Ordinance
Factories Wah Cantt. I believe that hard work is
the master key to success. During BS-Engineering,
I participated in Design Build and Fly Competition
held at GIKI and Shell Eco Marathon Asia. Aero
planes and Vehicle designing is my passion. I wish
to travel in a vehicle or airplane on my design. My
 Pakistan Institute of Engineering and Applied Sciences 69

aim of life is to serve my beloved country Pakistan. I love my family and I am very
grateful to the m for supporting me at every step.

Waqas Afzal
I’m a Mechanical Engineering Student at
PIEAS. I believe key to success is hard work
and that it always pays off in the end. I’m a
Cool headed kinda guy who never panics,
even if the situation demands to be, and loses
hope. I always remain positive. I don’t plan
things for future, I like to act instantly, go
with the flow and deal with things as they
come along. I have been the head of Scouting
Department in PIEAS Volunteers Society for
six months and I have shown good leadership
skills, not bragging or something. Planes have
always fascinated me to no end especially engine powered because I love to see
planes fly at the same time I love the sound of the engine.

Waleed Yousuf
Being a Mechanical Engineering Student at
PIEAS and participating in a technical event
held at GIKI, are one of the biggest moments
of honor and proud for me and my well-
wishers. I belong to Bahawalpur and currently
enrolled in 5th Semester at PIEAS, trying to
work with utmost devotion and sacrifice to
learn as much as I can till graduation.
Mechanical Engineering has vastness that
never lasts and manufacturing of an Airplane
is one of its kinds. I am grateful to Allah for
augmenting our spirits and helping us
complete the Engine Powered Aircraft design. I wish to venture all my projects
with equal devotion and become a glowing engineer for the betterment of Pakistan.

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