Most model rockets blast off at a much higher acceleration rate than full size rockets. Is it possible to have model rockets take off slowly to more closely mimic the acceleration speed of full scale rockets?
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Model rockets accelerate quickly because they have a higher thrust-to-weight ratio. So you need to put a less powerful rocket engine in them or increase the weight.
Increasing weight will rescue the max attitude they fly to.
If you reduce the trust and amount of fuel you burn the same the altitude will decrease a bit because of an increase in gravity lost. More work is needed to be done if to counteract gravity if the flight time is longer.
After a look at model rocket engines, it looks like their burn time them is less than 3 seconds for smaller variant. I am not sure why but I suspect it is simpler to manufacture them that way but it might be regulated.
If you look at rocket artillery that is in size a lot more comparable to a model rocket they have an engine burn time of similar short duration and will accelerate quickly, so the conclusion is for small scale rockets short burn time and high acceleration is more efficient.
As a comparison, a the space shuttle solid booster had a burn time of 2 minutes
There is a couple of reasons to keep large rocket acceleration down.
One is so even when most fuel is used do like to keep max acceleration at around 3g to protect the crew. Even for satellites they and the rocket would need to be stronger and heavier for higher acceleration.
Another reason is to keep speed and therefore drag down in the lower part of the atmosphere so use the fuel you have more efficiently. The drag also results in a lot of forces on the rocker you like to reduce.
small rockets are stronger than large ones because of the cube-square law and do not have weight-sensitive payload. So one of the major reasons larger rockets accelerate slower is not relevant.
That said there is a larger rocket that accelerates very quickly the https://en.wikipedia.org/wiki/Sprint_(missile) it was an anti-ballistic missile accelerated at 100g and no model rocket is close. There was even an experimental HIBEX low level interceptor that accelerated at 400g
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