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Genesis of LMR & HPR.

Main Safety Code Page for consumer model rocketry and high power rocketry.


SAFETY AND STANDARDS
Refer to NAR Model Rocket Safety Code for MR and LMR.
Refer to NAR High Power Rocketry Safety Code for HPR.
Refer to RRI, PRS and RRS rules or
California state law for amateur rocketry.
Refer to NFPA-1122 rules for model rocketry guidelines.
Refer to NFPA-1127 rules for high power rocketry guidelines.



Motor Usage and Permits

Certifications are relevent only to internal club policies
and their members and sponsored launches.

Uncertified (by your club) commercially produced motors are safe and legal
and motors certified by a club other than yours are safe and legal
and can be operated by any adult with :

1. Landowner permission or legal exemption
2. Local Fire Department permission or permit (AHJ)
3.
FAA exempt under 453/113g (liftoff wt/propellant wt)
FAA notification under 1500/125g (liftoff wt/propellant wt)
FAA wavier otherwise.

Certifications performed by one club once recognized by another
club then apply to each equally.
Q: Regarding consumer sales
A: Any club can form to comply with 1122/1127.
Schools are or can be state owned. Under 1127 exemptions for
schools and industry. School or comercial PO needed.


Changing weight limits and legal treatments

Traditional model rockets under 1.0 pound
FAA exempt (Thank you Harry Stine)

Large model rockets under 3.3 pounds (Thank you Jerry Irvine)
NAR limit
FAA notification only (Thank you Harry Stine)

High power rockets no liftoff weight limits
FAA wavier required

Traditional model rockets under 113g propellant
obsolete limit (Thank you Jerry Irvine)

Large model rockets under 125g propellant (Thank you Jerry Irvine)
NAR limit
FAA limit

High power rockets over 125g propellant or over 80 newtons thrust (stupid rule)
FAA wavier required over 125g propellant
HPR rules except FAA wavier apply to MR over 80n average thrust (stupid rule)

"Stupid" rule came from a CPSC limit arbitrarily applied from their prior
rules up to 80ns was a "consumer motor". They agreed to allow up to 62.5g
motors as "consumer" motors as long as all MR motors were limited to 80n
average and age limits were applied to G motors of age 21. The whole thing
is a kludge and nonsense.


Simple access and operational rules:

Micro-10C motors, 14 or over to purchase and operate,
8 or over to operate with adult supervision

11D-124G motors, 18 or over to purchase and operate,
10 or over to operate with adult supervision

125G+, 21 or over to purchase and operate.
14 or over to operate with adult supervision


Motor Designations

NAR method
(F40-8)

F - Power range NAR definition (table)
40 - Average thrust Newtons (4.448 N per Lb)
8 - Coast time seconds (5% of peak thrust start, burnout, to ejection)


Major Technical Innovation

ILP method
(USR 29mm 80F40-8STD)

USR - Manufacturer designation
29mm - Diameter (18mm=0.69", 24mm=0.935", 29mm=1.125",
38mm=1.5", 54mm=2.125", 75mm=3")
80 - Power Newton-seconds (4.448 N-s per Lb-sec)
F - Power range NAR definition (table)
40 - Average thrust Newtons (4.448 N per Lb)
8 - Coast time seconds (5% of peak thrust start, burnout, to ejection)
STD - Propellant style or read

Also delays and other options have designations.
1-15 is delay time in seconds, P is plugged,
0 is a booster motor, X is a consumer modifiable
delay sometimes expressed as 12X to designate the
initial unmodified delay is 12 seconds.

ILP method allows accurate power determination from
previously vague and misleading motor codes. Example
FSI F100 (implication 80F100) was tested as 42E48.
A user knowing this could stage two of them in F
altitude competition and fly twice as high as the
competition. The USR founder personally proved this
when he flew an FSI E60-0 to FSI F100-10 in F altitude
competition at Harry Stine's NARWIN-1 competing against
FSI owner Lonnie Reese. The rocket went 1041 Meters, a
record by a wide margin.

Another example is the vernerable and popular Estes D12
(implication 20D12). It is actually a 16.2D11. Still a
truly great motor.

The practical benefit of ILP beyond fair disclosure of power
is that for the first time in rocket history one can determine
motor burning time from the motor code!! Power divided by
average thrust equals burning time. 80F100=0.80s, 42E48=0.88s
(fooling consumers for decades). 20D12=1.67s, 16.2D11=1.47s
(fooling consumers for decades). 24mm 120G280=0.43s (exciting
consumers for decades).


Government Designation Method

(1.8KS9.0-STD)

1.8 - Burning time (10% of peak method - action time)
KS - Propellant designator (KS=AP/HTPB)
9.0 - Average thrust (pounds)
STD - Propellant read (effects)

The benefit to this system is by knowing the thrust and time
the power can be calculated. By knowing the propellant type
the burning rate exponent or other physical or ballistic
properties can be estimated to determine if the propellant
is suitable for the task.


NAR power table
NAR
Letter
Type
Maximum
Newton-
Seconds
Maximum
Pound-
Seconds
micro0.31250.07
1/4A0.6250.14
1/2A1.250.28
A2.50.56
B5.01.12
C102.25
D204.5
E409
F8018
<=F adult=18 years, >F adult=21 years
G16036
H32072
under 125g FAA exempt
240H model rocket
over 125g HPR
I640144
J1280288
K2560576
L51201152
M102402300
N204804600
O409609200
<= O defined consumer HPR power
>O is amateur or commercial rockets
P82K18400
Q164K36800
R328K73600
S656K147200
T1312K294400
U2624K590K
V5248K1080K
W10.5M2160K
X21M4320K
Y42M8640K
Z84M17.28M
K=000 M=000000 T=000000000



USR safe distance guidelines
NAR
Letter
Type
Minimum
USR Safe
Distance
NAR
Specified
Distance
micro-B5 feet15 feet
C-E15 feet15 feet
F-H30 feet30 feet
I-K50 feet200 feet
L-N100 feet1000 feet
O+300 feet1500 feet
Be safe not silly. Offset distances protect from motor
failures or thrust output only. Excessive distances
prevent owner and spectators from seeing boost and
feeling the power.



USR safe STATIC TEST
distance guidelines
NAR
Letter
Type
Minimum
USR Safe
Static Test
Distance
Minimum
Baracaded
Static Test
Distance
micro-B5 feet1 foot
C-E10 feet1 foot
F-H20 feet2 feet
I-K40 feet3 feet
L-N50 feet10 feet
O+100 feet10 feet
Offset distances specific to static tests protect from
motor failures or thrust output. Unbarricaded assumes
the motor is in a fixed position stand nozzle up or
nozzle perpindicular to people who are to the side of
the motor and/or behind the nozzle side. The casing is
not steel. Barricaded distances assume there is a
multilayer wood wall or a wall with thick plexiglass
plate inset for viewing or photography. The primary
purpose for this guideline is for educational and
testing programs.



USR safe launch pad RADIUS guidelines
Combustable free for 10 feet radius
Very low combustable for 20 feet radius



USR launch site size guidelines
1/4 the expected altitude
1/8 the expected altitude with
proven dual deployment system
1/2 the expected altitude if
3 stage or cluster of 8 or more or
unproven aerodynamic design
1/4 the expected altitude rule has been
proven in over 4 decades of operations.


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