D. IMPORTANT FACTS ABOUT ESTES MODEL ROCKET ENGINES
Due to their design as precisely manufactured packages of power with strictly
engineered tolerances, Estes engines are the standard in the industry. Some
important features are:
- A totally safe product throughout its 40+ year history, owing this outstanding record to experienced craftsmanship and engineering.
- Pre-manufactured propellants that are placed in their casings at the factory. The modeler does not have to handle or mix propellants, just insert the igniter in the engine and install the engine in the rocket.
- Expendable engines that are used once, then discarded. Attempting to reload these engines can be dangerous and is forbidden by regulations.
Manufacturing of or tampering with propellants can be extremely dangerous and is against the model rocket safety code. Expendable model rocket engines have provided the
foundation for model rocketry as an educational tool and hobby activity.
- Three percent of all Estes engines are tested for reliability and adherence to performance standards. If standards are not met, the engines do not make it to market.
The following illustrations help you picture the details of our engine.
Figure 6 illustrates the Estes color coding for use identification and the
alphanumeric code for performance ratings. Recommended launch field sizes
are shown in Figure 7 based on engine power usage.
ESTES ENGINE CODING
Estes engines are color-coded for recommended use. GREEN engines are for
use in single stage models; PURPLE engines for the top stages of multi-stage
rockets and very light single stage rockets; RED engines for all booster and
intermediate states of multi-stage models. YELLOW are “plugged” and
recommended for special uses only.
LAUNCH SITE DIMENSIONS
Installed Total Impulse
|
Equivalent Engine Type
|
Minimum Site Dimension
|
(Newton-Seconds)
|
|
(feet)
|
(meters)
|
0.00-- 1.25
|
1/4A & 1/2A
|
50
|
15
|
1.26-- 2.50
|
A
|
100
|
30
|
2.51-- 5.00
|
B
|
200
|
60
|
5.01-- 10.00
|
C
|
400
|
120
|
10.01-- 20.00
|
D
|
500
|
150
|
20.01-- 40.00
|
E
|
1000
|
300
|
40.01-- 80.00
|
F
|
1000
|
300
|
80.01-- 160.00
|
G
|
1000
|
300
|
160.01-- 320.00
|
2Gs
|
1500
|
450
|
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TYPICAL TIME/THRUST CURVES
ESTES B6-4 MODEL ROCKET ENGINE
|
Figure 8 shows a cross section of a standard Estes rocket engine and a time
thrust curve used to plot the engine’s performance. Comparing the force it
exerts (vertical axis) versus the time over which it burns (horizontal axis)
provided information about the engine’s total impulse, average thrust and
time delay.
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MODEL ROCKET ENGINE FUNCTIONS
Graphic explanation of a rocket engine’s
fundamental construction and functions.
|
|
Figure 9 shows the internal structure of a typical model rocket engine and the function of each component during a typical flight.
NOTE: Use the engine selection chart in the Estes catalog to determine your rocket’s engine requirements and flight profiles.
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WHERE TO FIND ESTES PRODUCTS:
The Estes materials that have been described above are available:
- Through your local Estes retailer including Estes Educator™ Authorized Retailers
- From school suppliers or wholesalers
- Direct from Estes Industries
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