Model Rocket Thrust Curves

A8 Model Rocket Motor

The total power of each model rocket engine with a letter designation is double the power of the previouse letter designation. For example the C engine is twice the power of a B engine and a B engine is twice the power of a A engine.

The A8 motor comes in 2 ejection charge delays of either 3 or 5 seconds. Most model rockets need the 3 second shorter delay. Only very light or small model rockets including upper stages of a two stage rocket can use the longer 5 second delay. The A8-3 is not recommend for rockets heavier than 2oz.

B6 Model Rocket Motor

This thrust curve shows the peak thrust during the start of the model rocket motor burn. As the model rocket motor burns the thrust drops to a lower sustaining thrust.

The B6 motor comes in 3 ejection charge delays of either 2, 4 or 6 seconds. Most model rockets need the 4 second delay. Larger model rockets of 3 ounces or more should use the shorter 2 second delay. Only very light or small model rockets including upper stages of a two stage rocket can use the longer 6 second delay. The B6 is not recommend for rockets heavier than 3-4oz.

C6 Model Rocket Motor

The second number 6 after the letter designation is the average thrust in newtons. While the peak thrust can be much higher than the sustaining thrust, the average thrust is beter indication of the model rocket engines weight lifting capacity

The C6 motor comes in 3 ejection charge delays of either 3, 5 or 7 seconds. Most model rockets need the 5 second delay. Larger model rockets of 3 ounces or more should use the shorter 3 second delay. Only very light or small model rockets including upper stages of a two stage rocket can use the longer 7 second delay. The C6 is not recommend for rockets heavier than 3-4oz.