Recent Comments

6 Things to Know About Launching Water-Bottle Rockets

SAFETY FIRST: Ask an adult to help with tools you haven't used before.

Did you know you can launch a rocket in your backyard using only an empty plastic bottle, water and a launchpad?

Unlike engine-powered rockets, water-bottle rockets don’t pose a fire risk and often require less prep. These DIY rockets still pack a powerful launch and should be treated with caution.

Here’s how water-bottle rockets work: an adult opens a valve, allowing compressed air to surge into the bottle, sending the rocket into the air. A little water inside the rocket helps push it higher. It’s a fun example of science — showing how every action has an equal and opposite reaction.

Read on to prepare for your own, epic launch.

Here’s What You Need to Know About Water-Bottle Rockets

  1. You need a launcher. While the rocket itself is a breeze to build, your launchpad requires a little more thought. Some people decide to build their own launchers out of PVC pipe or other tools from a hardware store (NASA has instructions you can take on with the help of an adult). We like this ready-made launcher from AquaPod. A great launcher can be used over and over again so it’s well worth the investment.
  2. The secret to making a high-flying rocket is finding the right balance of materials, weight and design. Rockets with a perfect balance can soar more than 100 feet in the air.
  3. Decorations need to be lightweight and nonmetallic. If they fall off in the air, you don’t want heavy metal pieces coming down near anyone.
  4. Don’t use small bottles made out of thin plastic. The pressure builds so much that it could make those bottles explode on the launch pad, which is why it’s important to never hold the bottle when pumping it with air.
  5. Stand back. Always launch your rocket while standing at least 15 feet away, and shoot them off in an open area so they don’t land on you. Don’t look directly over your rocket on the launchpad. Here’s some great information on staying safe with water bottle rockets.
  6. Check out the video above where we show you how to decorate your water-bottle rocket and what a launch looks like.


If you’ve ever launched a water bottle or engine-powered rocket, we’d love to see photos and videos. Tag us on Instagram or upload a photo using the form below.

Submit a Photo of Your Project

Important Note: Please only upload photos of your project. Because of privacy rules, we can't post any photos that show people's faces. Always ask for your parent's permission before uploading anything to a website.

6 Comments on 6 Things to Know About Launching Water-Bottle Rockets

  1. I need tips for a long distance rocket

  2. WHy does it have 2 be one third

  3. Scoutmaster 0518 // September 5, 2020 at 6:43 pm // Reply

    Ideal bottles are 1 liter and 2 liter soda bottles, sparkling water bottles or similar…plain water bottles may be a bit wimpy and not take enough pressure….they may split

  4. Scoutmaster 0518 // September 5, 2020 at 6:40 pm // Reply

    I have done this as a Science Teacher. A very snug fit between the bottle neck and the launcher tube allows a higher pressure and higher altitude. Do this with one or more layers of “Scotch Tape”
    Fins: Make sure you have “enough” fin area. To test attach a length of string to the balance point of your rocket and do a swing test….swing it overhead at the end of a 6′ length of string….if it is stable you are good to go if not bigger or more fins are needed.

  5. This is not a shooting sport. Range officer not necessary.

  6. You might check shooting sports manual, my guess would be a unit doing this…including a wood badge troop…need a range officer to inspect the area first.

Leave a Comment

Please don't use your real name.