Solid Rocket Experiment ARO 102L Introduction of Astronautics Try Lam

Burn Coast Descent Mission Profile

Solid-Fueled Rocket Performance Project Objective: This project is intended to provide a basic introduction to the mechanics of rocket flight theory and experimentation with solid-fuel model rocket. Three Phases 1.Static ground test 2.Assemble the rocket in class 3.Flying and flight measurement Groups: You will split into groups of 5 to 6. Each group will analytically predict the time it takes for each of the group’s rockets (5 or 6 rockets) to ascent, deploy their parachutes, and return to the ground. Equipment: NANO or Nimbs model rocket kit Estes A8-3 solid-propellant model rocket engine Assembly tools Measuring tools Stopwatch Launch pad

Solid-Fueled Rocket Performance Project Procedures

Solid-Fueled Rocket Performance Project Rocket Assembly Carefully read and follow the instructions in the rocket kit! Procedures

Solid-Fueled Rocket Performance Project Measurements Measure the body tube diameter for drag estimation. Record the nose code shape for C D value. With the unburned rocket engine temporarily installed in your rocket, measure the Rocket mass Center of gravity location (form nose tip) Calculate the parachute’s drag coefficient by dropping the rocket with the parachute open Find a two story building and drop your rocket off with the parachute deployed. Measure the height dropped and the time it takes to fall. Measure the effective diameter of the parachute Compute the C D_para (below) Procedures where

Solid-Fueled Rocket Performance Project Pre-Flight Operational Checks Make sure that the nose cone can easily slip out of the body tube Make sure the parachute is not tangles up (might want to add some baby powder to the parachute to ensure it doesn't stick or tangle). Team Assignments Rocket launcher = the owner of the rocket Record the mass before and after launch Place rocket on launch pad (note which channel it is on) Go to the launch table Arm the launch system Loudly count down “3-2-1-fire” Push the igniter button Timers (x2) Stand at sides of the launch area Start timing when they here “fire” command Record the time at maximum altitude and time to ground Procedures

Solid-Fueled Rocket Performance Project Team Assignments (continues) Inclinometer (x2) Practice this before actual flight Stand 50 yards away form the launch stand Point the inclinometer at the rocket on the stand and pull the trigger to unlock the pendulum pointer. Follow the rocket’s flight path pointing the inclinometer like a gun sight When the rocket reaches maximum altitude, the trigger will be released, locking the inclinometer pointer at max inclination angle. Record the angle Procedures

Solid-Fueled Rocket Performance Project Inclinometer & Altitude Calculation

Solid-Fueled Rocket Performance Project Pre-Flight Operational Checks Make sure that the nose cone can easily slip out of the body tube Make sure the parachute is not tangles up (might want to add some baby powder to the parachute to ensure it doesn't stick or tangle). Launch Operations See “Team Assignments” Record the time to max altitude Record the total time (launch to ground) Record data from the inclinometer (max inclination) Procedures

Solid-Fueled Rocket Performance Project Engineering Calculations Calculate how high (in meters) the rocket is expected to fly based on your measured mass and the published or measured characteristics of the A8-3 engine being used, and how long it will take to get to the max altitude. You will have to estimate the drag coefficient of your rocket. Use the experimental drag coefficient graph, consider your rocket’s shape, have the fins been streamlined, shape of the nose cone, launch lug drag, etc. From the Estes A8-3 model rocket engine specs, the rocket has a burn time of t B = 0.73 sec, average T = 3.18 N, and a burnout mass of 10.2 g, total impulse = 2.5 Ns. Write down yours Post Launch Calculations SpecsReported ValuesYour ValuesComments Burn Time, t B 0.73 secs Average Thrust, T3.18 N Burn out mass10.2 gEngine only Total Impulse, I total 2.5 NsItotal = Σ (T × Δt )

Graph from “Model Rocket Altitude Performance”, Centuri Engineering Technical Information Report TIR- 100, 1968

Solid-Fueled Rocket Performance Project Engineering Calculations Compute the total altitude (see “Useful Equations” slide) Compute the total descent time (see “Useful Equations” slide) Compute the total flight time (see “Useful Equations” slide) Compare calculated results to recorded results Post Launch Calculations

Solid-Fueled Rocket Performance Project General Each is group is to turn in a TYPED report with everyone’s data Cover Page Include course name, section number, experiment name, quarter, date Include group number and names of the group members Summary Page Include objective Include key objective Include a brief conclusion Include something like the table below Report Membe r Name Sanded Fin? Predicted Time to Max Alt. (s) Measured Time to Max. Alt. (s) % Error for time to Max. Alt. Predicted Max. Alt. (m) Measured Max. Alt. (m) [inclinomet er) % Error for Max. Alt. Predicted Total Flight Time (s) Measured Total Flight Time (s) % Error of Total Flight Time Parachute Open? BobYes5620%5055………5%No SueNo67…………………Yes

Solid-Fueled Rocket Performance Project Rocket Description Page(s) Include description of rocket, manufacturers, model, and engine type Include pictures, photos, diagrams, and describe the assembly process. Launch System Description Page(s) Include description of launch system, platform, guide rods, and launch equipment Include pictures, photos, diagram Include a description of the launch process Described the launch mission profile Include details of what you recorded Parachute Pre-Launch Test Description Page(s) Include description of parachute pre-launch test and the purpose of this test Include pictures, photos, or diagram of what you did Include equations and results form all member’s rockets (their C d_para value, etc.) Report

Solid-Fueled Rocket Performance Project Static Engine Ground Pre-Launch Test Description Page(s) Include description of static engine ground test and the purpose of this test Include pictures, photos, or diagram of what you did Include equations and results form the ground test (e.g., the Isp values, thrust vs. time plots) Maximum Altitude Measurement Page(s) Include description of the inclinometer device and the measurement technique Include table and equations describing the conversion form recorded angle to altitude Include photos, diagram, or pictures if you want Discuss if wind conditions affected your measurements Other Measurement Page(s) Include description and discussion of any other measurements (if any) Report

Solid-Fueled Rocket Performance Project Calculation Page(s) Include equations, discussions, and results Include table of measurements, calculations, and errors Discuss anything that might be an error source or what might affect your results Conclusion Page(s) Summarize the experiment, what you can do better, lessons learned, etc. References Appendix Any raw data, tables, notes, equations you want to include Report

Useful Equations General Equations Thrusting (Burnout) Equations

Useful Equations Coasting Equations Coast + Thrust Altitude Equation Descent Equations

Table of Results ItemSymbolValuesUnits Center of Gravity LocationX cg Empty Mass of Rocketm rocket Liftoff Mass of Rocketm Pre-launch Motor Massm motor Gravityg Liftoff WeightW Drag CoefficientCDCD Diameter of Rocketd Cross Section AreaA Field Elevationh Air Density (at elevation)ρ Engine TypeEstes A8-3 Average ThrustT Burn Timetbtb Propellant Massm prop Specific ImpulseI sp

Table of Results ItemSymbolValuesUnits Thrusting and Coasting Calculations Burnout VelocityVBVB Burnout AltitudehBhB Coast AltitudehChC Coast TimetCtC Total Altitudeh total Parachute Descent Calculations Parachute Diameterd para Parachute AreaA para Drop Time (pre-flight)t drop Drop Distance(pre-flight)h drop Parachute Descent VelocityV para Parachute Drag CoefficientC D_para Descent Timet descent Total Flight Timet total

Table of Results ItemSymbolValuesUnits Performance Calculations Exhaust Gas VelocityVeVe ΔV = V e ln(m initial /m final )ΔV ItemSymbolValuesUnits Compare Calculation to Test Data Total Altitude (calculated)h total_calc Total Altitude (recorded)h total_data % difference (error)Error alt Total Flight Time (calc.)t total_calc Total Flight Time (record.)t total_data % difference (error)Error time

Appendix Model Rocket Assembly Instructions

Model Rocket Engine

Model Rocket