Air Impulse Rocket - as constructed by Bill Franklin, modified by the Flying Bernoulli Brothers
A low mass rocket is launched by the brief impulse provided by air pressure from stomping on a bladder (2-liter bottle). The effects of varying rocket length and mass, angle of launch, and bladder capacity can be explored. The device is similar to a commercial toy stomp rocket.
Warning! This apparatus could cause injury to user and others around it if not used properly. Students should be properly supervised and instructed of possible dangers before use.
Materials
Materials List
| Quantity |
Item |
| one |
8 to 10 inch length of Shower rod cover |
| one |
1 inch by 6inch strip (nose cone) 1/8 polyethylene foam packing material |
| one |
2 inch by 4 inch strip ( tail fins) 1/8 polyethylene foam packing material |
| two |
10 inch lengths 1/2 " PVC plastic pipe (SCH 40 - 600 psi drinking water pipe) |
| one |
1/2" PVC elbow |
| one-two |
1/2 in conduit strap |
| one |
hose clamp (worm gear type) ( be sure it fits over end of 2-liter bottle opening) (or you can just use duct tape) |
| two-four |
1 inch dry wall screws (use four screws if you use two conduit straps) |
| one |
1 foot length 2 x 4 lumber |
| one |
2 liter pop bottle - empty |
| 1 ft |
electrical or masking tape |
| 1 |
hot melt glue and glue gun |
Assembly
Launcher
- Cut two ten inch lengths of PVC pipe. Join at right angle with PVC elbow.
- Attach one side of pipe to 2x4 base with conduit strap and dry wall screws.
Be sure to allow end of pipe to overhang 2x4 by 2-3 inches.
- Attach 2-liter bottle to end of pipe with hose clamp or duct tape.
Rocket
- Cut one 8 to 10 inch length of closet rod cover using a hack saw.
- Slip rod over PVC pipe. Use masking or electrical tape to seal off side of closet rod.
Do not snug rod too much - it must slip easily over the pipe.
- Roll up 1 inch by 6 inch strip of foam packing. Stuff the roll into one end of the
closed rod, leaving 1/2 inch of foam protruding from end of curtain rod. This will be the
safety nose cone. Tape it to the curtain rod body of the rocket
- Cut fins from remaining 2 in by 4inch portion of foam packing. You can choose the
size and number of fins. Try 2 or 3 fins, large or small. Try fins on the front of the
rocket. If you do not attach some sort of fins, the rocket will begin to tumble immediately after launch.
- The rocket is ready to be launched.
ALWAYS LAUNCH THE ROCKET OUTDOORS IN A CLEAR AREA.
Operation
- Slip rocket onto the launcher
- Put one foot on the side of the launcher away from the bottle to steady it. Or have
another person steady the launcher with their foot.
- ANGLE the launcher AWAY from your face and away from other people/animals,
and objects.
- Be sure any other person is behind you and out of the line of flight.
- Stomp the 2 liter bottle with your other foot!
- Try different angles to get greater distance or altitude.