Provided they are kept in a dry, cool, and stable environment, they should last indefinitely. The ingredients are non-volatile, so they do not really degrade over time.
If you want to know how long they burn for, you need to look at the rating on the side of the rocket. A higher thrust number means that it will burn for a shorter amount of time. Most small model rocket engines burn for 3 to 5 seconds.
It depends on the motor. They are all rated in power and length of 'burn'
I have built one 4 inches long, it worked well with a 1/2A motor.
It depends on what type of rocket you are building.
Burn time in a solid rocket motor refers to the duration during which the propellant burns and produces thrust. It is a critical parameter that determines the total impulse produced by the motor and the overall performance of the rocket. Longer burn times usually result in higher speeds and altitudes for the rocket.
In a real rocket, there is short a time in atmosphere and the aerodynamics are less important. In a model rocket, all flight in the atmosphere and the aerodynamics are very important. In a real rocket, it has a liquid or solid rocket engine and a large propellant mass fraction. In a model rocket, it has a solid rocket engine and a small propellant mass fraction . In a real rocket, there are four forces during atmospheric flight. In a model rocket, there are four forces throughout flight. In a real rocket, there is a long powered flight . In a model rocket, it has a very short powered flight . In a real rocket, it has passive stability and active control . In a model rocket, it has passive stability and no control. In a real rocket, it has expensive materials such as aluminum, titanium, and nickel alloy. In a model rocket, it has inexpensive materials such as balsa, cardboard, and plastic. In a real model, there is a high speed and the heating is very important. In a model rocket there is low speed and the heating is not important.
They will usually last just as long as a Toyota or Honda.
To build a model rocket you will need a chemical rocket engine, some cardboard tubes, glue, a long rubberband, a garbage bag and a lot more. You can find a complete list of supplies here: http://www.ehow.com/how_2308899_build-model-rocket.html
till fuel lasts. they are using algae
The motor in a S10 Blazer can last for many years. It will really depend on how well the vehicle has been taken care of. With proper maintenance, the motor can last more than 200,000 miles.
A variable DC servo will last for some time. Just make sure to properly keep it maintained. Since the motor is a replacement for a clutch motor you should expect your motor to last a very long time. The motor comes with a full year warranty.
1975 Long shaft
The question is not well-formed. Similar questions may include: How many minutes does a helium balloon stay aloft? How long does a hot air balloon stay aloft? How long does a particular rocket motor burn?