Whats the altitude achieved by each type of motor?

Hi. After searching on google regarding this topic, I did find calculations regarding the altitude achieved by rockets but I couldn't find an exact link related to this topic. I do know that there are several factors influencing the altitude gained by the rockets. But, I just want a rough idea or estimations from your experiences on what altitude each motor can deliver.

I had a D12 motor that only achieved an altitude of 2 feet.

"US NATIONAL MODEL ROCKET PERFORMANCE RECORDS"
https://www.nar.org/contest-flying/records/#nar-records-div

The "C" Div (adults) and "D" division (Teams) tend to be the highest records of the A-B-C-D age divisions (note, age divs, not motors).

You won’t find an exact link to that topic. Sub minimum diameter rockets will give you the greatest altitude but weight/fin design/NC will all effect altitude in addition to your motor choice. I suggest you start by downloading open rocket or RASaero II, design your rocket and choose every imaginable motor you can fit in that rocket. There is no textbook answer for what you are asking.

Mushtang said:

I had a D12 motor that only achieved an altitude of 2 feet.

Click to expand...

wow. Thats like nothing.

RocketEnthusiast101 said:

wow. Thats like nothing.

Click to expand...

Well, it exploded at that altitude so it stopped gaining. Your mileage may vary.

RocketEnthusiast101 said:

But, I just want a rough idea or estimations from your experiences on what altitude each motor can deliver.

Click to expand...

Similar to your "how much thrust to reach 100km" question, the answer depends on many factors.

A 24mm E motor by estes will go only ~90 meters in a 75mm diameter rocket because of the increased size and drag (and probably heavier). Put the same motor in a 29mm diameter rocket and it will go almost 400m because it has less drag (and probably less weight).
As suggeseted above, experiment in thrustcurve to get an idea of how high certain rockets will go with various commercial motors https://www.thrustcurve.org/guidepage.jsp

It's good that you are asking questions, but it would be beneficial to simplify the questions and start with the basics: How does a solid rocket motor or liquid rocket engine work (and what's the difference between them)? What forces act on a rocket vehicle during flight (how do you keep it going straight, what conditions will it experience, etc)?

RocketEnthusiast101 said:

Hi. After searching on google regarding this topic, I did find calculations regarding the altitude achieved by rockets but I couldn't find an exact link related to this topic. I do know that there are several factors influencing the altitude gained by the rockets. But, I just want a rough idea or estimations from your experiences on what altitude each motor can deliver.

Click to expand...

More than anything, it depends on the weight of the rocket you put it in. But A, B, C Estes rockets can weigh anywhere around 50 to 100 grams, and that’s a 100% factor.

To compare apples to apples, see the NAR records chart where rockets have been optimized.

To compare oranges to oranges, look up a specific rocket and its own specs.

georgegassaway said:

"US NATIONAL MODEL ROCKET PERFORMANCE RECORDS"
https://www.nar.org/contest-flying/records/#nar-records-div

The "C" Div (adults) and "D" division (Teams) tend to be the highest records of the A-B-C-D age divisions (note, age divs, not motors).

Click to expand...

That's a good start. Back in the day, before Open Rocket etc., when HPR was young, some people produced "waiver tables", or some such thing, so that RSOs could easily check if a rocket and motor would stay below the fields waiver altitude. I never flew HPR and I don't have these tables, but they could be hunted down.

Doesn't TRA keep altitude records per motor class? Are those publicly available or to members only?

heada said:

Doesn't TRA keep altitude records per motor class? Are those publicly available or to members only?

Click to expand...

https://tripoli-records.org/records/single.html

Our group had a “C Challenge” some time ago. This was based around a scratch built minimum diameter model with a C6-5 BP motor. It had to carry an Alt 1 or 2 to record the apogee. Two of these models exceeded 1700’ and 1900’. Not bad for a C motor! Both these models achieved close to the simmed altitudes.

Mine achieved the 1900’ apogee because I stripped the Alt 1 from its case so it could just fit in the nosecone and further reduce the mass.

Easiest way to achieve the highest altitude possible with a a rocket motor is to epoxy some fins and a nose cone right onto the motor. Boom, nothing will go higher than that with that motor.

Yukon@K-9 Rocket Tech said:

Easiest way to achieve the highest altitude possible with a a rocket motor is to epoxy some fins and a nose cone right onto the motor. Boom, nothing will go higher than that with that motor.

Click to expand...

I suspect that is not true... both drag and weight play a factor. The rocket you described would have minimal weight, and thus drag would be a major factor limiting altitude. The least draggy rocket might not be one with fins and NC glued to the motor, and added weight can sometimes increase altitude. I could run some sims to prove this, but I'll leave that as an exercise.

Kelly said:

I suspect that is not true... both drag and weight play a factor. The rocket you described would have minimal weight, and thus drag would be a major factor limiting altitude. The least draggy rocket might not be one with fins and NC glued to the motor, and added weight can sometimes increase altitude. I could run some sims to prove this, but I'll leave that as an exercise.

Click to expand...

Lol good point, I was just joking about sticking fins and a nose cone to a motor, but your right. There's simply too many factors. Also the would CG would be petty back unless you weight the nose cone. I already ran sims for my gimbaled and fin stabilized rockets, and there's just too many factors

RocketEnthusiast101 said:

Hi. After searching on google regarding this topic, I did find calculations regarding the altitude achieved by rockets but I couldn't find an exact link related to this topic. I do know that there are several factors influencing the altitude gained by the rockets. But, I just want a rough idea or estimations from your experiences on what altitude each motor can deliver.

Click to expand...

Can you tell us about yourself and your experience and what you want to accomplish?

l may be beating a dead horse, yet I think I have a worthwhile clarification to add.

Rocket Enthusiast, you did have the sense to emphasize that you're only asking for an approximation. The basic problem is that not only are there other factors, as you said, but that those other factors grossly outweigh the motor choice, making any blanket statement, even an approximate one, impossible.

A better way to ask what perhaps you're looking for would be this: Given a reasonably "normal" rocket design for 18m and 24 mm BP motors, - weight size, and shape within some sort of typical range - approximately what altitudes can you expect. Even at that, you probably can't do netter that plus or minus 50%. And the information is available on the face cards of kits.

For larger rockets and other motors, as others have said you'll need to run simulations using any of the tools folks have mentioned above.

Yukon@K-9 Rocket Tech said:

Easiest way to achieve the highest altitude possible with a a rocket motor is to epoxy some fins and a nose cone right onto the motor. Boom, nothing will go higher than that with that motor.

Click to expand...

Good idea, but check it is valid within the rules of the club you launch with. It would technically be a motor modification and thus excluded at some (most?) club launches, except research events.

Yukon@K-9 Rocket Tech said:

Easiest way to achieve the highest altitude possible with a a rocket motor is to epoxy some fins and a nose cone right onto the motor. Boom, nothing will go higher than that with that motor.

Click to expand...

Minimizing drag & minimizing mass == speed
Minimizing drag & optimizing mass == altitude

OverTheTop said:

Good idea, but check it is valid within the rules of the club you launch with. It would technically be a motor modification and thus excluded at some (most?) club launches, except research events.

Click to expand...

I don't think it's a good Idea at all, I was just joking. I think it will be super unsafe lol

Yukon@K-9 Rocket Tech said:

I think it will be super unsafe lol

Click to expand...

Probably not, if the structure added doesn't weaken the casing. It does become research though, and remember you don't need insurance till you need it. Then you really need it. Play within the rules in case something does go wrong.

Looks like you could get 11600' with an I-430 in a 3FNC config. There might be some challenges to do that and recover the device.

Yukon@K-9 Rocket Tech said:

Lol good point, I was just joking about sticking fins and a nose cone to a motor

Click to expand...

Though, we actually did that with Estes motors when I was a kid. Cardboard fins and a paper NC glued to the motor, and sometimes (cough) a payload in the NC which would probably be frowned upon by the safety guidelines. A fun, single-use rocket.