Naval Warfare
The last semi-final pits the Law Dawgs against the Rocket Men in all-out war. The challenge is to build a torpedo. The difference between the junkyard-built torpedoes and naval torpedoes is that the junkyard torpedoes will be re-usable. Each team will have 5 attempts to shoot their torpedo across the length of a pool and hit their opponents boat (rather, a net mounted under their boat). There are obstacles in the pool so it won't be a straight shot and each team will be able to try and maneuver their boat out of the way of the torpedo.

The Law Dawgs are going to build a torpedo powered by a compressed gas which will drive a pump to propel their torpedo along.  The steer their torpedo around and through the obstacles, they will use small pistons and hand-pumps to turn their die planes up and down. Another system will turn the torpedo left and right. Speed will be a concern as will having enough tubing to reach from their boat to the other boat. Their biggest problem is time. They will only get 3 minutes of propulsion from each tank of compressed nitrogen.

The Rocket Men will be building a "traditional" torpedo. It will be a tube that houses 3 car batteries which will power 2 small fans and a propeller. One fan will control up and down motion, the other will control left and right movement.  The obvious problems will be weight and the water. Electrics and water are a bad combination. They'll have to make certain that their tube is water-proof.

The Rocket Men expert,
Joe Curran
The Law Dawgs expert,
the returning Greg Bryant
The Law Dawgs will be tethered to their
torpedo and control it hydraulically
The Rocket Men are going to wire
themselves to their electric torpedo
Get scrounging!
Under those hoses is a Law Dawg
This manure pump will propel the Dawgs'
torpedo. What is it with this team and
manure spreader parts?
A pair of radiator cooling fans will
provide steering for the Rocket Men's
The pump seems to pump more then
just manure...fortunately
Here comes da judge...
Rear Admiral Gus Gustavson
This trolling motor will propel the Rocket
Men's torpedo through the briny deep
Initially the Rocket Men were going to use
an R/C controller but decided to go with
a "hard wired" system
Greg fills the board with math
A proper torpedo body for NASA
Captain Mike enjoys a slurpee
This nozzle will provide thrust for the
Law Dawgs
A directional controller
The Law Dawgs perform a test
Later, the Rocket Men do the same
Oh No!  Only 5 minutes left!
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