AA-2_Propellant_-_AS2544-U_Item_Spec.pdf

INCH-POUND

DTL AS 2544 U

CAGE Code 14083

15 February 2013

SUPERSEDING

AS 2544 T

31 October 2012

DETAIL SPECIFICATION

ITEM SPECIFICATION

FOR

PROPELLANT GRAIN, MARK 90 MOD 0

(FOR USE IN MOTOR, ROCKET, 2.75-INCH, MARK 66 MOD 4)

Prepared for:

Product Manager, Joint Attack Munition Systems

Redstone Arsenal, AL 35898-5610

Prepared by:

Naval Surface Warfare Center, Indian Head Division

Indian Head, MD 20640-5035

SUBMITTED BY:_______________________________ DATE:________

Michael Dutton

2.75-Inch Rocket Motor Design Agent

NSWC Indian Head Division

APPROVED FOR USE AS

PRODUCT BASELINE BY:_______________________________ DATE:________

Brian Goedert

PMA-242 Chief Engineer for Airborne Rockets

NSWC Indian Head Division

AMSC N/A FSC 1340

DISTRIBUTION STATEMENT D: DISTRIBUTION AUTHORIZED TO THE DEPARTMENT OF DEFENSE

AND DOD CONTRACTORS ONLY; ADMINISTRATIVE OR OPERATIONAL USE; 28 MAY 1996. OTHER

REQUESTS FOR THIS DOCUMENT SHALL BE REFERRED TO COMMANDER, NAVAL SURFACE

WARFARE CENTER, INDIAN HEAD DIVISION, INDIAN HEAD, MD 20640-5035.

DESTRUCTION NOTICE. FOR UNCLASSIFIED, LIMITED DOCUMENTS, DESTROY BY ANY METHOD

THAT WILL PREVENT DISCLOSURE OF CONTENTS OR RECONSTRUCTION OF THE DOCUMENT.

2/15/13

2/15/13

AS 2544U

1. SCOPE

1.1 Scope. This specification covers the requirements for the Mark 90 Mod 0 Propellant Grain (see 6.1).

2. APPLICABLE DOCUMENTS

2.1 General. The documents listed in this section are specified in sections 3, 4, or 5 of this specification. This section does not include documents cited in other sections of this specification or recommended for additional information or as examples. While every effort has been made to ensure the completeness of this list, document users are cautioned that they must meet all specified requirements documents cited in sections 3, 4, or 5 of this specification, whether or not they are listed.

2.2 Government documents.

2.2.1 Specifications, standards, and handbooks. The following specifications, standards, and handbooks form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract (see 6.2).

STANDARDS

MILITARY

MIL-STD-810 Environmental Test Methods and Engineering Guidelines

MIL-STD-1168 Ammunition Lot Numbering and Ammunition Data Card

(Copies of these documents are available online at https://assist.dla.mil.)

2.2.2 Other Government publications. The following other Government documents, drawings and publications form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract (see 6.2).

PUBLICATIONS

NAVY

IHSP 03-488 Qualification Program Plan for Ultrasonic Internal

Inspection of Propellant Grain Mark 90

IHSP 07-512 Qualification Program Plan for Real-time Radiography

Internal Inspection of Propellant Grain Mark 90

DRAWINGS

NAVY

233AS106 Mark 90 Mod 0 Propellant Grain

233AS803 Mark 66 Rocket Motor Thrust Adapter

233AS900 Motor, Rocket, 2.75 Inch, Mark 66 Mod 4

(Copies of Government documents, drawings and publications required by manufacturers in connection with specific acquisition functions should be obtained from the contracting activity or as directed by the contracting officer.)

2.3 Non-Government publications. The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the solicitation or contract (see 6.2).

AEROSPACE INDUSTRIES ASSOCIATION OF AMERICA, INC.

NAS 410 NAS Certification and Qualification of Nondestructive Test

Personnel

(Copies of this document are available online at http://www.techstreet.com/aiagate.html.)

AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM)

ASTM E 1001 Standard Practice for Detection and Evaluation of

Discontinuities by the Immersed Pulse-Echo Ultrasonic

Method Using Longitudinal Waves

ASTM E 1255 Standard Practice for Radioscopy

ASTM E 1742 Standard Practice for Radiographic Examination

(Copies of these documents are available online at www.astm.org.)

AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI)/AMERICAN SOCIETY FOR

QUALITY (ASQ)

ANSI/ASQ Z1.4 Sampling Procedures and Tables for Inspection by Attributes

(Copies of this document are available online at http://www.ansi.org.)

2.4 Order of precedence. Unless otherwise noted herein or in the contract, in the event of a conflict between the text of this document and the references cited herein (except for related specification sheets), the text of this document takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained.

3. REQUIREMENTS

3.1 First article. Unless otherwise specified (see 6.2), a first article sample shall be submitted for testing (see 4.3).

3.2 Conformance to documents. Unless otherwise specified, the propellant grain shall meet the requirements specified herein and in the Mark 90 Mod 0 Propellant Grain drawing package (see Drawing 233AS106) including all the subassembly drawings.

3.3 Materials and components. Unless otherwise specified, all materials and components shall conform to the requirements specified herein and in the Mark 90 Mod 0 Propellant Grain drawing package (see Drawing 233AS106) including all the subassembly drawings.

3.4 Ballistic requirements. The propellant grain, when static fired, shall meet the requirements of TABLE I (see 4.5.2).

3.5 Internal defects. The propellant grain shall be free of unacceptable internal defects in the critical web section (see 4.5.1).

3.6 Nondestructive testing (NDT) certification.

3.6.1 Nondestructive testing personnel. Personnel performing nondestructive tests and evaluations shall be certified in accordance with NAS 410. Level III NDT personnel must possess a current ASNT NDT Level III certification in the NDT method to be taught prior to certifying Level I/II personnel.

3.6.2 Nondestructive testing equipment/technique. The equipment and technique used to perform nondestructive tests shall be certified in accordance with IHSP 07-512 for real-time radiography inspection and IHSP 03-488 for ultrasonic inspection.

TABLE I

BALLISTIC PERFORMANCE REQUIREMENTS

PARAMTER

FIRING TEMPERATURE

50 F

150 F

Lower

Upper

Lower

Upper

Action time (sec) Impulse (lbf-sec) Maximum thrust (lbf) Time </= 0.5 sec Time> 0.5 to </= 0.7 sec Time > 0.7 sec

1.00

1.21

0.90

1.10

4. VERIFICATION

4.1 Classification of inspections. The inspection requirements specified herein are classified as follows:

a. First article inspection (see 4.3)

b. Quality conformance inspection (see 4.4).

4.2 Inspection conditions. Unless otherwise specified (see 6.2), all inspections shall be performed as specified in the applicable test method of 4.5.

4.3 First article inspection. First article inspection shall be performed after award of contract and prior to production by a facility designated in the contract or order (see 6.2). First article inspection shall be performed on sample units which have been produced using the same materials, equipment, processes and procedures as will be used in regular production. All parts and materials, including packaging and packing, shall be the same as used for regular production and shall be from the intended sources of supply.

4.3.1 Sample size. The first article sample shall consist of 500 propellant grains.

4.3.2 Verification routine. The entire first article sample shall undergo the inspections specified in 4.5.1. 40 propellant grains from the first article sample shall undergo the inspection specified in 4.5.3, and then be loaded and subjected to the temperature shock test in accordance with

MIL-STD-810 (see section 6.6 for revision and method) except that the low temperature shall be

-65 ºF ± 5 ºF (-54 ºC ± 3 ºC) and the high temperature shall be +150 ºF ± 5 ºF (+66 ºC ± 3 ºC).

The duration at each temperature shall be a minimum of 8 hours and no longer than 12 hours.

The transfer time between test temperatures shall be no greater than five minutes. A total of 3 ½ cycles shall be completed for this test with one cycle being defined as exposure of the test item to the low temperature followed by exposure of the test item to the high temperature.

After completion of the temperature shock test, the 40 rocket motors shall be static fired in accordance with 4.5.2, with half of the rocket motors fired at -50 ºF and half of the rocket motors fired at +150 ºF. All 40 rocket motors shall meet the acceptance criteria of 4.5.2.3.a and 4.5.2.3.c thru 4.5.2.3.e. In addition, the average action time and average impulse value of each firing temperature shall fall within the limits of Table I.

Also 60 propellant grains from the first article sample shall be loaded and static fired in accordance with 4.5.2, with half of the rocket motors fired at -50 ºF and half of the rocket motors fired at +150 ºF. All 60 rocket motors shall meet the acceptance criteria of 4.5.2.3.a thru

4.5.2.3.e.

4.3.3 Failure. Failure of the sample to meet the requirements of this specification shall be cause for rejection of the first article sample.

4.4 Quality conformance inspection. Quality conformance inspection shall consist of attribute inspection, internal inspection, and ballistic performance testing. The test and inspection methods and acceptance criteria are specified in 4.5.

4.4.1 Lot size. Unless otherwise specified (see 6.2), the production lot size for the first five production lots shall consist of 10,000 items or less, and thereafter shall be 1,000 minimum and

22,000 maximum (exclusive of those required for destructive tests). A lot shall consist of material from a single production line with homogeneous manufacturing techniques. Each propellant grain lot shall be made from no more than two lots of propellant sheetstock. The term

"lot", as referred to in this document, shall mean production lot. Lots shall conform to the requirements found in MIL-STD-1168.

4.4.2 Sampling.

4.4.2.1 Attribute inspection. Sampling for attributes listed on applicable drawings shall be in accordance with ANSI/ASQ Z1.4, General Inspection Level II, Single Sampling Plan. Critical characteristics shall be inspected 100 percent with no defects allowed.

4.4.2.2 Ballistic performance testing. Sampling for ballistic performance testing shall be made after lot acceptance for attribute inspection.

4.4.2.2.1 Sample size. Sample size shall be based on TABLE II. Samples shall be selected independently for each conditioning temperature (50 F and 150 F). The ballistic performance test sample shall contain a quantity of rewrapped grains that is proportionate to the total number of rewrapped grains in the lot. The test sample that contains the rewrapped grains shall be evenly divided as much as possible between the two temperature conditions.

4.4.2.2.2 Spares. Up to ten grains shall be randomly selected as spares in addition to those selected in accordance with 4.4.2.2.1. Unused spares may be returned to the lot.

4.4.2.2.3 Criteria for severity of inspection. Severity of inspection shall be determined independently for each conditioning temperature. In the event of a major change in production equipment or source of component parts, or of a serious or prolonged interruption in production, tightened inspection shall be used on the next 10 lots submitted. If a maximum thrust failure occurs at time > 0.7 second when a reduced inspection is being used, the sample size for the next GLAT will remain reduced. If the grain lot is rejected while on reduced inspection for failing any other ballistic acceptance criteria noted in 4.5.2.3, tightened inspection shall be used on the next 10 lots submitted. Reduced inspection shall be reinstated after the preceding 10 lots have been on tightened inspection and none has failed with the exception of maximum thrust failure at time > 0.7 seconds. The sample sizes required for tightened or reduced inspection are defined in

TABLE II.

TABLE II

SAMPLE SIZE REQUIREMENTS

Tightened sample size

Reduced sample size

Statically fired at 150 F

Statically fired at 50 F 52 20

4.5 Test and inspection methods.

4.5.1 Internal inspection. Each billet or finished grain shall be real-time radiographically or ultrasonically examined over its entire length to verify that it does not contain an unacceptable internal defect in the critical web section. Any billet or finished grain that is found to contain an unacceptable internal defect (see 4.5.1.3), when ultrasonically examined, shall be either rejected or real-time radiographically examined. If no unacceptable internal defects are then found during real-time radiography examination, then the billet or finished grain is to be accepted;

otherwise; if any unacceptable internal defect is found, the billet or finished grain is to be rejected.

4.5.1.1 Internal inspection methods.

4.5.1.1.1 Real-time Radiography. The billets or finished grains shall be examined while rotating about their longitudinal axis such that a minimum of 360 degrees shall be rotated through while a given point is in the field of view. Rotational and axial translation speed shall be controlled so that the required 2-1T sensitivity can be displayed in motion. The real-time radiography technique shall comply with the requirements of ASTM E 1255, Annex “A” and ASTM E 1742 and shall be identical to the technique used to pass the qualification test detailed in IHSP 07-512, the Real-time Radiography Inspection Qualification Program Plan for the Internal Inspection of the Mk 90 Propellant Grain. After successful completion of the qualification demonstration, the Contracting Officer will issue certification for this inspection. This certification is required prior to implementation of real-time radiography inspection. Real-time radiography examination shall be conducted with two independent technicians reviewing each billet or finished grain. The first of these two required reviews shall be made during the live x-ray of the billet or finished grain.

The second review shall be made from the video record. As a minimum, one of the two reviews shall be made by either a certified Level II or Level III NDT individual.

4.5.1.1.2 Ultrasonic. The billets or finished grains shall be evaluated using the pulse-echo and through-transmission methods. The billets or finished grains shall be scanned either in a helix pattern along the longitudinal axis or by scanning circumferentially and stepping along the longitudinal axis. The rotational and axial scanning speeds shall be controlled so that the applicable reference reflector(s), as defined in IHSP 03-488, can be consistently detected and sized. The ultrasonic technique shall comply with the requirements of ASTM E 1001 and shall be identical to the technique used to pass the qualification test detailed in IHSP 03-488, the Ultrasonic Inspection Qualification Program Plan for the Internal Inspection of the MK 90 Propellant Grain. After successful completion of the qualification demonstration, the Contracting Officer will issue certification for this inspection. This certification is required prior to implementation of ultrasonic inspection. All billets or finished grains will receive two independent ultrasonic evaluations. One evaluation shall be by either a certified Level II or Level III NDT individual. The other evaluation shall be by a certified Level I, Level II, or Level III NDT individual or certified automatic internal defect recognition system.

4.5.1.2 Definition of internal defects.

a. Fissure A linear discontinuity with a large axial and circumferential component and a minimal radial component. Separate but lineal fissures separated by 0.25 inch or less shall be considered a single continuous fissure. A fissure is most readily detected during real-time radiography (RTR) inspection when it appears to be at its maximum radial distance from the bore. It will appear at that time to be a long thin relatively bright white line. When rotated away from the maximum radial location the indication gets wider and less bright.

b. Poor consolidation Signs of swirly propellant discontinuities, or spider lines or spider lines with bursts. Spider lines generally have a large axial and radial component with a minimal circumferential component. Radiographically, spider lines have the highest density contrast when seen near the bore. Spider lines however can be detected in the web or the bore. When rotated, spider line indications appear relatively thin and bright near the bore and appear to get wider and less bright in the web. A special case of spider lines, spider lines with bursts, appear on RTR as long thin lines with wider light anomalies along its length. Rotating the grain does little to affect the indications appearance.

c. Void Any area within the grain where porosity or absence of propellant is detected.

Any region of porosity is to be considered in total as a single void.

d. Crack A form of propagating fracture type characterized by sharp tip and high ratio of length and width to opening displacement. Cracks in grains propagate from the inside, outside or end surface. When detected with RTR, a crack appears as a light line (when using a positive image) starting at a surface and propagating into the grain.

Depending upon the crack’s orientation, it will have a large axial and radial component with a minimal circumferential (thickness) component and be easy to detect near the bore or it will have a large circumferential and radial component with a minimal axial (thickness) component and be easy to detect in the web. Rotating the grain will normally cause the crack’s image to appear and disappear or seem to travel.

e. Foreign material Undissolved propellant constituents or material inclusion appearing as an area of high density within the grain. Any foreign material separated by 0.25 inch or less shall be considered a single continuous piece of foreign material.

f. Press Indication A visual indication in the bore of the grain. A press indication is usually found 6 to 10 in into the first grain after the press neck. The press indication is characterized by a slight circumferential protrusion of propellant into the grain bore.

A press indication is not considered a defect whether inspected visually, radiographically, or ultrasonically.

g. Press Ring A visual indication usually found 6 to 10 in into the first grain after the press neck. A press ring is characterized by a slight circumferential protrusion of propellant into the grain bore along with a series of internal voids in the same plane as the protrusion. A press ring is easily detected radiographically. A press ring is not considered a defect whether inspected visually, radiographically, or ultrasonically as long as the voids do not extend into the critical web.

h. Stealth A stealth defect is considered to be a severe form of a press ring. A stealth defect is characterized by a series of internal discontinuities that initiate in the grain bore, each with a major radial and minor longitudinal component distributed in the same circumferential plane. Normally the stealth defect is also associated with a pattern of multiple tearing of the flutes.

4.5.1.3 Description of internal defects considered unacceptable.

a. A single fissure or void with any dimension that exceeds 0.085 inches.

b. Two or more fissures or voids that are present in the same radial plane. A radial plane is defined as any plane that is perpendicular to the longitudinal axis of the grain.

c. Any signs of poor consolidation.

d. A single instance of foreign material with any dimension exceeding 0.125 inch radially or 0.5 inch longitudinally.

e. A crack.

f. A stealth defect.

4.5.1.4 Description of internal anomalies considered acceptable when detected during either real-time radiography or ultrasonic examination.

a. Chipped area, unbonded area or void that extends to or appears at the boundary between the propellant and the peripheral inhibitor or between the propellant and end inhibitors.

b. Foreign material that appears at the boundary between the propellant and the peripheral inhibitor or between the propellant and end inhibitors or between layers of the peripheral inhibitor.

c. Chipped area in any of the eight grain tips at either end of the billet or at the forward end of the finished grain as long as no portion of the chipped area extends into the critical web section more than 0.085 inches.

4.5.2 Ballistic Performance Testing. The grains selected for static-firing tests shall be tested with the approved equipment and according to the approved procedures. Grains shall be loaded into the test rocket motor conforming to Drawing 233AS900 (retouching the motor tube painted surfaces, applying the rocket motor stencils, and application of the brown band are optional – any additional painted or stenciled external markings are acceptable). A direct current (dc) power supply shall provide a firing current of 1.5 0.15 amperes to the ignition circuit of the test motor. After the static-firing tests, an inspection of the rocket motor hardware shall be made to ensure the acceptance criteria of 4.5.2.3 are met.

4.5.2.1 Test Equipment.

(A) Test Stand:

(1) Component Functions: The test stand shall hold the rocket motor on a horizontal plane, aligning the motor with the thrust cell. It will allow the motor to slide horizontally with minimal friction during firing, prevent rotational movement, and will not induce harmonic oscillations that affect the measurements. The stand shall allow recovery of components that are ejected or dispersed during catastrophic failure, and will not restrict expansion or bulging of the motor tube during firing.

(B) Thrust Adapter:

(1) Component Function: The thrust adapter translates the thrust from the motor tube to the thrust cell.

(2) Spec: For grain lot acceptance tests, use NAVAIR drawing 233AS803. Alternate equipment may be utilized if approved by the procuring activity.

(C) Flexures (Optional):

(1) Component Function: Translate thrust and disallow any side loading which would cause a false thrust reading.

(2) Spec: Two flexures, one ahead of the thrust cell and one behind the thrust cell, shall be used.

(D) Transducer:

(1) Component Function: Transducers are electronic devices that translate static or dynamic changes in force into changes in voltage. This change in voltage produces, in the readout instrumentation, a repeatable deflection or indication that can be calibrated directly in terms of the force applied to the transducer.

(2) Spec: One load cell transducer is required to measure rocket motor thrust. This transducer shall have dual isolated strain gage bridges producing two channels of data. Standard commercial strain gage type thrust transducers shall meet the following specifications.

a. Thrust Transducer

1. Force Measurement Range: 4000 to 5000 lbf

2. Insulation Resistance of wires to ground: Greater than 5000 megohms

3. Compensated Temperature Range: -15 to +115 F

4. Calibration Accuracy: Within 0.10% of F.S.

5. Nonlinearity: Less than 0.05% of F.S.

6. Repeatability: Within 0.02% of F.S.

7. Hysteresis: Less than 0.02% of F.S.

8. Temperature Effect on Output: 0.0008% of F.S. per F

9. Temperature Effect on Zero Balance: 0.0015% of F.S. per F

10. Natural Frequency: Greater than 2,200 HZ

(3) Full Scale (F.S.) used above means the maximum force applied, in this case equivalent to the selected range, at which the output signal remains within the above requirements. The transducer shall function to 150% of the full scale and not fail as a result of this overrange. The transducer F.S. values specified are well above normal thrust values to handle motor failures and to help increase the frequency of harmonic oscillations and to help determine failure related events.

(E) Lines/Wiring Method:

(1) Component Function: The wiring technique provides for double shunt resistor calibration of a full bridge strain gage transducer. The method shunts precision fixed value resistors simultaneously across opposing legs of the bridge. The exact millivolt differences in the output signal must correspond exactly to calibration values for a minimum of two steps, 1/2 and full scale.

The resistors use the extra four wires to drop the resistance of opposing legs.

(2) Spec: The wiring method shall provide for an eight wire double shunt resistor calibration of a full bridge strain gage transducer.

(F) Calibration:

(1) Component Function: The calibration before a test entails calibration of the thrust transducers.

(2) Spec: Double Shunt (opposing legs) calibration shall be done and recorded prior to every firing. The calibration before each test entails shunting calibrated National Institute of Science and Technology (NIST) precision resistors across the wheatstone bridge to simulate known thrust levels. A calibrated millivolt meter is allowed in lieu of the precision resistor. Both the meter and resistor calibration shall show traceability to NIST. Transducer calibration shall be done at least every 6 months according to the NIST and show traceability to NIST standards.

(G) Signal Conditioner:

(1) Component Function: The signal conditioner is used to calibrate the system electronically.

For system calibration, the operator induces a calculated change in gage impedance to produce a full scale voltage output that corresponds to the full scale thrust. Other calibration resistors are used to produce ¼, ½ and ¾ step voltages to check system linearity. Verification of the electronic calibration is through the use of a dead weight tester or use of a standard calibration device which has precision voltage output. This shall be done annually or whenever a question about accuracy arises.

(2) Spec: Commercial units are available that will adequately perform the task. Signal conditioners shall provide excitation voltage, bridge (zero) balance, and 4 step double shunt calibration. An 8 wire transducer interface shall be used, 4 wires for calibration and 4 wires for excitation and signal. All units shall meet the following specifications.

(1) Excitation Voltage: 2-15 Volts DC

(2) Regulation (Line): 0-0.01% (Load): 0-0.01%

(3) Ripple: Less than 100 microvolts peak-peak

(4) Resolution: Less than 2 millivolts

(5) Isolation: Greater than 10,000 Megohms

(6) Temperature Coeff: 0.005% of F.S. per F

(7) Low pass frequency response: Greater than 50 KHz

(3) There are several design considerations that aid in the setup and accuracy of the overall system. These include:

(A) Proper grounding techniques and shielded cables.

(B) Isolating millivolt low level signals from high level/alternating current signals and power lines.

(C) Use of linear power supplies.

(D) A removable calibration resistor card with precision fixed value resistors.

(H) Amplifier:

(1) Component Function: A solid state, DC instrumentation amplifier which amplifies a small signal in the millivolt range to the volt range.

(2) Spec: A standard commercial unit is suggested with the following minimum requirements:

(1) Gain step accuracy: 0.1% minimum

(2) Gain temperature Coeff: 0.005% FS/ F

(3) Gain stability: 0.005% FS/ F at constant temperature

(4) Linearity: 0.005% FS

(5) Bandwidth (3DB Point): DC to 100 KHz

(6) Noise Full Bandwidth: 6 microvolts reference to input +6 millivolts reference to output

(7) Settling Time: 30 microsec to within 0.1%

(3) There are several design considerations that are not technical specification but aid in the setup and accuracy of the overall system. These include:

(A) A provision for vernier gain control between gain steps.

(B) A high input impedance (greater than 10 megohms).

(C) Dual outputs (one filtered and one unfiltered).

(D) Low output impedance with high slew rate.

(E) Shorting switch, with input and output zero potentiometers.

(I) Sample Rate:

(1) Component Function: The sample rate is the number of times per second that the digitizer converts an analog signal voltage to a digital number.

(2) Spec: 2000 Samples per second minimum

(J) Filter:

(1) Component Function: The filter is primarily used to eliminate the effects of aliasing in the digital data. Characteristics of the filters are significant such as passband linearity, impulse response, phase shift, and rolloff rate.

(2) Ideal Setup: The filter shall be a 100 Hz analog filter (Bessel, Butterworth, Eclipitic, Time Delay) that meets the following specifications:

(A) Passband ripple should be less than 0.1 DB peak to peak maximum.

(B) 12 DB/octave rolloff 2 pole minimum.

(C) Linear phase shift to less than 0.05% and phase shift to less than 10% (36 degrees).

No greater than 2 msec delay.

(D) Impulse response produces less than 3% overshoot or dip.

(K) Digitizer:

(1) Component Function: The digitizer converts the analog input voltage, after filtering, to a digital representation whose accuracy depends on the number of bits in the conversion.

(2) Spec: The setup will use at least a 10 bit digitizer.

(L) Computer/Storage:

(1) Component Function: The computer is used to store the number that the digitizer generates corresponding to the value of the analog signal voltage. In other words, the computer stores the digital data. The computer also is used to calculate/record the ballistic parameters of the rocket motor firing.

(2) Spec: The computer shall be interfaced to the digitizer and at a minimum be able to receive the data from calibration and tests, store the data in non volatile memory, locate the maximum thrust and its corresponding time, and determine the firing time. The computer shall be reliable and not experience errors repeatedly.

(A) Software: The software shall adequately capture and process the required data. The software shall operate the computer in a glitch free fashion. Lock-up, errors, loss of data, or other problems shall not occur on a repeated basis.

(B) System Configuration: The system consisting primarily of transducers, signal conditioners, amplifiers, filters, digitizer, connectors, wiring and enclosures shall be configured as no less than a 3 channel system. For grain lot acceptance tests, two channels shall record thrust and one shall record firing current. Standard instrumentation practices shall be utilized to assure that noise, glitches, cross talk or other factors do not interfere with the data integrity. The overall system shall exhibit an accuracy within 0.25% F.S. Channel to channel phase shift shall be less than 0.1 milliseconds. Multiple components from various commercial vendors are available as well as fully integrated system in a single enclosure, that will perform adequately.

(C) Printer: The printer shall be interfaced to the computer and shall be capable of producing data plots as well as numeric tabular data lists in a quick and clear fashion.

4.5.2.2 Temperature conditioning. Grains selected in accordance with 4.5.2 shall be conditioned to ensure a uniform temperature throughout the grain at the time of firing. The minimum conditioning time shall be 8 hours; the maximum total cumulative conditioning time shall be 48 hours. Any grain that is conditioned more than 48 hours shall be returned to the grain lot and another grain shall be fired in its place. During the last 3 hours of conditioning, the oven temperature shall be maintained within 3 F of the specified temperature. Test motors not fired between 3 and 3.5 minutes after removal from conditioning oven shall be returned for 1 hour for each additional 5-minute period over 3.5 minutes. Test motors left out of the oven over 50 minutes shall be reconditioned a minimum of 8 hours.

4.5.2.3 Grain lot ballistic performance testing acceptance criteria. A grain lot shall be accepted if the grains selected in 4.4.2.2 fulfill the following:

a. No grain shall have been the cause of a test motor failure (see 6.3) or blowup when fired at a temperature of 50 F or 150 F.

b. The test motor firings shall have met all of the requirements of 3.4. Unless AQLs are authorized by the Contract, the acceptance criteria shall be to accept the lot on zero defects and reject the lot on one or more defects. If AQLs are authorized by the

Contract, acceptance criteria shall be as follows: the contractor shall apply an AQL of

1% separately to the characteristics noted as Action Time and Impulse. The contractor shall apply the acceptance criterion of ASQ Z1.9. Table B-4 of ASQ Z1.9 applies for a sample size of 20. For sample sizes other than 20, the contractor shall use the

Maximum Allowable Percent Nonconforming (M) values and the Lot Percent

Nonconforming values shown in Table III below. When performing a retest, the contractor shall consider all samples tested when calculating the associated Quality

Index value. For Maximum Thrust testing, the acceptance criteria for time </= 0.5 sec and for time > 0.5 sec but </= 0.7 sec shall be accept on zero. For Maximum Thrust time >0.7 sec, paragraph 4.5.3.2 shall apply as written.

TABLE III

MAXIMUM ALLOWABLE PERCENT NONCONFORMING (M) VALUES

INSPECTION LEVEL SAMPLE

SIZE

LOT PERCENT NONCONFORMING

(PU or PL)

M VALUE

Reduced 38 Use Table B-5 of ASQ Z1.9, sample size 35 3.63

Reduced 52 Use Table B-5 of ASQ Z1.9, sample size 50 3.39

Tightened 52 Use Table B-5 of ASQ Z1.9, sample size 50 2.48*

* If an incipient failure or motor blow resulted in tightened inspection being used on the next 10 lots submitted, an M value of 1.73 shall be used.

c. No grain has caused incipient failure (see 6.3).

d. Paint discoloration/blistering is allowed on the forward 6 inches of the motor tube when the grains are fired at 50 F, and on the aft 1 inch of the motor tube when the grains are fired at 150 F. No heat induced discoloration or blistering of the paint all the way down to the gold colored chromate protective finish is allowed on any other portion of the motor tube during the static firings.

e. No nozzle rotation over 1/2 inch coupled with a maximum thrust value greater than

2600 lbf shall have occurred during any static firing.

f. If at 50 F one or more maximum thrust failures occur at times > 0.7 second, the following applies :

If the tightened sample size of 52 grains is being used, up to two failures are allowed; three or more failures reject the grain lot.

If the reduced sample size of 20 grains is being used and one or two failures occur, the grain lot will be considered acceptable provided one of the following

“retest” conditions occurs:

18 additional grains are static fired at the same conditioning temperature and all 38 grains meet the requirements of 4.5.2.3 with the exception of one maximum thrust failure at time > 0.7 second.

32 additional grains are static fired at the same conditioning temperature and all 52 grains meet the requirements of 4.5.2.3 with the exception of two maximum thrust failures at time > 0.7 second.

If the reduced sample size of 20 grains is being used and three or more failures occur, the grain lot will be rejected.

g. If at 150 F one or more maximum thrust failures occur at times > 0.7 second, the following applies:

If the tightened sample size of 52 grains is being used, one failure is allowed, provided no more than one other maximum thrust value exceeds 2600 lbf. Two failures are allowed, provided no other maximum thrust value exceeds 2600 lbf.

Three or more failures reject the grain lot. A single failure that exceeds 3300 lbf rejects the grain lot.

If the reduced sample size of 20 grains is being used and one failure occurs, the grain lot will be considered acceptable provided the following “retest” condition occurs:

18 additional grains are static fired at the same conditioning temperature and all 38 grains meet the requirements of 4.5.2.3 and do not have maximum thrust values that exceed 2600 lbf (with the exception of the one maximum thrust failure at time > 0.7 second). Also none of the 38 grains shall have a maximum thrust value that exceed 3300 lbf.

If the reduced sample size of 20 grains is being used and two failures occur, the grain lot will be considered acceptable provided the following “retest” condition occurs:

32 additional grains are static fired at the same conditioning temperature and all 52 grains meet the requirements of 4.5.2.3 and do not have maximum thrust values that exceed 2600 lbf (with the exception of the two maximum thrust failures at time > 0.7 second). Also none of the 52 grains shall have a maximum thrust value that exceed 3300 lbf.

If the reduced sample size of 20 grains is being used and three or more failures occur, the grain lot will be rejected.

4.5.2.4 Incident review. Any abnormal incidents, such as those outlined in 4.5.2.3, shall be cause for review by the procuring activity.

4.5.3 Attribute Inspection. Grains selected for attribute inspection shall be inspected in accordance with approved AIE, as required by the contract. Unless AQLs are authorized by the

Contract, the acceptance criteria shall be to accept the lot on zero defects and reject the lot on one or more defects. If AQLs are authorized by the Contract, acceptance criteria shall be as follows: an AQL of 1.0 percent shall be applied to each major characteristic as specified on the applicable drawing and an AQL of 4.0 percent shall be applied to each minor characteristic.

Critical characteristics shall be inspected 100 percent and any defectives shall be removed from the lot.

5. PACKAGING

5.1 Packaging. For acquisition purposes, the packaging requirements shall be as specified in the contract or order (see 6.2). When actual packaging of material is to be performed by DoD personnel, these personnel need to contact the responsible packaging activity to ascertain requisite packaging requirements. Packaging requirements are maintained by the Inventory

Control Points packaging activity within the Military Department or Defense Agency, or within the Military Department's System Command. Packaging data retrieval is available from the managing Military Department's or Agency's automated packaging files, CD-ROM products, or by contacting the responsible packaging activity.

6. NOTES

(This section contains information of a general or explanatory nature that may be helpful but is not mandatory.)

6.1 Intended use. The propellant grain described herein is intended for use in the Mark 66 Mod 4

2.75-Inch Rocket Motor. The propellant grain was designed specifically for military use and has no commercial application.

6.2 Acquisition requirements. Acquisition documents should specify the following:

a. Title, number and date of this specification or the title, revision and date of the

ADL233AS900.

b. Whether first article inspection is required, and if so, specify the test activity.

c. Production lot size if other than as specified (see 4.4.1).

d. Report of test results.

e. Packing and marking requirements.

f. That the safety precaution requirements of the "Contractor's Safety Manual for

Ammunition, Explosives, and Related Dangerous Material," DoD 4145.26M are applicable. NOTE: When this specification is used as part of the description of work to be accomplished by a Government activity, the safety precaution requirements of

"Ammunition and Explosives Ashore," OP 5 are applicable.

g. Test Activity.

h. Applicable AQL’s for attribute inspection and ballistic performance testing.

i. Records retention.

6.3 Definitions.

6.3.1 Maximum thrusts. The maximum thrusts are the highest thrust, recorded to the nearest lbf as scaled from the thrust-time curve, or as determined from the digital printout.

6.3.2 Motor failure. Motor failure is any failure of the motor tube or nozzle such as a high pressure blowup, burnthrough, or a fracture that is attributable to failure of the propellant grain.

6.3.3 Critical web section. The critical web section is as shown on Sheet 3 of Drawing

233AS106 as web thickness with the following exception: for a billet the critical web section only extends to within 1/8 inch of the outer diameter of the billet and for a finished grain the critical web section only extends to within 1/8 inch of the boundary between the peripheral inhibitor and propellant.

6.3.4 Action time. Action time is that length of time on the thrust-time curve that the motor thrust is continuously in excess of 150 pounds force.

6.3.5 Impulse. Impulse is the integral of thrust over action time.

6.3.6 Incipient failure. An incipient failure is any loaded motor static firing that results in 0.030-inch high or greater bulge in the side of the motor tube.

6.4. Packaging. The following packaging, packing and marking methods have been used successfully in the past and should be considered when writing the contract or purchase order.

Any deviation from the methods given herein should be verified by extensive safety testing and documentation.

6.4.1 Preservation and packaging. Unless otherwise specified, the propellant grains should be packaged in a container conforming to Drawing 233AS171.

6.4.2 Packing. The grains packaged in accordance with 5.1 should be packed in Pallet Crate Mk

2 Mod 0 conforming to LD288346 and MIL-STD-1322/53. Only grains from a single production lot should be packed in any box or crate. Alternate packing methods may be supplied by

NAVAIRSYSCOM.

6.4.3 Marking. In addition to any special marking required by the contract or order, shipping containers should be marked in accordance with MIL-STD-129, Drawing 233AS171, and

MIL-STD-1322/53.

6.5 MIL-STD-810 Revision and Method. Table IV details the MIL-STD-810 revision and it’s associated method for each requirement:

TABLE IV

MIL-STD-810 REVISIONS AND METHODS

REQUIREMENT MIL-STD-810

REVISION

METHOD

4.3.2 Temperature Shock Test F 503.4, Procedure 1

6.6 Changes from previous issue. Symbols are not used in this revision to identify changes with respect to the previous issue, due to the extensiveness of the changes. This revision incorporates

ECP R13R4350F.