7_Attachment 24 - NSWCCD-23-TM-2009-64 RevC Small Craft Transportability Design and Certification Process Guidance.pdf

Naval Surface Warfare Center Carderock Division West Bethesda, MD 20817-5700

NSWCCD-23-TM-2009/64 Rev C November 2009

Ship Systems Integration and Design Department

Technical Memorandum

SMALL CRAFT TRANSPORTABILITY DESIGN AND

CERTIFICATION PROCESS GUIDANCE

by

Michael Rugnetta Combatant Craft Division (23)

DISTRIBUTION STATEMENT A. Approved for public release;

distribution is unlimited.

N S

W C

C D

-2

-T M

-2

/6 R e v

C

S m a ll C ra ft

T ra n s p o rt a b ili ty

D e s ig n a n d

C e rt if ic a ti o n P ro c e s s G u id a n c e

SMALL CRAFT TRANSPORTABILITY DESIGN AND

CERTIFICATION PROCESS GUIDANCE

NSWCCD-23-TM-2009/64 Rev C

Post-Release Revisions

Revision Reviewer/ Approver

Date Change Description

Page, Section

A MJR/Code 3830 Nov. 25, 2009 Approved for Public Release cover, i

B MJR/MRR Code

Nov. 8, 2010 Editorial revisions Numerous

C NRL Code 231 Aug 16, 2012

Maritime transport loads, fastener specification, and editorial changes

7, 14, 16, 29, 32, 33, A-6

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24-11-2009

2. REPORT TYPE

Technical Memorandum

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Nov 2009 to Nov 2010

4. TITLE AND SUBTITLE

Small Craft Transportability Design and Certification Process

Guidance

5a. CONTRACT NUMBER

5b. GRANT NUMBER

5c. PROGRAM ELEMENT NUMBER

6. AUTHOR(S)

Rugnetta, Michael J.

5d. PROJECT NUMBER

5e. TASK NUMBER

5f. WORK UNIT NUMBER

7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) AND ADDRESS(ES)

NAVSEA Carderock

Surface Warfare Center Division

Combatant Craft Division

2600 Tarawa Court, Suite 303

Virginia Beach, Virginia 23459-3239

8. PERFORMING ORGANIZATION REPORT

NUMBER

NSWCCD-23-TM-2009/64

9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES)

Attn PEO SHIPS, PMS 325G

Commander

Naval Sea Systems Command

1333 Isaac Hull Avenue, SE Building 197

Washington Navy Yard, DC 20376

10. SPONSOR/MONITOR’S ACRONYM(S)

PMS325G

11. SPONSOR/MONITOR’S REPORT

NUMBER(S)

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DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited.

13. SUPPLEMENTARY NOTES

PAO approval received from NSWC Carderock, Congressional and Public Affairs Branch, Code 3830 on 11/25/2009.

14. ABSTRACT

This document identifies the design and certification process, technical data, analyses, and testing that is necessary to ensure that US Navy craft can be effectively and efficiently moved by required transportation assets and modes, according to the user’s requirements.

15. SUBJECT TERMS

Transport, Transportability, Design, Certification, Trailer, Prime Mover, Road, OTR, Ship, Maritime, Sealift, Aircraft, Internal Air Transport, IAT, Guidance

16. SECURITY CLASSIFICATION OF:

17. LIMITATION

OF ABSTRACT

18. NUMBER

OF PAGES

19a. NAME OF RESPONSIBLE PERSON

Willard Sokol, III

a. REPORT

Unclassified

b. ABSTRACT

Unclassified

c. THIS PAGE

Unclassified

See 12.

19b. TELEPHONE NUMBER (include area code)

757-462-3523

Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18 ii

This page intentionally left blank iii

Contents

Page

Figures ................................................................................................................................................. vi

Tables .................................................................................................................................................. vii

Administrative Information ............................................................................................................ viii

Acknowledgements ........................................................................................................................... viii

Summary

Introduction

Background

Objective

Scope

Transportation Modes

Over-the-Road Transport

Maritime Transport

Internal Air Transport

Governing Documents

Certification Responsibilities

Over-the-Road

Maritime

Internal Air Transport

Special Modes

Transport Mode Requirements

Weight Definitions

Craft Weight:

Trailer Weight:

Dimension and Weight Requirements

Over-the-Road Transport

Maritime Transport

Internal Air Transport iv

Over-the-Road Transport Specific Requirements

Operational Area

Terrain

Prime Mover Interface

Electrical Connections

Trailers and Cradles

Maritime Transport Specific Requirements

Well Deck Operations

Dedicated Stern Launch and Recovery

Movement with Cranes and Davits

Internal Air Transport Specific Requirements

Load Plan Development

Slow Speed and Static Load Capacity

Transport Packaging Design

Restraint System Design

Determine Required Loads

Tie-down Arrangement and Analysis

Over-the-Road Transport Tie-down Arrangement and Analysis Details

Maritime Transport Tie-down Arrangement and Analysis Details

Air Transport Tie-down Arrangement and Analysis Details

Tie-down Attachment Design

Tie-down Strap Selection

Restraint System Testing

System Verification

Physical Validation

Packaging for Transport

Dimensions

Testing

Weight

Tie-down Fitting Pull Test

Road Testing

Maritime Testing

Aircraft Validation and Load Testing v

Documentation and Labeling

Documentation

Equipment Labeling

Symbols, Abbreviations, and Acronyms

References

Distribution

Appendix A: Design and Certification Process Summary .......................................................... A-1

Appendix B: Design Parameters Matrix ....................................................................................... B-1

Appendix C: Trailer Guidance ...................................................................................................... C-1

Appendix D: Design Example ........................................................................................................ D-1 vi

Figures

Figure 1. Craft Over-the-Road Transport

Figure 2. Craft on a Cradle on a Flatbed Trailer

Figure 3. Internal Air Transport

Figure 4. Aircraft Cargo Compartment Dimensions

Figure 5. Soft Soils at Launch Site

Figure 6. Water Depth at Launch Site

Figure 7. Prime Mover Hitch Height and Rear Axle Distance

Figure 8. Trailer Electrical Connections

Figure 9. Rigid Inflatable Boat on Typical Shipping Cradle

Figure 10. Examples of Bow Stops

Figure 11. Stern Gate Launch and Recovery Operations

Figure 12. Kickstand Supporting Craft in Well Deck

Figure 13. Ship’s Boat Stowed in Davit

Figure 14. Air Force Material Handling Equipment

Figure 15. Critical Points for Aircraft Loading

Figure 16. Modular Approach Shoring for Airlift

Figure 17. Results of Improper Restraint

Figure 18. Unique Equipment Tie-downs on Navy Ships

Figure 19. Examples of Different Tie-down Fittings vii

Tables

Table 1. Comparative Cost to Transport Equivalent Volume of Cargo (US - Kuwait)

Table 2. Governing Documents for Typical Transport Modes

Table 3. Reference Documents for Special Transport Modes

Table 4. General Limits for Over-the-Road Movement

Table 5. US Navy Ship Deck Heights for Vehicle Stowage (Ref 8)

Table 6. US Navy Ship Deck Strengths (Ref 8)

Table 7. US Navy Ship Vehicle Ramps and Stern Gates (Ref 8)

Table 8. Typical Prime Movers

Table 9. Restraint Accelerations for US Navy Craft Transport Modes viii

Administrative Information

This work was performed by the Combatant Craft Division (Code 23) of the Ship

Systems Integration and Design Department at the Naval Surface Warfare Center, Carderock

Division (NSWCCD). This effort was sponsored by the US Navy Small Boats Program Office, PMS 325G, in support of all small boats and craft acquisitions.

This document (NSWCCD-23-TM-2009/64 Rev B November 2009) replaces Revision A, which is obsolete and should be destroyed.

Acknowledgements

The author wishes to thank Mr. J.M. Coughlin, Program Manager at the US Navy Small

Boats Program Office (PEO Ships, PMS 325G), for sponsoring the original development of this guide, and Mr. Denis Bushey, PMS 325G for his overall management direction for revision B.

The experience and knowledge of the following individuals contributed greatly to this revised guide: Jason Marshall, Dan Demko, Jack Mathias, Allan Demmelmaier, and Tom Harrell. Ms.

Elena Murphy provided editorial and formatting assistance, and Mr. Michael Riley served as technical editor. The collective support of all these individuals is sincerely appreciated.

Summary

This document provides design guidance to assist boat builders, designers and engineers in the design, fabrication, installation, inspection, testing, and certification for safe and efficient means of transporting craft over-the-road (OTR), by sea, and by air. The information is intended to provide a useful tool set, but it should not preclude the use of other good engineering practices or processes that also support delivery of safe and effective capabilities for craft transport. It presents a collection of available information to be updated as new lessons are learned, and as new materials or techniques are developed. The following list is an outline of the transportability design process presented in this guide.

o Transportation Modes o Over-the-Road Transport o Maritime Transport o Internal Air Transport (IAT) o Governing Documents o Special Modes (Rail, External Air Transport, Low Velocity Air Drops, etc.)

o Certification Responsibilities o Transport Mode Requirements o Weight Definitions o Dimension and Weight Requirements o Over-the-Road Transport Specific Requirements o Maritime Transport Specific Requirements o Internal Air Transport Specific Requirements o Transport Packaging Design o Restraint System Design o Determine Required Loads o Tie-Down Arrangement and Analysis o Tie-Down Attachment Design o Strap Selection o System Design Verification o Physical Validation o Testing o Documentation and Labeling o Documentation o Equipment Labeling

Introduction

Background

Transportability is the ability of a small boat or craft to be safely and efficiently moved over-the-road, by sea, or by air modes of travel as required. This capability is just as important as the other primary mission capabilities provided by the craft. Requirements documents and procurement contracts specify the intended modes of transportation for a craft as well as the design criteria and verification tests required to ensure safe and efficient means of transport.

Training packages and maintenance or repair information related to transport modes must also be prepared and delivered during the acquisition process.

The overall success of a Navy craft acquisition program depends upon the timely exchange of key information and the knowledge of collaborating participants (both private industry and government). Acquisition engineering agents must ensure that craft requirements are clearly delineated. Boat builders must ensure they understand the requirements, apply applicable design standards and fabrication practices, and deliver products that meet the requirements. The government technical point of contact (TPOC) must ensure that proper design reviews and tests are performed to verify that the system design meets the requirements. Before a new craft is accepted and authorized for contract payment, a certification process is performed by the TPOC and an independent team of government subject matter experts to certify the system is safe and effective.

The layout of this guide includes technical information as well as “TIPS” that highlight lessons learned and cautions for avoiding common issues. Typical contract requirements are presented. Best practices for achieving weight allowances and size limitations are summarized, and lessons learned related to detailed design of methods for securing craft in required modes of transportation are reviewed. Acceptance testing methods and boat builder information packages are presented, and design certification processes established to mitigate the risk of unsafe conditions that would prevent or significantly delay transport operations are discussed. Appendix

A provides a detailed check off list of all the design elements presented in this guide, and

Appendix B provides a design parameter matrix that serves as a useful summary of the key factors to consider when designing restraint systems for each mode of transport. Appendix C provides guidance for development of trailer requirements and specifications. Appendix D illustrates a simplified design example for all transportation modes.

Use of the guide and close communication with the TPOC should result in an adequate design and craft acceptance. The goal of every craft TPOC is to help the builder design, fabricate, and test for the applicable modes of craft transportation.

In the context of this guide, “success” is defined as final delivery of a new craft to an operational squadron with all required transportation modes certified as safe and effective for military use.

TIP: Successful acquisition and delivery of a new craft relies on collaborative teams of knowledgeable individuals. Ask the TPOC immediately if there are questions related to design requirements, applicable standards, or acceptance criteria.

Objective

This document provides design guidance to assist boat builders, designers and engineers in the design, fabrication, installation, inspection, testing, and certification for safe and efficient means of transporting craft over-the-road, by sea, and by air. References for both Department of

Defense and civilian federal air and land transportation regulations are provided, and certification processes are summarized so that (1) designers and boat builders understand the importance of information packages required by the contract, and (2) government engineers (in-training) understand the responsibilities of a government Technical Point of Contact (TPOC).

Scope

This guide is generally applicable to the design, fabrication, and certification of safe and effective means for transporting US Navy boats and craft. It conveys typical government preferences and expectations as an educational tool for builders offering boats and craft on the

General Services Administration (GSA) Federal Supply Schedule (FSS). The information contained herein is not contractually binding and does not supersede contract requirements.

The design guidance presented in this document is a collection of lessons learned and best practices for consistent application across various platforms to ensure that required modes of transportation can be achieved safely and efficiently. This information provides a useful tool set, but it should not preclude the use of other good engineering practices or processes that can also deliver safe and effective capabilities for craft transport.

Transportation Modes

The following sections provide an introduction to the three primary modes of transporting Navy craft, and how certification is achieved for each mode. Some craft are required to be transported by all over-the-road, sea, and air modes of transportation, while others may only require one or two modes. This section introduces the range of technical information and key design parameters that will be presented in later sections of this guide.

Over-the-Road Transport

Movement by trailers like the one shown in Figure 1 on primary and secondary roads is a requirement for almost all U.S. Navy craft. Craft requiring over-the-road transport may also be moved on shipping cradles like the one shown in Figure 2. The boat builder will typically be expected to address the following topic areas for over-the-road transport requirements:

o Craft and trailer size and weight limits o Types of road surface conditions o Interface to the prime mover o The craft’s interface to its trailer or cradle o Packaging for transport o Restraint of the craft as cargo o Physical size and weight validation and testing o Design documentation including instructions for operation and equipment labeling

Figure 1. Craft Over-the-Road Transport

Figure 2. Craft on a Cradle on a Flatbed Trailer

Maritime Transport

Transportation on maritime shipping is also a requirement for almost all boats and craft.

This is primarily accomplished on U.S. Navy ships, but there may be requirements for transport on Landing Craft Air Cushion vehicles or military sealift ships. The boat builder will typically be expected to address the following topic areas for maritime transport requirements:

o Craft and trailer weight o Dimensions for stowage and movement on ship o Load planning (access ramp angles, crest clearances, and tolerances) o Hoisting with pier side or shipboard cranes and davits o Packaging for transport o Restraint of the trailer in hoisting o Restraint of the craft and trailer (or cradle) to the ship

Internal Air Transport

When transport in an aircraft is required, the intended mode of transportation is typically by US Air Force cargo plane (C-130, C-17, or C-5) on the trailer using the intended prime mover

(or material handling equipment available at the airfield). Figure 3 shows a craft being loaded with its trailer onto a cargo plane. The boat builder will typically be expected to address the following topic areas for air transport requirements:

o Cargo size and weight limitations for each aircraft o Load planning (access ramp angles, crest clearances, and tolerances) o Trailer component strength at slow speeds and static loads o Packaging for transport o Restraint of the craft and trailer to the aircraft

Figure 3. Internal Air Transport

Air transportation is typically the most expensive mode of transport. Before these requirements are imposed the TPOC typically confers with end-users and acquisition program managers to ensure the air transport requirements are validated by higher naval authority. Table

1 provides historical operational cost information from reference 3 to illustrate the potential impacts on life cycle costs.

Table 1. Comparative Cost to Transport Equivalent Volume of Cargo (US - Kuwait)

Aircraft

Maritime Transport

Cost [$K, FY07]

Air Transport Cost

[$K, FY07]

C-130 37 295

C-17 205 347

C-5 371 715

Governing Documents

Table 2 lists the governing documents that are applicable to the different transport modes covered in this guide.

Table 2. Governing Documents for Typical Transport Modes

Mode Document Applicability

All MIL-STD-1366 General interface requirements

MIL-STD-209 Requirements for tie-down fittings (rail transport excluded)

Over-the-

Road

23CFR658

Specific design constraints for highways that are part of the National Network (Interstates and US numbered highways) in the continental United

States (CONUS)

49CFR393 Detailed operation and equipment specifications for highway safety, primarily related to the prime mover, trailer, and restraint of the craft as cargo 49CFR571 (Federal Motor

Vehicle Safety Standards)

Maritime NSTM Chapter 583 Lifting of craft and trailers with cranes or davits

Ship’s Loading Characteristics

Pamphlet (SLCP)

Information particular to amphibious assault ships, published by each ship annually

Wet Well Manual Information regarding well deck operations

Air MIL-HDBK-1791 Detailed guidance to internal air transport

Certification Responsibilities

The Combatant Craft Division (CCD) of Naval Surface Warfare Center, Carderock

Division is responsible for verifying that boats and their trailers can be transported in all required

Estimated costs assume the craft fills the entire payload volume of the aircraft.

References to the Code of Federal Regulations (CFR), reference 2 are typically abbreviated as xxCFRyyy.zzz, where xx is the ‘Title’ number, yyy is the ‘Part’ Number, and zzz is a specific section number.

modes. The design characteristics, technical data, and testing required to execute this responsibility should be included in the terms of the contract or solicitation. If certifications are required, CCD is responsible for requesting them from the appropriate certification authority.

Over-the-Road There are typically no formal certifications required for OTR transport beyond those required by the Department of Transportation. The current exception to this applies to the

Medium Tactical Vehicle – Replacement (MTVR) as a prime mover, which requires additional testing and formal approval in a naval message from the US Marine Corps Motor Transport program office.

Maritime

There is no formal certification process to carry a boat as deck cargo on most Navy and sealift ships (either on the weather deck or between decks), but documentation of restraint capacities and other shipping information is often required. In some instances the TPOC may be required to coordinate demonstrations or tests with different ships and operational units to ensure that the craft can be transported on the ship successfully. To operate from Landing Craft Air

Cushion vehicles (LCACs), a formal certification process is required that leads to addition of the craft and its restraint system to the Safe Engineering and Operations (SEAOPS) Manual for the

LCAC.

Internal Air Transport requires a rigorous, formal evaluation and certification process.

The US Air Force’s Air Transportability Test Loading Activity (ATTLA) is responsible for certifying cargo such as boats for flight in Air Force aircraft. Certification for Navy or Marine

Corps aircraft is the responsibility of the Naval Air Systems Command (NAVAIR).

Air Force certification is generally accepted for transport on Navy and Marine Corps aircraft that are common between the services, which currently excludes variants of the C-130T and KC-130 (tanker). These constitute a comparatively small number of aircraft, and are not typically used for air transport. ATTLA is, therefore, the primary certification authority for internal air transport of US Navy boats. Where users require Navy C-130 transport, the TPOC should identify which aircraft variants are available to the operators to determine the certifying authority and the data needed for certification.

Special Modes

Unique transportation requirements primarily involve special mission requirements, such as rail car transport, helicopter sling loading, low velocity air drop, and special storage cradles (e.g. stowage for the admiral’s barge). These are not typically employed for craft, and are outside the scope of this guide, however, initial information for these modes is provided in documents listed in Table 3.

Table 3. Reference Documents for Special Transport Modes

Document Special Mode Guidance

MIL-STD-1366 Rail Transport

MIL-STD-913 Helicopter sling loading

MIL-STD-814 Low velocity air drop

Naval Ships Technical Manual

(NSTM), Chapter 583, Volume 2

Special storage cradles

Transport Mode Requirements

Weight Definitions

Designers and builders are responsible for determining weights of craft and trailers for verifying trailer load capacities and tie-down strength calculations. The following items should be included when determining design weights (i.e. total weight) for the different transport modes unless otherwise specified by the TPOC.

Craft Weight:

Over-the-Road Transport

Completed craft weight

Full fuel & operating fluids

Deduct water in jets, strainers, etc (free flood volumes)

Maximum combat load-out including mission equipment (fittings, weapons, ammo, etc.)

and personnel at 285 lbs each

Deduct personnel (at 220 lbs each) for resultant personnel gear weight

5-10% margin

Maritime Transport

Completed craft weight

Full fuel & operating fluids

Deduct water in jets, strainers, etc (free flood volumes)

Mission equipment and personnel gear identified by TPOC (typically may include weapons and ammo)

10% margin (for hoisting)

Air Transport

Completed craft weight

5% fuel

Deduct water in jets, strainers, etc (free flood volumes)

Additional cargo weight identified by TPOC (typically may include equivalent weight of additional fuel)

For air transport the weights of the craft and trailer should be each rounded up to the nearest 1000 pounds unless otherwise specified by the TPOC.

Trailer Weight:

Full operating fluids

Tools/Stowages

Tie-down straps

Miscellaneous Material required for over-the-road transport (e.g. boat covers, etc)

5-10% margin (10%, minimum for hoisting in maritime transport)

Dimension and Weight Requirements

The total weights and dimensions of the craft and its trailer (and/or cradle) are the most important parameters for transport design. The following sections provide design criteria, including weight, height, length, and width limits for each transportation mode.

Over-the-Road Transport.

Most craft are typically required to be capable of road transport on U.S. and allied highways. The exception to this general requirement is limited to very large craft that are not transported to their mission area over-the-road (e.g. coastal patrol vessels). Table 4 provides height, length, width, and weight criteria for approved travel on CONUS and NATO highways.

The prime mover will be allowed unrestricted travel (movement) if the parameters listed in the first row of Table 4 are achieved.

TIP: Typically, the designer and builder should design for unrestricted travel in

CONUS. If this is not possible, design for travel with minimal restrictions is preferred.

The allowable limits on height, length, width, and weight will typically be identified in the terms of the solicitation or contract when restricted road transport is the intended mode of OTR transport.

TIP: Consult with the TPOC as soon as possible for additional information if restricted road transport is specified or is determined by design to be most practical.

If operators require a “rough terrain” capability, specific testing by the government over a range of terrain types is required. General guidance concerning testing of on-road and off-road trailers is included in Appendix C.

Table 4. General Limits for Over-the-Road Movement 5

Height

[in]

Length

[in]

Width

[in]

Weight, Combined: Applies to

Craft, Trailer, and Prime Mover

CONUS

Unrestricted

(13’-6”)

(~40’-0”)

(8’-6”)

- Satisfies Federal Bridge Gross

Weight Formula

- 80,000 lbs. Combined Gross

Vehicle Weight (incl. Prime Mover)

- Single Axle load: 20,000 lbs

- Tandem Axle Load: 34,000 lbs

- Triple Axle Load: 42,000 lbs

CONUS Minimal

Restrictions

(13’-6”)

(~40’-0”)

(10’-0”) Same as CONUS Unrestricted

CONUS with

Restrictions

(15’-0”)

(60’-0”)

(12’-0”)

- Single Axle load: 20,000 lbs

- Tandem Axle Load: 34,000 lbs

- Triple Axle Load: 42,000 lbs

NATO Highways

Unrestricted

4.00 meters

10.00 meters

2.50 meters

- Single axle load: 10,000 kg

- Tandem axle load: 16,000 kg

Korea Highways

Unrestricted

4.00 meters

17.00 meters

3.00 meters

- Single axle load: 10,000 kg

- Tandem axle load: 16,000 kg

- Triple Axle Load: 40,000 kg

“Minimal restrictions” as cited in Table 4 (row 2) reflect a typical threshold where permits are required, but are relatively easy to obtain, and the travel does not require significant logistical support, such as escort vehicles or specified schedules and routes that are characteristic of travel

(movement) “with restrictions” (shown in row 3).

TIP: Boat builders should ensure trailer designers use axle spacing identified in reference 7 for final estimates of maximum axle loads.

Maritime Transport.

All craft that can be transported over-the-road are typically required to be capable of maritime transport as deck cargo (unless specifically stated otherwise in the terms of the solicitation or contract). Height and weight restrictions may be more limiting on ships than for over-the-road transport (depending upon the intended transport ships and stowage location on open weather decks or below decks via access ramps). MIL-STD 1366E provides height, width, and weight restrictions for military sealift ships.

Applicable permitting limits vary from state to state, but generally do not exceed the dimensions and weights identified in this table Federal length limits in 23CFR658.13 apply only to semitrailers and combination semitrailer-trailer configurations.

For craft OTR design, trailered length should be limited to approximately 40 feet, if possible, and boats carried on semitrailers should conform to the length limit of 48 feet whenever possible.

Tables 5, 6, and 7 provide deck height limits, weight limits, access ramp slope, and ramp width limits for Navy ships typically used to transport small boats and craft. Unless otherwise specified, trailers hauling a craft should be able to pass over a ramp with a slope equal to no less than 15 degrees.

The uniform distributed load (UDL) limits for decks in ships is an equivalent deck pressure calculated using the total weight (craft and trailer) and the trailer contact areas to the deck.

Experience has shown that small boats and craft on trailers seldom come close to these limits.

TIP: For a conservative design approach, subtract 6 inches from the deck heights and ramp widths provided in Tables 5 and 7.

Table 5. US Navy Ship Deck Heights for Vehicle Stowage (Ref 8)

Ship Class

Vehicle Handling & Stowage Location

Clear Deck Height [in]

Remarks

LCM 8 Main Deck N/A Open Deck

LCU 1610 Main Deck N/A Open Deck

LCAC Main Deck N/A Open Deck

LSD 41

Main Deck 156

Height at opening between the fixed ramp and aft end of main deck

01 Level 180

LSD 49

2nd Deck 180

Main Deck 156 Height at opening between the fixed ramp and aft end of main deck

01 Level 180

LPD 4/7 2nd Deck 190/114 114 inches to bottom monorail train

LHA 1 2nd Deck 168/109.5 109.5 inches to bottom monorail train

LHD 1 2nd Deck 168/109.5 109.5 inches to bottom monorail train

LPD 17

1st Platform (Main-V) 191 150 inches in forward vehicle area

2nd Deck (Upper-V) 133 143.5 inches ramp to flight deck

Table 6. US Navy Ship Deck Strengths (Ref 8)

Class

Well Deck Upper Vehicle

Deck Main Vehicle

Deck 01 Level 02 Level 03 Level

UDL

(psf)

Wheeled Vehicle

UDL

(psf)

Wheeled Vehicle

UDL

(psf)

Wheeled Vehicle

UDL

(psf)

Wheeled Vehicle

UDL

(psf)

Wheeled Vehicle

UDL

(psf)

Wheeled Vehicle

LSD 41 300 M1A1 300 M55 N/A N/A 300 M55 N/A N/A N/A N/A

LSD 49 300 M1A1 300 M55 N/A N/A 300 M55 N/A N/A N/A N/A

LHA 1 550 M1A1 550 M55 N/A N/A N/A N/A 550 M55 550 M55

LHD 1 500 M1A1 500 M55 N/A N/A N/A N/A 500 M55 500 M55

LPD 4/7 300 M60 300 M62 N/A N/A N/A N/A N/A N/A N/A N/A

LPD 17 627 M1A1 627 M923 627 M923 N/A N/A N/A N/A N/A N/A

Table 7. US Navy Ship Vehicle Ramps and Stern Gates (Ref 8)

Class

Slopes (Degrees)

Clear Width

(Inches) Ramp Location

Capacity (lbs)

Remarks

LCM 8 20 168 Bow Ramp Well Deck 120,000 Hinged

LCU 1610

20 178 Bow Ramp Main Deck 140,000 Hinged

12 178 Stern Gate Main Deck 140,000 Hinged

LCAC

14 340 Bow Ramp Main Deck 140,000 Hinged

14 178 Stern Ramp Main Deck 140,000 Hinged

LSD 41

N/A 600 Stern Gate Well Deck 140,000 Hinged

14.5 120 Portable Ramp Well Deck/2nd Deck 34,000

14.5 120 Fixed Ramp 2nd/Main Deck 34,064

15 138 Fixed Ramp Main Deck/01 Level 34,064

15 150 Fixed Ramp 01 Level/Helo Deck 34,064

LSD 49

N/A 600 Stern Gate Well Deck 140,000 Hinged

16/12 600 Well Deck Well Deck/2nd Deck 140,000 Fixed, Double Knuckle

15 138 Fixed Ramp 2nd Deck/Main Deck 34,064

15 138 Fixed Ramp Main Deck/01 Level 34,064

15 138 Fixed Ramp 2nd Deck/Helo Deck 34,064

15 150 Fixed Ramp 01 Level/Helo Deck 34,064

LPD 4/7

N/A 600 Stern Gate Well Deck 140,000 Hinged

12 600 Well Deck Well Deck/3rd Deck 90,000 Fixed

25 214 Upper Ramp 3 rd Deck/Main Deck 41,000

LHA 1

N/A 600 Stern Closure Well Deck N/A

15/11 380 Well Deck Well Deck/3rd Deck 140,000 Fixed, Double Knuckle

15 180 Hangar 3rd/Hangar Deck 43,000

15 114 Side port

Ramp Pier/3rd Deck 43,000 Portable

LHD 1

N/A 600 Stern Gate Well Deck 140,000 Hinged

15/11 600 Well Deck Well Deck/3rd Deck 140,000 Fixed Double Knuckle

15 180 Hangar 3rd /Hangar Deck 43,000 47,000 for LHD2 and Up

15 114 Side port

Ramp Pier/3rd Deck 43,000 Portable

LPD 17

N/A 600 Stern Gate Well Deck 140,000 Hinged

15/11 283 Well Deck Well Deck/1st Plat 140,000 Fixed, Double Knuckle

15 138 Bridge Ramp 1st Plat/2nd Deck 47,000

15 138 Fixed Ramp 1st Plat/2nd Deck 47,000

15/11 138 Fixed Ramp 2nd/Main Deck 47,000 Fixed, Double Knuckle

15 114 Side port

Ramp Pier/3rd Deck 47,000 Portable (P), Hinged (S)

Figure 3 illustrates the close tolerances associated with loading a large craft into an aircraft. The allowable cargo dimensions in the cargo compartments of Air Force C-5, C-17, and

C-130 aircraft from reference 7 are shown in Figure 4.

TIP: If the C-130 is the specified air transport mode, the craft must allow for a safety aisle for the aircrew and is subject to maximum axle and tongue loads, depending on its position in the aircraft. These constraints are outlined in MIL-

STD-1366 and MIL-HDBK-1791.

The maximum cargo weight (based on optimum flight conditions) is limited to 24,000 lbs for the C-130, 130,000 lbs for the C-17, and 178,000 lbs for the C-5 [Reference 7]. Typically, a craft and trailer will not approach the limits of the larger C-17 and C-5 aircraft, but they may require consideration if it is intended to be transported with the prime mover, or a second craft, or other gear.

Under Wing Aft of Wing

C – 130

C - 5

C - 17 C - 17

Figure 4. Aircraft Cargo Compartment Dimensions

NOTE: If craft is intended to be transported as Air Cargo on a pallet in a C-130 the maximum height of the craft should be 100” from the pallet surface to the greatest vertical extent of the craft.

Over-the-Road Transport Specific Requirements

Operational Area The intended operational environment imposes constraints on the boat and trailer package. These constraints primarily include the dimension and weight limits identified earlier, terrain types, and launch and recovery site conditions.

Terrain. Transportation over-the-road requires traversing various types of terrain.

Categories and descriptions of these terrain types are described below. More detail for each type, including roughness measurements, is included in Appendix C.

Primary Roads - (high quality paved, secondary pavement, and rough pavement)

- All may consist of two or more lanes, all weather, maintained, hard surface (paved) roads with good driving visibility used for heavy and high density traffic. These roads have lanes with a minimum width of 108 inches, road crown less than 2 degrees and the legal maximum gross vehicle weight/gross combined weight (GVW/GCW) for the county and state is assured for all bridges.

Secondary Roads - (loose surface, loose surface with washboard and potholes, and Belgian block) - These roads are one or more lanes, all weather, occasionally maintained, varying surface (e.g., large rock, crushed rock and gravel) intended for medium-weight, low-density traffic. These roads have no guarantee that the legal maximum GVW/GCW for the county and state is assured for all bridges.

Trails - One lane, unimproved, seldom maintained loose surface roads, intended for low density traffic. Trails have no defined road width and can include large obstacles

(boulder, logs, and stumps) and no bridging.

Cross-Country Terrain - Vehicle operations over terrain not subject to repeated traffic. No roads, routes, well-worn trails, or man-made improvements exist. In addition, cross-country terrain can consist of tank trails with crushed rock or having large exposed obstacles (rocks, boulders, etc).

Most Navy craft typically require transport over primary and secondary roads. For craft not normally trailered (i.e. moved using a shipping cradle on a flat-bed truck), only transportation over primary roads is typically required. If operators require a “rough terrain” capability, specific testing over the range of all terrain types is required. General guidance for development of a “rough terrain” trailer is included in Appendix C. The TPOC can address any questions regarding specific terrain requirements that are not included in the terms of the contract or solicitation.

Launch and Recovery Site. Launch and recovery from a ramp with primary or secondary road surface characteristics is typically required for a trailered craft. Defining the requirement for other methods of launch and recovery is the shared responsibility of the TPOC and the end-users.

In defining this requirement, three fundamental methods of launching a boat are typically considered: ramp launching, launching over an embankment, or by hoisting the boat directly into the water. The applicable requirements for hoisting the boat directly into the water are covered in detail in reference 1. For ramp launching, or for launching over an embankment, accessibility, approach slope (and potential need for additional braking), terrain type, and water depth, are factors that should be considered. Figure 5 and Figure 6 show extreme examples of difficulty that may be encountered in launch and recovery operations in unimproved rough-terrain areas.

Figure 5. Soft Soils at Launch Site

Figure 6. Water Depth at Launch Site

Prime Mover Interface

Dimensions and Capacities. Table 8 provides typical dimensions and tow capacities for prime movers often used to transport craft. This table should be used to establish gross vehicle weight ratings, critical dimensions for trailer hitch types, height ranges, cresting angles, and aircraft load plans.

TIP: The trailer hitch height and distance to rear axle shown in Figure 7 are key parameters for determining the ability of trailers to clear the crest of a ship or aircraft loading ramp.

Electrical Connections. All trailers should have both 7-pin and 12-pin connectors designed to interface directly with the intended prime mover’s electrical system. 7-Pin connectors should be designed in accordance with SAE J560 and 12-Pin connectors should be designed in accordance with Military Standard (MS) 75021. Commercially-available prime movers, including militarized variants like the Light Service Support Vehicle (LSSV) have standard 12-volt systems with a 7-pin (flat terminal) commercial round connector shown in

Figure 8. Tactical vehicles (e.g., MTVR, High Mobility Multi-Wheeled Vehicle (HMMWV), or

Mine Resistant Ambush Protected (MRAP)) have standard NATO 24-volt systems with a 12-pin connector, NSN5995-01-544-5774 (also shown in Figure 8).

Table 8. Typical Prime Movers

Prime Mover Hitch

Height

[in]

Distance to

Rear Axle [in]

Rated Tow

Capacity [lbs]

Wheelbase

[in]

Notes

LSSV 18.5 64 13,000 167 1, 3, 5, 8, 10

LSSV (EMP) 26.5 62 13,000 167 1, 2, 3, 6, 10

Ford F-550

(Crew Cab) 27 68 16,000 176.2 3, 6, 10

FL-80 23 77 36,500 252 4, 9, 10

MTVR MK23 39 56 22,400 184 4, 6, 10

MTVR MK31

(pintle) 34 36 22,400 184 4, 7, 10

MTVR MK31

(fifth wheel) 57.5

28.3 (forward of rear axle) 94,000 184

HMMWV 24.5 40 4,200 Varies 4, 10

MRAP 31 35 Not Available Varies 4

Notes:

(1) LSSV: Chevrolet Silverado 2500HD variant with diesel engine.

(2) Enhanced Mobility Package (EMP): LSSV Suspension Option

(3) Typically Ball Hitch / 2-inch Receiver

(4) Pintle Hitch

(5) Measurement taken with trailer loaded

(6) Measurement taken with no trailer hooked up

(7) Measurement taken with fifth wheel loaded (~12,000 lbs), suspension raised (~50%)

(8) LSSV axle ratings are 4500/6084 lbs (front/rear), when evaluating Federal Bridge Gross

Weight formula

(9) FL80 axle ratings are 11000/51000 lbs (front/rear), when evaluating Federal Bridge Gross

Weight formula

(10) Tow Capacities may be reduced by the weight of any cargo carried on prime mover.

Height

Distance to Rear Axle

Figure 7. Prime Mover Hitch Height and Rear Axle Distance

NATO 12-pin 24 volt Connector7-pin 12 volt Connector

Figure 8. Trailer Electrical Connections

Trailers and Cradles

The trailer and the shipping cradle are typically referred to as ancillary equipment in solicitations or contract documents. Figure 9 shows an example of a craft supported by a cradle on a flat bed trailer. Design considerations for these components are outlined in this section.

Appendix C provides additional detail as a guide in developing on-road and off-road trailer specifications, craft contract requirements, and specialized government test plans for certification of rough terrain trailers. Additional guidance is also available from the National Association of

Trailer Manufacturers in reference 9.

Trailer Size and Weight. The placement of the craft on the trailer should generally result in a combined (craft and trailer) center of gravity located to produce approximately 10% of the gross vehicle weight (GVW) on the tongue for a hitched trailer, or 20-30% of the GVW on the kingpin for a fifth wheel trailer.

Trailer gross vehicle weight rating (GVWR) should be no less than the combined weight of the craft and the trailer plus margins. Due to discrete increments of trailer component weight ratings (e.g. axles and brakes), assumed margins may be adjusted to achieve a reasonable weight estimate. The target GVWR should be approximately 105% to 110% of the gross vehicle weight at delivery (without craft and trailer margins).

Figure 9. Rigid Inflatable Boat on Typical Shipping Cradle

TIP: For smaller craft, the trailer should be capable of unrestricted transport on

CONUS highways when it is in an unloaded condition.

Construction. Trailers and cradles should always be of a heavy-duty construction, using corrosion- and rot-resistant (or coated) materials and components. Trailer components are likely to be submerged frequently, are regularly exposed to the elements, and typically receive little maintenance during its life cycle. Specific details for component material selection are included in the general guidance in Appendix C.

Craft Interface. The craft is typically supported by solid bunks or roller bunks. Some contracts may require low friction materials to allow for easier or more rapid launch and recovery. If practicable, the bunks should be located along the keel, hull, and chine to provide support at craft transverse bulkheads, longitudinals (especially in way of engine foundations), and frames.

TIP: Support points should not be located in way of spray/lifting strakes or hull appendages (e.g. raw water suction, waterjet grates, depth sounder, etc), and should be positioned and sized for adequate load distribution when the craft is subjected to all applicable accelerations (See Table 9 for road, sea, and air transport design load factors).

All Navy trailers have a bow winch and a bow stop. Several common examples are shown in Figure 10. If not defined in the terms of the solicitation or contract, the winch and its supporting structure should be designed to the same load as the bow eye with a minimum system safety factor of 1.5 on the ultimate strength.

TIP: There are commercially available powered winches that may be capable of parting the cables supplied by the manufacturer. If this condition exists consult with the TPOC regarding use of higher strength cables than those supplied by the manufacturer.

The bow stop should have sufficient strength to resist the craft’s maximum thrust at zero speed without yielding, and it should provide self-centering capability. If large angles during launch and recovery are included in mission scenarios, the contract will typically require fairlead rollers to reduce the loading and prevent damage to the winch or the winch cable. All trailers and cradles must be provided with the correct tie-down quantity and strength. This is discussed in detail in the Restraint System Design section of this guide.

Basic Commercial V - Block

Split BumperSplit Bumper

Figure 10. Examples of Bow Stops

Lighting. All tail lights, side marker, and aft marker lights should be 12v and 24v compatible LED lights using NSN 6210-01-482-6105, 6220-01-482-6113, and 6220-01-482-

5574, or equal lights conforming to MIL-PRF-32212A (Tail Lights) and 32213 (Marker Lights).

Other part numbers may be chosen for other housing colors (tan or black) to suit the application.

The 7 pin and 12 pin connectors should be secured to the end of two “pig-tails” that connect to a common trailer wire harness in a NEMA water tight junction box which houses a properly sized terminal strip and conductors using ring terminals. Means to secure the 12v and 24v wire harness connectors when not connected to a tow vehicle should be provided.

Regulatory Compliance. All highway trailers must adhere to Department of

Transportation regulations, including the applicable regulations in 49CFR393 and 49CFR571.

TIP: Consult with the TPOC as soon as possible for cases where federal regulations for CONUS transit violate a military requirement. For example, the use of permanent reflectors to meet a federal transportation regulation could violate a military requirement for tactical blackout conditions. This situation could be satisfied by the use of removable (temporary) reflectors on the trailer during

CONUS transit.

TIP: Exemptions to federal Department of Transportation regulations can be approved if the craft is intended to be transported on trailers pulled only by military or government vehicles. But exemptions should be avoided if possible because it limits future flexibility to be able to pull the trailer on CONUS highways with non-military or non-government vehicles.

Maritime Transport Specific Requirements

Navy craft are often transported to an operational area onboard a Navy ship as deck cargo.

This form of transport requires accessible lifting and tie-down fittings in addition to the dimensional and weight criteria identified earlier in this guide. This applies to loading on roll-on/roll-off (RO/RO) ramps or by lifting the craft and trailer onto the ship with a pier-side or shipboard crane. Design of tie-down fittings is discussed in the Tie-down Attachment Design section of this guide and in reference 6.

Well Deck Operations.

Some craft are intended for operation from specific Navy ships, particularly from the well decks of amphibious assault ships as shown in Figure 11. Operation from a Navy ship may require information on the maintenance and upkeep of the boat, which must be performed while the ship is underway. The TPOC is responsible for defining additional technical data and testing required for certification, which should be identified in the terms of the contract or solicitation.

Launching the boat directly from the well deck may be performed with or without the craft’s trailer. When a trailered launch is required, additional tie-down fittings and length restrictions may apply (this evolution is typically performed on the fold-down stern gate or on the ramp at the head of the well deck). When the craft is to be transported without its trailer in a well deck, the keel must be reinforced to carry the boat’s weight, and additional equipment must be included (such as a cradle, bracing, or the “kickstand” pictured in Figure 12) to prevent the boat from tipping over while the well deck is drained. These considerations should be clarified with the TPOC when well deck launch and recovery is required.

Figure 11. Stern Gate Launch and Recovery Operations

Figure 12. Kickstand Supporting Craft in Well Deck

Dedicated Stern Launch and Recovery.

Ship’s boats intended for use with future or developmental ships with dedicated stern launch and recovery systems, such as the Littoral Combat Ship or the DDG-1000, will have unique interface requirements. Any boat intended for this type of use on a future ship class will have interface requirements clearly defined in the solicitation or contract.

Movement with Cranes and Davits.

Since RO/RO ramp access to a ship is not always guaranteed, all craft and their trailers must also be designed to be lifted onto the ship with a crane. While the craft and trailer may be lifted separately, the most direct method of shipboard loading is to lift them together using the craft’s hoist fittings. Hoisting requirements for the combined weight and center of gravity of the craft and trailer are identified in reference 1. This requires that the tie-down fittings on the craft and the trailer, as well as the tie-down straps be designed for higher loads and safety factors than for over-the-road transport. The design loads for these fittings and straps are discussed in the

Restraint System Design section of this guide.

A craft that is issued for dedicated use on a ship is known as a ship’s boat. For example, a destroyer may have a 7-meter rigid inflatable boat (RIB) onboard at all times. They are typically stowed in a fixed cradle assembly with a dedicated davit as shown in Figure 13. Ship’s boats are not considered deck cargo. Nearly all davits on Navy ships are exclusively used for 7 meter or 11 meter Navy standard RIBs. At-sea hoisting system requirements are covered in reference 10.

Figure 13. Ship’s Boat Stowed in Davit

Internal Air Transport Specific Requirements

Most craft that are air-transportable are loaded into a US Air Force cargo plane (C-130, C-

17, or C-5) on their trailer. In each case, the craft must be capable of being loaded into the plane by its prime mover. Material handling equipment shown in Figure 14 may also be used to load the craft. For a C-5, it is preferable that the craft be able to be loaded through both forward and aft ramps.

Load Plan Development.

A load plan is typically required to be developed by the boat builder as part of the required data package when internal air transport is required. The plan typically includes aircraft dimensional constraints to verify that the craft and trailer can be loaded without interference, and it specifies any shoring that may be required. Figure 15 illustrates the three critical locations of potential interference that should be included in the load plan. An example of a load plan is presented in Appendix D. Dimensions for the cargo compartment cross-sections of all three aircraft are provided in reference 7. Dimensions for the aircraft floor and approach ramps for the

C-130 and C-5 are provided in reference 5. The aircraft floor dimensions and ramp dimensions for the C-17 can be provided by the TPOC.

The prime mover dimensions listed in Table 9 may be used to estimate dimensions used in the load plan. In some instances the TPOC may be able to provide prime mover drawings with detailed dimensions.