|
Episode: Plywood Parachute Original Air Date: October 13, 2004 Myths: Plywood Parachute, Beat the Radar
Myth: Plywood Builder
A construction worker was on the top of a building holding a 4 ft. by 8 ft. piece of plywood on a windy day. The wind picked him up and carried him over the edge. Amazingly, he was able to hold on to the plywood and managed to steer himself so he landed on a lower floor unharmed.
Action/Results: Adam and Jamie determine the best way to start is by conducting scale model tests with a toy action figure. The action figure is named ìMini Buster.î Mini Buster is the right height, but Adam calculates that he is 6 feet tall and weighs 190 pounds, that is 2.5 pounds per inch, so the model needs to weigh 25 pounds. He then rethinks his calculation and determines volume is the key. Mini Buster is the correct weight. They also weigh out a 4 ft. by 8 ft. piece of plywood to determine how much the scale plywood should weigh.
At the shop, they drop Mini Buster off a crane both with and without the plywood in front of a scale rule. They determine that the plywood slowed the fall by 25%, but the fall would still be fatal. Since the myth is based on 5-ply plywood, they decide to test arrangements of five 4 ft. by 8 ft. sheets of single ply wood. After several tests, they determine that a rotating wing and a parachute design are the best bets to try at full scale.
To make Buster hold on to the plywood, his hands are replaced with clamps. Adam and Jamie also decide to make their own G force meters out of miniature globe light bulbs filled with red paint and sealed with tape, then placed in 2 sugar scoops. The bulb is supposed to break if Busterís head exceeds 80 Gs for 32/1,000th of a second. They test lethal and non-lethal impacts and the G meter works.
The test site is Hamilton Base, which closed in 1976 and is about an hourís drive north of San Francisco. The 60-foot tall control tower will be used as the drop point. They decide to try several fall scenarios.
The first fall is unassisted. It was determined that Buster hit the ground at 34 to 35 miles per hour at the time of impact. The G meter was shattered.
The second attempt involved an umbrella. The umbrella kept Buster upright and he had an impact of 38 MPH. The globe was broken, but not as badly as the unassisted fall because Busterís body acted as a shock absorber, lessening the impact to his head.
The next attempt was with a picnic umbrella. Busterís impact was slowed to 29 MPH, but not enough to save him.
A parachute was then used. The parachute did not fully deploy, but slowed the impact speed to 28 MPH. Again, it wasnít enough to save Buster.
Next, they try the plywood myth. Buster lands at 36 MPH, so the myth is busted, but they still have more testing.
Adamís parachute design wasnít very successful and it flipped upside down. ìFat lot of good that did,î he says.
Finally, they test Jamieís rotating wing. The wing caused Buster to fall off course and the high speed camera didnít capture the fall, but the glass ìball of deathî was shattered.
They now decide to test the second half of this myth: can you steer your fall using plywood?
For safety they connect a cable to the tower and the crane with a moderate incline to form a zip line. They put on padding, hold on to the plywood and try to steer during their controlled descent. After trying to steer with plywood during the fall, Adam says ìForget about controlling this thing. Thereís no control.î Jamie had even less control than Adam.
Myth Busted.
Myth: Canít Beat the Speed RADAR
The Build Crew (Scottie, Kari, and Tory) set out to test popular beat the RADAR myths.
Their goal is to test most practical RADAR myths in a legal fashion. They start with a RC model car that the RADAR can see and that tops out at 6 MPH. The myths are based on 2 types of speed guns: 1) RADAR, which sends out a microwave that hits a target and bounce back at a slightly different frequency; and 2) LIDAR, which sends out 1,000 infrared signals a second and measures the distance between each signal.
RC Car Test 1: Blue Paint
A blue shell is placed over the car. This is supposed to reflect the infrared at a different frequency and confuse the LIDAR. It did not work.
RC Car Test 2: Prism Tape
A shell covered with prism tape was placed over the RC car. It actually increased the visibility of the car to the RADAR.
RC Car Test 3: Aluminum Foil
The RC car was covered with aluminum foil. This also increased the RADAR visibility of the car.
RC Car Test 4: LEDs
Infrared light emitting diodes (LEDs) were placed on the RC car. The infrared is supposed to confuse the LIDAR, which also uses infrared. There was no effect on the LIDAR, but the RADAR didnít pick up the car as soon as it did in other tests.
RC Car Test 5: RADAR Absorbant Paint
This paint is very expensive, heavy and has the consistency of frosting. The paint was too heavy for the RC car to move.
Based on the tests, they go to the California Highway Patrol Academy with Earl the Caddy to test out more RADAR beating myths.
Myth 1: ìDumbî Ideas
The first test is all of the ìdumbî ideas at once. They will hang a CD from the rearview mirror, hang a disco ball and jiggle keys. Officer Rick Hatfield with the California Highway Patrol Academy informs them that the CD and disco ball are illegal because the driverís view is obstructed. This myth, as well as the others, will be tested at slightly below 50 MPH. None of these objects had any effect on either the LIDAR or RADAR.
Myths Busted.
Myth 2: Aluminum Foil on the Hub Caps
The hub caps were covered with aluminum foil. This had no effect.
Myth Busted.
Myth 3: Cover Entire Car in Aluminum Foil
Earl the Caddy was covered in foil with only the windshield exposed. Kari predicted that the foil would turn the car into a giant reflector. The RADAR did, in fact, pick up the car sooner.
Myth Busted.
Myth 3: LEDs
A license plate cover with 300 LEDs was placed on Earl. This had no effect.
Myth Busted.
Myth 4: Magnetron Guns
The magnetrons from microwaves are supposed to be near the same frequency as the K band of RADAR and may be used as a jammer. This had no effect.
Myth Busted.
Myth 5: Aluminum Chaff Gun
A fire extinguisher was used to propel aluminum foil pieced out of a tube supposed to confuse the RADAR. This had no effect and they were told that a littering ticket is more expensive than a speeding ticket.
Myth Busted.
Myth 6: Mirror on Wheel of Death
A plywood rotating disc was covered with a reflective material and rotated during driving. This was supposed to change the signal of the RADAR. There was a minor effect on the RADAR, but it still worked.
Myth Busted.
Myth 7: Matte Black Paint
Earl the Caddy was painted matte black. This had no effect.
Myth Busted. |
Episode Descriptions 
