aerochopper(vtol concept)
TRANSCRIPT
1
Aero-chopper
(VTOL) Supervisor: Mr. Nasser Chakra
by,
Shashank Dathatreya
2
Table of Content INTRODUCTION ............................................................................................................................... 4
UAV Types ................................................................................................................................... 6
Understanding the Project .............................................................................................................. 8
AIM .............................................................................................................................................. 8
ABSTRACT .................................................................................................................................... 8
SCOPE .......................................................................................................................................... 8
Parametric Study ........................................................................................................................... 10
Specifications and details .......................................................................................................... 12
Specifications and details .......................................................................................................... 14
GANTT CHART ................................................................................................................................ 17
DESIGN CONCEPT .......................................................................................................................... 19
COST ANALYSIS .............................................................................................................................. 21
MAN POWER ................................................................................................................................. 23
Cost analysis .................................................................................................................................. 24
Cost of materials and electricals ............................................................................................... 26
Materials ....................................................................................................................................... 27
Tools .......................................................................................................................................... 30
ELECTRICALS .............................................................................................................................. 32
Overview ................................................................................................................................... 33
Overview ................................................................................................................................... 35
Airfoil Selection ............................................................................................................................. 42
AIRCRAFT DESIGN .......................................................................................................................... 47
Structure designing :(PROFILI) ....................................................................................................... 49
3D Drawing .................................................................................................................................... 54
3
CONSTRUCTION (ASSEMBLY) ........................................................................................................ 58
GRAPHS ......................................................................................................................................... 74
Area Calculation ............................................................................................................................ 78
PERFORMANCE ANALYSIS ............................................................................................................. 97
CENTRE OF GRAVITY .................................................................................................................... 128
PERFORMANCE ANALYSIS ........................................................................................................... 132
Troubleshooting .......................................................................................................................... 135
Safety and Risk Assessment ........................................................................................................ 138
CONCLUSION ............................................................................................................................... 139
4
Acknowledgement
Of the many people who have been enormously helpful in the preparation of this
project, we are especially thankful to, Mr. Nasser Chakra for his help and
support in guiding us to through to its successful completion.
We would also like to extend our since gratitude to Emirates Aviation College for
the use of their resources, such as online databases and library, without which
the completion of this project would have been extremely difficult.
A very special recognition needs to be given to Ms. Kavita, our librarian, for her
extensive help and support during research and in dealing with online resources.
In addition, a special thanks to our friends Cibin, Suraj and Yogesh for their help,
consideration and guidance.
Last but not least, we would like to say a special thank you to our parents and
family members for their moral and financial support this semester.
5
INTRODUCTION1
Figure 1
UAV is an acronym for Unmanned Aerial Vehicle, which is an aircraft with no pilot on board.
UAVs can be remote controlled aircraft, for example, flown by a pilot at a ground control
station, or can fly autonomously based on pre-‐programmed flight plans or more complex
dynamic automation systems. UAVs are currently used for a number of missions, including
reconnaissance and attack roles. To distinguish UAVs from missiles, a UAV is defined as being
capable of controlled, sustained level flight and powered by a jet or reciprocating engine. In
addition, a cruise missile can be considered to be a UAV, but is treated separately on the basis
that the vehicle is the weapon. The acronym UAV has been expanded in some cases to UAVS
(Unmanned Aircraft Vehicle System). The FAA has adopted the acronym UAS (Unmanned
1. 1 http://www.theuav.com/
6
Aircraft System) to reflect the fact that these complex systems include ground stations and
other elements besides the actual air vehicles.
Officially, the term 'Unmanned Aerial Vehicle' was changed to 'Unmanned Aircraft System' to
reflect the fact that these complex systems include ground stations and other elements besides
the actual air vehicles. The term UAS, however, is not widely used as the term UAV has become
part of the modern lexicon.
UAV Types
• Target and decoy -‐ providing ground and aerial gunnery a target that simulates
an enemy aircraft or missile
• Reconnaissance -‐ providing battlefield intelligence
• Combat -‐ providing attack capability for high-‐risk missions (see Unmanned
Combat Air Vehicle)
• Research and development -‐ used to further develop UAV technologies to be
integrated into field deployed UAV aircraft
• Civil and Commercial UAVs -‐ UAVs specifically designed for civil and commercial
applications.
Degree of Autonomy
Some early UAVs are called drones because they are no more sophisticated than a simple radio
controlled aircraft being controlled by a human pilot (sometimes called the operator) at all
times. More sophisticated versions may have built-‐in control and/or guidance systems to
perform low level human pilot duties such as speed and flight path stabilization, and simple
prescript navigation functions such as waypoint following.
From this perspective, most early UAVs are not autonomous at all. In fact, the field of air vehicle
autonomy is a recently emerging field, whose economics is largely driven by the military to
develop battle ready technology for the war fighter. Compared to the manufacturing of UAV
flight hardware, the market for autonomy technology is fairly immature and undeveloped.
Because of this, autonomy has been and may continue to be the bottleneck for future UAV
7
developments, and the overall value and rate of expansion of the future UAV market could be
largely driven by advances to be made in the field of autonomy.
Autonomy technology that will become important to future UAV development falls under the
following categories:
• Sensor fusion: Combining information from different sensors for use on board
the vehicle
• Communications: Handling communication and coordination between multiple
agents in the presence of incomplete and imperfect information
• Motion planning (also called Path planning): Determining an optimal path for
vehicle to go while meeting certain objectives and constraints, such as obstacles
• Trajectory Generation: Determining an optimal control maneuver to take to
follow a given path or to go from one location to another
• Task Allocation and Scheduling: Determining the optimal distribution of tasks
amongst a group of agents, with time and equipment constraints
• Cooperative Tactics: Formulating an optimal sequence and spatial distribution of
activities between agents in order to maximize chance of success in any given
mission scenario
8
Understanding the Project
AIM
The Aim of this project is to design and construct an Unmanned Aerial Vehicle which will be a
hybrid between a helicopter and an airplane, so that we can achieve advantages of both
helicopter and airplane.
ABSTRACT
The purpose of this project is to design and construct a tilt-‐rotor aircraft with both a vertical
takeoff and landing. The aircraft being a hybrid of airplane and helicopter, which gives the
structure a superior performance and enhanced abilities having both the functions of a
helicopter and the aircraft, which include vertical take-‐off/landing and required forward speed.
The model aircraft can be constructed with balsa wood or any composite materials. The
airframe consists of the fuselage, which is the main component of the airplane, the wings(large
section of the aircraft), and the empennage (tail section, or tail feathers). The components of
the wings and tail sections are also known as the control surfaces since they are of course
important in controlling the airplane. The attached to the wings are flaps and ailerons. The
empennage is the tail assembly consisting of the horizontal stabilizers, the elevators, the vertical
stabilizer, and the rudder.
SCOPE
Scope of the project of constructing a UAV which will possess the capabilities of both helicopter
and airplane. Many reasons to this purpose , most important being because this branch of
aerospace industry has not fully been succeeded. Their success is limited to jet aircraft with
VTOL which use thrust vectoring and helicopters which use cyclic pitch and collective pitch to
hover.
9
The success of this model could be a breakthrough for larger scale models and eventually there
could be a new era of transportation where the private, military aircrafts could also implement
this concept an use shorter runway for take-‐off and cruise at a higher speed.
One of the main advantages of this type of aircraft is that if in case the engine fails, the aircraft
can glide and land as a normal aircraft since it has wings to create lift unlike helicopter, similarly
vice versa.
10
Parametric Study The aircrafts made with the similar concept is taken into this parametric study
RC TWIN VTOL PROTOTYPE
Figure 2
Specifications and details
Dimensions
Length -‐ 43 inches
Wingspan -‐ 48 inches
Center wing -‐ 29 inches
Motor spacing -‐ 19 inches
11
Specification
Motors -‐ AXI 2212/26
Propellers -‐ MPI MAXX PRODUCTS counter rotating pair 10 x 4.5 slow flyer
ESC controller -‐ Castle Creations newer phoenix 25 Amp with 3 amp BEC
Batteries tested -‐ Polypus PQ-‐2100XP-‐3S 2100ma 20 C rated 167 grams or PD-‐B2600N-‐SP 3S
2600ma 12C rates 192 grams
External mixers -‐ 2 VEE-‐TAIL OMNI mixers
Aircraft Structure -‐ 1/4 inch balsa tail and fuselage, 2 @ 8mm diameter carbon fiber tubes
C of G -‐ on the tilt spar tube of maximum 1/4 inch front of the C of G -‐30% of wing chord
position WING
Static Thrust -‐ max 1300 grams
Weight -‐ 920-‐950 grams
12
V-‐22 OSPREY MODEL
Figure 32
Specifications and details
Dimension
- Length – 38.5 inches
- Span – 36 inches
- Center wing – 22 inches
- Weight – 1500 g
Power system – 2 Scorpion HK 2221-‐10 motors
Propeller – APC 12 x 3.8 slow flyer
Servos used
- 2 HITEC HS-‐5085MG (for tilting motors)
- 2 micro servos (for controlling movable surfaces )
2. 2 2 http://www.theuav.com/
13
Structure
- Primary – Balsa wood
- Secondary – Carbon rods and aluminum pipes
Electricals
- Receiver – Futaba R617FS
- Battery – Two EM2200 4S
- ESC – Two Phoenix ICE Lite 50SB
- Gyro – Three Futaba GY401
- Receiver power – CC regulator 20A Pro
Airfoil used – NACA 2413
Wing used – Straight wing
Empennage:
Horizontal and vertical stabilizer – conventional
Adhesion
- E-‐poxy 30 minutes
- E-‐poxy 5 minutes
- Hot glue
14
Specifications and details (AERO-CHOPPER)
Dimensions
- Length – 39 inches
- Span – 34 inches
- Center wing – 22 inches
- Approximate weight estimation – 2.5 to 3 kg
Power system – two Power electric motors
Propeller – APC 12 x 3.8 slow flyer
Servos used
- 2 high torque and high speed servo (for tilting the motors)
- 4 Micro servos ( for controlling movable surfaces )
Structure
- Primarily : Balsa wood
- Secondary : Carbon rods and aluminum pipes
Electricals
- Minimum 9 channel receiver and transmitter
- Minimum 3 gyros
- 2 external V-‐mixer
- Wire extensions
- Y-‐splitters
- Two 4cell battery packs
- 1 BEC
- 2 Electronic Speed Controllers – Minimum 60amps
Airfoil used – NACA 2414
Wing used – straight single high wing with uniform chord
15
Empennage:
Horizontal and vertical stabilizer – conventional
Engine mount – is tilted inwards by 2.3degrees
Adhesion
- Z-‐poxy 30 minutes
- Z-‐poxy 5 minutes
16
Mission Objectives
• Design and construct a hybrid aircraft of a helicopter and an airplane.
• Ensuring stable takeoff, land and transition from hover mode to forward mode.
• Ensure that the aircraft has an average endurance of a minimum 15 minutes in
hover mode or normal mode.
Outcomes
• Gathering information about How VTOL mechanism works.
• The type of wings and body constructed suitable to the VTOL concept
• Defining a set of parameters that we want the plane to conform to.
• Identify the materials and the budget required.
• Mathematical and aerodynamic calculations and maneuver calculation.
• Design the aircraft in a 2D & 3D sketch on AUTOCAD.
• Create an effective launch system in hover mode.
• Experiment the prototype model & troubleshoot safety & related issues.
• A Presentation of the aircraft.
Table 1
SPECIFICATIONS
Wing span (A) Span < 1m
Type of Wing Straight wing
Weight Weight < 2kg
Fuselage Length(a) Length < 1m
17
GANTT CHART
18
19
DESIGN CONCEPT The concept of Aero-‐chopper is very simple but involves sophisticated electrical and mechanics
for it to work.
The aircraft will be a twin engine and the engines will be on both the ends of the wing and will
be placed exactly on the C.G of the aircraft so that when the thrust is given, and if the aircraft is
balanced exactly on the C.G(motors), Aero-‐chopper should lift vertically.
Figure 4
The control of Aero-‐chopper on the different axis will be done by moving the engines and also
by powering up and down of the motors.
For the control of the pitch, Aero-‐chopper will tilt its wing anti-‐clockwise which would move the
direction of the propellers too. This will cause a change in the pitch of the aircraft.
20
Figure 5
The Aero-‐chopper should also have the capability to tilt its engine forward about 45o to help it
transit from Hover mode to normal aircraft mode where its engine will be 0o (parallel to the
direction of flight)
Figure 6
21
COST ANALYSIS Man hours analysis
Table 2
WBS Sheet: 1 Analysis in hours
Activity description Est to
complete
Est @
complete
Variance
GANTT CHART 2 3 1
Research 15 20 5
Aircraft Design 25 40 15
Design Approval 3 5 2
Parametric Design 4 4 0
Airfoil selection 2 2 0
3D design 15 20 5
Mission 1 1 0
Selection of aircraft parts 3 5 2
Cost Analysis 2 2 0
Tools and Materials(separate sheet) 10 16 6
Construction plan printing/Tracing 20 23 3
Cutting of material parts and organizing 4 4 0
Construction of aircraft structure accordingly 45 55 10
Assembly made rigid and Shaping 3 4 1
22
Electricals and Servos purchase(separate sheet) 5 5 0
Custom circuit made and tested 4 5 1
Fixing of Electricals and Servos 10 13 3
Aircraft performance test 3 3 0
Performance calculations 15 20 5
Centre of Gravity placement/calculations 2 2 0
Flight Test -‐ 1 3 3 0
Painting and finishing of aircraft structure 2 2 0
Flight Test -‐ 2 3 4 1
Final Calculations 2 4 2
Flight Test -‐ 3 3 3 0
Project report writing 10 15 5
Finalization of Aircraft 1 1 0
Deliverable 2 2 0
TOTAL 219 286 67
23
MAN POWER
Table 3
Days for the Project 90 days
Days devoted to the project
70 days
Average hours worked per day
4hours/day
Total hours for the days worked
45 x 4 = 180 hours
Average Man power = no. of persons/ hours
1/180
So a person has to work for 280 hours on this project.
24
Cost analysis Table 4
WBS Sheet: 2 Analysis in costs
Activity description Est to
complete
Est @
complete
Variance
GANTT CHART 0 0 0
Research 0 30 30
Aircraft Design 50 70 20
Design Approval 50 65 15
Parametric Design 0 0 0
Airfoil selection 0 0 0
3D design 0 0 0
Mission 0 0 0
Selection of aircraft parts 0 0 0
Cost Analysis 0 0 0
Tools and Materials(separate sheet) 600 820 220
Construction plan printing/Tracing 50 85 35
Cutting of material parts and organizing 30 35 5
Construction of aircraft structure accordingly 50 60 10
Assembly made rigid and Shaping 30 30 0
25
Electricals and Servos purchase(separate sheet) 6000 7740 1740
Custom circuit made and tested 0 0 0
Fixing of Electricals and Servos 0 30 30
Aircraft performance test 0 0 0
Performance calculations 0 0 0
Centre of Gravity placement/calculations 0 0 0
Flight Test -‐ 1 200 200 0
Painting and finishing of aircraft structure 30 40 10
Flight Test -‐ 2 200 200 0
Final Calculations 0 0 0
Flight Test -‐ 3 200 200 0
Project report writing 0 0 0
Finalization of Aircraft 0 0 0
Deliverable 50 50 0
TOAL 7540 9655 2115
26
Cost of materials and electricals Table 5
Items Quantity Cost per piece(aed) Total Amount (aed)
Materials
Balsa wood pack 1 500 500
Glues 5 35 175
Sand Paper 10 5 50
Cutter 3 15 45
Monocot 1 50 50
Electricals
Propellers 3 60 180
Electric Speed Control 3 480 1440
Battery 3 640 1920
Engine(Motor) 3 460 1380
Radio unit 1 1000 1000
Landing Gear unit 1 500 500
Servo pack 4 170 680
Servo(Tilt rotor) 2 290 580
Hinges pack 3 20 60
Total 43 4225 8560
27
Materials3 Balsa wood
Figure 7
Balsa wood is the main material that we have used to construct the aircraft. Balsa wood is
lightweight, inexpensive and relatively strong. We have used it to construct the fuselage, wing
and tail-‐plane as well as in the sheeting of the plane.
Ply wood
Figure 8 We used ply wood on our model on the places where we need more strength like the root rips
of the wing, the front side cover of the fuselage, servo plates etc.
The materials that were mainly used were Balsa and Plywood
3. 3 http://www.moneysmith.net/Soaring/soaring4.html
28
Table 6
Component Material Thickness
flat fuselage sides, wing ribs, wing
spruces, main frame of fuselage,
servo holder, battery pack holder ,
frame and landing gear support area
etc.
B-‐Grain balsa wood 4 mm
Elevator ,horizontal stabilizer,
vertical stabilizer, aileron and rudder
C-‐grain balsa wood 3.2 mm
Covering rounded the fuselage,
planking fuselage and nose and wing
surface
A-‐grain 1.5 mm
To support some particular area like
inside the fuselage, Tilt roll of the
wing, and landing gear hold and
support area etc.
we used very small amount of ply
wood to make structure strong.
Plywood 4 mm
Thickness
▬ Mostly we used 4mm balsa for our main construction like wings , flat fuselage sides,
wing ribs, formers, trailing edges where more strength are required.
▬ We used 3.2 mm for body where it is not required to be very strong and it’s because to
reduce weight. we also used it for rudder, elevator, stabilizer, other attachments etc.
▬ In our project used 1.5mm where it is required for covering.
29
E-poxy Glue
Figure 9
Epoxy is a strong, important modeling glue but one which must be used sparingly because of its
heavy weight.
Epoxy is classified by its strength and working time. Quick cure, or five minute epoxy, is strong
enough for most modeling applications, and is very handy for quick repairs. Slow cure (30
minute or more) epoxy is used when extra strength is required.
We have used epoxy to join the major parts of the airplane. This includes joining the wing
mounts to the fuselage, and attaching the tail to the fuselage. We have also used slow cure
epoxy for bonding the wood skins to the foam wing and stabilizer core.
Masking Tape
Figure 10
We used masking tape for minor repairs in the airplane. Masking tape was chosen due to its
convenient size, shape and ease of removal. It was mainly used for fixing small cracks in the
balsa wood.
30
Tools
Drill tools Figure 11
We used a small hand drill to drill holes in the balsa wood. A drill press was also used to make
sure that the holes were straight. Our hand drill was able to make holes of 2mm thickness.
Protractor Figure 12
We used a protractor to measure various angles in the model aircraft, which were needed in the
calculations. For example, we used it to measure the sweptback angle and the angle of the tail
planes.
Cutter
Figure 13
31
We used a normal cutter as it was very useful to cut the balsa wood, it easily cut through the
wood and was simple to handle. We sometimes used it to file the surface of the wood to make it
smooth and even.
Rulers
Figure 14
We used rulers for measuring the dimensions of the aircraft like wingspan, length of the
fuselage etc.
Sand paper Figure 15
Sandpaper is used to remove small quantities of material at a time from the surface of an
object. Sandpaper can be used to remove a specific material from an object (such as a layer of
paint) or to level and/or smooth the surface of the object. Sandpaper comes in many numbered
"grades," with smaller numbers being coarser and removing more surface material with each
pass. Higher numbers are finer and remove less material.
We have mostly used ‘low grade’ sandpaper for polishing and smoothing the aircraft. We have
also used it to shape the ribs and spars of the model aircraft.
32
ELECTRICALS4
MOTORS
Main wing motors(2 on the either sides of the wing)
Figure 16
Power 10 Brushless Out-‐runner Motor, 1100Kv
Key Features
• Equivalent to a 10-‐size glow engine for 32–48 ounce (910–1360 g) airplanes
• Ideal for 3D airplanes weighing 28–36 ounces (790–1020 g)
• Ideal for models requiring up to 450 watts of power
• High-‐torque, direct-‐drive alternative to in-‐runner brushless motors
• Includes mount, prop adapters and mounting hardware
• External rotor design—5mm shaft can easily be reversed for alternative motor
installations
• Slotted 14-‐pole out-‐runner design
4. www.e-‐fliterc.com/Products
33
• High-‐quality construction with ball bearings and hardened steel shaft
• Quiet, lightweight operation
Overview
The Power 10 is designed to deliver clean and quiet power for 10-‐size sport and scale airplanes
weighing 32 to 48 ounces (910 to 1360 grams), 3D airplanes weighing 28 to 36 ounces (790 to
1020 grams), or models requiring up to 375 watts of power. It’s an especially good match for the
E-‐flite Brio 10 for high speed F3A precision or artistic aerobatics.
Product Specifications
Type: Brushless out-‐runner motor
Size: 10-‐size
Bearings or Bushings: One 5 x 14 x 5mm Bearing, and One 5 x 11 x 5mm Bearing
Wire Gauge: 16
Recommended Prop Range: 10x5–12x6
Voltage: 7.2–12
RPM/Volt (Kv): 1100
Resistance (Ri): .043 ohms
Idle Current (Io): 2.10A @10V
Continuous Current: 32A
Maximum Burst Current: 42A (15 sec)
Cells: 6–10 Ni-‐MH/Ni-‐Cd or 2–3S Li-‐Po
Speed Control: 35–40A brushless
Weight: 122 g (4.3 oz)
34
Overall Diameter: 35mm (1.40 in)
Shaft Diameter: 5mm (.20 in)
Overall Length: 43mm (1.60 in)
Needed to Complete
E-‐flite Brio 10
40A ESC
6-‐ to 10-‐cell Ni-‐MH/Ni-‐Cd or 2–3S Li-‐Po
10x5 to 12x6 electric props
Tail Wing motor(1 at the rear)
Figure 17
Park 370 BL Outrunner,1200Kv with 4mm Hollow Shaft
Key Features
• Ideal for models requiring up to 120 watts of power
• Optimized windings for 3D performance
35
• High-‐torque, direct-‐drive alternative to in-‐runner brushless motors
• Includes mount, prop adapters and mounting hardware
• 4mm hollow shaft is easily reversed for alternative motor installations
• Excellent motor for small 3D airplanes 7–14 oz (200–400 g)
• Extremely lightweight—just 1.6 ounces
• Ideal for variable pitch props such as the E-‐flite® Showstopper Variable Pitch
Prop System
• External rotor design for better cooling
• High-‐quality construction with ball bearings
Overview
E-‐flite’s latest Park 370 is a brushless out-‐runner motor that features a 4mm hollow shaft, ideal
for use with variable pitch propellers. It’s perfectly designed for electric models equipped with
variable-‐pitch propeller systems, such as the E-‐flite® ShowStopper VPP system. However, you
don’t need a VPP to use this motor—it’s an excellent motor for small 3D airplanes that weigh 7–
14 ounces. A motor mount, prop adapter and all hardware are included.
Product Specifications
Type: Brushless out-‐runner
Size: Park 370
Bearings or Bushings: One 4 x 8 x 4mm Bearing, and One 4 x 9 x 4mm Bearing
Recommended Prop Range: 8x3.8–10x4.7 or Variable Pitch systems
Voltage: 7.2–12V
RPM/Volt (Kv): 1200
Resistance (Ri): .18 ohms
Idle Current (Io): .60A
36
Continuous Current: 10A
Maximum Burst Current: 12A (15 sec)
Cells: 6–10 Ni-‐MH/Ni-‐Cd or 2–3S Li-‐Po
Speed Control: 12–20A Brushless
Weight: 45 g (1.6 oz)
Overall Diameter: 28mm (1.10 in)
Shaft Diameter: 4mm (.16 in) hollow
Overall Length: 25mm (1.00 in)
Needed to Complete
12–20A brushless ESC
2–3S Li-‐Po or 6–10 Ni-‐Cd/Ni-‐MH
8x3.8–10x4.7 Slow Flyer Prop
Variable Pitch Prop option
37
ELECTRONIC SPEED CONTROLLER
ESC Eletronic Speed Control Detrum 30-‐40a 2-‐6s LIXX / 5-‐18s NC -‐ 0km
Model: E
Figure 18
• Model: ESC-‐40A
• Size(mm): 50 X 25 X 13
• Weight: 36g
• Current:40A
• NiCd/NiMh] /servos: 6/5 8/5 10/4 12/3
• [Li-‐xx]/servos: 2/5 3/4
38
BATTERY
Esky EK1-‐0186 20C 11.1v 1800mah Li-‐Polymer battery
Figure 19
Product Description
Table 7
Item NO. EK1-‐0186
Size 100*34*25mm
Weight(g) 47.0ï؟½ï 5.0½؟
(single electric core)
discharge magnification 20C
compages form connection in series
charging port XH2.5-‐4P reversal
(equilibrium charge)
Inner resistance 20mï؟½ï؟½ max
(single electric core)
discharging cut-‐off voltage 2.75V
(single electric core)
charging cut-‐off voltage 4.20ï؟½ï 0.05½؟ V
(single electric core)
long-‐time load voltage 3.6V~4.1V
(single electric core)
39
Radio
JR Propo DSX7 7-‐Channel 2.4GHz Computer Radio Control System (DSMJ), Package includes
Transmitter 2.4GHz DSMJ, RD731 7Ch 2.4G DSMJ Receiver w/EA131 Remote Receiver, ES539
Standard Servo x3, TX 8N 1500mah Ni-‐MH battery, Switch and 220V charger. English manual
included. | Mode 1, Mode 2 inter-‐changeable.
Figure 20
Product Code : [DSX7 2.4G DSMJ w/ES539 [DSX7JES539]]
Quality product from JR Propo.
JR Propo -‐ 2.4GHz Spread Spectrum Technology (DSMJ)
JR Propo DSX7 2.4GHz Computer Radio Control System (DSMJ) is suitable for Beginner to
Intermediate flyers and also the only model for even the advanced. It is reliable and stable with
2.4GHz with built-‐in system, promising an exciting flight in the comfort of all flyers.
It comes with Transmitter 2.4GHz, RD731 2.4GHz DSMJ 7 Channel Receiver w/EA131 remote
receiver, 3pcs x ES539 standard servos for electric model or glow model use.
The system comes with Mode 1 which can be changed to Mode 2 by editing system software
with stick spring.
The Flight Mode is at the right hand side.
40
Content
JR Propo DSX7 Transmitter 2.4GHz DSMJ
RD731 7Ch 2.4GHz DSMJ Receiver w/EA131 Remote Receiver
JR04884 2.4GHz Remote wire extension (150mm/6")
JR ES539 Standard Analog Servo x 3pcs (Servo Horns & mounting accessories included)
TX 8N 1500mah Ni-‐MH battery
NEC-‐322 220V Tx & Rx charger
Bind Plug Set
Switch
2mm Allen Wrench
English manual included | Mode 1 or Mode 2 inter-‐changeable.
Spec
-‐Method: DSMJ / Computer Mixing
-‐Number of Channels: 7ch
-‐Transmitter Weight: 640g (excluding battery)
-‐Battery fit: 8N1500
-‐For Helicopters or Airplane
Features
Band: 2.4 GHz
Servos: ES539 X 3
Receiver: RD731 (DSMJ)
Transmitter (Tx) Battery Type: 1500mah Ni-‐MH
AC: 220V
20-‐model memory
Airplane and Heli software
Switch assignment
P-‐mixes
41
3-‐axis dual rate and expo
3-‐position flap (Airplane)
5-‐point throttle & pitch curve (Heli)
3 flight modes plus hold (Heli)
Gyro programming (Heli)
CCPM swash mixing 90/120/180 degree (CCPM: Cyclic Collective Pitch Mixing System)
English manual
ES539 Standard Analog Servo Specification
Torque: 4.8kg.cm (66.67oz.in)
Speed: 0.23S/60°
Size: 32.5 x 19 x 38.5mm (1.28x0.75x1.52in)
Weight: 38g (1.34oz)
42
Airfoil Selection5 Airfoil used – NACA 2414
As this airfoil seems to be the most suited for this application according to the study shown
below
Comparing the airfoils; NACA 2412, NACA2414, NACA 2414
Naca-‐2412
Thickness: 12.0% Max CL angle: 15.0
Camber: 2.0% Max L/D: 50.702
Trailing edge
angle: 14.5o Max L/D angle:
5.5
Lower flatness: 45.2% Max L/D CL: 0.927
Leading edge
radius: 1.7% Stall angle:
7.0
Max CL: 1.204 Zero-‐lift angle: -‐2.0
5. 5 http://www.worldofkrauss.com/foils
Figure 21
43
Figure 22
NACA 2414
Figure 23
Thickness: 14.0%
Camber: 2.0%
Trailing edge
angle: 17.8o
Lower flatness: 50.5%
Leading edge
radius: 3.0%
Max CL: 1.245
Max CL angle: 10.5
Max L/D: 41.542
Max L/D angle: 6.0
Max L/D CL: 0.943
Stall angle: 10.5
Zero-‐lift angle: -‐2.0
44
NACA 2415
Figure 25
Thickness: 15.0%
Camber: 2.0%
Trailing edge angle: 19.1o
Lower flatness: 43.6%
Leading edge radius: 3.3%
Max CL: 1.281
Max CL angle: 11.5
Max L/D: 40.672
Max L/D angle: 6.5
Max L/D CL: 0.991
Stall angle: 11.5
Zero-‐lift angle: -‐2.0
45
Figure 26
From the above figures NACA 2414 is the most suitable.
NACA 2414 is selected since it has good enough thickness to accommodate 1 cm rod for the
engine tilting mechanism.
46
Ribs shapes generated with the help of the software "profili"
Figure 27
47
AIRCRAFT DESIGN The 2-‐D drawing that guided through the dimensions and construction process showing the 3-‐
isometric views of the aircraft.
Top view
Figure 28
48
Side view
Figure 29
Front view
Figure 30
49
Structure designing :(PROFILI) Wing structure with ribs placements designed with the help of Profilli
Figure 31
50
Figure 32
Figure 33
51
Rib structure Design on AutoCAD
Wing with ribs placement
52
Fuselage ribs and wing ribs placement
Spars supporting the ribs
Total structure of the wing
Fuselage ribs for support of the structure
53
54
3D Drawing Side view
Figure 34
Bottom view
Figure 35
55
Top view
Figure 36
56
Circuits
Tilt rotor circuit
Figure 37 Figure 38
Tilt rotor mechanism
Figure 39 Figure 40
57
Servo circuit
Figure 41
58
CONSTRUCTION (ASSEMBLY)
Figure 42
The Design(plan) gave us a green signal to finally start with the construction of the aircraft. The
component parts that were needed to form an assembled aircraft were each traced and draw
on the balsa wood with the respective dimensions using the carbon paper. These designs of the
parts were traced with the help of a transparent paper.
59
Figure 43
And then all the shapes were cut with the help of a normal metal cutter, and then placed
separately.
Figure 44
60
Starting with the wing, which had the following units:
• 8 airfoil shaped ribs each wing.
• 3 spars
• Tilt rotor holder ribs
Figure 45 Figure 46
Figure 47
61
Holes made with the help of a small drilling machine done by a professional. Holes made for the
space provision of the spars going through the airfoil parts.
Figure 48
Wing placed according to the design with the spars going through them making the entire inner
structure of the wing.
62
Fuselage
Figure 49
The Fuselage ribs cut accordingly and shaped as per the design.
Figure 50
Figure 51 Figure 52
63
Figure 53
Spaces at the sides of the fuselage ribs provided for placement of the support balsa sticks
making the fuselage structure rigid.
Figure 54
The fuselage ribs placed accordingly at correct distances as per the design.
Long balsa sticks glued to the spaces provided at the sides of the fuselage ribs.
64
Figure 55
Figure 56
The center part of the wing where it is placed on top of the fuselage structure, is constructed
accordingly for the holding of the tilt rotor mechanism parts.
65
Figure 57
Ply wood used for the support of the wing structure against the fuselage to give the area a
better rigidness and support, and a free movement in direction for the wing.
Figure 58
Landing gear support is constructed at the lower part of the fuselage on the either sides, so as to
give the landing gear a space away from the main fuselage structure.
66
Engine Mount
Figure 59
The engines placed on the either sides of the wing must be supported very strong as high stress
is faced in this area due to maximum throttle of the motor.
This area is mounted with balsa and ply wood together giving it a very good hold preventing
from breaking due to stress.
Figure 60
67
Tail wing
Figure 61
The tail-‐wing includes the horizontal stabilizer , the rudder and the tail motor mount.
Figure 62
Parts of the tail wing placed and fixed accordingly forming the internal structure of the
horizontal stabilizer and the rudder.
68
Figure 63
The total internal structure is constructed.
Figure 64
Figure 65
69
Tilt-Rotor mechanism structure
The tilt rotor section, constructed accordingly with the provision of the spar going through the
whole wing and the strong support for the tilt rotor mechanism structures.
Figure 66 Figure 67
Figure 68 Figure 69
70
Figure 70
Wing at the tilt position for the hovering part of flight
Electricals and servos fixed at the appropriate locations
Figure 71 Figure 72
71
Tail-‐motor fixed with the mount supporting it and giving the propeller blades a clearance
distance from the tail wing.
Figure 73
Figure 74 Figure 75
Landing gear attached, one on either sides and one at the tail-‐part of the fuselage
Figure 76
72
Battery holder is made by creating a space exactly measured for the battery to fit it.
Figure 77
Motors fixed to the mounts on the either side of the wings.
Figure 78
73
Tilt-‐Rotor Aircraft sheeting, shaped and painted.
Figure 79
Aero-‐chopper presented with the Tilt-‐rotor function.
Figure 80
74
GRAPHS6 The graphs that we are going to use are the following
The aerodynamic form factor graph
Figure 81
6. 6 Fundamentals of Flight by Richard S Shovel
75
Figure 82
Figure 837
76
Figure 84
Figure 85
77
Table 8
78
Area Calculation CALCULATIONS:
Wing
Drawing 1
Drawing 2
Rectangle
Area = l x b
= 35 x 18 = 648cm2
RIGHT + LEFT = 648 + 648 = 1296cm2
79
Drawing 3
Rectangle
Area = l x b
= 13.5 x 9.1 = 122.85cm2
Total wing area(TOP) = Left section + Right section + Center section
= 648 + 648 + 122.85
= 1418.85cm2
Total wing area(BOTTOM) = Total wing area(TOP)
Total Wing Area(TOP and BOTTOM) = TOP + BOTTOM
= 1418.85cm2 + 1418.85cm2
= 2837.7cm2
Airfoil shaped side section of wing
With the help of AutoCAD the exact area of the side section of the wing could be taken by
calculating the area of the airfoil.
80
Drawing 5
Area = 4.1455inch2 = 26.745cm2
2 sides = 26.745cm2 x 2 = 53.49cm2
Area of the sides view of the wing = 53.49cm2
Total surface Area of the Wing = Side-‐view Area + Top & Bottom view Area
= 53.49cm2 + 2837.7cm2
= 2891.19cm2
Total Surface Area of the Wing(MAIN) = 2891.19cm2
Drawing 4
81
Horizontal Stabilizer
Drawing 6
Rectangle
Area = l x b = 7.5 x 12.2 = 91.5cm2
Triangle
Area = 1/2 b h = 1/2 x 4.5 x 12.2 = 27.45cm2
Total = Rectangle + Triangle = 27.45 + 91.5 = 118.95cm2
2 sides = 118.95 + 118.95 = 237.9cm2
82
Vertical Stabilizer
Drawing 7
Rectangle
Area = l x b = 52 x 10 = 520cm2
Top and bottom = 520 x 2 = 1040cm2
Total Area = 1040cm2
Engine Mount
Drawing 8
l = 11.7cm
83
w = 5.1cm
h = 5.1cm
Area of cuboid = 2 ( lw + wh + hl )
= 2 ( 11.7x5.1 + 5.1x5.1 + 5.1x11.6 )
= 2 (145.35) = 290.7cm2
Total Area of Engine Mount(2 sides) = 290.7cm2 x 2 = 581.14cm2
Engine Mount(TAIL)
Drawing 9
l = 11.5cm , w = 3.8cm , h = 2cm
Area of cuboid = 2 ( lw + wh + hl )
= 2 ( 11.5x3.8 + 3.8x2 + 11.5x2 )
= 2( 74.3 ) = 148.6cm2
Total Area of Engine Mount(TAIL) 148.6cm2
84
Fins
Drawing 10
Triangle
Area = 1/2 b h = 1/2 x 4.9 x 6.8 = 1/2 x 33.32 = 16.66cm2
Rectangle(R1)
Area = l x b = 6.8 x 5 = 34cm2
Rectangle(R2)
Area = l x b = 9.9 x 2 =19.8cm2
Total Area(one side-‐one fin)=Triangle + R1 + R2 = 16.66 + 34 + 19.8 = 70.46cm2
2 Sides = 70.46 x 2 = 140.92cm2 ; 2 Fins = 140.92 x 2 = 281.84cm2
Total Area of the fins = 281.84cm2
85
Landing Gear Hold
Drawing 11
Airfoil area -‐ 2.7910cm2 = Side surface
53.49 -‐ 2.7910 = 50.699
Area = 50.699cm2
Forward section
Drawing 12
Area = l x b = 7.5 x 2 = 15cm2
86
Top and Bottom surface
Drawing 13
Area = l x b = 7.5 x 16 = 120cm2
Top and bottom = 120 x 2 = 240cm2
Total Landing gear hold Area = Side + Forward + Top and Bottom
= 50.699 + 240 +15
= 305.699cm2
87
Area of Fuselage
Drawing 14
Area of the fuselage side section
= Area A + Area B +Area C + Area D + Area E + Area F
Area A
(Trapezium)
Drawing 15
Area of Trapezium = (a + b)/2 x h
= (5 + 6.3)/2 x 2.9 = 16.385cm2
88
Area B
Drawing 16
Area of Trapezium = (a + b)/2 x h
= (6.3 + 8.5)/2 x 4 = 29.6cm2
Area C
Drawing 17
Rectangle
Area = l x b = 56.95cm2
Triangle
Area = 1/2 x b x h = 1/2 x 4.6 x 6.7 = 15.41cm2
Total Area = 56.95 + 15.41 = 72.36cm2
89
D
Drawing 19
Can be assumed as:
Area = l x b = 13.4 x 16.5 =
221.1cm2
E
Drawing 20
Drawing 18
90
Rectangle
Area = l x b = 7.8 x 23.2 = 180.96cm2
Triangle
Area = 1/2 x b x h = 1/2 x 5.9 x 23.2 = 249.4cm2
F
Drawing 21
Area = 1/2 x b x h = 1/2 x 7.8 x 24.3 = 94.77cm2
Total Area of Fuselage Side section = A + B + C + D + E + F
= 16.385 29.6 + 72.36 + 221.1 + 249.4 + 94.77 = 683.615cm2
Both sides = 683.615 + 683.615
= 1,367.23cm2
91
Fuselage(TOP AND BOTTOM)
Drawing 22
92
A'
Drawing 23
Area of trapezium
= ( a + b )/2 x h = ( 6.2 + 12.1 )/2 x 6
= 225.06cm2
B'
Drawing 24
Area of Trapezium
= ( a + b )/2 x h = ( 12.1 + 13 ) / 2 x 7.6
= 95.38cm2
93
C'
Drawing 25
Area = l x b = 13 x 10
= 130cm2
D'
Drawing 26
Area = l x b = 8.2 x 5.5 = 45.1cm2
94
E'
Drawing 27
Area = l x b = 13 x 29.4 = 382.2cm2
F'
Drawing 28
Area = 1/2 x b x h
= 1/2 x 13 x 24 = 156cm2
95
Total Area of Fuselage(TOP)
Area A' + B' + C' + D' + E' + F' = Total Area
225.06 95.38 + 130 + 45.1 + 382.2 + 156 = 1,033.74cm2
TOP and BOTTOM = 1033.74 x 2 2067.48cm2
Front surface
Drawing 29
Area = l x b = 6.2 x 5 = 31cm2
Total Area of Fuselage
SIDES + TOP/BOTTOM + FRONT
= 1367.23 + 2067.48
= 3465.71cm2
Total Area of Fuselage = 3465.71cm2
Total Area of Wing = 2891.19cm2
Total Area of Tailing = 1040cm2
Total Area of Horizontal Stabilizer = 237.9cm2
96
Total Area of Fins = 281.84cm2
Total Area of Engine Mounts(MAIN) = 581.14cm2
Total Area of Engine mount(TAIL) = 148.6cm2
Total Area of Landing Gear Hold = 305.699cm2
TOTAL SURFACE AREA OF THE AIRCRAFT =
Fuselage + Wing + Tailing + Horizontal Stabilizer + Fins + Engine Mounts(MAIN) + Engine
mount(TAIL) + Landing Gear Hold
= 3465.71cm2 + 2891.19cm2 + 1040cm2 + 237.9cm2 + 281.84cm2 + 581.14cm2 + 148.6cm2 +
305.699cm2
Total Surface Area of the Aircraft = 8952.079cm2
97
PERFORMANCE ANALYSIS LIFT
Airfoil used is NACA 2414
The software profili gives us the following values;
CLmax = 1.379 at 15o AOA
CL = 0.752 at 4o AOA
During cruise
Considering the angle of attack of wing, during cruising will be 40.
We know that L = W during cruise.
L = 2 KG
L = 20 N
Ρ(density) at sea level = 1.225 kg/ m3
S(wing area) = 0.05898m2
L = 1/2 P CL V2 S Eq (1)
V2 = 2L / ρ CL S = 2 * 20 / 1.225 * 0.752 * 0.05898
V2 = 737.2
V = 27.15m/s
98
During Landing
The Cl is at max = 1.379
V2 = 2L / ρ CL S = 2 * 20 / 1.225 * 1.379 * 0.0589
V2 = 409.50
V = 20.2 m/s
99
Vstall is the lowest speed at which steady controllable flight can be maintained any further
increase in AOA will cause flow separation on the wing upper surface, a drop in lift, a large
increase in drag. In a well-‐designed airplane, a strong pitch-‐down moment is experienced.
Vstall = Vat landing
Vstall = 20.2 m/s
LIFT during landing
L = 1/2 P CL V2 S Eq (1)
= 1/2 *1.225* 1.379*20.22 * 0.05898
L = 20.2 N
During take off
Velocity at take-‐off is 20% greater than Vstall.
VTO = 20.2 + 20.2 x 0.20
= 24.24 m/s
100
OR
Around 70% of CLMAX
i.e. 0.70x1.379 = 0.966
VTO2 = 2L / ρ CL S = 2 * 20 / 1.225 * 0.966 * 0.05898
i.e. At 60 AOA VTO = 23.9 m/s
LIFT during Take-off
LTO = 1/2 P CL V2 S Eq (1) [since CL = 0.966
= 1/2 *1.225* 0.966*20.22 * 0.05898 and VTO = 21.8]
LTO = 14.43N
DRAG
The total Drag of the Aircraft is calculated by summing the parasite and induced drag together.
101
CD = CDP + CDi
D = CDqS
Drag is calculated for three phase of flight i.e. Take off, Cruise and landing.
At Take Off
CDptotal is calculated by computing CDp for wing, fuselage , horizontal and vertical stabilizer
separately.
CDp of wing
∑ 𝐾𝐶fswet / Sref Eq (4)
Sref = 0.028912m3
Swet = 0.05898 m3
Cr = 0.18 m
CT = 0.18 m
σ = CT / Cr = 1
L = MAC Eq (5)
= 2/3 x Cr (1 + σ -‐ σ/(1 + σ) )
= 2/3 * 0.18 ( 1 + 1 -‐ 1/(1 + 1)) = 2/3 *0.18(2 -‐ 1/2)
= 0.18
L = 0.18
102
V = 1.4607 * 10-5
RN = V0 x L/v Eq (6)
= 24.24 * 0.18 / 1.4607 * 10-‐5
RN = 298,706.0998
Since RN > 200,000
The flow is turbulent
Cf for turbulent
Cf = 0.455 / [(log10RN)2.58 = 0.455 / [log10298,706.0998) 2.58
= 5.6 x 10-‐3 Eq (7)
103
From fig 9c.1 we get K = 1.265
Hence CDp = ∑ 𝐾𝐶fswet / Sref Eq (4)
= 1.265 x 5.6 x 10-‐3 x 0.05898 / 0.028912
CDpwing = 0.01443
104
CDp of fuselage
Fuselage Area = 0.3465 m2
Fuselage length = 1.016 m
RN = ( Vo * L)/v Eq (6)
= (24.24 * 1.016)/ 1.4607 x 10-‐5 = 1,686,029.986
RN = 1,686,029.986 > 200,000 hence the flow is turbulent
Cf = 0.455 / [(log10RN)2.58 Eq (7)
Cf = 4.062 x 10-‐3
CDpfuselage = ∑ 𝐾𝐶fswet / Sref
K from fig 9c.2
K = 1.16
105
CDpfuselage = 9.599 x 10-‐3
= 0.00959
CDp of Horizontal Stabilizer
H.S of Area = 0.02379m2
106
Cr = 0.12 m
Ct = 0.075 m
σ = CT / Cr = 0.625
t/c = =
Swet = 0.0485
Sref = 0.02379
L = MAC
= 2/3 x Cr (1 + σ -‐ σ/(1 + σ) )
= 2/3 x 0.12 ( 1 + 0.625 -‐ 0.625/(1+0.625) ) = 2/3 x 0.12 ( 1.625 -‐ 0.3846)
L = 0.0992
RN = V0 x L / v
= 24.24 x 0.0992 / 1.4607 x 10-‐5 =
as 164,620.25 > 200,000
Hence flow is laminar
Cf = 1.328 / √RN Eq (7)
= 3.27 x 10-‐3
K from fig 9c.1
K = 1.155
CDp = ∑ 𝐾𝐶fswet / Sref
= 1.155 x 3.27 x 10-‐3 x 0.0485/0.02379
107
CDp H.S = 0.00767
108
CDp of Vertical Stabilizer
Area of Vertical Stabilizer = 0.01040
Cr = 0.1 m
Ct = 0.1 m
σ = CT / Cr = 1 m
Swet = 0.021216
Sref = 0.0104
t/c = =
L = MAC
= 2/3 x Cr (1 + σ -‐ σ/(1 + σ) )
= 2/3 x 0.1 (1 + 1 -‐ 1/(1 + 1) = 2/3 x 0.1 (2 -‐ 1/2)
L = 0.1 m
RN = V0 x L / v Eq (6)
= 24.24x 0.1 / 1.460 x 10-‐5
= 166,027.397 < 200,000
Cf for Laminar Boundary layer
Cf = 1.328 / √RN Eq(8)
= 1.328 / √166,027.397
= 3.25 x 10-‐3
K from fig 9c.1
K = 1.185
109
CDp = ∑ 𝐾𝐶fswet / Sref Eq(4)
= 1.185 x 3.25 x 10-‐3 x 0.021216/0.0104
CDp V.S = 7.85 x 10-‐3
110
Total CDp for the Aero-‐chopper during Take-‐Off
111
CDptotal = CDpwing + CDpfuse + CDp H.S + CDp V.S
= 0.01443 + 0.0095 + 0.00767 + 0.00785
CDptotal = 0.03945
Induced Drag CDi
CDi = CL2/πARe
AR = b2 / s = 0.862 m / 0.028912 m2
= 2.5581
Cl at Take-‐Off = 0.966
(constant) U = 0.99
(constant) S = 0.975
K = 0.38 x CDptotal = 0.38 x 0.03945 = 0.014991
e = 1 / (πARK) + 1 / u + s
= 1 / (π x 2.558 x 0.01499 ) + 1/(0.99 + 0.975)
112
e = 8.8135
CDi = (0.966)2 / (π x 2.55 x 0.933)
= 0.124
The total efficient of drag is
CDptotal = CDp + CDi
= 0.03945 + 0.124
CDptotal = 0.1642
113
114
DRAG total
D = CDPV2S / 2
= (0.1642 x 1.225 x 24.242 x 0.0589) / 2
D = 3.48N
L/D Ratio during Take-‐off = 14.43 / 3.48 N
= 4.14 N
Wing loading = W / S = 2 / 0.028912 = 69.17 kg/m2
Thrust to Weight ratio = T / W = 4 / 2 = 2
115
116
AIRCRAFT MANEUVERS
Turning Performance
V = 27.1 m/s
θ = 60o
g = 10 m/s 2
n = 1/Cosθ = 1/Cos60 = 2
Level Turn
Radius of turn (r)
r = V2/g√n2 – 1) = 27.12/10√(22 -‐1) = 27.12/10√3 = 42.4m
Angular Velocity (ω)
ω= g√n 2 – 1/v = 10 * √3/27.1 = 0.63 m/s
117
Vertical Turn Pull up
Radius of turn (r)
r = r 2/g(n-‐1) = 27.1 2/10(2-‐1) = 73 m
Angular velocity
ω= g(n-‐1)/v = 10(2-‐1)/27.1 = 0.36 m/s
VERTICAL TURN PULL DOWN
Radius of turn (r)
r= v 2/g(n+1) = 27.12 /10(2+1) = 24m
Angular velocity
ω = g(n +1)/v = 10* 3/27.1 = 1.1 m/sθ
Vertical turn
Radius of turn r
r = v2/gn = 27.12/10*2 = 36 m
Angular velocity (ω)
ω= gn/v = 10 * 2/27.1 = 0.73 m/s
118
HELICOPTER PERFORMANCE
Hover
Figure 86
Disc Area = A
A = π * 0.1552
= π * 0.0240
A = 0.075 m2
Density at sea level ρ = 1.2550 kg/m3
Assuming V∞ = 7 m/s
Upstream or Downstream Velocity = V∞
Induced Velocity = Vi
∆P = 1* ρ * V∞* V∞ / 2
∆P = 1x1.2250x7x7 / 2
119
= 60/2
∆P = 30 kg/m3
Thrust required to Hover
∆P = Thrust / Area
Thrust = ∆P * Area
= 30 x 0.075
Thrust = 2.25 kg/s
Since Aero-‐chopper has two motors on the either side of the main wing the total thrust is 2.25
+ 2.25 = 4.5kg/s
Velocity required to Hover
Vi = √(T/2*ρ*A)
120
= √(W / 2 * ρ where, W( Disc Loading ) = T / A
= √ 30/ (2x1.225) = 4.5 /( 2 x 0.075 )
= 30kg/m3
Vi = 3.49 m/s
121
Power required to Hover
Pi = T * Vi
= 2.25 x 3.49
P = 7.87kgm/s2
The total power required by both the motors is P * 2 = 7.87 x 2
Ptotal = 15.74kgm/s2
122
Vertical Climb
Figure 87
Rate of climb = VC
Assuming the VC = 1m/s
Vh2 = (VC + Vi) Vi
( 3.49 )2 = (1 + 0.5V) x 0.5V
12.18 = 0.5V + 0.25V2
0.25V2 + 0.5V -‐ 12.18 = 0
V = 6.05 m/s
Vi = 0.50 *V
Vi = 0.5 x 6.05 = 3.025
= 3.025 m/s
Total Velocity for Climbing = ( VC + Vi )
= ( 1 + 3.025 )
Total Velocity for Climbing = 4.025m/s
123
Thrust required for vertical climb
T = 2 ρA(VC + Vi) Vi
= 2 x 1.2550 x 0.075 x 4.025 x 3.025
T = 2.29kg/s
Total thrust required is T*2 = 4.58kgm/s2
Power required for Vertical climb
Pi = T(VC + Vi)
Pi = 2.29 ( 4.025 )
Pi = 9.21kgm/s2
Total power required is
Pi = T(VC + Vi)
Pi = 4.58 ( 4.025 )
Pi = 18.43kgm/s2
As we know the relationship between induced velocity in hover and vertical climb, the induced
velocity decreases as the climbing speed and similarly induced power increases with the
increase in climb speed.
124
Comparing the Hover and the Vertical Climb, we get.
Vertical Descend
With a flow pattern as in fig simple momentum theory gives a reasonable approximation: thus
with VC negative and Vi positive the thrust is
T = -‐2 ρA(VC + Vi) Vi
Assuming the Descend rate to be VC = -‐1m/s
T/ -‐2 ρA = (VC + Vi) Vi We know, thrust = 4.5kg
4.5 / -‐2 x 1.255 x 2 x 0.075 = (VC + Vi) Vi
-‐11.9 = (-‐1 + Vi) Vi
-‐11.9 = -‐ Vi + Vi2
Vi2 -‐ Vi -‐ 11.9 = 0
Vi = -‐2.98 m/s
And hence V∞ = -‐2 x V1
V∞ = 5.96m/s
125
Maneuvers in Helicopter Mode8
Aero-‐chopper , has 4 basic Maneuver's or has to be controlled on all the 3 axis of stability and
also on the attitude or vertical ascend;
Figure 88
• Increasing and Decreasing altitude
This is achieved by the increasing or decreasing the throttle and thereby changing the RPM
and thrust produced by the two motors which are placed on the wing tips. For Vertical
takeoff the max thrust produced by both the engines are 4 kg i.e. N whose vector
component are Vertical.
• For controlling the pitch i.e. longitudinal axis.
Since the motors are placed on the C.G. line when both the motors are tilted front or back
this aircraft is effected on its pitch axis thereby causing the aircraft to pitch up or down.
7. 8 Basic Helicopter Aerodynamics by J.Seddon
126
Figure 89
Endurance calculation
For instance an RC LiPo battery that is rated at 2000mAh would be completely discharged in one
hour with a 2000 milliamp load placed on it.
Since the motor POWER10 has been chosen it requires Electronic speed controller at
"40"amps with power supply from a battery of 1800mAh
1800mAh/ 4000 ma x 60 = 2.7 mins
= 2.7 mins
When the motor is on full throttle for 27 min the battery will drain. But this calculation is not
for completely draining the battery. The battery actually drains out after 1.5 times the
calculated time. This margin is a safety margin for avoiding the aircraft to crash because of loss
of power.
So the actual Endurance for hover is 4.05 mins
Now for normal flight the endurance is
1800mAh/ 4000 ma x 60 x 1.5 = 4.05 mins
= 4.05 mins
2.7mins of safe flight and the actual endurance for normal flying is 4.05mins
127
Range Calculation
Range is calculated by using a very simple calculation.
Range of Aero-‐chopper when it is in helicopter mode
Range = Endurance * Cruise velocity
Range = 243 sec * 27.15 m/s
= 6002.1 m
Range of Aero-‐chopper when it is in aircraft mode
Range = Endurance * Cruise velocity
Range = 342 sec * 27.15 m/s
= 8447.4 m
128
CENTRE OF GRAVITY LONGITUDINAL AXIS -‐ DATUM point is the Tip of the nose
Components Weight (gm) Distance (cm) Moment
(gm*cm)
Right ESC 60 34 2040
Left ESC 60 34 2040
Wing tilt servo 64 28 2432
Left wing aileron servo 23 35 805
Right wing aileron servo 23 35 805
Left Tailing aileron servo 20 68 1360
Right Tailing aileron servo 20 68 1360
Receiver + Electricals 60 27 1620
Nose 31 7 217
Vertical Stabilizer 15 76 1140
Rudder 15 78 1170
Left wing aileron 10 45 450
Right wing aileron 10 45 450
Fuselage 342 45 15,390
Wing 288 32 9,216
Main Landing gear(Right) 30 25 750
Main Landing gear(Left) 30 25 750
Battery pack 480 14 6,720
Left motor with mount 122 + 40 33 5,346
Right motor with mount 122 + 40 33 5,346
Tail motor with mount 50 + 40 100 9000
Monocot 5 0.1 0.5
Total 2011 68,407.5
Longitudinal Axis C.G = Total Moments / Total weight
= 68407.5 / 2011 = 34cm from the Datum point
129
LATERAL AXIS -‐ DATUM point is the Tip of the Right Engine
Components Weight (gm) Distance (cm) Moment
(gm*cm)
Right ESC 60 23 1380
Left ESC 60 51 3060
Wing tilt servo 64 30 1920
Left wing aileron servo 23 55 1265
Right wing aileron servo 23 19.5 448.5
Left Tailing aileron servo 20 75 1500
Right Tailing aileron servo 20 68 1360
Receiver + Electricals 60 34 2040
Nose 31 29 899
Vertical Stabilizer 15 72 1080
Rudder 15 74 1110
Left wing aileron 10 62 620
Right wing aileron 10 27 270
Fuselage 342 37 12,654
Wing 288 33.5 9,648
Main Landing gear(Right) 30 20 600
Main Landing gear(Left) 30 45 1350
Battery pack 480 28 13,440
Left motor with mount 122 + 40 57 9,234
Right motor with mount 122 + 40 12 1944
Tail motor with mount 50 + 40 89 8010
Monocot 5 0 0
Total 2011 73,832.5
Lateral Axis C.G = Total Moments / Total weight
= 73832.5 / 2011 = 36.7cm from the Datum point
130
DIRECTIONAL AXIS -‐ DATUM point is the mid-‐point of the Landing Gears separation
Components Weight (gm) Distance (cm) Moment
(gm*cm)
Right ESC 60 34 2040
Left ESC 60 34 2040
Wing tilt servo 64 16 1024
Left wing aileron servo 23 35 805
Right wing aileron servo 23 35 805
Left Tailing aileron servo 20 48 960
Right Tailing aileron servo 20 48 960
Receiver + Electricals 60 9 540
Nose 31 21 651
Vertical Stabilizer 15 54 810
Rudder 15 57 855
Left wing aileron 10 32 320
Right wing aileron 10 32 320
Fuselage 342 26 8892
Wing 288 14 4032
Main Landing gear(Right) 30 16.5 495
Main Landing gear(Left) 30 16.5 495
Battery pack 480 10 4800
Left motor with mount 122 + 40 29 4698
Right motor with mount 122 + 40 29 4698
Tail motor with mount 50 + 40 78 7020
Monocot 5 0 0
Total 2011 47,260
Lateral Axis C.G = Total Moments / Total weight
= 47260 / 2011 = 23.5cm from the Datum point
131
The Centre of Gravity of Aero-‐chopper falls on
34cm from the tip of the nose, 36.7 cm from the tip of the right motor
mount and 23.5 cm from the tip of the landing gear.
132
PERFORMANCE ANALYSIS
Formulae used throughout the report
Lift and drag calculation
• Lift (L) = ½ ρV2SCL
• D = Cads
• CD = CDP + CDi
• CDP = (Cf * k * Swet)/Sref
• MAC = 2/3 * CR(1 + σ -‐ σ/1+σ)
• RN = ( Vo * L)/vv
• CF = 0.455/(Log RN)2.54
• CF = 1.328/√RN
• CDi = CLcruise2/πARe
• e = 1/[πARK + 1/(u * s)]
Climb performance
• (R/C) = TV∞ -‐ DV∞ / W
Take-off Performance
• Sa = RsinθOB
• Sg = 1 / 2gKA ln(1 + KA/KT x V2LO ) + NVLO
• R = 6.9(Vstall)2 / g
• θOB = cos-‐1 (1-‐ hOB / R)
• SƟ = 1/2gK
• KT = (T/W) -‐ µT
• G = (16h/b)2 / 1 + (16h/b)2
133
• VLO = 1.1 * Vstall
• CD,O ~ ∆ CD,O = w/s * Kucm-‐0.215
• KA = ρ∞/2(w/s) [CD,O + ∆ CD,O + ( K1 + G/ πeAR) CL2 = µrCL ]
Landing Performance
• Vf = 1.15Vstall
• R = Vf2 / 0.2g
• hf = R(1 -‐ cosθo )
• So = S-‐ hf / tanθa
• Sa = 50 -‐ hf / tanθa
• Sf = R sin θa
• JT = Trev / W + µr
• JA = ρ∞ / 2(w/s) [CD,O + ∆ CD,O + ( K1 + G/ πeAR) CL2 = µrCL ]
• VTD = 1.15Vstall
Aircraft Maneuvers
• r = V2 / g * tan ϕ = V2 / g√(n2 -‐ 1)
• ω = V / r = V / V2 / g√(n2 - 1)
• ω = g√(n2 -‐ 1)
• r = V2 / g (n-‐1)
• ω = g (n-‐1) / V
• r = V2 / (n+1) g
• ω = g (n + 1) / V
• r = V2 / g * n
• ω = g * n / V
134
Helicopter performance
• ∆P = 1* ρ * V∞* V∞ / 2
• ∆P = Thrust / Area
• Vi = √(T/2*ρ*A)
• Pi = T * Vi
• Vh2 = (VC + Vi) Vi
• T = 2 * ρ * A * (VC + Vi) Vi
• Pi = T(VC + Vi)
• T = -‐2 ρA(VC + Vi) Vi
135
Troubleshooting After testing the plane problem with the following things occurred:
Landing Gear
Figure 90
The aircraft had crashed while taxiing. It was out of control when it had maximum throttle and
ended up having a bad crash resulting in a broken support section of the landing gear.
This was anyway fixed with epoxy glue 5min as the support material is plywood , making it
stronger and rigid.
136
Propeller Directional Balance
Figure 91
Before the VTOL aircraft was flown by itself , testing its balance of hovering was very important
or it could lead to a disastrous crash.
The balance was tested by holding the aircraft while full throttle was applied. Hovering was
achieved, but the balance of the both sides of the wing was not satisfying enough to let it fly on
its own.
The reason being, both the propellers on the either side of the wing were clockwise directional.
There was no counter support for the balance. The Counter-‐clockwise propeller could not be
found anywhere in the local country or nearby. So both clock-‐wise directional propellers were
tried anyway, resulting in a very unstable balance.
137
Throttle Balance
Figure 92
The self-‐hovering of the aircraft model was put to test after the previous troubleshooting was
taken care. The problem of Throttle balance did not allow the flying to be achieved.
The tail-‐motor that was fixed to upwards direction was restricting the airplane to take-‐off as the
power of the Tail-‐motor was greater than the ones on the wing. The wing-‐motors also faced a
difference in power produced, which got the aircraft pushing itself sideways and not taking off
vertically.
This problem was corrected by fixing one main gyro board to all the controls intending to trim
the power produced and help the controls to perform uniformly. But unfortunately the electrical
components did not respond to the gyro board even after proper fixing was done.
138
Safety and Risk Assessment
• When working with glue, accelerator or acetone, remember that they are toxic and
hazardous materials. Follow all guidelines and precautions accompanying these
materials. It is easy to become complacent, as the hazard is not immediately obvious.
• Always wash hands after working with glue materials. Keep glue, accelerator and
acetone away from the eyes. Safety glasses are recommended. Avoid rubbing the eyes,
and keep the hands away from the face when working with these materials
• If power tools are used, eye protection, instruction in the safe use of the tools and
proper supervision should all be considered prerequisites.
• If not flying at a club field, make sure the site you choose is adequate and appropriate
,not too small an area and not too close to people, animals, trees, power lines, buildings,
roads, etc. Also find out if there are any local ordinances that prohibit flying RC airplanes
in public spaces.
• When working with a hand cutter make sure not to apply big forces as it might lead to
hurting your hand.
• Unless your radio system is 2.4GHz, use a frequency checker or some other method of
frequency control before turning on your transmitter. Having two or more people flying
RC airplanes on the same frequency does not work; if you interfere with another pilot’s
frequency, you will cause an accident.
• Never ever keep your hands close to the engine propeller blade it can cut anything with
the speed of 17,000 rpm.
• Don’t try flying RC airplanes in “adverse” wind conditions. Depending on your model,
that could be anything over 10-‐15 mph. Know your plane’s limitations and if unsure
about wind speed, wait for another day.
139
CONCLUSION
Based on the theoretical calculations Aero-‐chopper was successfully designed and constructed.
Aero-‐chopper has been designed to accomplish VTOL and transition to forward flight.
By completing this project it has enlightened me on many topics such as the Helicopter and
Aircraft performance individually and together.
Since Aero-‐chopper is almost a successful project, and it explains the concept of vertical take-‐off
and landing, in future we hope to see the real aircraft perform vertical take-‐off and transition
and bring alive the legendary V-‐22 osprey.
I would like to conclude by saying that according to the study conducted, calculated results and
the test performed Aero-‐chopper can perform VTOL and transition to forward flight with no
hustle.
140
References
1. http://www.theuav.com/
2. espritmodel.com
3. helicopterpage.com
4. http://www.moneysmith.net/Soaring/soaring4.html
5. www.e-‐fliterc.com/Products
6. http://www.worldofkrauss.com/foils
7. Fundamentals of Flight by Richard S Shevell
8. Basic Helicopter Aerodynamics by J.Seddon
141
Index
3
3D Drawing ·∙ 54
A
ABSTRACT ·∙ 8
Acknowledgement ·∙ 4
AIRCRAFT DESIGN ·∙ 47
Airfoil Selection ·∙ 42
Area Calculation ·∙ 78
C
CENTRE OF GRAVITY ·∙ 128
CONCLUSION ·∙ 139
CONSTRUCTION (ASSEMBLY) ·∙ 58
COST ANALYSIS ·∙ 21
D
DESIGN CONCEPT ·∙ 19
E
ELECTRICALS ·∙ 32
G
GANTT CHART ·∙ 17
GRAPHS ·∙ 74
I
INTRODUCTION ·∙ 5
M
MAN POWER ·∙ 23
Materials ·∙ 27
Mission ·∙ 16
P
Parametric Study ·∙ 10
PERFORMANCE ANALYSIS ·∙ 97, 132
R
References ·∙ 140
S
Safety and Risk Assessment ·∙ 138
SCOPE ·∙ 8
Specifications and details ·∙ 10, 12
Structure designing :(PROFILI) ·∙ 49
T
Tools ·∙ 30
Troubleshooting ·∙ 135
142