Information Pack for Mid Power Rockets · 2013. 10. 16. · Ejection The act of separating the...

Information Pack for Mid Power Rockets www.qldrocketry.com

QINFO-002 Mid Power Info Pack (Ver 1.2) 14 June 2013 of 23

Table of Contents

1. Introduction .................................................................................................................................... 2

2. Terminology .................................................................................................................................... 3

3. Rocket Flight Phases ....................................................................................................................... 4

4. Igniters ............................................................................................................................................ 5

5. Motors ............................................................................................................................................. 6

5.1 Key Components .......................................................................................................................... 6

5.2 Impulse ......................................................................................................................................... 7

5.3 Motor Identification ..................................................................................................................... 8

5.4 Single Use and Reloadable Motors .............................................................................................. 8

6. Deployment................................................................................................................................... 13

6.1 Delay Element ............................................................................................................................ 13

6.2 Electronic Deployment ............................................................................................................... 13

6.3 Deployment Methods ................................................................................................................ 14

7. Recovery Systems ......................................................................................................................... 16

8. Rocket Design Considerations .......................................................................................................... 17

8.1 Rocket Stability ........................................................................................................................... 17

8.2 Pressure Relief Holes .................................................................................................................. 17

9. Flight Records and other Data ...................................................................................................... 18

10. TRA Certification ....................................................................................................................... 19

11. Helpful Websites and Resources ................................................................................................... 21

Appendix A – Typical Reloadable Motor System .................................................................................. 22

Appendix B – Typical Motor Designation .............................................................................................. 23


1. Introduction

This information pack is to help rocketeers who are wishing to progress from low power rockets into the mid power range and beyond. It contains detailed information about the advanced aspects of rocketry including the construction, launch reparation and launching of rockets in this power range. Whilst the construction and preparation for flight can be a detailed and lengthy process, the actual launch and recovery of the rocket are over very quickly. The success of the flight is dependent on all of the preparatory phases being completed successfully. Rockets can be designed and built from scratch, or made from commercial kits. Design software programs are available to aid with the design of rockets. This design process results in the determination of the fin and nose cone shape, location of the on-board components (e.g. A/V bays) and will ultimately determine the centre of gravity and centre of pressure (These will determine if the rocket’s flight will be stable or not). Flights can also be simulated to determine the rocket’s performance for various motors and weather conditions. A great deal of time, effort and attention-to-detail will be required to ensure that your rocket is constructed to withstand the rigours of the more arduous flights associated with mid and high-powered rockets. Adhesives, fin orientation, parachute selection, electronic components will all be important considerations. The launch preparation will also require greater scrutiny. With the more elaborate high power rockets, some rocketeers will prepare a checklist for use during preparation to ensure that nothing is overlooked. The contents of this information pack will assist with some of these considerations.


2. Terminology

Term Description

Airframe The main section of the rocket. It contains the motor, parachute, A/V bay.

Apogee The point at which, after launching the rocket, the flight path changes from ascending to descending i.e. the highest point of ascent.

Avionics Bay (A/V) The section of the rocket that contains the electronics e.g. altimeter, GPS (usually only for high powered rockets).

Centre of Gravity The point of a rocket at which the weight is evenly distributed i.e.balance point along the rocket’s length.

Centre of Pressure The point of a rocket at which the aerodynamic lift of the rocket is centred. It is determined by the shape and length of the rocket, the shape and size of the nose cone, the number, size and shape of the fins.

Drogue Smaller parachute typically deployed at apogee that will slow the rocket’s descent until the main parachute is deployed at a lower altitude. Used to reduce the amount of drift experienced by a high power rocket.

Ejection The act of separating the rocket components during flight, thus deploying the recovery system from the rocket body.

Fillets The glued part of the rocket that secures the rocket frame to the fins.

Impulse The change in momentum per unit mass of propellant of a propulsion system. Measured in Newton.seconds (N.s).

Launch lugs The devices fastened to the external frame of the rocket that hold the rocket in place on the launch rod prior to launching.

Launch rod The vertically mounted assembly that aims the rocket upwards before launch.

Launch Control Officer (LCO) The person at the launch site who has the responsibility and duty to:

Ensure that the ignition system is working correctly, and;

The rocket ignition leads are connected correctly, and;

Control the countdown, and;

Ensure the safety and continuity of rocket launches.

Motor A part of the rocket that provides propulsion.

Motor CATO A failure of the motor causing termination of the flight.

Natural Resources and Mines Queensland Government Department responsible for the issue of explosives licences in Queensland.

QRS Queensland Rocketry Society Inc. - the association responsible for the development of the hobby of rocketry in Queensland.

Range Safety Officer (RSO) The person at the launch site who has the responsibility and duty to:

ensure that any rocket presented for launch is fit for flight, and;

ensure that the TRA safety rules are being followed.

Recovery System The device that is deployed at the highest point of the launch that will then bring the rocket back to the ground at a controlled speed thus reducing the possibility of damage or injury.

Scratchbuilt A rocket can be designed and constructed by the owner using kit and non-kit components.

TRA Tripoli Rocketry Association Inc. - the international organisation responsible for organising the sport worldwide.

Wadding Insulated material inserted into the airframe between the recovery assembly and the ejection charge to prevent burning of the recovery assembly


3. Rocket Flight Phases The rocket flight has five distinct phases as shown in the table below.

Flight Phases Description

Ignition This stage involves applying a heat source to the rocket motor sufficient to cause the ignition of the motor propellant. Igniters are used for this purpose and consist of two wires

with a small amount of material that will burn when a high enough current is supplied. This confers heat to the motor sufficient to cause ignition.

Thrust (Powered flight)

At ignition, pressure builds rapidly inside the motor and superheated gases exit the exhaust nozzle. The rocket is propelled upward until all of the propellant in the motor is burnt. it accelerates to a velocity determined by the motor impulse, rocket weight and body tube cross-section area. Powered flight may last from as little as a fraction of a second to many

seconds for high power motors. The rocket reaches its maximum speed just before the end of the thrust phase.

Coast (Unpowered flight)

This is the phase during which the rocket momentum continues to carry rocket upwards until all speed is lost. This is the phase where the rocket is decelerating due to gravity and air

resistance and will eventually cease its upward motion. It can be much longer than the powered

segment. Most of the altitude is gained during this phase.

Deployment Ideally, deployment will occur at the instant the rocket has ceased its upward motion and has begun falling back toward the ground. The ejection charge pushes the rocket sections apart to enable the recovery system (parachute or streamer) to deploy. If packed correctly, the recovery system will open completely.

Descent Once the recovery system is deployed, the rocket begins a controlled descent. The downward motion is generally arrested by the deployment of a recovery device such as parachutes or streamers.

If the recovery system fails e.g. separates from the rocket or fails to open, it is almost certain that the rocket will be damaged when it impacts the ground. Uncontrolled descents pose a hazard to any persons in the vicinity.


4. Igniters

Igniters, as the name implies, are used to ignite the propellant. They consist of a thin wire element

secured across the two igniter wires with terminals. When a battery voltage is applied to the wire

terminals, the thin wire element heats up and commences the thermal reaction in the propellant.

The terminals are connected to the battery via the launch control box.

For low power rockets, the igniter can be installed into the rocket in the prep area. For high

powered motors, the igniter must be inserted into the rocket only after it has been positioned on

the launch pad and the AV bay components have been activated.

Three typical types of igniters available are listed in the table below.

Igniter Description Example

Copperhead Igniter has strips of a thin copper foil on either

side of an insulating medium. The two copper

strips act as the positive and negative leads for

the battery. An igniter head on the ignition

leads is completes the circuit. A special launch

lead assembly is required to connect the igniter

to the battery. These are used for G and below

motors.

First fire These have a similar ignition head but are

connected by traditional insulated copper wires.

There are two types: First Fire and First Fire

Junior. The First Fire is used for high power

motors. The First Fire Junior is used for ‘G’ and

below motors and should not be used for

deployment ejection charges.

e-match These are similar to the First Fire and are used

more commonly to ignite black powder ejection

charges for altimeter-initiated deployment.

They can also be used for the ignition of black

powder and some other motors.


5. Motors

Motors are the generic term for the component of the rocket that provides the propulsion (thrust).

A wide variety of motors can be inserted into the rocket prior to launching providing high speed or

high altitude launches.

They come in various sizes and shapes depending on the impulse range and manufacturer. Rockets

are designed to accommodate the desired motor’s physical size and impulse range.

There are two main motor types available in model rocketry; solid propellant and hybrid. Hybrid

motors typically use a liquid oxidiser (such as nitrous oxide) along with a solid fuel (typically a type of

plastic).

In this document we will only cover solid propellant motors.

5.1 Key Components

The key components of a propulsion system are as follows:

Component Description

Propellant This provides the thrust for the motor. This is the main part of the motor occupying

the greatest space. Propellant can be black powder or Ammonium Perchlorate

based.

Delay element This has three purposes –

It provides the time delay between when the propellant is exhausted and when the ejection charge is ignited. The delay can be adjusted in some motors by drilling out a small amount of the charge.

It burns producing a trail of white smoke in the sky as it coasts to apogee. This assists with tracking the progress of the rocket.

It also ignites the ejection charge. When the delay element combustible material has burnt through, there is enough heat to ignite the ejection charge.

Ejection charge This provides a small explosive charge that forces the nose cone to separate from the

airframe allowing the recovery system (parachute or streamer) to deploy. This

should occur at apogee.

For the low and medium powered power single-use and some reloadable motors, the three

components are combined into a single unit. For higher powered motors, separate components are

assembled to fill a more specific role e.g. ejection charges can be designed, prepared and installed in

purpose built sections of the rocket separate to the motor.


5.2 Impulse

Motors are categorised in impulse size (Newton seconds) using an alphabetical listing e.g. ‘A’ motors

are the most basic with the lowest impulse. The motor impulse then increases by factors of two

through the alphabet e.g. an ‘H’ motor has twice the impulse of a ‘G’ motor. At the time of writing,

the ‘O’ motor is the largest motor available for hobby purposes.

The larger hobby motors have certain restrictions in relation to their possession, storage and

transportation of motor propellant. In general terms, rocketeers must acquire a Queensland

Explosives licence to use motors with impulse ‘H’ and greater.

The table below shows the range of motors available and the rocketeer’s required certification level

to use them. (Source: USA National Association of Rocketry).

Note that the impulse limit listed is the maximum for the range e.g. an H motor can have an impulse

range between 160 – 320 N.secs even though it is listed as a fixed figure of 320 N.secs. Rocketeers

must check the manufacturer’s specifications to determine the actual impulse for a particular motor.

Hobby Rocket Motor Information

Classification Impulse Range Impulse Limit

(N.sec) Category

Model Rocket

1/4A 0.625

Low Power

1/2A 1.25

A 2.5

B 5

C 10

D 20

E 40

Mid Power F 80

G 160

High Power

H 320 Level 1

I 640

J 1280

Level 2 K 2560

L 5120

M 10240

Level 3 N 20480

O 40960


This can be used to determine the timing of the thrust phase and the maximum height that the

rocket can achieve.

5.3 Motor Identification

Rocket motors are identified with a three-part code that gives the rocketeer some basic

information about the motor's power and behaviour as follows:

A letter specifying the total impulse e.g. ‘C’;

A number specifying the average thrust in Newtons e.g. 6;

A number specifying the time delay between burnout and recovery ejection e.g. 3.

Hence a C6-3 motor is in the ’C’ impulse range, has an average thrust of six Newtons over the

motor burn time and a delay time to ejection of three seconds. With the larger motors,

there is an additional letter relating to the colour of the exhaust. Refer to Appendices

A and B.

5.4 Single Use and Reloadable Motors

Motors can be categorised as ‘single-use’ or ‘reloadable’. They also come in various sizes. The

appropriate sized motor must be selected to fit into the motor mount of the rocket.

Motor standard sizes for mid to high power rockets include 29mm, 34mm, 54mm, 78mm

and 98mm diameter.


Refer to the table below for details of typical motor types.

(Source: Aerotech Consumer Aerospace Catalogue).

Motor Description Typical Example

Single use It is used only once and is then discarded.

Comes in 1/4A, 1/2A and A – E sizes.

Reloadable The reloadable motor can be used many

times. The reloadable motor consists of a

metal cylinder (casing) with threaded

closures at both ends. Reload kits of various

impulses and thrusts can be used with the

reloadable motor. They come in a variety of

lengths and diameters to suit the rocket

construction and the desired performance.

Reload kits contain propellant, delay

elements, ejection charges, washers, O rings

and nozzles. They are assembled and then

installed into the rocket. After the launch,

the motor components are discarded but the

motor casing is kept for further use.

Single use motors contain propellant, delay elements and ejection charges. The casing consists of

multiple layers of tightly wound paper. It is wound into a cylindrical shape and the propellant, delay

element, nozzle and ejection charge are sealed inside by clay retainer caps. The assembly is easily

inserted into the motor mount and held in place by the retaining hook. It is important to ensure that

the motor is held in place inside the rocket. If not, it can be ejected when the ejection charge ignites

(the force of the ejection charge popping the nose cone can also propel the motor out the back of

the rocket if it is not constrained). For higher powered rockets, the motor is generally held in place

by screwed motor retaining assemblies.

The diagram below shows a typical single-use rocket motor assembly.


(Source: Phil Entwistle)

Reloadable motors can accommodate a variety of motor reload kits. The kits present a variety of

impulses, thrust and propellant types. The kits contain propellant, washers, ‘O’ rings, spacers,

nozzles, delay and ejection charges, igniters and instructions. The components of the kits are

assembled into the motor. The instructions must be followed completely. If any parts are installed

incorrectly or left out, then the motor may not perform correctly with catastrophic effect e.g. the

ejection charges may ignite early causing the parachute to deploy early, the motor casing may be

damaged and the rocket may experience motor cato.

Instructions are available with all kits. It is important that the rocketeer follow the instructions

precisely to ensure all components are incorporated and assembled in the correct order. If any

components are inserted incorrectly or omitted, the motor could fail.


Shown below is a typical reload kit. In this case, it is an Aertotech G64 -10 for a 29mm diameter,

120mm long motor.

(Source: Jeff Cheales)

Delay element

Delay Insulator

Instructions

Forward and

Aft O-rings

Ejection charge

Motor Casing

aft closure

Delay spacer

Motor Casing

forward closure

Forward insulator

Delay O-ring

Liner tubes containing

propellant grain

Copperhead igniter


The diagram below shows a typical mid power rocket motor assembly (in this case, the Aerotech kit

described above).

(Source: Phil Entwistle)

The kit is assembled by the rocketeer. Assembled kits cannot be transported with the igniter

inserted. This must be done at the launch pad.

The motor impulse can be increased with the number of propellant ‘grains’ that are incorporated.

These are billets of propellant that are inserted into the motor casing - the more grains, the greater

the impulse. The limitation for this is the dimension of the motor casing.


6. Deployment

In this phase, the recovery system deployment mechanism is triggered. A small charge is exploded

within the rocket ejecting the nose cone (or other parts of the rocket if dual-deployment is used). It

is accepted that the best approach is that the recovery system is deployed at or near apogee. This

ensures that the recovery system (parachute/streamer) and rocket structure will suffer little effects

from the upward or downward mechanical forces due to rocket momentum as it deploys.

There are two basic mechanisms that can initiate deployment: delay element and electronic.

6.1 Delay Element

A delay element is a small container of combustible material mounted on top of the motor

propellant within the motor. When the motor’s propellant has been exhausted, the delay element

ignites and slowly burns. Depending on the length and volume of the combustible material, it will

burn for a designated time (usually a few seconds) as specified in the manufacturer’s instructions

supplied with the reload kit. Ideally, it will burn for the duration of the coast period. When the

delay element has completely burned, it will ignite the ejection charge thus deploying the recovery

system.

With single use motors, the delay element is fixed in place and the delay timing cannot be altered.

However, with reloadable motors, the delay element timing can be changed by drilling out an

appropriate amount of the combustible material. Of course, this means that the time can only be

reduced, it cannot be extended. If the correct delay period has been chosen, the ejection charge

will be ignited and deployment will occur at, or near, apogee.

This is the cheapest and most popular means of deployment for low power rockets. It does,

however, have its disadvantages. This method is effective only if the correct delay time has been

calculated. If the ejection/deployment charge is ignited too early or too late, then the rocket may be

travelling at high speed (either on the up or downward phase of the flight. The recovery system will

be subjected to large forces and this may cause damage to the recovery system or rocket.

Simulation software can assist with determining the best delay timing. However, it is only an

approximation given the many variables that can affect these calculations e.g. coefficient of drag.

Trial and error with the various motors and delay charges will determine the correct delay element

timing for a particular rocket.

6.2 Electronic Deployment

The more sophisticated deployment technique is to utilise on-board electronic devices such as

altimeters. These devices have the advantage of:

Detecting apogee and deploying the recovery system at that time

Allowing for a second deployment at an altitude closer to the ground

Recording the rocket’s altitude for later performance evaluation

These devices are used in conjunction with separate black powder ejection charges. These charges

will be fired by the electronic device and will deploy the recovery systems. Electronic devices are


more expensive than the single-use delay element devices. However, they have the advantage of

virtually guaranteeing deployment at apogee. They will also record basic flight details for later

downloading and analysis.

Many mid to high power rockets will utilise motors that will launch to much higher altitudes. As

such, they will experience a greater drift when using normal parachutes. In these cases, dual-deploy

recovery systems are advised. A smaller parachute, called a drogue, will deploy at apogee. This will

create a controlled descent at a rate of about 8 – 10 meters / second. This allows the rocket to

descend at a faster, controlled rate that prevents excessive drift. When the rocket descends to a

pre-set altitude (determined by the on-board altimeter), the second, larger or ‘main’ parachute is

deployed. This will reduce the rate of descent to that required for a safe landing.

Some electronic devices will also have capability for tracking the rocket and location using GPS.

In many cases, rocket designers will allow for two on-board electronic devices with one as a back-up.

6.3 Deployment Methods

When the ejection charge ignites, it creates a large volume of heated gas within the rocket. This

generates a large force that is designed to separate the nose cone (or other body components) thus

allowing the deployment of the recovery system. The heated gas can cause damage to the recovery

system. Hence, it is important to shield the recovery system e.g. parachutes, streamers from the

heat.

We have already seen how the use of wadding and heat resistant material can be used as a buffer

between the ejection charge and the fragile parachutes/streamers for low power rockets.

For mid to high power rockets, the ejection charges are more substantial and can cause greater

damage.


For this level of rocketry, there are two basic deployment methods used - piston and straight

deployment with optional fire (blast) blanket.

Igniter Description Example

Piston The piston is a tight fitting in-line solid component of the recovery system It usually takes the shape of an open-ended cylinder made of phenolic, cardboard or similar material. It sits between the ejection charge and the deployment device inside the body of the rocket. The open end faces towards the ejection charge. The force of the ejection charge pushes the piston and the parachute out of the rocket and the recovery device is deployed. The piston protects the recovery device from heat damage from the hot gases. One end of the piston is connected to the motor mount. The other end is connected to the deployment device.

Fire blanket The fire blanket is made from a heat resistant material. It is attached to the shock cord of the deployment device. It is located between the ejection charge and the deployment device within the rocket. It is large enough that it can completely shield the deployment device from the hot gases of the ejection charge.


7. Recovery Systems

The recovery system is the combination of the electronics used for deploying the recovery device

and the recovery device itself.

The purpose of the recovery device is to provide a controlled descent of the rocket. This will reduce

the possibility of damage to the rocket or property. It will also contribute to the safety of personnel

on the ground. The recovery device may consist of streamers and/or parachutes. The ideal descent

rate for a rocket is about five metres/second.

Some recovery devices/methods are listed below.

Mode Description

Tumble Suitable only for small models. At deployment, the nose cone is ejected. This spoils the aerodynamic profile of the model causing a slower descent.

Streamer A streamer is used in place of a parachute. Suitable for smaller models.

Parachute The most popular mode of recovery. The size of the parachute is selected to provide a descent rate of approximately 15 feet/second (4.6 m/s) or less.

Dual Deploy

Uses two parachutes. A drogue ‘chute deployed at apogee allows a more rapid descent (25 – 30 feet/second) to reduce drift. The main ‘chute is deployed at a user defined height (around a few hundred feet). Only possible with a dual deploy capable altimeter and a suitably designed rocket.

The recovery device consists of a parachute/streamer, shock cord attachments and swivels.

Parachutes are available in various sizes. The selected size for a particular rocket will depend on the

weight of the rocket – the more the weight, the bigger the parachute.

The following table provides an indication of the variety of controlled descent devices available

(Source: Public Missiles Ltd)

Device Rocket Weight Parachute Size

Spill Hole Diameter Use

(oz) (kg) (inch) (mm) (inch) (mm)

Parachute 0 - 16 0 – 0.45 6 - 18 150 – 450 0 - 1 0 – 25 Main

Streamer 16 – 60 0.45 – 1.7 Drogue/Main

Parachute

16 – 120 0.45 – 3.4 18 450 4 100 Drogue

12 – 26 0.34 – 0.74 24 600 5 125

Main

24 – 34 0.68 – 0.96 30 30 5 125

30 – 42 0.85 – 1.20 36 36 8 205

36 – 54 1.0 – 1.5 48 48 8 205

50 – 90 1.4 – 2.5 54 54 10 255

90 – 160 2.5 – 4.5 60 60 12 305

160 – 220 4.5 – 6.2 72 72 14 355

200 – 260 5.7 – 7.4 84 84 16 405

250 – 320 7.1 – 9.1 96 96 16 405

416 - 880 11.8 – 25.0 120 120 20 510


Spill holes are incorporated into the parachute to provide stability in the descent. Swivels incorporated between the parachute and the shock cord allow the parachute to deploy effectively and reduce the possibility of the shroud lines from becoming tangled.

8. Rocket Design Considerations

8.1 Rocket Stability

The centre of gravity (Cg) and centre of pressure (Cp) and the relationship between them are key aspects in determining the stability of the rocket during flight. It is important to know where the two points are located on the rocket.

The centre of gravity is the point on the rocket at which the weight of the individual components

(called the gross lift-off weight or G.L.O.W) is balanced.

The centre of pressure is the centre of aerodynamic lift. This can be determined considering the

geometric layout of the rocket e.g. rocket length and shape/size/number of fins, shape of nose cone.

These can be determined using rocket design software. Alternatively, it can be calculated using

spreadsheets.

The Cp and the Cg must be marked on the rocket. As a general rule, the Cg must be at least one

rocket diameter (called the static margin) forward of the Cp i.e. the Cg must be closer to the rocket’s

nose than the Cp (generally by at least one rocket diameter) as shown below. If the separation is

closer than the rocket diameter, it could become unstable in flight and start to tumble. This can be

corrected by moving the Cg forward e.g.by adding weight to the nose cone) or by moving the Cp

backwards (by redesigning the rocket to add more or different shaped fins).

8.2 Pressure Relief Holes Medium and high power rockets fly higher than the low power counterparts. Because of this, the rocket will experience changes in atmosphere pressure as it rises to the greater altitude i.e. the outside pressure reduces. If the pressure inside the rocket is not equalised with that of the outside atmosphere, the nose cone can be ejected earlier than planned. This can happen when the rocket is travelling at high speed. The parachute can deploy early thus causing the rocket to turn sideways. Extensive damage can occur to the rocket body, parachute, fins etc.

Cp Cg

d

This distance ≥ d

Where d = diameter of the rocket


It is also important that the altimeters in the AV bay to be exposed to the correct external air pressure for them to work effectively when used for deployment purposes. This is particularly apparent with rockets with larger diameters e.g. 100mm and above. To reduce the effect of the pressure variation, small holes can be drilled into the upper airframe below the nose cone to equalise the internal pressure as the rocket ascends. The number and diameter depends on the volume of air inside the rocket cavity. As a rule of thumb allow ¼” hole for every 100 cu in of internal air space.

Small holes can also be drilled into the AV bays to prevent similar pressure differential.

9. Flight Records and other Data Rocketeers are encouraged to keep;

A folder containing all of the relevant information about the rocket/s. (This is helpful when

filling out flight cards.)

Simulation data that will assist in determining the expected height for the rocket launch

given the weight and motor thrust and impulse details

A log of their launches including weather conditions, rocket performance (launch, flight,

deployment), delay timing performance, recommendations for future

Pressure relief hole drilled into the AV bay

Pressure relief hole drilled into the upper airframe


It would also be appropriate to develop and utilise a checklist to assist in the process of prepping the rocket for launch. This will assist in ensuring that the flight is successful e.g. all components have been incorporated/assembled, the electronics are armed, batteries are charged and connected.

10. TRA Certification

For the beginner rocketeer, it is important to understand that there is a pathway through the levels

of rocketry from beginner through to advanced. It could be considered as a ‘career path’.

In general, rocketeers progress through three different stages of rocketry: low-power, mid-power

and high power. Many rocketeers are happy to stay with low or mid-power rocketry for their

careers and that is OK. There is no pressure to progress through more advanced stages. However,

for those interested in advancing through the various classifications, there is a well-developed

support structure available both informally through the AusRocketry forum and mentor scheme as

well as formally through the TRA guidelines and certifications.

For high power rocketry, TRA have developed a three level system to facilitate a structured

progression from beginner through to advanced rocketeer. Level 1 is the basic level with level 3

the highest level. This system is recognised internationally. At each stage, the rocketeer must

undertake evaluations and pass an assessment process administered by the TRA prefect. For each

level attempted, the rocketeer must complete an application form and submit to the TRA prefect

before evaluation can commence.

The QRS has adopted this system of certification.


The three certification levels for high power are described in the table below in general terms.

Power Level Description Rocket

Motors

Other

Requirements

Low - Low powered rockets

A – D Use ‘green’ launch cards at QRS launches

Mid - Mid powered rockets E - G Use ‘yellow’ launch cards at QRS launches

High 1 Motor impulse up to 640 N.sec

Rocket built by flyer (kit or scratch built)

Certification flight observed by TRA prefect or TAP member

Electronics not required

Recovery system deployment must operate

Rocket must be recovered without major damage

H – I Obtain Qld Explosives licence from Natural Resources and Mines

Join Tripoli Rocketry Association

Use ‘yellow’ launch cards at QRS launches

High 2 As for Level 1 except:

Motor impulse up to 5120 N.sec

Must complete a written test

J - L As for Level1 except:

Obtain Qld Explosives licence ‘alter’

Maintain log book for explosives licence justification

Encouraged to obtain RSO/LCO accreditation

Act as RSO/LCO at scheduled launches

High 3 As for Level 2 except:

Motor impulse greater than 5120 N.sec

Electronic device as primary means of recovery

Rocket design approved by 2 TAP members o Pre-flight data capture form o Rocket drawings showing rocket

components o Parts listing o Electronics wiring diagram o Pre-flight check list detailing assembly

M +


11. Helpful Websites and Resources

Listed below are some helpful websites. There many others. These are just a selection.

Aerotech http://www.aerotech-rocketry.com/ US based manufacturer

Apogee http://www.apogeerockets.com/ US based manufacturer

Educational newsletters

AusRocketry forum http://ausrocketry.com/forum/ Australian based forum

AusRocketry Shop http://ausrocketry.com/shop/ Australian based distributor

Estes Rockets http://www.estesrockets.com/ US based manufacturer

LOC / Precision http://www.locprecision.com/ US based manufacturer

Public Missiles Ltd http://www.publicmissiles.com/ US based manufacturer

Queensland Rocketry http://www.qldrocketry.com QRS web site

Qld Rocketry Society Forum http://www.ausrocketry.com/forum/viewforum.php?f=13

Tripoli Rocketry Association http://www.tripoli.org/ US rocketry organisation

Wildman Rocketry http://www.wildmanrocketry.com US based manufacturer

Vern’s Rocketry Web Site http://www.vernk.com/ US based Rocketeer

Wikipedia http://en.wikipedia.org/wiki/MainPage Internet encyclopaedia

UK Rocketry Handbook http://www.ukra.org.uk/docs/youth/RocketryHandbookV1.2.pdf

The Wikipedia site can be used for research issues relating to rocketry e.g. aerodynamics, drag

coefficient, model rockets, nose cone design

There are two model rocketry simulation software programs available as follows:

Rocksim Apogee Rockets (may be purchased after a free trial period)

Open Rocket (free to download and use) - Available from http://openrocket.sourceforge.net/

http://www.aerotech-rocketry.com/

http://www.apogeerockets.com/

http://ausrocketry.com/forum/

http://ausrocketry.com/shop/

http://www.estesrockets.com/

http://www.locprecision.com/

http://www.publicmissiles.com/

http://www.qldrocketry.com/

http://www.ausrocketry.com/forum/viewforum.php?f=13

http://www.tripoli.org/

http://www.wildmanrocketry.com/

http://www.vernk.com/

http://en.wikipedia.org/wiki/MainPage

http://www.ukra.org.uk/docs/youth/RocketryHandbookV1.2.pdf

http://openrocket.sourceforge.net/


Appendix A – Typical Reloadable Motor System (Source: Aerotech Consumer Aerospace Catalogue).


Appendix B – Typical Motor Designation (Source: Aerotech Consumer Aerospace Catalogue).

Information Pack for Mid Power Rockets · 2013. 10. 16. · Ejection The act of separating the...

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