Back to TCC Competition Primers

 

TCC NAR Competition Primer:  USMRSC Rule 33, Super-Roc Duration Competition (SRD)

 

 After you review this Primer, please support the TCC Competition Primer Project by completing this short survey. Thanks.

 

This primer presents, in one place, all the information you need to succeed in this event.

TCC has provided a link to the official rules whenever we discuss a rule.

 

All Entries

Your entry must:

* Comply with the NAR Model Rocket Safety Code: http://www.nar.org/NARmrsc.html USMRSC 2.2

* Be a model rocket as described by the United States Model Rocket Sporting Code. USMRSC 3.1-3.9

* Use NAR Contest Approved motors:  http://www.nar.org/SandT/NARenglist.shtml USMRSC 4.1, 4.4

* NOT eject its motor casing(s) without a recovery system. USMRSC 9.2

* Have your NAR number or your name on the outside, large and clear enough that the contest officials can easily read it. Teams must use the Team number or name. USMRSC 9.4

* Have been constructed by yourself or by one or more members of your Team. You may not enter Ready-To-Fly rockets (no construction required) in NAR sanctioned competition. USMRSC 9.9

 

Know the rules

Your having a grasp of the bigger picture can increase your enjoyment of NAR competition. You can read the Pink Book Lite to see only the rules for competitors, not for Contest Directors or other contest officials. Read the full USMRSC (Pink Book) to see all the rules.

* Pink Book Lite:  http://ojames3.tripod.com/tccnarcontesttips/USMRSCLight.html

* Full USMRSC:  http://www.nar.org/pinkbook/

 

General Competition Tips:

TCC NAR Competition 101

TCC NAR Competition Strategy and Tactics

Contest Etiquette by Kevin Paul Wickart, NAR 59720, cr 1998, the author

Beginning Competition -- The RSVP Principle by Kevin Paul Wickart, NAR 59720, cr 1998, the author

Guide to NAR Contest Rocketry Information for Beginners by Jeff Vincent, NAR 27910, Northeast Regional Contest Chair

 

Which are the Main USMRSC Rules for This Event?

* The main rules are 9, 15, and 33.

http://www.nar.org/pinkbook/9_Entries.html

http://www.nar.org/pinkbook/15_Timing_Data.html

http://www.nar.org/pinkbook/33_SRD.html

* This event can be flown as Multi-Round.

 

What is the Goal?

The goal of Super-Roc Duration Competition (SRD) is to attain the longest flight time with the longest rocket  -- a single stage model rocket the length of which is equal to or greater than the minimum length for the event class you enter. USMRSC 33.1

 

Are There Any Special Considerations?

* SRD is divided into event classes based on the total impulse for the class, with each event class having a minimum and maximum length. Your entry may be longer than the event class maximum length, but contest officials will not award points for excess length. USMSRC 33.5

Motor

Min (cm)

Max (cm)

Min (inches)

Max (inches)

1/8A

12.5

25

4.9

9.8

1/4A

25

50

9.8

19.6

1/2A

50

100

19.6

39.4

A

75

150

29.5

59.0

B

100

200

39.4

78.7

C

125

250

49.2

98.4

D

150

300

59.0

118.1

E

175

350

68.9

137.8

F

200

400

78.7

157.5

G

225

450

88.6

177.2

* Also, Contest Officials will not allow your entry if the body or significant structural parts are made from hard or potentially unsafe material (e.g., hardwood doweling or fiberglass shaft), under the provisions of Rule 1.1. USMRSC 33.3

* Your entry must be single stage, but can be clustered. USMRSC 33.1

* If your entry is clustered, the sum of the total impulse of the motors you use cannot be more than the total impulse limit for the event class you are flying. USMRSC 4.6, 4.8, 33.5

* If your entry is clustered, enough motors must ignite to meet the impulse limits for the event class you are flying. USMRSC 4.6, 4.8, 33.5

* This event can be flown as Multi-Round.

 

Do I Have to Return My Entry?

* You must return your entry after at least one qualified flight in order to place in 1st-4th. USMRSC 15.10, 13.1

* If you cannot return your entry after at least one qualified flight, you’ll only get Flight Points. USMRSC 13.1, 13.4, 13.5

* The Contest Director can require that you return your entry. USMRSC 9.10

 

How Many Flights Can I Make?

* You can make up to two flights. USMRSC 10.1

* You can use more than one model. USMRSC 9.7

 

How is the Competition Scored?

Short Answer:  Entry’s length in centimeters (from nose tip to motor nozzle) times flight duration in seconds. If you make two qualified flights, the scores of the two flights will be added together to get your final score. USMRSC 10.1, 33.4

 

Long Answer: SRD scoring has two point types: static points and flight points. Contest officials will multiply the static and flight points for each official flight to determine your entry’s score. USMRSC 33.4

Static Points: Contest officials will measure your entry from the tip of the nose cone to the nozzle of the motor and award 1 point per centimeter up to the maximum length for the event class. USMRSC 33.4

Flight Points: Contest officials will award 1 point for each second of duration. USMRSC 33.4

Example: If the event class is A SRD, the maximum length is 150cm. If your entry is 155cm from nose cone tip to motor nozzle, contest officials will award 150 static points. If your entry then achieves a flight of 366 seconds, contest officials will award 366 flight points. Your entry’s final score is then the static points multiplied by the flight points:  150 x 366 = 54900 points.

 

What Will Disqualify My Entry?

* Your entry will be disqualified if it separates into two or more parts or ejects the motor(s). USMRSC 15.2

* Your entry may be disqualified if, in the opinion of the contest officials, it does not comply with the competition rules or is unsafe in operation. USMRSC 11.1, 11.2

* Your entry will be disqualified if it comes apart, bends so as to crimp the body, or has a similar structural failure prior to ejection. USMRSC 33.2

 

How About Some Suggestions for New Competitors?

General:

DO NOT use any hard materials such as dowels, rods or fiberglass reinforcing. Use the same cardboard, paper, balsa, light wood and plastic that you would for any other contest model.

 

One of the main points to remember is that you do NOT have to build an entry that is the maximum length for the event class. If your maximum length SRA entry crimps or comes apart, you get ZERO points. For event classes D SRA and above, you should consider building an entry that is less than the maximum length. Instead, use a combination of a larger body diameter than minimum and a shorter length than maximum. When you join tubes together, use a coupler that is at least two body diameters long. For example:

http://ojames3.tripod.com/bpcmr/index.album/g-srd-model-three-estes-e9-motors?i=4&s=1

 

Test your model to ensure that it operates safely and as intended. Remember, you don’t have to use more than the minimum impulse allowed. For example:

http://ojames3.tripod.com/bpcmr/index.album/g-srd-model-thunderbird-g-a-black-powder-g-three-estes-e9-motors?i=6&s=1

 

Kit Selection:

You won’t find many kits suitable for SRD in you local hobby store. Determine the minimum length for the event class and pick the lightest kit that is over the length for the event class. For example …

You can “kit-bash” (use the parts from one or more kits) two Estes Skywriters into one A SRD.

You can “kit-bash” two Estes Blue Ninjas into one C SRD.

The Estes Mean Machine is suitable for D and E SRD.

 

Commercial kits are available for 1/8A, A-G SRD. For 1/4A and 1/2A SRD, you can “kit-bash” an entry by using parts from more than one kit or adding parts you already have to a kit. Qualified Competition Rockets has kits for 1/8A, A, B, C, and D SRD.  QCR’s D SRD is also long enough for E, F and G SRD. You can add an extension to the QCR or ASP 13mm parachute duration model to make a rocket long enough for 1/4A, 1/2A and A SRD. ASP sells 13mm tubing and bulkheads. Just glue the bulkhead half way into a 30 inch extension tube, insert the existing nose cone into the other end and use the assembly as the nose cone for your 13mm PD model.

 

Motor Selection:

A rocket with a diameter of 0.5 inches to 0.75 inches will usually be best for 1/8A to A. The 0.5 inch 1/4A, 1/2A and A motors will usually be your best choice. For B and C PD, 1 inch diameter rockets will be competitive and easier to prepare. Select a delay time such that ejection occurs as high as possible. Use a computer simulation (wRASP32  http://www.mrhq.org/digdug/wRASP32/wRASP32.shtml) to help you select the best delay time. APCP motors will usually fly higher than black powder, but are more expensive and don’t work as well with piston launchers.

 

Parachute Selection:

Your parachute must deploy (eject and open) if you are to get the best possible duration. Use a rocket with the smallest diameter in which you can pack a parachute that will reliably deploy. Use the largest parachute that you can pack into your rocket and still have reliable deployment. Lightly dust the parachute on both sides with talcum powder before you fold and pack it (http://ojames3.tripod.com/tccnarcontesttips/BobKaplowNAR18LCompParachute.pdf).

 

Many vendors have Super-Roc Duration models and/or competition supplies:

http://ojames3.tripod.com/tccnarcontesttips/competitionrocketvendors.html

 

What Else & What Next?

Super-Roc Theory and SR Plan:

http://www.rocketrycarolina.org/index.cgi?ltros=730

 

TCC NAR Competition Bibliography

http://ojames3.tripod.com/tccnarcontesttips/TCCNARCompArticleBib.html

 

Yahoo group for discussing model rocket competition:

http://groups.yahoo.com/group/contestRoc/messages

 

Use computer simulations to determine altitude and sink rate for various rocket/motor/parachute combinations.

* Free altitude simulations: 

wRASP - http://www.wrasp.com/

wRASP 32 - http://tccnar.tripod.com/sims/082_wRASP32_221.zip

* Free sink rate simulation:

http://www.onlinetesting.net/cgi-bin/descent3.3.cgi

 

You can get some useful info from the International Model Rocketry Competition site:

http://www.spacemodeling.org/new/home.html

 

Aerospace Specialty Products Streamer and Parachute Tips:

http://www.asp-rocketry.com/model-rocket-tips.cfm

 

George Gassaway’s Competition Tips – Take No Prisoners!

http://tccnar.tripod.com/tcctnp/

 

Detecting Thermals:

http://www.apogeerockets.com/education/detecting_thermals.asp

 

rmr Frequently Asked Questions – Part 9: Competition and Records:

http://www.ninfinger.org/rockets/rmrfaq.9.html

 

 

Back to TCC Competition Primers