January 14th of 2013
The Study of Sound in a Flight Induced Airflow
Madison West High School - Returning Team
SLI 2013 Critical Design Review
Madison West High School
Returning Team
SLI 2013 CDR
Contents
Summary ........................................................................................................................ 4
Changes Made Since PDR ............................................................................................ 5
Changes to vehicle ...................................................................................................... 5
Changes to Payload ..................................................................................................... 5
Changes to Project Plan .............................................................................................. 5
Vehicle Criteria .............................................................................................................. 6
Mission Performance Predictions............................................................................... 11
Deployment and Recovery ......................................................................................... 15
Parachutes ............................................................................................................. 16
Drift ........................................................................................................................ 16
Universal Avionics Platform - System Hermes ....................................................... 17
Vehicle Verification .................................................................................................... 18
Performance Targets that Apply to Vehicle ................................................................ 20
Vehicle-Payload Integration ....................................................................................... 20
Vehicle Launch Procedures ....................................................................................... 21
Vehicle Safety ............................................................................................................ 21
Payload Criteria ........................................................................................................... 22
Selection, Design and Verification of Payload Experiment ........................................ 25
Measurements ....................................................................................................... 25
Data and Correlations ............................................................................................ 25
Hypotheses ............................................................................................................ 26
We make the following hypotheses: ....................................................................... 26
Post Flight Procedure............................................................................................. 26
Payload Concept Feature and Definitions .............................................................. 26
Payload Verification ................................................................................................... 27
Payload Safety ........................................................................................................... 27
Section 508 Compliance .............................................. Error! Bookmark not defined.
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Madison West High School
Returning Team
SLI 2013 CDR
Safety ........................................................................................................................... 28
Written Safety Plan .................................................................................................... 28
I. NAR Safety Requirements ...................................................................................... 28
II. Hazardous Materials .............................................................................................. 29
III. Compliance with Laws and Environmental Regulations ........................................ 29
IV. Education, Safety Briefings and Supervision ........................................................ 30
V. Procedures and Documentation ............................................................................ 30
Physical Risks ............................................................................................................ 31
Toxicity Risks ............................................................................................................. 31
Scheduling and Facilities Risks.................................................................................. 31
Rocket/Payload Risks ................................................................................................ 32
Educational Engagement ........................................................................................... 33
Outreach Programs.................................................................................................... 33
Project Plan ................................................................................................................. 35
Schedule .................................................................................................................... 35
Budget ....................................................................................................................... 37
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Madison West High School
Returning Team
SLI 2013 CDR
Summary
Team Name
Madison West High School – Project Mach 1
Location
Madison, WI
Title of Project
The Study of Sound in a Flight Induced Airflow
Mailing Address
Ms. Christine Hager
Madison West High School
30 Ash Street
Madison, WI
Team Mentor
Mr. Brent Lillesand, NAR/TRA Level-3 certified
Launch Vehicle Summary
Length:
Diameter:
Liftoff Weight:
Motor:
Recovery System:
Milestone Review Flysheet:
73”
2.6”, 4.0”
7.5lbs
AT J415W
18” drogue (at apogee), 60” main (700ft), dual
Perfecflite StratoLogger altimeters (fully redundant)
submitted separately
Payload Summary
We will be investigating the effects of near sonic airspeeds on the behavior of sound
waves. We will build a high velocity miniature wind tunnel in our rocket on the basis of
the Bernoulli principle and de Laval nozzle. Intake tubes on the face of the rocket will
scoop air into tubes inside the rocket. The air will be accelerated to near sonic speeds
when it is funneled into a smaller chamber (de Laval nozzle). At both ends of the nozzle
is a microphone with a recording device for registering sound. In the throat of the nozzle
is a sound generator (strong piezo beeper) that will emit short loud sound pulses at
regular intervals. The sound pulses will be emitted at regular intervals and the
microphones will record sound as it arrives. We expect to see volume change up to a
possible absence of the sound on the upstream end as the speed of fluid approaches
Mach 1.
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Madison West High School
Returning Team
SLI 2013 CDR
Changes Made Since PDR
Changes to vehicle






Designed transition between upper and lower part of the vehicle
Designed and flew scale model
Analyzed data from scale model flight
Based on scale model flight results, we selected a new motor
Using MagnaFrame tubing instead of fiberglass
Using G-10 fins instead of G-10 balsa sandwich
Changes to Payload

Designed transition between upper and lower part of vehicle
Changes to Project Plan
 No changes to Project Plan
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Madison West High School
Returning Team
SLI 2013 CDR
Vehicle Criteria
Technical Design
We will use a single stage, K-class vehicle for our experiment. We will be observing the
effects of supersonic air inside a moving rocket. The project code name of the vehicle is
Lodestar.
The rocket will be constructed from MagnaFrame tubing, using 1/16 inch G-10
fiberglass fins. The rocket will be robust enough to endure 25+g of acceleration and
high power rocket flight and deployment stresses.
The rocket will use dual deployment to minimize drift.
Mission Statement
To have a successful mission the rocket must reach (but not exceed) altitude of one
mile AGL and the payload must record all data necessary for our experiment. The
rocket will be 72 inches long, with a 2.6 inch diameter for parachute sections, and 4 inch
diameter for the payload and booster systems. It has estimated liftoff mass of 8.9
pounds. The proposed vehicle and propulsion options are discussed in detail below.
The primary propulsion choice is a K-class motor with total impulse of 2437Ns. The
vehicle can launch from a standard size, 8ft launch rail.
Construction and Test Flight Schedule
The construction and test flight schedule both for the subscale and full scale vehicles is
shown below. The testing with scale model will continue until all discovered design
issues are resolved at which point the full scale vehicle construction may begin. The full
scale vehicle is expected to make at least two test flight before the launch in Huntsville.
The last full scale vehicle test will use the same motor as the flight in Huntsville.
November 28
January 7
January 14/15
January 15
February 20
February 27/28
March 24/25
April 18/19
April 20/21
Begin work on scale model
Scale model completed
Scale model test flight
Begin work on full scale vehicle
Full scale vehicle completed
Full scale test flight #1
Full scale test flight #2 with payload
Flight hardware and safety checks
Launch day, full scale fight #3 at MSFC
Structural Subsystem
Entire Vehicle
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Madison West High School
Returning Team
SLI 2013 CDR
Figure 1: A two dimension schematic of the entire rocket. Stability margin for the
entire vehicle is 2.63 calibers
Vehicle Parameters
Length Mass Diameter
[in]
[lb]
[in]
Motor
Selection
Stability
Thrust to
Margin
weight
[calibers]
ratio
80
8.7
2.6/4
CTI-K660
2.63
17.37
Table 7: The rocket’s dimensions, stability, and primary propulsion
The figure below shows all compartments and section of our rocket. The rocket
separates into three tethered parts (nosecone, main parachute compartment (including
deployment e-bay), and the rest of the vehicle). We will use standard dual deployment
triggered by two fully redundant PerfectFlite Stratologger altimeters
Table 3: Rocket sections and parts
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Madison West High School
Returning Team
SLI 2013 CDR
Figure 3: Dimensioned drawing of the entire vehicle, showing the compartmentalization and load
bearing elements (bulkheads, tierods and U-bolts).
Propulsion Subsytem
Primary Motor Selection
Based on the results of computer simulations we have selected Cesaroni K660
(54mm) motor as our primary propulsion choice. Aerotech K1050W (54mm) and Animal
Motor Works K1075GG (54mm) are our backup choices. Characteristic parameters for
each motor are shown in the table below.
Motor
CTI K660
AT K1050W
AMW
1075GG
Diameter
[mm]
54
54
54
Total
Impulse
[Ns]
2437
2522
2392
Burn Time
[s]
3.57
2.37
2.15
-8-
Stability
Margin
[calibers]
2.63
2.57
2.59
Thrust to
weight ratio
17.4
27
23.9
Madison West High School
Returning Team
SLI 2013 CDR
Half Scale Vehicle Test
We have flown our half scale vehicle with the following parameters (shown in the table
below)
Liftoff weight
2.1 lb
Motor
Aerotech G75J
Length
41 in
Diameter
1.64 in. (body), 2.25 in. (body)
Stability Margin
1.6 calibers
We have sought the following test objectives:
• Test drogue and main parachute deployment
• Test flight electronics (altimeters and ejection charges)
• Test separation of body tubes at ejection
• Test validity of simulation results
• Test rocket stability
• Determine Coefficient of drag
As shown on the graph below, the half-scale model reached apogee of 1,382 ft
Underflying the simulation by 1195 ft. Model took 9s to reach the apogee.
We have used the scale model flight data to backfit the coefficient of drag (Cd) and we
have obtained value of Cd=1.06. Using this updated Cd we have recomputed our
mission performance predictions for the full scale vehicle and the most current estimate
of the full scale vehicle apogee is now
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Madison West High School
Returning Team
SLI 2013 CDR
Due to the nature of the payload, we expected an incredibly high Cd and subsequently a
much lower apogee than the Open Rocket simulation provided.
The transition required for the payload resulted in reduced vehicle performance, but did
not drastically impact the stability.
Issue
Mitigation
Extremely low apogee
Utilize a stronger motor
Weather cocking
Reduce gap between differing diameter
tubing
Very high Cd
Reduce drag where ever possible
Aerodynamic changes from payload
Utilize a stronger motor
affected performance (but not stability)
Table 6: Scale Model Flight – Lessons Learned: problems experienced during
scale model flight and proposed mitigations.
The graph below shows the simulated flight profile for the CTI-K660W motor. The
vehicle reaches the apogee of 5034ft thirteen seconds (13s) after the ignition. For the
purpose of this preliminary simulation the coefficient of drag is set to Cd= 1.06. This
result is obtained using Open Rocket software.
Figure 3: Altitude vs. time graph for CTI K660 motor. The entire rocket reaches
5034ft at 13s after ignition
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Madison West High School
Returning Team
SLI 2013 CDR
Mission Performance Predictions
Figure 3: Altitude vs. time graph for CTI-K660 motor.
The simulations indicate a small undershoot of the target altitude (5,280ft AGL) however
at this stage of the project we do not have enough information to decide whether this is
a real issue or just a simulation artifact. We will revise our simulations and make ballast
decisions after we carry out both scale model and full scale vehicle test flights. Our final
test flight before the SLI launch will use the same motor as we will use for our flight in
Hunstsville to make sure that the rocket will not exceed the target altitude.
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Madison West High School
Returning Team
SLI 2013 CDR
Wind Speed vs. Altitude
The effect of the wind speed on the apogee of the entire flight is investigated in the table
below. Even under the worst possible conditions (wind speeds of 20mph, the NAR limit)
the flight apogee will differ by less than 2% from the apogee reached in windless
conditions.
Wind Speed [mph]
Altitude [ft]
Percent Change in
Altitude
0
5034
0.0%
5
5013
0.4%
10
5003
0.6%
15
4984
1.0%
20
4966
1.4%
Table 10: Flight apogee vs. wind speed
Thrust Profile
The graph below shows the thrust profile for the K660W motor. The K660W motor
quickly reaches its maximum thrust of 1079N and declines steadily to 681N at 2.5s (the
average thrust-to-weight ratio is 17.37). The rocket requires a standard eight-foot rail
for sufficient stability on the pad and leaves the 8ft rail at about 80mph.
Figure 4: Thrust vs. time graph. The motor delivers maximum thrust of just over 1079 N and burns
for 3.57s
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Madison West High School
Returning Team
SLI 2013 CDR
Velocity Profile
According to the velocity profile, the rocket will reach maximum velocity of 701mph
shortly before the burnout (3.57s). The rocket remains subsonic for the entire duration
of its flight.
Figure 5: Velocity vs. time graph. The motor burns out at 3.57s and the rocket
reaches its maximum velocity of 701mph shortly before burnout. The rocket
remains at subsonic speed range for entire duration of its flight.
Acceleration Profile
The graph below shows that the rocket will experience maximum
acceleration of about 26g. Our rocket will be robust enough to endure the
26g+ acceleration shocks
Figure 6: Acceleration [g] vs. time [s] graph. The rocket experiences maximum acceleration of approximately 15g
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Madison West High School
Returning Team
SLI 2013 CDR
Mission Profile Chart
26g
4
3
2800
ft
3.72
0 ft s
2
1
5034
ft
13.4
s
5034
ft
13.4
s 5 700
ft
90 s
6
0s
0 ft
119
s
Figure 7: Vehicle flight sequence - 1. Ignition, 2. Burnout at 3.72s and 2805ft AGL, 3. Apogee at
13.4s and
5,034ft (drogue parachute deployment), 4. Descent under drogue parachute to 700ft, 6. Main
parachute deploys at 90s, 700ft, 7. Landing at 119s.
#
1
Event
Launch
Altitude
0
Time (s)
0
2
3
4
Burnout
Apogee
Drogue
Deployment
Main
Deployment
2800
5034
5034
3.72
13.4
13.4
700
90
Landing
0
119
5
6
Trigger
Launch
Control
Stratologger
Altimeter
Stratologger
Altimeter
Table 11: Flight events, triggers and conditions
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Apogee is
reached
Rocket
reaches
700ft AGL
Flight is
complete
Madison West High School
Returning Team
SLI 2013 CDR
Mass Statement




Our Rocket currently has a mass of 8.7 lbs, which includes a 4.3 lb K660
Cesaroni Motor.
This estimate of the mass comes from the Open Rocket Database where our
rocket is being designed.
The rocket would have to weight 30.6 lb, 350% of our current weight, before the
thrust to weight ratio drops below 5 (underpowered rocket)
Kinetic Energy at landing is: 5.37 ft-lbs for Nose Cone, 9 ft-lbs for Main
Parachute Tube, 23.5 for Booster tube.
At this moment we only have theoretical data regarding rocket mass and its
performance. We will be updating our mass statement as the data become available.
Deployment and Recovery
The rocket will use standard dual deployment technique for recovery. Two fully
independent PerfectFlite Stratologger altimeters will be used to fire the ejection charges.
Each altimeter will have its own power source, external arming switch and set of
charges. The primary drogue charge will be fired at apogee (5,482ft) and the backup
apogee charge will fire 1s after apogee. The main parachute will be deployed as field
conditions require to prevent excessive drift, most likely at 700ft with backup charge
following 200ft lower. The backup charges are 25% larger than primary charges. If the
primary charge succeeds, the backup charge fires harmlessly into open air.
Figure 1: Fully redundant recovery deployment
The table below shows the estimated parachute sizes, descent rates and landing impact
energy. As required, the rocket separates in no more than four tethered/independent
sections (3 tethered sections and a separate payload in our case) and the impact
energy is no more than 75ft-lbf for any of the parts (the impact energy for the entire
rocket is 37.9 ft-lbf).
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Madison West High School
Returning Team
SLI 2013 CDR
Parachutes
The table below shows the parachutes sizes, required ejection charges, descent rates
and impact energy.
Parachute Diameter
Descent
Ejection
Deployment
Descent
Impact Energy (ft-lbf)
(in)
Rate (fps)
Charge
Altitude (ft)
Weight
(g)
(lbs)
Drogue
18
56.75
.48
5034
4.6
N/A
Main
4
23.33
.81
700
4.6
Nose Cone: 5.37
Body: 9
Booster: 23.5
Table 1: Parachute sizes, ejection charges and descent rates
Load-bearing elements
We will use 3D printed rings and bulkheads. Each load-bearing bulkhead will be affixed
using at least equally spaced three screws and where possible, epoxy will be used to
further strengthen the point (this will not be possible with bulkhead that need to be
remove during rocket flight preparations).
The shockcords will be attached using QuickLinks and 1/4" stainless steel U-bolts. The
U-bolts will be installed through the bulkhead and secured with nuts on both side of the
bulkead. The entire assembly will be covered by a layer of thin epoxy to prevent
loosening of the nuts.
Where needed, stainless steel, #8 threaded rods will be use as tie-rods. Knurled knobs
will be used for tightening the tie-rods (to allow for tool-free adjustments).
The fins will be mount through-the-wall and anchored on the motor tube. Fillets will be
used at all place where the fin comes into contact with a tube (outer fillets on the motor
tube, inner and outer fillets on the body tube).
Drift
The following table shows the estimated drift of the rocket considering the descent rates
in the table above (total flight time 119s). As required the rocket will not drift past 2,500ft
at 15mph wind conditions.
Wind Speed (mph)
Drift (ft)
Drift (mi)
0
0
0
5
640
0.12
10
1280
0.24
15
1950
0.37
20
2625
0.49
Table 2: Drift distance
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Madison West High School
Returning Team
SLI 2013 CDR
Universal Avionics Platform - System Hermes
In order to speed-up development of our vehicles and payloads and to allow students to
spend more time on the experiments, during past few years students from Madison
West Rocketry have developed a universal and extensible payload-vehicle avionics
platform named Hermes (the winged messenger). Beginning with 2011/2012 school
year, system Hermes is being used in all Madison West Rocketry sounding rockets. The
system has been flight-tested during Rockets For Schools 2011 launch and successfully
used in our SLI 2012 projects.
System Hermes provides the following functionality out-of-box:
 Altitude and 3D acceleration data (100Hz, 8x oversampling, 12 or 16bit)
 Flight phases analysis (detects takeoff, burnout, staging, apogee, landing)
 Full duplex serial communication between rocket and ground (900MHz XBee)
 96KB of built-in memory for experimental data (expandable as needed)
 GPS location (transmitted to the ground station over wireless link)
 Telemetry link (for experimental data transmissions)
 Extension ports for payload controllers or other devices
 Regulated DC voltage to power other components (+5V, +3.3V)
In this season we intent to use the Hermes system to drive the payload operations and
to provide GPS tracking both for the payload and the vehicle. The system will not be
used for deployment purposes this year (we will continue to rely on proven PerfectFlite
StratoLogger altimeters).
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Madison West High School
Returning Team
SLI 2013 CDR
Vehicle Verification
Tested Components
• C1: Body (including construction techniques)
• C2: Altimeter
• C3: Accelerometer
• C4: Parachutes
• C5: Fins
• C6: Payload
• C7: Ejection Charges
• C8: Launch System
• C9: Motor Mount
• C10: Beacons
• C11: Shock Cords and Anchors
• C12: Rocket Stability
Verification Tests
• V1 Integrity Test: force applied; verifies durability
• V2 Parachute Drop Test: tests parachute functionality
• V3 Tension Test: force applied to shock cords; tests durability
• V4 Prototype Flight: tests feasibility of vehicle with scale model
• V5 Functionality Test: tests basic functionality of device on ground
• V6 Altimeter Ground Test: simulate altitude changes; verifies preset altitude
events fire
• V7 Electronic Deployment Test: tests that electronics ignite deployment
charges
• V8 Ejection Test: tests that deployment charges can deploy
parachutes/separate components
• V9 Computer Simulation: RockSim predicts behavior of launch vehicle
• V10 Integration Test: payload fits smoothly and snuggly into vehicle, and
withstands flight stresses.
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Madison West High School
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SLI 2013 CDR
Verification Matrix
V1
V2
V3
V4
V5
V6
V7
C1
C2
C3
C4
C5
C6
C7
C8
C9
C10
C11
C12
Status: the verification will start after the PDR teleconference.
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V8
V9
V10
Madison West High School
Returning Team
SLI 2013 CDR
Performance Targets that Apply to Vehicle
The following performance targets apply to the vehicle. These have been taken into
account:
1.1
1.3
1.4
1.5
1.6
1.7
1.8
1.9
1.10
1.11
1.13
1.14
1.15
1.17
Target altitude
Subsonic speed
Reusable vehicle
Maximum of 4 (four) separate sections
Maximum preparation time of 2 (two) hours
Minimum launch wait time of 1 (one) hour
Launch rail compatibility
12V launch system compatibility
No external launch circuitry
Commercially available solid propulsion
Maximum impulse of 2,560Ns
Maximum amount of ballast (10% of vehicle liftoff weight)
Test flights prior SLI launch in Huntsville
Vehicle prohibitions
All targets above are within defined constraints and will be satisfied as the project
progresses. USLI targets do not apply as we are a high school teams.
All performance targets are described in detail later in this document.
Vehicle-Payload Integration
Vehicle-payload integration is shown on the following picture.
Figure 2: Vehicle-payload integration
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Madison West High School
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SLI 2013 CDR
The payload is built in the booster section of the rocket. The air intakes for the onboard
wind tunnels are in the transition between upper (2.6”) and bottom (4.0”) section of the
vehicle. The air used in our experiments exits the rocket around the motor nozzle. Since
our payload is static (no moving parts), it will be only removed from the rocket for
maintenance and repairs. The payload can be tested before the flight inside the rocket.
Vehicle Launch Procedures
Vehicle launch procedures will be developed after the vehicle design is finalized in the
CDR cycle.
Vehicle Safety
Safety officer for the vehicle is Jack Roe. The detailed description of the vehicle safety
is included in our written Safety Plan at the end of this document.
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Madison West High School
Returning Team
SLI 2013 CDR
Payload Criteria
We will be investigating the effects of near sonic airspeeds on the behavior of sound
waves. We will build a high velocity miniature wind tunnel in our rocket on the basis of
the Bernoulli principle and de Laval nozzle. Intake tubes on the face of the rocket will
scoop air into tubes inside the rocket. The air will be accelerated to near sonic speeds
when it is funneled into a smaller chamber (de Laval nozzle). To compute airspeed
inside the nozzle we will use a Venturi tube arrangement, measuring static pressure at
the entrance, throat and exit from the nozzle.
Figure 3: Bernoulli Principle – the velocity of fluid increases as the fluid enters smaller tube or decreases when the fluid
enters larger tube (the total mass flow rate remains constant).
In our experiment we will use a de Laval nozzle to create near sonic speeds of the air
flowing through the nozzles. Whether the de Laval nozzle in our experimental setup can
create “choked flow” (speed of Mach 1.0) or supersonic exit speeds remains subject to
further research and experimentation. However, our experiment does not rely only on
these phenomena.
Current near sonic and supersonic wind tunnels have several severe limitations, namely
the costliness of building and powering such wind tunnels. Sustaining high wind speeds
takes immense amounts of power- about 50 MW per square meter of cross sectional
area. Some wind tunnels such as the Lugwieg tube use less power but can only
maintain supersonic wind speeds for a few seconds. By creating a near sonic wind
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Madison West High School
Returning Team
SLI 2013 CDR
tunnel in our rocket we propose an alternate, low-cost option for research of fluid
behavior at very high speeds.
The basic unit of our experiment is an instrumented de Laval nozzle. At both ends of the
nozzle is a microphone with a recording device for registering sound. In the throat of the
nozzle is a sound generator (strong piezo beeper) that will emit short loud sound pulses
at regular intervals. Three pressure sensors will measure static pressure in the nozzle:
one at the entrance, another in the throat and the last in the exit portion of the nozzle.
The readings from the pressure sensors will be used to determine the velocity of moving
fluid (air). The drawing of the instrumented nozzle is on the figure below:
Figure 4: Instrumented de Laval nozzle with sound generator in the middle, microphones at both ends and pressure
sensors near the throat entrance, in the throat and in the exit portion.
The sound pulses will be emitted at regular intervals and the microphones will record
the sounds as it arrives. We expect to see volume change up to a possible absence of
the sound on the upstream end as the speed of fluid approaches Mach 1. Because both
the sound source (beeper) and the sound observers (microphones) are stationary, we
should not observe frequency change due to a Doppler effect.
Our vehicle will house the payload in its bottom part (entire recovery system is in the
upper part of the vehicle). The payload will consists from 2-4 instrumented de Laval
nozzles to provide redundancy in data collection should one or more of experimental
units of them of them fail. We are also considering the possibility of modifying some of
the nozzles (for example using smaller or larger throat diameter) and comparing the
results.
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Madison West High School
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SLI 2013 CDR
The following picture shows how the payload is integrated in the bottom section of our
rocket.
Figure 5: Payload vehicle integration. Air enters through the intakes in conical transition, flows through the instrumented
de Laval nozzles and exits through the bottom of the rocket, around the motor.
The payload resides in the bottom section of the rocket, right above the motor mount.
The air feeding the de Laval nozzles enters through openings in the conical transition,
flows through the de Laval nozzles inside the rocket and exits the rocket via exhaust
vents around the motor tube. Since the entire recovery system resides in the upper part
of the rocket, there is no interference between payload and recovery. There is also no
interference with the motor or fins.
Experimental sequence is as follows:
Figure 6: Experimental sequence: 1) rocket launches and G-switch activates the payload 2) Air rushes through the de
Laval nozzles in the payload, sound generators send sound pulses recorded by microphones 3) When rocket reaches
apogee, the drogue parachute is deployed and data recording ends; finally the rocket deploys main parachute at 700ft and
lands safely.
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Madison West High School
Returning Team
SLI 2013 CDR
Selection, Design and Verification of Payload Experiment
Measurements
The entire experiment lasts only 20 seconds with the most interesting period (when the
“choked flow” condition may develop and the airspeed inside de Laval nozzle will reach
Mach 1.0) being only a few seconds. The pressure sensors can react to changes in a
pressure within 1ms. We will emit a sound pulse every 10ms, thus emitting 100 pulses a
second while sampling and recording all measured quantities 1000 times a second.
Data and Correlations
The following quantities will be measured and/or recorded:
Independent Variables
v
Rocket velocity
Constants
A0
t0
c0
f0
Volume of emitted sound pulses
Time interval between emitted sound pulses
Total count of all pulses emitted
Frequency of generated sound
Dependent Variables
w
Au
Ad
tu
td
cu
cd
Velocity of fluid (air) at the throat of de Laval nozzle
Volume of sound pulses recorded upstream
Volume of sound pulses recorded downstream
Time interval between recorded pulses upstream
Time interval between recorded pulses downstream
Total count of pulses recorded upstream
Total count of pulses recorded downstream
w
will be computed from pressure difference measured by the three
pressure sensors
Primary Correlations
w
= f(v) air speed in nozzle throat as it depends on rocket speed
Au, Ad = f(w) Volume change of recorded pulses as function of airspeed
tu, td = f(w) Interval between arriving pulses as function of airspeed
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Madison West High School
Returning Team
SLI 2013 CDR
Hypotheses
We make the following hypotheses:
1) No matter how high the rocket’s speed (always subsonic) will be, the speed in
the nozzle throat will approach but not exceed Mach 1 (choked flow condition)
2) We expect the volume of pulses recorded downstream be higher than the volume
of pulses recorded upstream
3) We expect the time interval between recorded pulses remain same as the
interval at which pulses are emitted
4) We expect the downstream count of pulses be the same as the count of pulses
emitted
5) Assuming the “choked flow” phenomena develops in the nozzle; we expect the
upstream pulse count to be less than the count of emitted pulses. We may also
lose pulses upstream if their volume drops below recordable level.
6) Since both the sound emitter and sound receivers are stationary, in their frame of
reference, we should NOT observe frequency change (Doppler effect).
Post Flight Procedure
After a successful flight and rocket/payload recovery, we will download the data from
the payload. The data will be analyzed as described in Data Analysis Section and the
final report (PLAR) will be compiled and submitted to NASA.
Payload Concept Feature and Definitions
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Madison West High School
Returning Team
SLI 2013 CDR
Payload Verification
Components to verify
 C1: Speakers
 C2: Microphones
 C3: Electronics
 C4: De Laval nozzle
 C5: Air Intake (transition)
 C6: Air Exhaust
Tests to Apply
• V1: Basic Function Test- testing the main functions of the payload
• V2: Leak Test- verifying that the vessels containing the air do not leak
• V3: Vehicle Safety and Integrity Test:-Verify that the component does not
interfere with the function of the rocket
Verification Matrix
C1
C2
C3
C4
C5
C6
V1
V2
V3
Table 3: Payload verification matrix
Status: the verification will start after the PDR teleconference.
Payload Safety
The payload safety officer is Adrian Guither. The detailed discussion of payload safety
is included in the written Safety Plan section at the end of this document.
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Madison West High School
Returning Team
SLI 2013 CDR
Safety
Written Safety Plan
I. NAR Safety Requirements
a. Certification and Operating Clearances: Mr. Lillesand holds a Level 3 HPR
certification. Dr. Pinkas has a Level 1 HPR certification and plans on having a Level 2
HPR certification by the end of February 2013. Mr. Guither holds a level 1 HPR
certification. He plans to complete his Level 2 by April 2013 and is our back-up launch
supervisor. Mr. Lillesand has Low Explosives User Permit (LEUP). If necessary, the
team can store propellant with Mr. Goebel, who owns a BATFE approved magazine for
storage of solid motor grains containing over 62.5 grams of propellant.
Mr. Lillesand is the designated individual rocket owner for liability purposes and he will
accompany the team to Huntsville. Upon their successful L2 certification, Mr. Guither
and Dr. Pinkas will become a backup mentors for this role.
All HPR flights will be conducted only at launches covered by an HPR waiver (mostly
the WOOSH/NAR Section #558 10,000ft waiver for Richard Bong Recreation Area
launch site). All LMR flights will be conducted only at the launches with the FAA
notification phoned in at least 24 hours prior to the launch. NAR and NFPA Safety
Codes for model rockets and high power rockets will be observed at all launches.
Mentors will be present at all launches to supervise the proceedings.
b. Motors: We will purchase and use in our vehicle only NAR-certified rocket motors
and will do so through our NAR mentors. Mentors will handle all motors and ejection
charges.
c. Construction of Rocket: In the construction of our vehicle, we will use only proven,
reliable materials made by established manufacturers, under the supervision of our
NAR mentors. We will comply with all NAR standards regarding the materials and
construction methods. Reliable, verified methods of recovery will be exercised during
the retrieval of our vehicle. Motors will be used that fall within the NAR HPR Level 2
power limits as well as the restrictions outlined by the SLI program. Lightweight
materials such as fiberglass tubing and carbon fiber will be used in the construction of
the rocket to ensure that the vehicle is under the engine’s maximum liftoff weight. The
computer programs RockSim and Open Rocket will be utilized to help design and pretest the stability of our rocket so that no unexpected and potentially dangerous problems
with the vehicle occur. Scale model of the rocket will be built and flown to prove the
rocket stability.
d. Payload: As our payload does not contain hazardous materials, it does not present
danger to the environment. However, our NAR mentors will check the payload prior to
launch in order to verify that there will be no problems.
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Madison West High School
Returning Team
SLI 2013 CDR
e. Launch Conditions: Test launches will be performed at Richard I. Bong Recreation
Area with our mentors present to oversee all proceedings. All launches will be carried
out in accordance with FAA, NFPA and NAR safety regulations regarding model and
HPR rocket safety, launch angles, and weather conditions. Caution will be exercised by
all team members when recovering the vehicle components after flight. No rocket will be
launched under conditions of limited visibility, low cloud cover, winds over 20mph or
increased fire hazards (drought).
II. Hazardous Materials
All hazardous materials will be purchased, handled, used, and stored by our NAR
mentors. The use of hazardous chemicals in the construction of the rocket, such as
epoxy resin, will be carefully supervised by our NAR mentors. When handling such
materials, we will make sure to carefully scrutinize and use all MSDS sheets and
necessary protection (gloves, goggles, proper ventilation etc.).
All MSDS sheets and federal/state/local regulation applicable to our project are
available online at
http://westrocketry.com/sli2013/safety/safety2013r.php
III. Compliance with Laws and Environmental Regulations
All team members and mentors will conduct themselves responsibly and construct the
vehicle and payload with regard to all applicable laws and environmental regulations.
We will make sure to minimize the effects of the launch process on the environment. All
recoverable waste will be disposed properly. We will spare no efforts when recovering
the parts of the rocket that drifted away. Properly inspected, filled and primed fire
extinguishers will be on hand at the launch site.
Cognizance of federal, state, and local laws regarding unmanned rocket launches
and motor handling
The team is cognizant and will abide with the following federal, state and local laws
regarding unmanned rocket launches and motor handling:

Use of airspace: Federal Aviation Regulations 14 CFR, Subchapter F, Part 101,
Subpart C

Handling and use of low explosives: Code of Federal Regulation Part 55

Fire Prevention: NFPA1127 Code for High Power Rocket Motors
All of the publications mentioned above are available to the team members and mentors
via links to the online versions of the documents.
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Madison West High School
Returning Team
SLI 2013 CDR
http://westrocketry.com/sli2013/safety/safety2013r.php
WRITTEN STATEMENT OF SAFETY REGULATIONS COMPLIANCE
All team members understand and will abide by the following safety regulations:
a. Range safety inspections of each rocket before it is flown. Each team shall comply
with the determination of the safety inspection.
b. The Range Safety Officer has the final say on all rocket safety issues. Therefore, the
Range Safety Officer has the right to deny the launch of any rocket for safety
reasons.
c. Any team that does not comply with the safety requirements will not be allowed to
launch their rocket.
IV. Education, Safety Briefings and Supervision
Mentors and experienced rocketry team members will take time to teach new members
the basics of rocket safety. All team members will be taught about the hazards of
rocketry and how to respond to them; for example, fires, errant trajectories, and
environmental hazards. Students will attend mandatory meetings and pay attention to
pertinent emails prior participation in any of our launches to ensure their safety. A
mandatory safety briefing will be held prior each launch. During the launch, adult
supervisors will make sure the launch area is clear and that all students are observing
the launch. Our NAR mentors will ensure that any electronics included in the vehicle are
disarmed until all essential pre-launch preparations are finished. All hazardous and
flammable materials, such as ejection charges and motors, will be assembled and
installed by our NAR-certified mentor, complying with NAR regulations. Each launch will
be announced and preceded by a countdown (in accordance with NAR safety codes).
V. Procedures and Documentation
In all working documents, all sections describing the use of dangerous chemicals will be
highlighted. Proper working procedure for such substances will be consistently applied,
such as using protective goggles and gloves while working with chemicals such as
epoxy. MSDS sheets will be on hand at all times to refer to for safety and emergency
procedures. All work done on the building of the vehicle will be closely supervised by
adult mentors, who will make sure that students use proper protection and technique
when handling dangerous materials and tools necessary for rocket construction.
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Madison West High School
Returning Team
SLI 2013 CDR
Physical Risks
Risks
Saws, knives,
Dremel tools,
band saws
Sandpaper,
fiberglass
Drill press
Consequences
Laceration
Mitigation
All members will follow safety procedures
and use protective devices to minimize risk
Abrasion
Soldering iron
Burns
Computer,
printer
Workshop risks
Electric shock
All members will follow safety procedures
and use protective devices to minimize risk
All members will follow safety procedures
and use protective devices to minimize risk
All members will follow safety procedures to
minimize risk
All members will follow safety procedures to
minimize risk
All work in the workshop will be supervised
by one or more adults. The working area will
be well lit and strict discipline will be required
Puncture wound
Personal injury,
material damage
Table 4: Risks that would cause physical harm to an individual
Toxicity Risks
Risks
Epoxy, enamel
paints, primer,
superglue
Superglue,
epoxy, enamel
paints, primer
Consequences
Toxic fumes
Toxic substance
consumption
Mitigation
Area will be well ventilated and there will be
minimal use of possibly toxic-fume emitting
substances
All members will follow safety procedures to
minimize risk. Emergency procedure will be
followed in case of accidental digestion.
Table 5: Risks that would cause toxic harm to an individual
Scheduling and Facilities Risks
Risks
Workshop
space
unavailable
Design facilities
unavailable
Consequences
Unable to complete
construction of
rocket and/or
payload
Unable to complete
project
Team members Unable to complete
unavailable
project
Mitigation
We will insure the availability of our
workshop space for the times that we need
it. We will also work at team members’
homes if necessary.
We will insure the availability of our design
facilities and work at team members’ homes
if needed.
We will plan meetings in advance and insure
that enough team members will be present
to allow sufficient progress.
Table 6: Scheduling risks that would inhibit our progress on our project
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Madison West High School
Returning Team
SLI 2013 CDR
Rocket/Payload Risks
Risks
Consequences
Unstable rocket Errant flight
Improper motor
mounting
Damage or
destruction of
rocket.
Weak rocket
structure
Propellant
malfunction
Rocket structural
failure
Engine explosion
Parachute
Parachute failure
Payload
Payload
failure/malfunction
Errant flight
Launch rail
failure
Separation
failure
Parachutes fail to
deploy
Ejection falsely
triggered
Unexpected or
premature
ignition/personal
injury/property
damage
Rocket is lost
Recovery
failure
Transportation
damage
Possible
aberrations in
launch, flight and
recovery.
Mitigation
Rocket stability will be verified by computer
and scale model flight.
Engine system will be integrated into the
rocket under proper supervision and used in
the accordance with the manufactures’
recommendations.
Rocket will be constructed with durable
products to minimize risk.
All members will follow NAR Safety Code for
High Powered Rocketry, especially the safe
distance requirement. Attention of all launch
participants will be required. Mentors will
assemble the motors in accordance with
manufacturer's instructions.
Parachute Packaging will be double checked
by team
members.
Deployment
of
parachutes will be verified during static
testing.
Team members will double-check all
possible failure points on payload.
NAR Safety code will be observed to protect
all member and spectators. Launch rail will
be inspected prior each launch.
Separation joints will be properly lubricated
and inspected before launch. All other joints
will be fastened securely.
Proper arming and disarming procedures will
be followed. External switches will control all
rocket electronics.
The rocket will be equipped with radio and
sonic tracking beacons.
Rocket will be properly packaged for
transportation and inspected carefully prior
to launch
Table 7: Risks associated with the rocket launch
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Madison West High School
Returning Team
SLI 2013 CDR
Educational Engagement
Outreach Programs
Each year we participate in many educational engagement opportunities, such as
helping sizeable groups of young children at the local middle schools to build and fly
Alka-Seltzer powered rockets. We launched about 300 rockets for an audience of about
150 kids during this program, as well as displaying some of our TARC, SLI and R4S
rockets.
We are currently participating in our annual “Raking for Rockets” program, where we
rake community lawns in order to simultaneously bring about an increased awareness
in rocketry, and raise the funds necessary for our TARC and SLI programs.
Figure 7: Poster advertising our yardwork services. The yardwork fundraisers are one of our major income sources and
also greatly increase the visibility of our program in the community.
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Madison West High School
Returning Team
SLI 2013 CDR
Besides these programs, we also recruited new members for our club at Madison West
High School (our current membership is above 50 students mark) in a number of
recruitment events which included the daily announcements, organized recruitment
events, and posters throughout the school advertising the location and time of the first
informational meeting. The new members will participate in TARC, along with a few
returning members from our SLI teams. TARC club meetings provide interested new
members learning about the basics of rocket design, building, and operation.
The table below shows the outreach programs that plan for this year. The programs
target primarily elementary and middle schools. We will most likely add several events
to this program as the year progresses (we have become well known for our outreach
activities and we are already receiving requests from schools and organization that we
have never worked with before).
Date
School
Outreach
Sept. 28, 2012
Randall Elementary
Dec. 8, 2012
Eagle Elementary
Jan 26, 2013
Lincoln Elementary
Feb. 15, 2013
O’Keefe Middle
School
Mar. 9, 2013
Randall Elementary
Apr. 13, 2013
Lincoln Elementary
School
Homecoming
Parade
Alka-Seltzer
Rockets
Alka-Seltzer
Rockets
Super Science
Saturday (AlkaSeltzer Rockets)
Super Science
Saturday
(Alka-Seltzer
Rockets)
Pneumatic Rockets
Table 8: Planned outreach events.
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# of People
(estimate)
100
50
50
50
100
50
Total: 450
Madison West High School
Returning Team
SLI 2013 CDR
Project Plan
Schedule
1
31
27
30
4
11
22
29
5
7-16
10
24-25
3
8-9
10
15-16
24-31
12-13
14
19-20
23-Feb. 1
2-3
9-10
11
23-24
8-9
15-16
18
AUGUST 2012
Request for Proposal (RFP) goes out to all teams
SLI Proposal due to NASA (electronically)
SEPTEMBER 2012
Schools notified of selection
PDR work begins
OCTOBER 2012
Team teleconference
Preliminary Design Review (PDR) question and answer session
Web presence established for each team
PDR reports, presentation slides, and flysheet posted on team website by
8am C.T.
NOVEMBER 2012
Acquire parts for subscale model and payload prototype
PDR Presentations
Subscale model construction begins
Payload design reviews
DECEMBER 2012
Critical Design Review (CDR) question and answer session
Subscale model ejection tests, test flights, flight data analysis
Acquire parts and supplies for full scale vehicle construction
Full scale vehicle construction begins
Winter break
JANUARY 2013
Full scale vehicle construction completed
CDR reports presentation, and flysheet posted on team website by 8am
C.T.
Full scale vehicle half impulse test flight, flight data analysis
CDR presentations
FEBRUARY 2013
Payload construction begins
Full scale vehicle revisions for full impulse test flight
Flight Readiness Review (FRR) question and answer session
Full scale vehicle full impulse flight, flight data analysis
MARCH 2013
Payload progress review
Payload construction completed
FRR reports presentation, and flysheet posted on team website by 8am
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Madison West High School
23-24
25- Apr. 3
6-7
13-14
17
18-19
20
21
6
17
Returning Team
SLI 2013 CDR
C.T.
Full scale vehicle with payload test flight, flight/payload data analysis
Flight Readiness Review presentation
APRIL 2013
Final vehicle and payload adjustments
Packing for trip to Huntsville, AL
5pm all teams arrive in Huntsville, AL
5:30pm Team lead meeting
6:30pm Launch Readiness Reviews (LRR) begins
Welcome to MSFC/LRR continue
Launch Day
Launch Day Rain Day
MAY 2012
Post-Launch Assessment Review (PLAR) posted on the team website by
8:00 a.m. Central Time
Winning USLI team announced
Table 9: Timeline of SLI 2013
The schedule is subject to changes as the launch windows for 2013 are not confirmed
yet (the schedule shows our best estimate based on the launch site schedule from
previous years).
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Madison West High School
Returning Team
SLI 2013 CDR
Budget
Vehicle
Tubing, nosecone, bulkheads, rings
Fin Material (G10 Fiberglass)
Paint and Primer
PerfectFlite StratoLogger Altimeter
(x 2)
Motor Retention
Parachutes, recovery gear
Epoxy
Walston Beacon
GPS
Miscellaneous supplies (tools,
batteries, wires, hardware)
$200.00
$100.00
$50.00
$200.00
$50.00
$100.00
$100.00
$150.00
$100.00
$200.00
Scale Model
Paper Tubing
Parachute and shock cords
Fin Material (G10 Fiberglass)
$150.00
$100.00
$ 50.00
Motors
Scale Model Motors
Full Scale Test Flight Motors
$50.00
$ 350.00
Payload
Main Computer
G sensor
Pressure Sensors
Beepers, microphones
Accelerometer, GPS
3D printing supplies
$ 200.00
$ 10.00
$100.00
$100.00
$200.00
$ 300.00
Total
$ 2,860.00
Table 10 : Budget for 2012-13 SLI Program (* - already in possession)
Flight
$400/Person * 11 People
$4,400.00
Rooms
$119/Room * 6 Rooms * 5 Nights
$2,975.00
Car Rental (Ground Support Vehicle)
$500 rental+ $600 gas
$1100.00
Total
$8,475.00
Cost per Team Member
$
Table 11: Budget for the travel to Huntsville, AL
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941.67
Madison West High School
Returning Team
SLI 2013 CDR
Madison West Rocket Club has sufficient money earning opportunities (raking
leaves/yardwork, donations from families or mentors) to cover for possible
discrepancies between the estimated budget and actual project expenses. Additionally,
it is our policy to provide necessary economic help to all SLI students who cannot afford
the travel expenses associated with the program. Every year we award several full
expense travel scholarships both to our SLI and TARC students. The monetary
amounts and the names of recipients are not disclosed.
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