Stevens2007 - Stevens Institute of Technology · · 2007-03-24The needs vs. metrics matrix ......
Transcript of Stevens2007 - Stevens Institute of Technology · · 2007-03-24The needs vs. metrics matrix ......
Stevens Institute of Technology
2007 SEA Aero Design East Report i
Stevens2007
Team Number: 053
Stevens Institute of Technology
Team Members: James Koryan, Joseph Lojek, Justin Sommer, Ramy Ghaly
Stevens Institute of Technology Stevens2007 – Team # 053
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Abstract
This report presents a design for an aircraft capable of lifting the maximum load; maximizing the
payload ratio. The design was developed according to the specifications of the 2007 Aero Design
competition rules. An optimal design was developed by maximizing the aerodynamic lift and reducing
the aircraft weight without compromising performance. An RC controlled plane is currently being
constructed for participation in the competition.
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Table of Contents
Compliance ii Abstract iii Introduction 1 Design Approach 2 Design 4 Thought Process 4 Wing Design 4 Wing Shape 5 Airfoil Selection 5 Control Surfaces 6 Wing Strategy 7 Fuselage 7 Landing Gear 8 Engine Cowl 8 Tail-plane 8 Construction 9 Wing 9 Fuselage 10 Construction Strategy 10 Tail Construction 11 Landing Gear Construction 11 Electronics used & Wiring Needed 11 Final Construction Touches 12 Calculations 12 Stability 17 Payload Prediction 19 Conclusion 19 Lessons Learned 19 Additional Sources 20 Software Utilized 20 References 20 Literature 20 World Wide Web 20 Appendix A - Payload Prediction Plot 21 Appendix B –Electronic Plan 22 Appendix C – EES Payload Prediction Calculations 23
Stevens Institute of Technology Stevens2007 – Team # 053
2007 SEA Aero Design East Report 1
INTRODUCTION
Research and design began shortly after the start of the 2006-2007 school year, immediately after the
team was assembled. The team consists of four members each focusing in mechanical engineering at
Stevens Institute of Technology. The project has been the teams focus for the senior design project and
all requirements were to be completed by the team. Many hindering factors were faced but were
overcome with dedication and perseverance. The team noted that scheduling would be one of the
hardest obstacles since each member had drastically varying schedules. Tools such as Gantt charts
were applied to the process to help with time management and guidance to a successful project. Project
management and organizational skills were essential to the success of the project.
With time and responsibilities allotted to each member further work commenced. Brainstorming,
research and calculations soon became the next step of focus. Various sources were used in educating
the team in fluid mechanics, aerospace design, and the construction of an airplane. Research involved
reading and studying an assortment of texts and publications in the design of RC model planes and flight
theory. Drafting ideas and modeling airfoil types quickly followed the team’s research.
Using a multitude of software and mathematical models, optimization of the final design began. Once
the optimum design was obtained construction of the fuselage, wing, and other components followed.
Using simple craftsmen techniques, tedious labor, and extreme attention to detail, the design team
slowly assembled the airplane. The final components were then mono-coated and the plane was
prepared for test flights.
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DESIGN APPROACH
To focus the team’s initial ideas into a weighted concern, a list of needs and metrics was created. The
list of needs consisted of all the necessary concerns involved in designing a compliant aircraft to this
year’s competition and successful design. The list of needs can be seen below in Table 1.
Table A - Needs Table
Following the construction of the needs, the team instituted a metrics of critical properties of the aircraft to be weighted as noted Below in Table B.
Table B - Needs-Metrics Table
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The next step was to weigh the needs versus metrics and then observe the focal points of the teams
design. Each need and metric was assigned a value according to its importance. The needs and metrics
that had the most importance received the higher values. The needs vs. metrics matrix (Table C)
provided the team with a clear view of the most important factors of the design.
Table C – Need vs. Metrics Matrix
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DESIGN
Thought Process
Soon after receiving this assignment the team sought out reference materials in radio controlled model
airplane design and construction as well as advice from several professors. In previous Aero Design
competitions attended by Stevens Institute of Technology several entries have been overly designed and
didn’t perform as expected. The team gathered that the problem behind this event was concerning the
fabrication of a plane that accurately resembles the original concept. The accuracy to which we construct
our plane will govern the predictability of its performance. The main goal of the team was to design a
plane that carries the maximum weight possible. While taking under consideration the problems that
may arise during the construction phase, the team decided to implement the simplest most effective
designs and concepts.
Wing Design
There are several types of airplane configurations that fit with in the specifications of the competition
that the team had to choose from. The team spent time brainstorming and presented ideas to each other
which consisted of wing configurations, airfoil profiles and other body configurations. The team’s first
decision was between the monoplane, bi-plane, tri-plane, and delta wing designs. The team chose the
monoplane design because it was the most common design and the design that the team presumed to be
easiest to construct.
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Wing Shape
The team also decided to implement a straight wing shape as opposed to the elliptical, tapered, or swept
wing shapes. Although the elliptical, tapered, and swept wing shapes provide better spanwise lift
distribution and a reduction in wing tip losses the team opted for the straight wing design because of its
ease of construction. However to compensate for the differences between the straight wing shape and the
other shapes the team researched several methods of reducing wing tip losses and optimizing spanwise
lift distribution. Winglets, endplates and Hoerner tips were among the methods discussed by the team.
As stated before the team chose the simplest and most effective design which was the endplates. The
winglet and the Hoerner tip provide similar effects as the endplate but the group decided that the
complicated design would not be feasible to construct in the allotted time. From here the team
researched airfoils that were designed to have high lift coefficients.
Airfoil Selection
The team used programs such as Xfoil and WinFoil as well as internet resources to analyze and acquire
the best airfoil for our design. The team also analyzed the airfoils used in previous competitions. We
gathered that an airfoil with a slender trailing edge would pose difficulty in reproducing with the current
equipment available to us. The Eppler 423, the Selig 1210, the Aquila and the Clark Y (Figure 1) were
among our top choices. The Eppler 423 and the Selig 1210 have very high coefficients of lift, unlike the
Aquila and Clark Y profiles. However the Aquila and the Clark Y have simpler geometries because of
the thicker trailing edge and lower camber, making them the easiest to build accurately. The team chose
the Eppler 423 because it has the highest lift coefficient and a thicker trailing edge than the Selig 1210
(Figure 2).
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Figure 1 - Lift Coefficient vs. Angle of Attack
Figure 2 – Eppler 423, Selig 1210
Control Surfaces
The team believed that the proper construction of the control surfaces will have the greatest effect in the
performance of the plane. The flaps, ailerons, elevator and the rudder control surfaces have been
designed to be simple and effective. The team used proportions similar to the suggested proportions for
flaps and ailerons from the Basics of R/C Model Aircraft Design by Andy Lennon. The team referenced
this book in several other applications to be mentioned later in the text. Calculations were also done to
Cl Vs. AOA
-0.5
0
0.5
1
1.5
2
2.5
-6 -4 -2 0 2 4 6 8 10 12 14 16
AOA
Cl
E423 Re: 200000 AQUILA, Re:101100 AQUILA, Re:150500 AQUILA, Re:203900 AQUILA, Re:301100 Clark Y, Re:63100
Clark Y, Re:20380 E-423, RE: 60300 E-423, RE: 198600 E-423, RE: 296900
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ensure that the control surfaces were effective and that the plane would fly. The calculations will be
further explained later in the text as well. There were several types of flaps that were discussed as well
as leading edge heavy lift devices. Implementing a complicated flap design would prove beneficial with
respect to the increased lift and other flight performance characteristics. Nonetheless the team decided to
implement a plain-flap design because of its simplicity. The leading edge heavy lift devices were taken
out of consideration due to our lack of knowledge and the technical skills to construct them properly.
Wing strategy
The full wing span is 80 inches and the rectangular fuselage has a width of 6 inches. Since the design of
the shape of the body has been chosen to be a high-wing monoplane, the team members have considered
the following methods in constructing the wings relative to the fuselage The first method was to
construct the whole wing then have it glued to the top of the fuselage. The next method was to cut out a
groove in the fuselage for mounting the wing. The groove is shaped according to the airfoil dimensions
in efforts to reduce wing body losses. The last method consisted of a three part wing which comprised of
a left, right, and middle section. The middle section is permanently attached to the fuselage and the other
two wing sections will slide into position and locked in place using pins and slots. This enables the team
to detach the wings for easy transportation and more importantly the capability of replacing damaged
wing sections. Also, the middle section will be properly reinforced to handle the wing loading.
Fuselage
The fuselage has a rectangular cross section which tapers off after the payload area. Originally the team
considered a circular or elliptical cross-section that tapers off towards the tail because it has less drag
than a rectangular cross-section fuselage. The team ran into complications determining how to attach the
landing gears and the middle wing section to the fuselage with out creating too much drag and
compromising hull integrity. The landing gear needed to be mounted to a flat surface. The team
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contemplated mounting the landing gears to a rectangular frame located inside the fuselage and then
cutting holes in the exterior shell to allow the landing gear to protrude out. The holes obviously will
increase the drag and the deformation of the landing gears during landing may break the exterior shell.
The rectangular cross-section fuselage provided a flat surface required to mount the landing gear without
an added difficulty. The wing construction and assembly will be discussed later in the text. The engine
will be mounted to a section of ply-wood and an
Landing Gear
The tri-cycle landing gear layout was chosen over the tail-dragger layout because it has superior steering
during take off and landing and it’s the most commonly used layout. The team considered different
types
Engine Cowl
The engine cowl will cover the engine to reduce drag created by the frontal area of the fuselage. The
team speculated that the best engine cowl would one provide a smooth transition from the nose to the
fuselage. A conic shaped engine cowl would have been ideal if then team had continued with a
cylindrical shaped fuselage. The team decided to buy the cowl because. In addition, the price of the
engine cowl is relatively cheaper than the price the student would have had to pay for time and effort put
in constructing it.
Tail-plane
The team will be using a “T-Tail” design for the final designed aircraft. It was debated whether or not to
use other designed tails such as a “V-Tail” or a tail with its horizontal wing below the vertical rudder.
All types were analyzed and studied for their theoretical traits. It was the “T-Tail” design that proved to
be most beneficial for our application.
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CONSTRUCTION
After the team chose which of the conceptual designs to apply to the final design, the members started
the construction process. First, the group members thought of different methods to construct the
airplane’s components as well as how to assemble all of them together. Below is a discussion of the
different methods thought of by the group members and the optimal method that was chosen.
Wing
The team began with making stencils of the Eppler 423 airfoil profile. The stencils were cut from 1/8"
balsa wood sheets and formed the ribs. The left and right wing sections have twelve ribs that span a
total length of 33”. The ribs were mounted on carbon fiber tubing; as described in the design section in
this report. The flaps and ailerons with a cord length of 2.75 inches will span the majority of the wing.
A 1/2" hole was then made at the theoretical mean aerodynamic point of the airfoil where a 3/8" carbon
fiber tube was then inserted and glued. It is at the mean aerodynamic point where all forces are assumed
to be acting. A second hole was then drilled in the ribs. The ribs were fixed in their proper places. Two
carbon fiber tubes were put through the holes. Before gluing the ribs to the tube, the ribs were first fixed
in a clamping system designed by the group members to ensure there stability for a day until the glue
hardens.
As of this date, March 21, 2007, the team has only finished the above constructions. However, in the
following weeks the team is aiming to finish constructing the wings. The two flap portions on each side
of the wings will be connected together through the fuselage with a carbon fiber tube that runs through
the holes made in the ribs of the flaps. Holes were also made in the ailerons’ ribs where each aileron on
each side was made by connecting the ribs by carbon fiber tubes. The reason two separate tubes were
used is because each aileron will be connected to a different servo since they will be deflected in
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different direction with different angles. Thin balsa sheets well by used to cover the skeletons of the
fixed portion of the wing, the flaps, and the ailerons.
Fuselage
This section contains the teams’ considered construction methods and will list and justify the reasons
why the chosen method is optimal. The team considered constructing rectangular ribs and connecting
them with four carbon fiber tubes that run through each corner of the ribs and building a frame and
cover it with thin sheets of balsa.
The previous considerations were listed in order to compare to the chosen method for justification
purposes. The team is assuming that the airplane will drop a distance of 3 feet while landing. The impact
that is exerted on the landing gear will be delivered to the bottom side of the fuselage. It is known from
previous designs that balsa wood will not be the best suited material to use to absorb this impact force
that is exerted upon landing. As a result the team members have decided to use a stronger material to
absorb the impact. The team decided on a plywood due to its relative light weight and strength. It is also
one of the easiest materials to work with; easy to cut and glue.
Construction strategy:
As of this date, the team did not yet start construction of the fuselage. However, the strategy that the
team is to follow is a: 6”x48” rectangles will be cut on 1/4" balsa sheets. The three sides will be glued at
their corners with the use of an L shape light balsa sticks. The bottom side of the fuselage will be made
out of plywood. As described above, 4 inches of each wing on either side will be fixed to the fuselage.
They will be glued and reinforced by using carbon fiber tubes that run through the fuselage and the wing
set on both sides of the fuselage.
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Tail construction:
The method of construction to be used for the horizontal tail is similar to that of the main wing. The
chosen design and the strategy to be followed are similar to the main wing. The ribs will be a profile of
NACA 0009 airfoils and constructed from balsawood. Fiber rods will once again be used to support the
construction of the tail and finally thin, light balsa sheets will be used to cover the skeleton. The same
will be done to the rest of the horizontal tail; however, it will be fixed relative to the body of the
airplane.
The vertical tail will be made out of a vertical NACA0009. At its top, the horizontal tail will be fixed. Its
bottom will be fixed to the top of the fuselage by strong glue and reinforced with L shape pieces of
stronger balsa.
Landing gear construction:
The school, Stevens Institute of Technology, currently has two sets of commercial landing gears and 4"
wheels that were used in previous years and have showed an accepted performance. As a result, the team
has decided to use them to save time, effort, and cost. In addition, the available landing gears are made
with fine finish to decrease the surface drag induced.
Electronics used and wiring needed:
The team will be using five servos to control the airplane’s motion on ground as well as in midair
through the usage of a remote control. One servo will be controlling the two flaps. Two separate servos
will be used to control the ailerons since the two ailerons will be deflected in different directions as well
as with different magnitudes. Another servo will be connected to both the rudder and the front wheel.
The last servo will be connected to the horizontal tail. All the wires will that connects the servos to the
airplanes components, are hidden inside the fuselage and hidden for scenic purposes.
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Final construction touches:
Finally, the team will mono-coated all members to obtain the finest surface finish to minimize surface
drag. In addition, mono-coating will increase the rigidity of the relative parts of the airplane since it will
hold the relative parts together.
Calculations
The group utilized as many resources as possible for the plane's theoretical calculations, including, but not limited
to, "Basics of R/C Model Aircraft Design" by Andy Lennon, the "white paper" written by Dr. Leland M. Nicolai,
"Fluid Mechanics" by Frank White, and the SAE website. Previous groups from SIT predominantly used the
"white paper" as a general guideline; under the advice of our advisor, Professor Thangam, the team used the
guidelines presented in Lennon's R/C Model book and mathematical models from the “Fluid Mechanics” textbook
in addition to Nicolai’s “white paper”. While the "white paper" produces a sufficient model, the team agreed that
it would be more accurate and practical to use empirical data for smaller model planes (provided in Lennon's
book) where possible rather than to try and use formulas associated with larger aircraft. Aircraft calculations do
not scale down accurately, and the group has adjusted our model to reflect this, replacing some calculations with
experimental data.
The group utilized EES to assemble the mathematical models; these models have been adjusted and refined many
times in order to produce the most accurate performance prediction possible. The models have now been
arranged so that the input entries are the runway distance, the weight, air density constants, and dimensions of the
aircraft; from this, EES determines takeoff velocity, the thrust required to takeoff at that velocity, the engine
thrust at that velocity, and also the runway distance required for landing.
The group uses two basic models to calculate performance. The first comes from “Fluid Mechanics”. The group
used a force balance in the direction of takeoff which is
Stevens Institute of Technology Stevens2007 – Team # 053
2007 SEA Aero Design East Report 13
RkVTRollingDragThrustdtdvmFs −−=−−== 2 [EQ-2]
where R is the rolling resistance, and k is defined as follows:
∑= effectiveD ACk ρ21
. [EQ-3]
The second model comes from Nicolai’s “white paper”, and it uses the mean acceleration for takeoff instead of
dV/dt. This turns our force balance into
)( rolldmean FFTma −−= , [EQ-4]
where mean
TO
aV
s2
2
= , [EQ-5]
and s is the distance allowed for takeoff.
Each aspect of the plane (the wings, fuselage, landing gear, flaps, etc.) adds to the total drag force and must be
accounted for in order to depict our plane accurately. The CD values for each respective aspect were calculated
using the model in Nicolai’s “white paper” and the results are tabulated in Table E.
CD values
Table E – Drag Coefficients
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2007 SEA Aero Design East Report 14
In order for this model to produce an accurate prediction, the drag coefficients and the effective areas must be as
close as possible to the actual areas during taking off. During takeoff and landing, the effective lifting area is
reduced because the flaps are down (which must be incorporated into the stall velocity calculation), and more
blockage drag must also be taken into account (distance calculation). The ΣCDAeffective calculation was performed
with
)()()()()( LGdLGvwingdvwinghwingdhwingplanformdwingfusedfuseeffectived ACACACACACAC ++++=∑
)()()( flapsdownkagedflapsblocafrontalArekagedfrontblocenginedengine ACACAC +++ [EQ-6]
for performance prediction during takeoff and landing. The angle of deflection for the flaps during takeoff was
taken to be 13 degrees and during landing to be 20 degrees. This has been accounted for in terms of wing
planform area reduction and also in terms of frontal blockage (creating more drag). It also is incorporated in the
calculation of the lift coefficient. The lift coefficient is a function of the max camber of the airfoil (in our case,
the Eppler 423), the angle of attack of the wing, and the angle of deflection of the flaps. CL is calculated as
follows:
)2sin(/)2sin(*max/ ch
chCC flapLflapsLw +++= ααα [EQ-7]
The coefficients of lift and the ΣCDAeffective values for the different parts of our flight are in the following table.
Lift Coefficients
Table F – Lift Coefficients
The group decided to simplify the model for takeoff by ignoring the Rolling resistance because it is very small
and has little effect on the overall takeoff calculation. This reduces the model to
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2kVTDragThrustdtdvmFs −=−== [EQ-8]
and )( dmean FTma −= [EQ-9]
where kV2 is the drag force at takeoff. The takeoff velocity is easily obtained by first obtaining the stall speed
(Vs). The stall speed is found with
21
)2(PLMax
S ACWVρ
= , [EQ-10]
where CLMax is the lift coefficient with the flaps and ailerons in takeoff position, ρ is air density at sea level, and
AP is the planform area of the wing. In order to insure takeoff, the takeoff velocity must be at least
STO VV 2.1= [EQ-11]
On another note, the SAE rules dictate a takeoff runway of only 200 feet, which means that distance is important
to determine because it’s a constraint; however, the time required to takeoff is not. Therefore, we substitute the
following into our model,
dsdVV
dtdV
= . [EQ-12]
After separating variables and integrating, we discover that
∫∫ −=
TOVS
kVTVdVmds
02
0 )(2, [EQ-13]
and 2ln2 TO
o kVTT
kmS
−= ; [EQ-14]
we can set the takeoff distance to be 190 feet (leaving 10 feet for error), and solve for the thrust required to
takeoff with mass m.
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2007 SEA Aero Design East Report 16
The next problem to address was to determine what thrust our engine could provide. By definition, power is
VelocityThrustPower *= ; [EQ-15]
the power output of the engine is known, and so is the velocity (VTO), and so the thrust available from the engine
can be determined. The group then compared the required thrust for certain weights and matched it to find the
maximum load our plane can lift off the ground. The results are tabulated in the following table.
Thrust
Table G - Trust
When the plane weighs a total of 25 lbs, both mathematical models produce a required thrust that is less than the
available thrust. Anything more and we surpass the payload limit. Therefore, we will assume a maximum weight
of 25 lbs for takeoff.
Next, the cruising velocity must be calculated. At level flight, the weight will be the same as the force of lift.
This translates to
pL ACVLiftlbsWeight 2
2125 ρ=== , [EQ-16]
and, after solving for velocity using a lift coefficient of 2.018, an air density for an altitude of 1000 ft above sea
level, and an unflapped wing planform area. This yields a cruise velocity of 41.91 ft/s (28.6 mph). This is a very
reasonable velocity for model aircraft.
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All that is left to be calculated is the landing distance. For this calculation, the group referred to Anderson’s
“Introduction to Aerospace”. For the landing distance,
VTR
T
L LWDragg
WVS
7.0
2
)]([2
)(
−+=
μ [EQ-17]
The sum of the forces in the denominator should be the instantaneous value, but for simplification, we take the
average value (which is at 0.7VT). VT is the velocity that the plane comes in at to land. To assume a factor of
safety, we take this to be
StallT VV 7.1= [EQ-18]
While there is also still a thrust from the propeller (we cannot simply shut off the engine), we can assume that it
will simply increase our landing distance by a small factor. From our model, the group attained a landing distance
of 57.3 ft (well within the allowed limit of 400 ft). Increasing this distance by 50% (due to the ignored engine
thrust) puts the distance to 86 ft, which is acceptable.
Stability
The pitching moment plays an essential role in a stable and level. The pitching moment was determined
using the equation (EQ-19) found in Basics of R/C Model Aircraft Design by Andy Lennon. The team
analyzed the effects of speed and chord length on the pitching moment (Table H). The wing was found
to have a nose down moment and due to its high camber the moment was rather large.
Pitching Moment = (CM * s * V2 * S * C) / 3519 [EQ-19]
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2007 SEA Aero Design East Report 18
Table H – Sample pitching moment
Where CM is the pitching moment, s is the density of air at sea level s=1, S is the wing area in in2, and V
is the velocity in mph. The pitching moment was then used to determine the horizontal tail area (HTA)
needed. EQ-20 was from the Lennon book as well. The wing area (WA), the mean aerodynamic chord
(MAC) and the HTA were used to determine the length of the tail moment arm in EQ-3.
HTA = (2.5 * MAC * 0.20 * WA) / TMA [EQ-20]
TMA = (2.5 * MAC * 0.20 * WA) / HTA [EQ-21]
Tail Moment Arm in. Wing area: 880 in2 Wing area: 800 in2
Wing Chord Length in. HTA at 180 in2 HTA At 200 in2 10 36.67 20 11 40.33 22 12 44 24
Table I – Sample Tail Moment Arm Length
The team was able to determine that the plane will have a level flight.
Pitching moment lbs/in Wing area: 880 in2
Take – Off Cruise Chord Length
(C) in. at 20 mph at 50 mph
10 -21.61 -135.09 11 -23.78 -148.6 12 -25.6 -162.1
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Payload Prediction
The Payload prediction graph (see Appendix A) was generated using an EES code (see Appendix D).
This information states the maximum allowable weight that could be lifted at increased altitudes. The
graph portrays a linear plot with a Predicted Payload = {31.02-0.001 x Density Altitude}.
Conclusion
In conclusion, the team was able to apply the skills and knowledge attained at Stevens Institute of
Technology. Through strong team leadership and dedication the team was successful in their efforts.
Project management played a key role in the completion of the design and construction. It allowed the
team to meet all deadlines and organize responsibility within the group. Also, with the aid of the team’s
advisor and other noted references the construction of the aircraft was made feasible. Based on the
construction of the plane and theoretical calculations the team feels that the plane will do very well in
this year’s competition.
Lessons Learned
The unique experience of this project enabled the team to obtain many new skills. There was a great
deal of knowledge and lessons learned involving the brainstorming process. After a semester of
working as a team we discovered that brainstorming is needed to lead a strong and competitive design.
Discussion techniques were often used when developing concepts for design and as a group we were
capable in focusing our thoughts into one collective idea. Team unity strengthened greatly over the
course of the term. We were able to obtain a wider understanding of each others working habits and
weaknesses. Knowing where the group lacked strength enabled the team to increase the concern in
those areas.
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2007 SEA Aero Design East Report 20
Additional Sources
Software Utilized
Engineering Equation Solver (EES), Microsoft Office, Solid works, Winfoil, Matlab, Xfoil
References
Literature
F. M. White, Fluid Mechanics, 5th edition, McGraw-Hill, New York, NY, 2003
Andy Lennon, Basics of R/C Model Aircraft Design
Nicolai, Dr. Leland M, “The White Paper”
Tower Hobbies, Tower Talk, Issue #6, December 31 2006
World Wide Web
www.sae.org
Stevens Institute of Technology Stevens 2007 Team 053A di Ay = ‐0.001x + 31.01
R² = 0.999
35.00
Stevens Institute of Technology ‐ Stevens 2007 ‐ Team 053Payload Weight vs Density Altitude
Appendix A
30.00
20.00
25.00
t [lb]
15.00
Payloa
d Weight
10.00
0.00
5.00
0.00
0 1000 2000 3000 4000 5000 6000
Density Altitude [ft] 21
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B
AA
B
C
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8 7 6 5 4 3 2 1
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REV
UNLESS OTHERWISE SPECIFIED:
SCALE: 1:15 WEIGHT:
Team: 053PROHIBITED.
PROPRIETARY AND CONFIDENTIAL
NEXT ASSY USED ON
APPLICATION<INSERT COMPANY NAME HERE> IS WITHOUT THE WRITTEN PERMISSION OF
DWG. NO.
REPRODUCTION IN PART OR AS A WHOLE B<INSERT COMPANY NAME HERE>. ANY
SIZEDRAWING IS THE SOLE PROPERTY OF
TITLE:
THE INFORMATION CONTAINED IN THIS
Stevens Institute of Technology
THREE PLACE DECIMAL
TOLERANCING PER:
MATERIAL
FINISH
DRAWN
CHECKED
ENG APPR.
MFG APPR.
Q.A.
COMMENTS:
DATENAME
DIMENSIONS ARE IN INCHESTOLERANCES:FRACTIONALANGULAR: MACH BEND TWO PLACE DECIMAL
INTERPRET GEOMETRIC
DO NOT SCALE DRAWING
Class Regular
Data SummaryWing Span 80"
Empty Weight 10 lbEngine
Make/Model O.S. 61FX
Appendix B - Electronic Plan
11.00
2.75
4.50
80.0
0
15.0
0
6.00
12.00
3.24
24.00
6.00
6.25
7.69
6.25
64.63
12.12
Stevens Institute of Technology Stevens2007 – Team # 053
2007 SEA Aero Design East Report 23
Appendix C
Payload Prediction Constants" E=700 "Elevation of Fort Worth, TX" R=1715.7 "Universal Gas Constant" B=.003566 "Adiabatic Lapse Rate" g=32.2 "Force of Gravity" T_0=518.69 "Temperature at Sea Level, Rankine" p_a=2116.2 "Atmospheric Pressure at Sea Level" mew=3.7373*10^(-7) "Air Viscosity" c=11 "Chord Length, Inches" MSL=1000 "Mean Sea Level, Feet" A_p=880/144 "Planform Area, Feet^2" V=52.93 "Cruise Velocity" C_L=2.018 "Lift Coefficient at Cruise" W=10 "Empty Weight of the Aircraft" "Calculations" AGL=MSL+E "Above Ground Level" T=T_0-B*MSL "Adjusted Temperature" p=p_a*(1-(B*MSL/T_0))^K "Adjusted Pressure" K=g/(R*B) "Equation Simplification" rho=p/(R*T) "Air Density" DA=145366*(1-(17.326*P/T)^.235) "Density Altitude" Re=(rho*V*c/12)/mew "Reynolds Number" q=.5*rho*(V^2) "Calculated Value" Lift=(C_L*rho*A_p*V^2)/2 "Lift Force" Payload=Lift-W "Payload Calculation"