Rocket Cert Prep

Tripoli L2

Study guide

All 108 questions with answers and rationale.

108 of 108

  1. #1Which of Newton's Laws best describes the behavior of a rocket motor?

    Newton's Laws
    1. A)Newton's First Law: A body continues in its state of rest or of uniform motion in a straight line unless it is compelled to change that state by forces impressed upon it
    2. B)Newton's Second Law: The rate of change of momentum is proportional to the force impressed and is in the same direction as that force
    3. C)Newton's Third Law: To every action there is always an equal and opposite reactionCorrect

    Why: Newton's Third Law. Applying a force in one direction always results in an equal force in the opposite direction.

  2. #2How does Newton's Third Law "To every action there is always an equal and opposite reaction" relate to rocketry?

    Newton's Laws
    1. A)That the blast deflector must be strong enough to push the rocket off the launch pad at ignition.
    2. B)That a rocket flies because the rocket motor "pushes" the rocket in a direction opposite of the exhaust jet.Correct
    3. C)That the thrust of a rocket motor is proportional to the air density at the launch site

    Why: The rocket motor's thrust causes the rocket to accelerate in the direction opposite the motor's thrust. Thus, a rocket motor pushes only on the rocket, not on the air or launch pad.

  3. #3What are the three forces acting upon a rocket during flight?

    Forces & Altitude
    1. A)Thrust, rocket diameter and finish
    2. B)Nose cone shape, thrust and drag
    3. C)Gravity, thrust and aerodynamic dragCorrect

    Why: Gravity, thrust and drag are the forces acting on a rocket.

  4. #4What are the three major factors that determine the maximum altitude of a high-power rocket in vertical flight?

    Forces & Altitude
    1. A)Lift-off weight, propellant weight and motor thrust
    2. B)Fin size, propellant weight and motor thrust
    3. C)Motor thrust, rocket weight, and aerodynamic dragCorrect

    Why: The motor thrust, weight and aerodynamic drag are the primary forces considered when determining the altitude of a rocket. Both the lift-off weight and the weight at burn-out must be considered to be complete.

  5. #5For an inherently stable rocket, which statement about the center of gravity (CG) and the center of pressure (CP) is true?

    Stability (CG/CP)
    1. A)The CG must be behind the CP relative to the desired direction of flight
    2. B)The CG must be forward of the CP relative to the desired direction of flightCorrect
    3. C)The CG must move forward (in the desired direction of flight) during the motor burn

    Why: For an aerodynamically stable rocket with the CP behind the CG, the lift centered aft of the CG creates a corrective moment that returns the rocket to zero degrees angle of attack.

  6. #6A 4" diameter rocket with its motor is determined to have the center of gravity (CG) four inches behind the center of pressure (CP). Is this a rocket likely to be stable?

    Stability (CG/CP)
    1. A)No, the CG should be at least two body diameters behind the CP
    2. B)No, the CP must be behind the CG for the rocket to be stableCorrect
    3. C)Yes, the CP is one body diameter in front of the CG

    Why: The rocket is not stable. If rotated around its CG, the aerodynamic force forward of the CG would cause it to rotate even farther, resulting in unstable flight.

  7. #7The center of pressure (CP) of a rocket is generally defined as:

    Stability (CG/CP)
    1. A)The balance point of the rocket without the motor
    2. B)The total area of the fins, airframe and nose cone divided by two
    3. C)The point at which aerodynamic lift on a rocket is centeredCorrect

    Why: The center of pressure (CP) is the point on the rocket where aerodynamic lift is centered.

  8. #8What is the "rule-of-thumb" for a stable rocket?

    Stability (CG/CP)
    1. A)That the center of gravity should be at least one body diameter in front of the center of pressureCorrect
    2. B)That the center of gravity should be very nearly at the same point as the center of pressure
    3. C)The rocket should balance near or at the center of gravity

    Why: Keeping the CG one body diameter in front of the CP typically allows an adequate margin for rocket stability.

  9. #9You are at the launch site and decide to fly your rocket on a heavier motor than you simulated it on. Which statement regarding CG is true?

    Stability (CG/CP)
    1. A)One can install the motor, recovery system and payload and determine the balance point of the rocket as it is ready for flightCorrect
    2. B)One can balance the rocket with the motor hardware alone because that is the condition of the rocket after motor burnout
    3. C)It is not necessary to test for the center of gravity when using a heavier motor because it has more thrust

    Why: Measuring the CG by balancing the rocket requires that the rocket be prepared as though ready for flight. It is especially important to check when using a heavier motor than previously flown.

  10. #10What ordinarily happens to the center of gravity (CG) of a rocket during a solid rocket motor's thrusting phase?

    Stability (CG/CP)
    1. A)The CG stays the same
    2. B)The CG shifts forwardCorrect
    3. C)The CG shifts aft

    Why: As the propellant burns, the motor gets lighter causing the CG to shift forward. This is why a marginally stable rocket may "act squirrelly" at launch, then stabilize and fly straight.

  11. #11How can a statically unstable rocket be made stable?

    Stability (CG/CP)
    1. A)Using a heavier motor
    2. B)Adding weight to the noseCorrect
    3. C)Making the rocket shorter

    Why: Adding enough weight to the nose will shift the CG forward of the CP.

  12. #12What are three methods used to shift the center of gravity (CG) of a rocket forward?

    Stability (CG/CP)
    1. A)Add weight to the nose, make the rocket longer, install larger fins
    2. B)Add weight to the nose, make the rocket longer, use a smaller (or lighter) motorCorrect
    3. C)Add weight to the nose, make the rocket shorter, use a smaller motor

    Why: Adding mass to the nose, making the rocket longer ahead of the CP (lever-arm), and using a lighter motor all shift the CG forward.

  13. #13What are three methods used to shift the center of pressure (CP) aft?

    Stability (CG/CP)
    1. A)Make the rocket shorter, use larger fins, increase the number of finsCorrect
    2. B)Make the rocket shorter, use smaller fins, add weight to the nose
    3. C)Make the rocket shorter, change the number of fins, use a longer launch rod

    Why: Increasing the total fin area moves the CP aft. This can be done with larger fins or more fins. Shortening the rocket ahead of the CP also moves CP aft (though this also moves CG aft).

  14. #14The definition of coefficient of drag (Cd) is:

    Drag
    1. A)A dimensionless number that represents the effect of gravity and Mach number of the rocket
    2. B)A dimensionless number dependent on the rocket configuration, Mach number and angle of attackCorrect
    3. C)The force, in Newtons, exerted on the rocket by the atmosphere

    Why: Cd is a dimensionless number used in equations for aerodynamic drag. It depends on nose cone shape, airframe diameters, transitions, fin size/shape, Mach number, and angle of attack.

  15. #15What happens to the coefficient of drag (Cd) as the rocket approaches the speed of sound?

    Drag
    1. A)The Cd decreases
    2. B)The Cd stays the same
    3. C)The Cd increases.Correct

    Why: Cd increases and can be greater than 1 as the rocket exceeds Mach 1.

  16. #16For a subsonic rocket, what factors most greatly affect the coefficient of drag (Cd)?

    Drag
    1. A)Motor thrust, body diameter, nosecone shape and fin shape
    2. B)Speed, airframe dimensions, nosecone shape and fin shapeCorrect
    3. C)Gravity, airframe dimensions, nosecone shape and fin shape

    Why: As speed increases, the drag number changes. Length and diameter affect surface area; nose cone shape affects airflow over the front; fin shape and area factor into total surface area.

  17. #17What effect does a boat tail have on a subsonic rocket's coefficient of drag (Cd)?

    Drag
    1. A)No effect, a boat tail is only a cosmetic design feature
    2. B)It increases the Cd by changing the airflow over the fins
    3. C)It decreases the Cd by reducing the base dragCorrect

    Why: A boat tail reduces drag for a subsonic rocket by reducing the base drag from the discontinuity of the air flow as it leaves the end of the rocket.

  18. #18The flight of a high-power rocket can be separated into three portions; they are:

    Flight Phases
    1. A)Ignition, burnout and peak altitude
    2. B)Powered flight, un-powered ascent and peak altitude
    3. C)Powered flight, un-powered ascent and descentCorrect

    Why: (1) Powered flight – motor producing thrust against gravity and drag; (2) Un-powered ascent – coasting to peak altitude, affected by gravity and drag; (3) Descent – return to Earth.

  19. #19Which describes the thrust curve of a regressive motor burn?

    Motor Characteristics
    1. A)A high initial thrust relative to the ending thrust of the motorCorrect
    2. B)A lower initial thrust relative to the ending thrust
    3. C)The thrust curve is flat

    Why: As the regressive motor burns, thrust decreases as the burning surface area of the propellant decreases — typical of slotted grains.

  20. #20Which describes the thrust curve of a progressive motor?

    Motor Characteristics
    1. A)A general decrease in thrust during the burn
    2. B)A general increase in thrust during the burnCorrect
    3. C)About the same thrust at ignition as at burnout

    Why: As a progressive motor burns, thrust increases because the burning surface area increases. Typical of core-burning motors.

  21. #21A Bates grain has an essentially neutral thrust curve because:

    Motor Characteristics
    1. A)Core burning motors always have a neutral thrust curve
    2. B)The area of burning propellant remains relatively constantCorrect
    3. C)The core is centered in the propellant grain

    Why: As the motor burns from the core out, the ends also burn, making the grains shorter. This keeps the surface area relatively constant for a flat / neutral thrust curve.

  22. #22What is the most common function of a motor liner and the O-ring seals in a solid rocket motor?

    Motor Internals
    1. A)To hold all the parts in place prior to ignition of the rocket motor
    2. B)To make the motor easier to clean if it is a reloadable motor
    3. C)To keep the hot gasses of the motor from burning or melting the motor caseCorrect

    Why: The liner keeps burning propellant from touching the motor case (aluminum melts at 1075°F) while the O-rings seal the ends to keep hot gasses going out of the nozzle.

  23. #23What is the most common oxidizer in commercially available high power composite solid rocket motors?

    Propellant Chemistry
    1. A)Ammonium PerchlorateCorrect
    2. B)Ammonium Nitrate
    3. C)Ammonium Chlorate

    Why: Ammonium Perchlorate is NH4ClO4 and is used in practically all modern solid rocket motors.

  24. #24What is NH4ClO4?

    Propellant Chemistry
    1. A)Ammonium PerchlorateCorrect
    2. B)Ammonium Nitrate
    3. C)Ammonium Chlorate

    Why: NH4ClO4 is the chemical formula for Ammonium Perchlorate.

  25. #25A small hole is typically drilled near the top of a high-power rocket's airframe, below the nosecone or payload section. Why?

    Airframe Construction
    1. A)This hole vents excessive ejection charge pressure, reducing shock cord stress
    2. B)The hole permits on-board altimeters to obtain air pressure readings
    3. C)The hole vents internal air pressure as the rocket gains altitude to prevent premature separationCorrect

    Why: Air pressure external to the rocket decreases as it ascends. Trapped (higher) pressure within can prematurely separate the rocket. The hole vents this internal pressure.

  26. #26How do you convert Newtons of thrust to pounds of thrust?

    Units & Conversions
    1. A)Add 4.45 to the number of Newtons
    2. B)Multiply Newtons by 4.45
    3. C)Divide Newtons by 4.45Correct

    Why: Divide by 4.45.

  27. #27What is a Newton?

    Units & Conversions
    1. A)1 kg*m/s
    2. B)1 kg*m/s^2Correct
    3. C)1 kg*m

    Why: kg*m/s^2.

  28. #28What is the oxidizer most commonly used in a commercial hybrid rocket motor?

    Hybrid Motors
    1. A)N2OCorrect
    2. B)N2O4
    3. C)NO2

    Why: N2O — nitrous oxide, also called NOX.

  29. #29For a rocket with a much less than 10:1 "length to diameter" (L/D) ratio, such as spools and pyramids, what type of drag contributes significantly to stability and makes it possible to fly without much, if any, nose weight?

    Drag
    1. A)Nose drag
    2. B)Base dragCorrect
    3. C)Surface drag

    Why: Base drag. Bruce Levison explained how base drag effectively shifts the dynamic CP rearward for short wide rockets, allowing such designs to fly without adding nose weight.

  30. #30When doing an air-start of an L class motor, which of the following would be considered the safest configuration?

    Air-Start & Cluster
    1. A)A single computer driving a single initiatorCorrect
    2. B)Two computers each driving one initiator with a 0.5 second delay between firing the two initiators
    3. C)Two computers each driving one initiator with no delay between them

    Why: A single computer driving a single initiator is the safest configuration.

  31. #31A rocket with a motor cluster consisting of a central composite motor and four black powder motors, using five identical igniters:

    Air-Start & Cluster
    1. A)Will result in all motors starting about the same time
    2. B)Will result in the composite motor starting first followed by the black powder motors
    3. C)Will result in the black powder motors starting first followed by the central composite motorCorrect

    Why: Black powder motors ignite as soon as the flame front is encountered. AP composite motors require heat and pressure and typically need at least a half-second before ignition.

  32. #32What typically happens to a marginally stable rocket with a hybrid motor during the thrusting phase?

    Hybrid Motors
    1. A)Nothing
    2. B)The rocket may become more stable
    3. C)The rocket may become less stableCorrect

    Why: As the CG of the hybrid motor shifts aft, so does the CG of the rocket, which may result in an unstable flight.

  33. #33In general terms, the specific impulse of a rocket motor is:

    Impulse & Motor Class
    1. A)The total thrust force of a motor throughout its action time
    2. B)The total impulse divided by a unit weight of propellantCorrect
    3. C)Inversely related to the diameter and length of the propellant grain

    Why: Specific impulse is a measure of propellant efficiency — total impulse divided by unit weight of propellant.

  34. #34In general terms, the total impulse of a rocket motor can be described as:

    Impulse & Motor Class
    1. A)The product of the average motor thrust and burn timeCorrect
    2. B)The product of the propellant weight and burn time
    3. C)The product of the propellant weight and the motor thrust

    Why: Total impulse is the amount of thrust a motor produces over its action time. E.g., 10 lbs of thrust for 4 seconds = 40 lb-seconds.

  35. #35The average thrust of a rocket motor is 100 Newtons, and the burn time is 4 seconds. What is the total impulse?

    Impulse & Motor Class
    1. A)25 Newton-seconds
    2. B)400 Newton-secondsCorrect
    3. C)400 Newtons

    Why: Multiply average thrust (100 N) by burn time (4 s) for 400 N-s.

  36. #36Which of the motors listed below has the highest total impulse?

    Impulse & Motor Class
    1. A)J200
    2. B)J400
    3. C)K200Correct

    Why: J motors range 641–1280 N-s; K motors range 1281–2560 N-s. The K200 has the highest total impulse.

  37. #37Which of the motors listed below has the highest average thrust?

    Impulse & Motor Class
    1. A)J200
    2. B)J400Correct
    3. C)K200

    Why: Even though the K200 has more total impulse, the J400's average thrust (400 N) exceeds the K200's (200 N).

  38. #38What is the difference between a J640 and a J320 high power rocket motor (assume full 1280 Newton-second J motors)?

    Impulse & Motor Class
    1. A)There is no difference between the motors, the numbers are manufacturer reference only
    2. B)The J320 burns out twice as fast as the J640
    3. C)The J640 burns out twice as fast as the J320Correct

    Why: Burn time = total impulse / average thrust. J640: 1280/640 = 2 s. J320: 1280/320 = 4 s. The J640 burns twice as fast.

  39. #39Which of the following has a total impulse (It) in the J motor range?

    Impulse & Motor Class
    1. A)It = 600 Newton-seconds
    2. B)It = 1000 Newton-secondsCorrect
    3. C)It = 1290 Newton-seconds

    Why: A J motor is in the range of 640.01 to 1280 N-s. 1000 N-s is a midrange J. 600 N-s is an I motor; 1290 N-s is a K motor.

  40. #40What is a Newton?

    Units & Conversions
    1. A)The amount of force required to accelerate one pound one foot per second per second
    2. B)The amount of force required to accelerate one kg one foot per second per second
    3. C)The amount of force required to accelerate one kg one meter per second per secondCorrect

    Why: The Newton is the metric unit of force — the force required to accelerate one kilogram (2.2 lbs) one meter (39.4 inches) per second per second.

  41. #41What does the motor designation I220-8 mean?

    Impulse & Motor Class
    1. A)The motor has between 320-640 N-s of impulse, an average thrust of 220 Newtons, with approximately 8 seconds between motor ignition and ejection
    2. B)The motor has 220 N-s of impulse, an average thrust of 220 Newtons, with 8 seconds between motor burn-out and ejection
    3. C)The motor has between 320-640 N-s of impulse, an average thrust of 220 Newtons, with approximately 8 seconds between motor burn-out and ejectionCorrect

    Why: An I motor has a total impulse range of 320.01 to 640 N-s. The 220 is average thrust in N, and the -8 is the ejection delay in seconds after burnout.

  42. #42Rocket A is descending at 10 feet per second, rocket B weighs the same but is descending at 20 feet per second. Which statement is true?

    Energy & Kinematics
    1. A)The two rockets have the same kinetic energy
    2. B)Rocket B has two times the kinetic energy of rocket A
    3. C)Rocket B has four times the kinetic energy of rocket ACorrect

    Why: KE = ½mv². Velocity is squared, so doubling velocity (with the same mass) gives four times the kinetic energy.

  43. #43Rocket A weighs twice as much as rocket B. Both are descending at 20 feet per second. Which statement is true?

    Energy & Kinematics
    1. A)The two rockets have the same kinetic energy
    2. B)Rocket A has two times the kinetic energy of rocket BCorrect
    3. C)Rocket A has four times the kinetic energy of rocket B

    Why: KE = ½mv². Kinetic energy is directly proportional to mass — doubling the mass doubles the KE.

  44. #44What is the purpose of a launch rod, rail or tower?

    Launch System
    1. A)To keep the rocket pointing in the right direction prior to flight
    2. B)To control the rocket's flight long enough to allow aerodynamic stability
    3. C)Both a. and b.Correct

    Why: The launch rod/rail/tower governs the rocket's initial trajectory and guides it long enough to gain sufficient velocity for stable flight.

  45. #45What is the purpose of a launch lug or rail buttons?

    Launch System
    1. A)To add drag to the rocket at launch
    2. B)To guide the rocket along the launch rod or railCorrect
    3. C)Both a. and b.

    Why: Launch lugs / rail buttons attach the rocket to the launch rod or rail so it can be guided at launch.

  46. #46For a cluster rocket, which construction technique will minimize the effect of one motor failing to ignite?

    Air-Start & Cluster
    1. A)Make the holes in the forward centering ring slightly closer to the rocket's centerline than those of the aft centering ringCorrect
    2. B)Space the centering rings precisely one motor length apart
    3. C)Use four smaller fins instead of three larger fins

    Why: If the axis of the motor passes through or very near the center of gravity, the effect of unbalanced thrust is reduced. Bringing the forward ends of motors closer to the rocket axis helps.

  47. #47What can happen if all the motors of a cluster do not ignite at launch?

    Air-Start & Cluster
    1. A)Nothing, if the rocket is inherently stable
    2. B)The rocket may not fly straightCorrect
    3. C)The rocket will shred

    Why: Not having ignition of all clustered motors results in asymmetric thrust, which may force the rocket into an arc that will not achieve vertical flight.

  48. #48What is a shred?

    Failure Modes
    1. A)A failure of the rocket air frame during boost resulting in destruction of the rocketCorrect
    2. B)A failure of the recovery system during boost
    3. C)A failure of the motor causing early ejection

    Why: A shred occurs when a rocket is improperly built or the motor is too powerful for the rocket, causing the airframe, fins, or other structural parts to fail under load.

  49. #49What is a Cato?

    Failure Modes
    1. A)A failure of the rocket resulting in failure of the air frame during boost
    2. B)A failure of the recovery system during boost
    3. C)A failure of the motor causing flight terminationCorrect

    Why: A Cato is short for catastrophic motor failure. It occurs when the nozzle, forward bulkhead, or casing fails. The thrust is abruptly terminated and the rocket fails.

  50. #50What is the primary requirement for a rocket motor ignitor?

    Ignition
    1. A)It must transfer sufficient heat to the propellant to assure ignitionCorrect
    2. B)It must produce hot, high velocity gasses to assure ignition
    3. C)It must have a high resistance to be reliable

    Why: A motor igniter must deliver sufficient heat to the propellant to ignite it. This may be in the form of hot gas, hot burning particles, a hot wire, or a combination.

  51. #51Most APCP (ammonium perchlorate composite propellant) rocket motors are central-burning rather than end-burning:

    Motor Internals
    1. A)Because most APCP has a specific impulse that is too low for end-burning motors
    2. B)Because most APCP has a burn rate that is too low for useful end-burnersCorrect
    3. C)The premise is incorrect; most APCP motors ARE end-burners

    Why: APCP has about three times the specific impulse of black powder but burns slowly. It needs a large burning surface area, like a Bates grain or core-burning config, to generate enough hot gas for flight.

  52. #52Which of the following is most likely in dual-deployment rockets that use a drogue and a main parachute?

    Recovery & Altimeters
    1. A)The drogue and the main can tangle if not properly arrangedCorrect
    2. B)The drogue slows the rocket too much and it drifts too far
    3. C)The drogue does not slow the rocket enough and it lands hard

    Why: The drogue and main usually must be arranged to eject from separate sections to minimize tangling. In some cases a drogue isn't used at all to avoid the problem.

  53. #53When using an accelerometer-based altimeter in a rocket that may exceed Mach 1:

    Recovery & Altimeters
    1. A)A "Mach delay" must be built into the altimeter to avoid deployment of the recovery system at Mach
    2. B)One or more access holes must be drilled in the electronics bay to permit access to the atmosphere during flight
    3. C)Neither a. nor b. need be doneCorrect

    Why: Accelerometers measure acceleration entirely within the chip. Access to the atmosphere isn't required, and air pressure changes at Mach 1 don't affect the accelerometer chip.

  54. #54When using a pressure-sensor altimeter in a rocket that will not reach Mach 1:

    Recovery & Altimeters
    1. A)One or more access holes must be drilled at the base of the nose cone to permit access to the atmosphere during flight
    2. B)A timer, but not a motor delay, may be used as backup for deployment
    3. C)One or more holes must be drilled in the electronics bay for atmospheric accessCorrect

    Why: A pressure-sensor altimeter requires access to the atmosphere, so the electronics bay must be vented.

  55. #55What is the major issue with accelerometer-based altimeters?

    Recovery & Altimeters
    1. A)They are larger, and usually much more expensive, than pressure-sensor altimeters.
    2. B)They do not have multiple capabilities such as dual deployment, ignition of air-starts, etc.
    3. C)They may not deploy properly if the flight is significantly off-verticalCorrect

    Why: Accelerometers can be small, inexpensive, and capable. But the electronics assume a near-vertical flight, so significant deviation from vertical may cause problems.

  56. #56What is the purpose of the Tripoli Unified Safety Code?

    Safety Code Purpose
    1. A)Establish guidelines for reasonably safe operation of rockets at a Tripoli launchCorrect
    2. B)Establish guidelines for building of rockets at a Tripoli launch
    3. C)Establish guidelines for the building of motors at a Tripoli launch

    Why: The Tripoli Unified Safety Code (TUSC) establishes guidelines for the reasonably safe operation of rockets at a Tripoli launch.

    Reference: TUSC 1-2.1

  57. #57Although Tripoli launches involve several layers of safety rules intended to increase safety, _____ is ultimately responsible for the rocket and flight?

    Responsibility & Authorities
    1. A)The Range safety officer
    2. B)The launch Director
    3. C)The flierCorrect

    Why: The flier is ultimately responsible for the rocket and the flight.

    Reference: TUSC 7-1

  58. #58The flier shall document the location of the center of ____ and be able to demonstrate the center of _____ ? (Answer in order of blanks)

    Stability Documentation
    1. A)Gravity, Pressure
    2. B)Pressure, GravityCorrect
    3. C)Pressure, Thrust

    Why: Document the center of pressure; demonstrate the center of gravity.

    Reference: TUSC 7-1.2

  59. #59Which of the following motor types are not allowed to be made and flown by a Level 2 flier as a research motor?

    Research Motors
    1. A)Research Black Powder Motor
    2. B)Liquid rocket motors (except nitrous oxide hybrids)
    3. C)Both a. and b.Correct

    Why: Neither research black powder motors nor liquid rocket motors (except N2O hybrids) may be made and flown by an L2 as research motors.

    Reference: TUSC 10-8

  60. #60Rockets flown at Tripoli launches may carry:

    Payloads
    1. A)Vertebrate Animals
    2. B)Hazardous payloads including those which are poisonous, flammable, incendiary, or explosive
    3. C)Neither a. nor b.Correct

    Why: Neither vertebrate animals nor hazardous payloads.

    Reference: TUSC 7-9

  61. #61What is the Authority Having Jurisdiction (AHJ)?

    Definitions
    1. A)The organization, office or individual responsible for enforcing requirements of a code or standard, or for approving equipment, materials, an installation or a procedureCorrect
    2. B)A court proceeding that rule on high power rocketry activities
    3. C)The individual preparing a high-power rocket for flight

    Why: The AHJ is the organization, office, or individual responsible for enforcing requirements of a code or standard.

    Reference: TUSC 15 — Definition of AHJ

  62. #62What is a complex high-power rocket?

    Definitions
    1. A)A rocket having more than one stage
    2. B)A rocket having a cluster of rocket motors
    3. C)Either a. or b.Correct

    Why: A complex high-power rocket is either multi-stage or has a cluster of motors.

    Reference: TUSC 15 — Definition of Complex Rocket

  63. #63What are the minimum criteria that define a high-power rocket?

    Definitions
    1. A)A rocket with a single motor with more than 160 Newton-seconds total impulse or an installed impulse of 320 Newton-seconds and no more than 40,960 Newton-seconds
    2. B)A rocket with a single motor having an average thrust in excess of 80 Newtons or any sparky rocket motor (usually using titanium pieces)
    3. C)Either a. or b.Correct

    Why: Either condition defines a high-power rocket.

    Reference: TUSC 15 — Definition of High Power Rocket/Motor

  64. #64What is the maximum weight of a model rocket with motors installed?

    Definitions
    1. A)53 oz. (1500 g)Correct
    2. B)1 lb. (453.6 g)
    3. C)There is no maximum weight limit to a model rocket

    Why: 53 oz / 1500 g maximum with motors installed.

    Reference: TUSC 15 — Definition of Model Rocket

  65. #65When is an active recovery device not necessary in a high-power rocket?

    Recovery
    1. A)When the high-power rocket is intended for ballistic flight
    2. B)When the rocket has a bursting charge
    3. C)When the rocket employs a passive recovery system (e.g.: tumble recovery, aero-braking)Correct

    Why: An active recovery device isn't required when a passive recovery system is used.

    Reference: TUSC 11-2

  66. #66Range activity shall cease whenever a thunderstorm has been detected within ____ miles (kilometers) of the launch site?

    Weather
    1. A)5 (8 kilometers)
    2. B)10 (16 kilometers)Correct
    3. C)20 (32 kilometers)

    Why: 10 miles / 16 km.

    Reference: TUSC 7-10

  67. #67At what total impulse and/or average thrust does a motor become high power?

    Definitions
    1. A)A rocket motor with more than 80 Newton-seconds of total impulse and 80 Newtons average thrust
    2. B)A rocket motor with more than 160 Newton-seconds of total impulse or 80 Newtons average thrustCorrect
    3. C)A rocket motor with more than 160 Newton-seconds of total impulse and 160 Newtons average thrust

    Why: More than 160 N-s total impulse OR 80 N average thrust.

    Reference: TUSC 15 — Definition of High-Power Rocket Motor

  68. #68While a 3:1 average thrust to weight ratio is the absolute minimum established in the Tripoli Unified Safety Code, what is the typical initial minimum thrust to weight ratio for a rocket?

    Stability Documentation
    1. A)4:1
    2. B)5:1Correct
    3. C)12:1

    Why: 5:1 is the typical initial minimum thrust-to-weight ratio.

    Reference: TUSC 7-1.4

  69. #69Who may operate a high-power rocket?

    Responsibility & Authorities
    1. A)Any member of a nationally recognized rocketry organization
    2. B)Only those licensed by the federal government
    3. C)A certified user as defined in the Tripoli Unified Safety CodeCorrect

    Why: A certified user as defined in the TUSC.

    Reference: TUSC 15 — Definition of High-Power Rocket Flier (HPR Flier)

  70. #70What operating clearances must be complied with for flying high power rockets?

    Regulations
    1. A)The Tripoli Unified Safety Code
    2. B)The Tripoli Unified Safety Code, Regulations controlling airspace for country of launch and any other applicable federal, state and local regulationsCorrect
    3. C)NFPA and the FAA

    Why: TUSC plus airspace regulations and any other applicable federal, state, and local regulations.

    Reference: TUSC 3-1 (1.1, 1.2, 1.3)

  71. #71What criteria apply to the construction of a high-power rocket?

    Construction
    1. A)Use suitable materials to withstand operating stresses and retain structural integrity in flightCorrect
    2. B)Use only the lightest weight materials for the construction of high-power rockets
    3. C)Use materials that allow minimal flex of the rocket in flight

    Why: Materials must withstand operating stresses and retain structural integrity.

    Reference: TUSC 7-1.1

  72. #72When must the stability of a rocket be determined?

    Stability Documentation
    1. A)If the safety monitor requests it
    2. B)During the design of the rocket
    3. C)When the rocket is prepared for flightCorrect

    Why: Stability must be determined when the rocket is prepared for flight.

    Reference: TUSC 7-1.2

  73. #73Who can override an RSO decision pertaining to safety?

    Responsibility & Authorities
    1. A)RSO decisions pertaining to safety are final and may not be overridden by any other range personnel including the launch directorCorrect
    2. B)The Launch Director
    3. C)A Tripoli BOD member, prefect, or TAP

    Why: RSO safety decisions are final.

    Reference: TUSC 8-3

  74. #74When is it permissible to catch a high-power rocket?

    Recovery
    1. A)If the rocket weighs less than 2.2 pounds or 1 kg
    2. B)It is never permissible to catch a high-power rocketCorrect
    3. C)If the rocket is falling slowly enough that it is deemed not to be a hazard

    Why: It is never permissible to catch a high-power rocket.

    Reference: TUSC 11-5

  75. #75Except for pertaining to safety, who may override a launch directors' decision?

    Responsibility & Authorities
    1. A)The LCO
    2. B)A Tripoli BOD member, prefect or TAP
    3. C)Except for pertaining to safety, the launch director's decision is final and cannot be overriddenCorrect

    Why: Outside of safety, the LD's decision is final.

    Reference: TUSC 8-4

  76. #76When must a high power rocket launching device incorporate a blast deflector?

    Launch Equipment
    1. A)When necessary to prevent damage or reduce risk of fireCorrect
    2. B)All launch systems must incorporate a blast deflector
    3. C)When the design of the launch device requires it

    Why: When necessary to prevent damage or reduce risk of fire.

    Reference: TUSC 7-5

  77. #77What is the maximum launch angle from vertical for a high-power rocket?

    Launch Conditions
    1. A)30°
    2. B)20°Correct
    3. C)There is no maximum launch angle

    Why: 20° maximum.

    Reference: TUSC 13-6

  78. #78What are the elements of an ignition system?

    Ignition
    1. A)Wireless controlled, electrically operated, a launch switch that returns to OFF when released
    2. B)Wireless controlled, electrically operated and a removable safety interlock in series with the launch switch
    3. C)Includes an arming switch with a removable key or interlock, which disables the entire launch control system when removed and uses a momentary switch to command the rocket motor ignitionCorrect

    Why: Arming switch with removable key/interlock plus momentary firing switch.

    Reference: TUSC 7-7.1, 7-7.2

  79. #79When shall the motor ignitor(s) be installed in a high-power rocket motor?

    Ignition
    1. A)At the launcher or a designated prep areaCorrect
    2. B)When the motor is installed in the rocket
    3. C)Neither a. nor b.

    Why: At the launcher or a designated prep area.

    Reference: TUSC 13-7

  80. #80When may the physical disconnects that inhibit energetics be connected to power?

    Ignition
    1. A)In the flier Prep area
    2. B)At the pad or other designated range area as indicated by the launch directorCorrect
    3. C)Both a. and b.

    Why: At the pad or other designated range area indicated by the launch director.

    Reference: TUSC 13-8

  81. #81What is a class 1 rocket?

    Definitions
    1. A)A model rocket with a G motor or smaller
    2. B)A model rocket with more than 125 g (4.4 oz.) of propellant and more than 1500 g (53 oz.) pad weight
    3. C)A model rocket with 125 g (4.4 oz.) or less of propellant and 1500 g (53 oz.) or less pad weightCorrect

    Why: Class 1 = model rocket: ≤125 g of propellant and ≤1500 g pad weight.

    Reference: TUSC 15 — Definition of Model Rocket

  82. #82What is the launch site criteria?

    Launch Site
    1. A)No less than one-quarter the maximum altitude expected or granted by the FAA
    2. B)No less than 1500 feet (457 m)
    3. C)Both a. and b.Correct

    Why: Both: at least 1/4 the max expected altitude AND at least 1500 ft.

    Reference: TUSC 13-16.1

  83. #83What is the minimum distance from a launch site to any person or property not associated with the operation?

    Safe Distances
    1. A)1000 feet (305 m)
    2. B)1500 feet (457 m)Correct
    3. C)No minimum distance if the building occupants are informed of the activity.

    Why: 1500 ft (457 m).

    Reference: TUSC 13-16.1

  84. #84How close can spectators be to a high-power rocket launch?

    Safe Distances
    1. A)At the distance defined by the Safe Distances TableCorrect
    2. B)Half the distance defined in the Safe Distance Table
    3. C)Double the distance defined in the Safe Distance Table

    Why: At the distance defined by the Safe Distance Table.

    Reference: TUSC 13-17 Safe Distance Table

  85. #85What is the maximum altitude allowed for flying high power rockets if there is a cloud ceiling of 3,000 feet (914 m) and an FAA waiver to 15,000 feet (4572 m)?

    Weather
    1. A)Up to 15,000 feet (4572 m)
    2. B)Up to 3,500 feet (1067 m)
    3. C)Up to 3,000 feet (914 m)Correct

    Why: Up to the cloud ceiling: 3,000 ft.

    Reference: TUSC 9-6

  86. #86What is the limit of surface wind for launching a high-power rocket?

    Weather
    1. A)30 MPH (48 km/h)
    2. B)20 MPH (32 km/h)Correct
    3. C)15 MPH (24 km/h)

    Why: 20 MPH / 32 km/h.

    Reference: TUSC 9-3

  87. #87When may a high-power rocket be launched?

    Launch Procedures
    1. A)After warning the spectators and after giving a 5 second countdown
    2. B)When all systems are ready and after giving a 5 second countdown
    3. C)After announcing the rocket and after giving a 5 second countdownCorrect

    Why: After announcing the rocket and giving a 5-second countdown.

    Reference: TUSC 9-1, 9-2

  88. #88What is a class 2 rocket?

    Definitions
    1. A)A rocket other than a model rocket propelled by motors with greater than a combined total impulse of 640 N-s (143.9 lb-s)
    2. B)A rocket other than a model rocket propelled by motors with greater than a combined total impulse of 40960 N-s (9208 lb-s)
    3. C)A rocket other than a model rocket propelled by motors with less than a combined total impulse of 40960 N-s (9208 lb-s)Correct

    Why: Class 2 = not a model rocket and propelled by motors with combined total impulse less than 40,960 N-s.

    Reference: TUSC 15 — Definition of High Power Rocket

  89. #89What is the minimum distance for smoking (or open flames) from high power rocket motors, motor reloading kits and pyrotechnic modules?

    Safe Distances
    1. A)10 feet (3m)
    2. B)25 feet (8m)Correct
    3. C)There is no minimum distance

    Why: 25 feet / 8 m.

    Reference: TUSC 13-14.1

  90. #90When are you allowed to install an igniter or head end ignition module into any motor including a multistage, cluster or air start type rocket?

    Ignition
    1. A)In the flier prep area
    2. B)At the RSO table
    3. C)At the pad or other designated area as established by the launch directorCorrect

    Why: At the pad or designated area as established by the LD.

    Reference: TUSC 13-7

  91. #91An R/C Rocket Boosted Glider (RBG) may be launched in which direction in regard to the flightline?

    Special Vehicles
    1. A)Parallel to or away fromCorrect
    2. B)Parallel to or towards
    3. C)There is no direction requirement

    Why: Parallel to or away from the flightline.

    Reference: TUSC 14-3.8

  92. #92At what impulse does a class 3 rocket start?

    Definitions
    1. A)Above 5120 N-s (1151 lb-s)
    2. B)Below 40960 N-s (9208 lb-s)
    3. C)Above 40960 N-s (9208 lb-s)Correct

    Why: Class 3 = above 40,960 N-s.

    Reference: TUSC 15 — Definition of Class 3 Rocket

  93. #93Test flights or first flights of R/C RBG shall be launched from the distance specified by the total installed impulse in the Safe Distance Table plus _____ Ft?

    Special Vehicles
    1. A)0
    2. B)50
    3. C)100Correct

    Why: Plus 100 ft.

    Reference: TUSC 14-3.3

  94. #94What is the maximum angle (in degrees) from vertical a model rocket can be launched from?

    Model Rockets
    1. A)30Correct
    2. B)20
    3. C)10

    Why: 30° from vertical for model rockets.

    Reference: TUSC 12-1

  95. #95The minimum safe distance to any spectator when a model rocket is launched shall be _____ Ft?

    Model Rockets
    1. A)30
    2. B)50Correct
    3. C)100

    Why: 50 ft minimum.

    Reference: TUSC 12-4

  96. #96The minimum distance for all involved rockets shall be the complex distance for the total installed impulse of the motors in all rockets when _____ or more rockets are launched simultaneously?

    Safe Distances
    1. A)1
    2. B)2
    3. C)3Correct

    Why: 3 or more rockets launched simultaneously.

    Reference: TUSC 13-13.1

  97. #97When can steel nozzles be used in research motors?

    Research Motors
    1. A)When the nozzle throat is recessed within the case of a sugar motorCorrect
    2. B)On any research motor
    3. C)Never

    Why: When the nozzle throat is recessed within the case of a sugar motor.

    Reference: TUSC 10-10.5

  98. #98What is the age limit Tripoli recognizes for a certified solid propellant high power rocket motor user?

    Definitions
    1. A)21 years of age
    2. B)18 years of ageCorrect
    3. C)There is no age limit

    Why: 18 years of age.

    Reference: TUSC 15 — Definition of Adult flier, High Power Rocket Flier

  99. #99What is the minimum safe distance for a non-complex H, I or J motor?

    Safe Distances
    1. A)50 ft (15m)
    2. B)100 ft (30m)Correct
    3. C)200 ft (61m)

    Why: 100 ft / 30 m.

    Reference: TUSC 13-17 Safe Distance Table

  100. #100When may Research Motors that have been sold for a profit be used at a Tripoli Launch?

    Research Motors
    1. A)When the motors are not transported outside the state of manufacture
    2. B)When the sale of motors is limited to certified users
    3. C)It is never permittedCorrect

    Why: Never.

    Reference: TUSC 10-6

  101. #101Which of the following materials can be used for research motor cases?

    Research Motors
    1. A)Metallic cases made of non-ferrous ductile metals such as 6061 aluminum alloyCorrect
    2. B)Metallic cases made of ferrous metals such as Steel
    3. C)Non-metallic cases made of PVC

    Why: Non-ferrous ductile metals like 6061 aluminum.

    Reference: TUSC 10-10

  102. #102When is it permissible to consume alcohol when prepping or launching high power rockets?

    Personal Conduct
    1. A)When the preparation is done the day before the launch
    2. B)If the blood alcohol level is below the "impaired" level
    3. C)It is never permittedCorrect

    Why: Never.

    Reference: TUSC 7-12

  103. #103Organizations that may certify high power rocket motors include:

    Certifying Bodies
    1. A)Tripoli Rocketry Association (TRA) and the National Association of Rocketry (NAR) only
    2. B)The Bureau of Alcohol, Tobacco, Firearms, and Explosives (BATFE)
    3. C)TRA, NAR, and the Canadian Association of Rocketry (CAR)Correct

    Why: NAR S&T, CAR MCC, and Tripoli TMT reciprocally recognize each other.

    Reference: TUSC 15 — Definition of Certified Motor

  104. #104When can electronics that control energetics be powered on?

    Ignition
    1. A)Before closing the rocket ebay in your campsite
    2. B)After you have been through the rocket inspection
    3. C)After the rocket is vertical on the pad but before the motor igniter is installedCorrect

    Why: After the rocket is vertical on the pad but before the motor igniter is installed.

    Reference: TUSC 7-8, 13-8, 13-9

  105. #105The maximum landing speed of a rocket is not to exceed ____?

    Recovery
    1. A)50 ft/s (15 m/s)
    2. B)35 ft/s (11 m/s)Correct
    3. C)15 ft/s (4 m/s)

    Why: 35 ft/s (11 m/s).

    Reference: TUSC 11-1

  106. #106Who in Tripoli may certify a member Level 1 or Level 2?

    Certification
    1. A)The prefect
    2. B)A TAP member
    3. C)A member of the Tripoli Board of Directors, the prefect, or a TAP memberCorrect

    Why: BOD, prefect, or TAP member.

    Reference: Tripoli certification procedures (tripoli.org/certification)

  107. #107Who is allowed in the high-power launch area at a Tripoli launch?

    Launch Area
    1. A)Any invited person
    2. B)Spectators
    3. C)Tripoli TMP or Jr L1 NAR Members and any Tripoli or NAR member 18 years old or olderCorrect

    Why: Tripoli TMP / Jr L1 NAR Members and any Tripoli or NAR member 18+.

    Reference: TUSC 6-All

  108. #108When is electronically actuated recovery necessary?

    Recovery
    1. A)There is no requirement, it is up to the flier
    2. B)A high-powered rocket launched with an installed impulse greater than 2560 N-secCorrect
    3. C)A high-powered rocket launched with an installed impulse greater than 5120 N-sec

    Why: Required for installed impulse greater than 2560 N-s.

    Reference: TUSC 11-6