Aluminum fins allowed at Tripoli launches ???

[Finicky]

Folks,

I help coordinate all college team launches at our field (URRG in Potter, NY). All launches are operated under Tripoli research launch rules.

For every college team launch it is basically guaranteed that the rocket will contain something "unusual", and so I need to make a judgement call about whether to allow the rocket to fly at our field.

I have a team that wants to fly a rocket on a K1440 that has aluminum fins. I have read the special note on the Tripoli website regarding metal in rockets. What I am focusing on is the following wording:

"1-3 Definitions, High Power Rocket, (e) -- (High Power Rocket) That is made of paper, wood,
fiberglass, or plastic with a minimum amount of metallic parts necessary for airframe integrity"

By my interpretation, using aluminum on the fins violates the spirit of using a "minimum" of metal, since the fins could easily been made out of wood or fiberglass.

What do people think ? I hate to turn teams away, but if everyone agrees that this is clearly a no-no then I will have to tell them.

Thanks

 

[jderimig]

I am biased because I am using an aluminum fin rocket for an extreme Balls flight but would like to test fly it with an less extreme profile either at Potter or Geneseo.

But if you add up all the metal mass of the rocket in question including motor case, eyebolts, threaded rod etc, how much percentage does alum fins add to the total metal content of that rocket?

 

[heada]

Can it fly safely with a different material? Does having the Al fins meet some goal that couldn't be met otherwise? What was their justification for using Al over anything else? Thy why is the most important part in my eyes since they're not blanket banned.

 

[jbr]

AL is much easier to hold up in mach and cheaper than carbon fiber
yes AL fins are allowed as is an AL fin can

 

[Nytrunner]

I have a team that wants to fly a rocket on a K1440 that has aluminum fins. I have read the special note on the Tripoli website regarding metal in rockets. What I am focusing on is the following wording:

Sounds like a test flight on a lower powered motor. If they're using a more powerful motor for the actual competition, that could explain the metal fins.

 

[MClark]

Ask the launch organizer what would be allowed. Some places have local restrictions to make the land owner happy.
i can’t imagine a rocket on a K1440 "requiring" metal fins.

M

 

[jbr]

such as Kloudbusters do not allow all aluminum rockets

 

[jderimig]

such as Kloudbusters do not allow all aluminum rockets

On the outside....

 

[Hybrid33]

Kloudbusters allow Aluminum fins and fin cans . They can not be attached to the motor case they need to be attached to the body tube .