Mark-Ups_Appendix_A_-_ETVs-2019-07-24.pdf

APPENDIX A

FOR

ELEVATING TRANSFER VEHICLES

AT

DOVER AIR BASE, DELAWARE

BUILDING 550

CSN: BDV806

DATE: 30 January 2019 Revision 1: 21 June 2019 Revision 2: 15 July 2019 Revision 3: 22 July 2019 Revision 4: 24 July 2019

PREPARED BY:

Ronald D. Parsons Ronald D. Parsons

PROJECT ENGINEER

AFLCMC/EZPAE

Megan E. Blackwell Megan E. Blackwell

REVIEWER

AFLCMC/EZPAE

THIS PAGE INTENTIONALLY LEFT BLANK

Dover AFB – Appendix A - Page i

TABLE OF CONTENTS

1. SCOPE

1.1. GENERAL SCOPE

1.2. DEFINITIONS

1.2.1. ETV END

1.2.2. ETV SIDE

1.2.3. INVENTORY CONTROL SYSTEM (ICS)

1.2.4. INTERFACING CONVEYORS

1.2.4.1. STORAGE CONVEYOR (SC)

1.2.4.2. STAGING DOCK CONVEYOR (SDC)

1.2.4.3. LIFT TRANSFER CONVEYOR (LTC)

1.2.4.4. AIR LINES OF COMMUNICATION (ALOC) CONVEYOR

2. APPLICABLE DOCUMENTS

3. REQUIREMENTS

3.1. SYSTEM DESCRIPTION

3.2. CHARACTERISTICS

3.2.1. OPERATING MODES

3.2.2. ETV NETWORK CONNECTION

3.2.3. CAPACITY

3.2.4. ETV MOVEMENT

3.2.4.1. OPERATING SPEEDS

3.2.4.2. TRAVEL CONSTRAINTS

3.2.4.2.1. HORIZONTAL SPEED CONSTRAINTS

3.2.4.2.2. VERTICAL SPEED CONSTRAINTS

3.2.4.2.3. ACCESS DURING MAINTENANCE

3.2.4.3. PROXIMITY CONSTRAINTS

3.2.4.3.1. PROXIMITY SLOW DOWN

3.2.4.3.2. PROXIMITY STOP

3.2.4.4. CYCLE TIME

3.2.4.4.1. AUTOMATIC MODE

3.2.4.4.2. SEMI-AUTOMATIC AND MANUAL MODES

3.2.4.5. AUTOMATIC LEVELING

3.2.4.6. ACCELERATION AND DECELERATION

3.2.4.7. CONTROLLED STOP

3.2.4.8. EMERGENCY STOP

3.2.4.9. PSE DOOR OPEN TRAVEL INTERLOCK

3.2.4.10. CAB DOOR OPEN TRAVEL INTERLOCK

3.2.4.10.1. AUTOMATIC AND MAINTENANCE MODES

3.2.4.10.2. SEMI-AUTOMATIC AND MANUAL MODES

3.2.4.11. SC STOP PUSH ROD RETRACTED TRAVEL INTERLOCK

3.2.4.12. EXTRACTOR RETRACTED TRAVEL INTERLOCK

3.2.4.13. OVERHEIGHT TRAVEL INTERLOCK

3.2.4.14. CONVEYOR OVERHANG TRAVEL INTERLOCK

3.2.4.15. AISLE OVERHANG TRAVEL INTERLOCK

3.2.4.16. ETV SIDE DRIFT DURING TRAVEL

3.2.5. ETV CONVEYOR INTERFACE REQUIREMENTS

3.2.6. ETV CONVEYOR

R1

Dover AFB – Appendix A - Page ii

3.2.6.1. RIGHT-ANGLE TRANSFER DECK

3.2.6.1.1. ETV PALLET ALIGNMENT

3.2.6.2. TURNTABLE

3.2.6.3. SIDE GUIDES

3.2.6.4. MANUAL OPERATION

3.2.6.4.1. MANUAL OPERATION SAFETY

3.2.6.4.2. MANUAL PALLET STOP RETRACTION

3.2.6.4.3. POWERED ROLLER DISENGAGEMENT

3.2.6.4.4. RIGHT-ANGLE TRANSFER MANUAL OPERATION

3.2.6.4.5. MANUAL PALLET ROTATION

3.2.7. PALLET MOVEMENT DURING TRAVEL

3.2.8. HORIZONTAL AND VERTICAL DRIVE UNITS

3.2.8.1. DRIVE MOTORS

3.2.8.2. MOTOR DRIVES

3.2.8.2.1. MOTOR DRIVE CHARACTERISTICS

3.2.8.2.2. MOTOR DRIVE DIAGNOSTIC UNITS

3.2.8.3. BRAKING

3.2.8.4. HORIZONTAL DRIVE UNIT

3.2.8.4.1. DUAL HORIZONTAL DRIVE SYSTEM

3.2.8.4.2. HORIZONTAL MECHANICAL BRAKE

3.2.8.4.3. HORIZONTAL BRAKE RELEASES

3.2.8.5. VERTICAL DRIVE UNIT

3.2.8.5.1. DUAL VERTICAL LIFT MOTOR SYSTEM

3.2.8.5.2. OPERATOR PLATFORM

3.2.8.5.3. OPERATOR PLATFORM LIFT CABLES

3.2.8.5.3.1. LIFT CABLES LOAD CELLS

3.2.8.5.4. OPERATOR PLATFORM STABILIZATION CABLES

3.2.8.5.5. LIFT CABLE DESIGN

3.2.8.5.6. VERTICAL SAFETY GRABS

3.2.8.5.7. OPERATOR PLATFORM FALL PREVENTION

3.2.8.5.8. LIFT MOTOR AND GEARBOX REPLACEMENT

3.2.8.5.9. EMERGENCY MANUAL LOWERING

3.2.8.5.10. OPERATOR PLATFORM SAFETY PINS

3.2.9. EXTRACTORS

3.2.9.1. EXTRACTOR OPERATION

3.2.9.2. EXTRACTOR MANUAL RETRACTION

3.2.10. STOP PUSH RODS

3.2.10.1. STOP PUSH ROD OPERATION

3.2.11. UNDERCARRIAGE

3.2.11.1. AXLES

3.2.11.2. FRAME

3.2.11.3. TRAILER HITCHES AND TOW BAR

3.2.11.4. VEHICLE SUPPORT WHEELS

3.2.11.5. ETV REPLACEMENT WHEELS

3.2.12. CRANE RAILS

3.2.13. ETV END OF AISLE STOPS

3.2.13.1. END-OF-AISLE STOPS

3.2.13.2. MAINTENANCE AREA STOPS

3.2.14. OPERATOR CAB

3.2.14.1. CAB ROOF

R1

R2

R2,R3

R2

Dover AFB – Appendix A - Page iii

3.2.14.2. CAB WINDOWS

3.2.14.3. CAB DOORS

3.2.14.4. CAB ACCESS

3.2.14.4.1. ETV CONVEYOR WALKWAYS

3.2.14.4.2. ETV ACCESS STAIRS

3.2.14.4.3. ETV EMERGENCY EGRESS LADDER

3.2.14.5. CAB TEMPERATURE CONTROL

3.2.14.6. FIRE EXTINGUISHER

3.2.15. MAINTENANCE ACCESS

3.2.15.1. MAINTENANCE PLATFORMS ON MASTS

3.2.15.2. MAINTENANCE PLATFORM BETWEEN MASTS

3.2.16. SAFETY PLACARDS

3.2.17. BACKUP DECK

3.2.18. HYDRAULICS

3.2.19. PNEUMATICS

3.2.20. ETV SPARE PARTS

3.3. ELECTRICAL CHARACTERISTICS

3.3.1. POWER

3.3.2. POWER FEED RAILS

3.3.3. POWER CONTROL CENTER

3.3.4. DUPLEX RECEPTACLES

3.3.5. VENTILATED BRAKING RESISTOR ENCLOSURE

3.3.6. LIGHTS

3.3.6.1. CONVEYOR LIGHTS

3.3.6.2. HEADLIGHTS

3.3.6.3. INTERIOR LIGHTS

3.3.7. ETV PALLET CONTOUR SCANNER

3.3.8. ETV PALLET CAMERAS

3.3.9. AUDIBLE AND VISUAL WARNING SIGNALS

3.3.9.1. AUDIBLE SIGNALS

3.3.9.2. WARNING LIGHTS

3.3.10. AISLE OBSTRUCTION DETECTOR (AOD)

3.3.10.1. AOD SENSORS

3.3.10.2. AOD ACTIVATION

3.3.10.3. AOD RESET

3.3.11. ETV PROXIMITY SENSORS

3.3.12. ETV END EMERGENCY STOPS

3.3.13. OVER HEIGHT SENSORS

3.3.14. OVERHANG SENSORS

3.3.14.1. CONVEYOR OVERHANG SENSORS

3.3.14.2. AISLE OVERHANG SENSORS

3.3.15. HORIZONTAL AND VERTICAL POSITION SENSORS

3.3.15.1. HORIZONTAL POSITION SENSORS

3.3.15.2. VERTICAL POSITION SENSORS

3.3.15.3. INDIVIDUAL POSITION LOCATIONS

3.3.16. CONVEYOR COMMUNICATION

3.3.17. HOUR METERS

3.4. CONTROLS

3.4.1. COMPLETION OF OPERATIONS

3.4.2. ICS CONTROL CONSOLE

R1

R2

Dover AFB – Appendix A - Page iv

3.4.3. ETV CONTROL CONSOLE

3.4.3.1. POWER PUSH BUTTON

3.4.3.1.1. POWER BUTTON OPERATION

3.4.3.1.2. SLEEP MODE

3.4.3.2. INDICATOR LIGHTS

3.4.3.2.1. HORIZONTAL ALIGNMENT LIGHT

3.4.3.2.2. VERTICAL ALIGNMENT LIGHT

3.4.3.2.3. MAINTENANCE MODE LIGHT

3.4.3.2.4. COLLISION AVOIDANCE LIGHT

3.4.3.3. ETV CONTROL CONSOLE EMERGENCY STOP BUTTON

3.4.3.4. ICS OVERRIDE KEY SWITCH

3.4.3.5. PUSH BUTTONS

3.4.3.5.1. INTERIOR LIGHTS PUSH BUTTON

3.4.3.5.2. PALLET ROTATION DISPLAY BUTTONS

3.4.3.5.3. PALLET PICK UP BUTTON

3.4.3.5.4. PALLET DROP OFF BUTTON

3.4.3.5.5. ETV CONVEYOR MODE BUTTON

3.4.3.5.6. INTERFACING CONVEYOR SELECTOR BUTTONS

3.4.3.6. DISPLAY

3.4.3.6.1. SCREEN TOGGLE SWITCH

3.4.3.6.2. MAIN OPERATION SCREEN

3.4.3.6.2.1. DISPLAY MESSAGES

3.4.3.6.3. GRAPHIC DIAGNOSTIC INDICATOR SCREEN

3.4.3.6.3.1. EMERGENCY STOP INDICATORS

3.4.3.6.3.2. AISLE OBSTRUCTION INDICATORS

3.4.3.6.3.3. OVERHANG INDICATORS

3.4.3.6.3.4. PALLET STOP RETRACTED INDICATOR

3.4.3.6.3.5. CAB DOOR OPEN INDICATORS

3.4.3.6.4. MAINTENANCE SCREEN FUNCTIONS

3.4.3.7. CONVEYOR JOYSTICK

3.4.3.7.1. EXTRACTOR BUTTON

3.4.3.8. TRAVEL JOYSTICK

3.4.4. AUTOMATIC MODE AND SEMI-AUTOMATIC MODE OPERATION

3.4.5. MANUAL MODE OPERATION

3.4.5.1. ADDRESS INPUT

3.4.5.1.1. DIGITAL KEYPAD CHARACTERISTICS

3.4.5.2. MANUAL MODE TRAVEL

3.4.5.3. MANUAL MODE PALLET TRANSFER

3.4.5.3.1. ETV CONVEYOR MODE

3.4.6. MAINTENANCE MODE

3.4.6.1. MAINTENANCE MODE TRAVEL

3.4.6.1.1. TRAVEL JOYSTICK OPERATION

3.4.6.1.2. AUTO ALIGNMENT

3.4.6.2. MAINTENANCE MODE PALLET TRANSFER

3.4.6.3. MAINTENANCE MODE FEATURES

3.4.7. PALLET TRANSFER

3.4.7.1. ETV CONVEYOR PALLET MOVEMENT

3.4.7.1.1. PALLET ALIGNMENT

3.4.7.1.2. SIDE SHIFT

3.4.7.1.3. PALLET ROTATION

R1 R1 R1

R1

R1

R1

R1

Dover AFB – Appendix A - Page v

3.4.7.2. TRANSFER TO/FROM STORAGE CONVEYORS

3.4.7.2.1. STORAGE AND ETV CONVEYOR OPERATION

3.4.7.2.2. STORAGE CONVEYOR ONLY OPERATION

3.4.7.3. TRANSFER TO/FROM POWERED INTERFACING CONVEYORS

3.4.7.3.1. END OF TRAVEL DURING PALLET TRANSFER

3.4.7.3.2. INDEXING DURING PALLET TRANSFER

3.4.7.3.2.1. TRANSFER TO POWERED INTERFACING CONVEYORS

3.4.7.3.2.2. TRANSFER FROM POWERED INTERFACING CONVEYORS

3.4.7.3.2.3. POWERED INTERFACING CONVEYOR ONLY OPERATION

4. QUALITY ASSURANCE PROVISIONS

4.1. INSPECTIONS

4.1.1. PRE-SHIPPING INSPECTION

4.1.2. ON-SITE INSPECTION

4.2. TESTS

4.3. CERTIFICATIONS

THIS AREA INTENTIONALLY LEFT BLANK

THIS PAGE INTENIONALLY LEFT BLANK

Dover AFB – Appendix A - Page 1

1. SCOPE

1.1. GENERAL SCOPE

This appendix establishes the minimum performance, design, fabrication, installation, and test requirements for Elevating Transfer Vehicles (ETVs) for an air cargo handling system at the Air Freight Terminal (AFT), Building 550, at Dover Air Force Base (AFB), Delaware. The work shall be completed in accordance with this appendix, the Cover Purchase Description (PD) and AF Drawing BDV806-01. This appendix covers all equipment, materials, and labor necessary to complete installation of the system.

1.2. DEFINITIONS

1.2.1. ETV END

The ends of the ETV are defined as the edges of the ETV perpendicular to the horizontal travel direction. The interior end faces the other ETV. The exterior end is opposite the interior end.

1.2.2. ETV SIDE

The sides of the ETV are defined as the edges of the ETV that are parallel to the horizontal travel direction. The inbound side is the west side of the ETV and the outbound side is the east side of the ETV.

1.2.3. INVENTORY CONTROL SYSTEM (ICS)

The inventory control system provides control input to the ETV when operating in the automatic and semi-automatic modes.

Control consoles E-1 and E-2 do not control ETV operation in these modes other than input from the emergency stop button.

1.2.4. INTERFACING CONVEYORS

All conveyors the ETV conveyor can interface with are interfacing conveyors. Interfacing conveyors include all Storage Conveyors (SCs), all Staging Dock Conveyors (SDCs), all Lift Transfer Conveyors (LTCs), and all Air Lines of Communication (ALOC) conveyors.

1.2.4.1. STORAGE CONVEYOR (SC)

Storage conveyors are used for storage of 463L pallets. All SC rollers are powered by the ETV extractor. The pallet stop on the SC is released by the ETV extractor.

Dover AFB – Appendix A - Page 2

1.2.4.2. STAGING DOCK CONVEYOR (SDC)

Staging dock conveyors are used to stage pallets for transfer between the ETV and an aircraft loader. The SDC is powered by its own motors. The inbound end of the SDC interfaces with the outbound side of the ETV conveyor.

1.2.4.3. LIFT TRANSFER CONVEYOR (LTC)

Lift transfer conveyors are used to transfer pallets between pallet lifts and the ETVs. The LTC is powered by its own motors.

The outbound end of the LTC interfaces with the inbound end of the ETV conveyor.

1.2.4.4. AIR LINES OF COMMUNICATION (ALOC) CONVEYOR

The ALOC conveyors are used to stage and transfer pallets between the ETV and an over the road tracker trailers. The ALOC conveyors is powered by its own motors. The outbound end of the ALOC conveyors interface with the inbound side of the ETV conveyor.

2. APPLICABLE DOCUMENTS

Applicable documents shall be in accordance with Section 2 of the Cover PD.

3. REQUIREMENTS

3.1. SYSTEM DESCRIPTION

Two ETVs shall be provided. The ETVs shall be the single-rail type with one rail on the ground and a support rail mounted on the ceiling of the Pallet Storage Enclosure (PSE). The ETVs shall transfer one 463L pallet between the ETV conveyor and all interfacing conveyors. Each ETV shall consist of the following:

conveyor, horizontal drive unit, vertical drive unit, extractors, undercarriage, supporting structure, operator cab, feed rail, lights, warning signals, sensors and controls, and other components as specified herein. The ETVs shall provide mechanical power to the SCs for the transfer of pallets between the ETV and the SCs. The ETVs shall provide control information to and receive control information from the SDCs, LTCs, and the ALOC conveyors for the transfer of pallets between the ETV and these conveyors. The ETVs shall interface with the existing ICS.

Both ETVs shall operate in the same aisle on the same set of rails and shall be oriented as shown on AF Drawing BDV806-01 with the operator cab of each ETV facing the interior end of the aisle. The ETVs shall comply with ASME B30.13 unless specified otherwise herein.

Dover AFB – Appendix A - Page 3

3.2. CHARACTERISTICS

3.2.1. OPERATING MODES

The ETVs shall have 4 operating modes called automatic mode, semi-automatic mode, manual mode, and maintenance mode. In automatic mode, the existing ICS shall control pallet and ETV movement with no operator intervention. In semi-automatic mode, the operator shall ride along operating the ETV from the ICS workstation installed in the operator cab. The ICS shall track the pallet movements while in semi-automatic mode. An ICS override key shall be required to activate manual mode. In manual mode, the operator shall utilize the ETV control consoles to operate the ETV without the use of any ICS components.

Maintenance mode is only available to qualified maintenance personnel and a key is required to enter this mode. In maintenance mode, many safety systems are not checked to provide enhanced maintenance capabilities and emergency operation of the

ETV.

3.2.2. ETV NETWORK CONNECTION

The existing ETV network connection shall be replaced with a newThe ETV network connection shall that provides a reliable communications signal with sufficient bandwidth for all data transfer without delaying other ETV operations. The ETV network connection shall operate while the ETV is in motion. The ETV network connection shall utilize a secure wireless device meeting the requirements of IEEE 802.11b or IEEE 802.11g operating at 2.4 GHz with minimum 128-bit encryption, an optical connection, a shielded transmitter/receiver unit, or other device that shall prevent stray electronic signals from leaking out and interfering with aircraft operations or other electronic signals and shall prevent the introduction of interference from background electronic signals. The frequency and power of wireless electronic signals may be limited by existing military and commercial users in the immediate area. The ETV network connection device shall be approved by the COTR.

3.2.3. CAPACITY

The load capacity shall be minimum 15,000 pounds on the ETV conveyor plus an operator in the operator cab. The ETV shall handle single 463L pallets. The ETV shall center and transfer any 463L pallet regardless of its location on any interfacing conveyor when transfer begins. The ETV shall meet all requirements specified herein and operate properly under all specified loading conditions.

Dover AFB – Appendix A - Page 4

3.2.4. ETV MOVEMENT

3.2.4.1. OPERATING SPEEDS

In automatic mode, the ETV horizontal operating speed shall be continuously variable from 30 +/- 5 feet per minute to 400 +/- 10 feet per minute. In all operating modes with an operator in the ETV cab, the ETV horizontal operating speed shall be continuously variable from 30 +/- 5 feet per minute to 200 +/- 10 feet per minute. In automatic mode, the lifting and lowering speed of the operator platform shall be continuously variable from 5 +/- 2 feet per minute to 60 +/- 5 feet per minute. In all operating modes with an operator in the ETV cab, the lifting and lowering speed of the operator platform shall be continuously variable from 5 +/- 2 feet per minute to 35 +/- 5 feet per minute. The ETV shall be capable of simultaneous horizontal and vertical travel in all operating modes.

3.2.4.2. TRAVEL CONSTRAINTS

The north ETV shall stop before entering the south ETV maintenance area and the south ETV shall stop before entering the north ETV maintenance area. The ETV maintenance area begins where the ETV would contact the maintenance stop. The south ETV shall stop before impacting the south end-of-aisle stop and the north maintenance stop. The north ETV shall stop before impacting the north end-of-aisle stop and the south maintenance stop.

3.2.4.2.1. HORIZONTAL SPEED CONSTRAINTS

Horizontal speed constraints shall apply during all ETV operational modes. When the north ETV is within 20 horizontal feet of the north end-of-aisle stop and moving horizontally toward the stop, ETV horizontal speed shall be limited to 60 +/- 5 feet per minute. When the south ETV is within 20 horizontal feet of the south end-of-aisle stop and moving horizontally toward the stop, ETV horizontal speed shall be limited to 60 +/- 5 feet per minute. When the north ETV is within 20 horizontal feet of the south maintenance stop and moving horizontally toward the stop, ETV horizontal speed shall be limited to 60 +/- 5 feet per minute. When the south ETV is within 20 horizontal feet of the north maintenance stop and moving horizontally toward the stop, ETV horizontal speed shall be limited to 60 +/- 5 feet per minute. When the ETV is within 20 horizontal feet of a stop, ETV horizontal speed in the direction away from the stop shall not be constrained due to proximity to the stop.

3.2.4.2.2. VERTICAL SPEED CONSTRAINTS

Dover AFB – Appendix A - Page 5

Vertical speed constraints shall apply during all ETV operational modes. When the ETV is within 1 vertical foot of the end of vertical travel and moving vertically toward the end of travel, vertical travel speed shall be limited to 15 +/- 3 feet per minute. When the ETV is within 1 vertical foot of the end of vertical travel and moving vertically away from the end of travel, ETV vertical speed in the direction away from the end of travel shall not be constrained.

3.2.4.2.3. ACCESS DURING MAINTENANCE

The north ETV shall be able to access all conveyors along the ETV aisle, except the SCs located in the south maintenance area and the first position north of the south maintenance area, when the south ETV is located in the south maintenance area. The south ETV shall be able to access all conveyors along the ETV aisle, except the SCs located in the north maintenance area and the first position south of the north maintenance area, when the north ETV is located in the north maintenance area. It shall not be necessary to enter maintenance mode to meet this requirement.

3.2.4.3. PROXIMITY CONSTRAINTS

Proximity sensors on each ETV as specified in 3.3.11. shall sense the distance between the two ETVs. The anti-collision system shall make use of redundant proximity sensors. The second sensor shall activate if the first sensor fails to activate and the ETVs are still approaching each other. The proximity constraints shall have no effect on ETV operation when the key switch to override the ETV proximity sensors is enabled.

3.2.4.3.1. PROXIMITY SLOW DOWN

When the ETVs are within 35 +/- 5 horizontal feet of each other and closing, the horizontal speed of an ETV moving toward the other ETV shall be limited to 60 +/- 5 feet per minute in the direction toward the other ETV. ETVs heading toward each other at full speed shall slow down to 60 +/- 5 feet per minute before the ETVs are within 15 feet of each other. Travel in the direction away from the other ETV shall not be constrained due to ETV proximity.

3.2.4.3.2. PROXIMITY STOP

When the ETVs are near each other and closing, an ETV moving horizontally toward the other ETV shall come to a full stop 4 +/- 2 feet from the other ETV under worst-case conditions. Worst-case conditions shall be both ETVs fully loaded and heading at each other at maximum speed. The stop shall be initiated a maximum of 15 feet from the other ETV since the ETV speed will

Dover AFB – Appendix A - Page 6 already be limited by the proximity slow down. After stopping, the ETV shall be able to move without resetting or restarting the ETV, although travel toward the other ETV shall remain constrained until the other ETV moves far enough away. Travel in the direction away from the other ETV shall not be constrained due to ETV proximity.

3.2.4.4. CYCLE TIME

3.2.4.4.1. AUTOMATIC MODE

Three separate aircraft load plans shall be released containing a total of 70 to 100 pallets. The time shall start when the first load plan is released and shall end when the last pallet of the last load plan is delivered through the overhead door of the PSE and the overhead door is completely closed. The average time for delivery of each pallet shall be lower than two minutes per pallet. Pallets shall be located in all regions within the system and may require hand-off between the ETVs. The staging docks the pallets are delivered to shall be recommended by the ICS system.

3.2.4.4.2. SEMI-AUTOMATIC AND MANUAL MODES

The ETV operating rate shall be defined by the following cycle:

This operation shall be accomplished in semi-automatic and manual modes in a total elapsed time of 170 seconds or less. Time shall start with the ETV at rest before the destination address is entered and shall end once the pallet stops are fully raised and the extractor is retracted following the second pallet transfer.

The anticipated workload is 80 cycles per ETV per 24-hour day, averaging 150 feet total horizontal travel, and that 90 percent of the cycles will be a raising and lowering cycle.

3.2.4.5. AUTOMATIC LEVELING

The lift system shall automatically adjust the operator platform height during pallet transfer to maintain the proper interface tolerance specified in 3.2.5. for pallet transfer. The transfer tolerances shall be maintained following repeated pallet

1. Start from a stationary position aligned with a SC on the lower level.

2. Travel 16 SCs (approximately 168 feet) horizontally, rise to the upper level, and stop.

3. Retrieve one fully loaded 463L pallet from the SC.

4. Travel 16 SCs (approximately 168 feet) horizontally, lower to the lower level, and stop.

5. Discharge the pallet to the SC.

Dover AFB – Appendix A - Page 7 transfers. The height adjustment shall occur without any action required from the operator. When automatic leveling, the ETV platform shall complete movement within two seconds of becoming out of tolerance. For audible and visual warning activation and safety interlock purposes, automatic leveling shall not be considered ETV travel. Resting pins shall not be used to maintain a level, stable conveyor interface.

3.2.4.6. ACCELERATION AND DECELERATION

Acceleration and deceleration shall be smooth and shall not cause slipping of the wheels under wet or dry conditions. The drive shall be designed to provide smooth starting and stopping throughout the operational range. There shall be no danger to personnel, the ETV, the load, and adjacent conveyors and structures when maximum braking is applied when the ETV is traveling at full speed at any elevation with any load.

3.2.4.7. CONTROLLED STOP

When a controlled stop is activated, the ETV shall decelerate from operating speed (up to full speed) to a complete stop in 15 feet or less if controlled by an operator in the ETV cab and in 25 feet or less if operating in automatic mode. A controlled stop shall not place stress on the ETV and shall not cause pallets on the ETV conveyor to shift or move. A controlled stop shall be smooth and safe and shall be capable of being repeated over the life of the equipment without harm to the ETV, including the brakes and crane rail.

3.2.4.8. EMERGENCY STOP

When an emergency stop is activated, the ETV shall decelerate from operating speed (up to full speed) to a complete stop in five feet or less if controlled by an operator in the ETV cab and in ten feet or less if operating in automatic mode. An emergency stop shall not cause pallets on the ETV conveyor to shift or move. If pallet transfer was occurring when the emergency stop was activated, both the ETV conveyor and the interfacing conveyor shall immediately stop. Power to all pallet stops shall be discontinued. The only action required to resume normal operations following an emergency stop shall be deactivating the cause of the emergency stop and resetting the ETV from either control console inside the operator cab or by maintenance personnel remotely resetting the ETV through the ICS. The emergency stop shall not damage the ETV, including the brakes and crane rail.

3.2.4.9. PSE DOOR OPEN TRAVEL INTERLOCK

Dover AFB – Appendix A - Page 8

The ETV shall not begin operation in automatic mode when any PSE door is not fully closed. If any PSE door is manually opened (not directed by the ICS) without a correct code being entered into the door security keypad or if any conveyor door does not fully close when directed by the ICS, the ETV shall come to a controlled stop and all conveyors operating within the PSE shall immediately stop as if an emergency stop had been activated.

3.2.4.10. CAB DOOR OPEN TRAVEL INTERLOCK

3.2.4.10.1. AUTOMATIC AND MAINTENANCE MODES

In automatic and maintenance modes the ETV cab door position shall have no impact on the operation of the ETV.

3.2.4.10.2. SEMI-AUTOMATIC AND MANUAL MODES

The ETV shall not travel and the ETV conveyor shall be inoperable while any ETV cab door is open. If a cab door is opened while the ETV is in motion, the ETV shall come to a controlled stop.

If a cab door is opened while the conveyor is in operation, the conveyor shall immediately stop as if an emergency stop had been activated.

3.2.4.11. SC STOP PUSH ROD RETRACTED TRAVEL INTERLOCK

The ETV shall not travel horizontally or vertically, other than automatic leveling, unless both SC push rods are fully retracted.

3.2.4.12. EXTRACTOR RETRACTED TRAVEL INTERLOCK

The ETV shall not travel horizontally or vertically, other than automatic leveling, unless both extractors are fully retracted.

3.2.4.13. OVERHEIGHT TRAVEL INTERLOCK

The ETV shall not travel horizontally or vertically, other than automatic leveling, with a pallet load taller than 120 inches on the ETV conveyor.

3.2.4.14. CONVEYOR OVERHANG TRAVEL INTERLOCK

Other than automatic leveling as specified in 3.2.4.5., the ETV shall not travel horizontally or vertically if objects overhang the sides of the ETV and extend beyond the ETV conveyor or if objects overhang either interfacing conveyor. If the ETV is in motion when a conveyor overhang sensor activates, an emergency stop shall occur.

3.2.4.15. AISLE OVERHANG TRAVEL INTERLOCK

Dover AFB – Appendix A - Page 9

The ETV shall not travel horizontally towards an obstruction if objects overhang the interfacing conveyors into the ETV aisle.

If the ETV is in motion when an aisle overhang sensor activates in the direction of travel, a controlled stop shall stop the ETV before the ETV impacts the obstruction. An emergency stop shall only occur if something is pushed into the aisle near the ETV when it is traveling toward the obstruction.

3.2.4.16. ETV SIDE DRIFT DURING TRAVEL

The ETV shall remain 2.5 +/- 1.5 inches from the interfacing conveyors, PSE structural members, and other fixed obstructions during travel. Guides or other methods to prevent excessive side drift during travel shall be provided.

3.2.5. ETV CONVEYOR INTERFACE REQUIREMENTS

The ETV shall physically, mechanically, and functionally receive 463L pallets from and discharge 463L pallets to all interfacing conveyors, either wide edge leading (WEL) and narrow edge leading (NEL). The ETV conveyor shall align with interfacing conveyors, with all loads specified in 3.2.3., within the following tolerances:

Horizontal positioning - maximum 0.25 inch difference Vertical positioning - maximum 0.25 inch difference

All interfaces shall be possible using only normal operating procedures in all operating modes except maintenance mode as specified herein. Extra steps or special procedures shall not be acceptable to meet interface requirements. Due to possible settling and shifting of the interfacing conveyor support structure, each individual interfacing conveyor shall have its own horizontal and vertical position programmed into each ETV.

3.2.6. ETV CONVEYOR

The conveying surface of the conveyor shall be at the same elevation +/- 0.12 inch across its entire length and width under all loading conditions. The conveyor shall interface with and transfer 463L pallets between the ETV and all SCs, LTCs, SDCs, and ALOC conveyors along the ETV aisle. The conveyor shall be capable or rotating pallets and transferring pallets perpendicular to the inbound/outbound direction, called side shift, for proper alignment between the side guides. Conveyor roller spacing shall be a maximum of 12 inches. The conveyor shall be configured as shown on Figure 1. The conveyor shall have its own motors. Powered-retractable pallet stops shall be provided at both ends of the conveyor. Ball transfer units shall be used where necessary to provide smooth pallet transfer and

Dover AFB – Appendix A - Page 10 prevent any point on a pallet from being more than 12 inches from a support roller or wheel. The conveyor shall allow for the manual transfer of pallets, including side shift and rotation, in accordance with 3.2.6.4. The ETV conveyor shall consist of the following.

3.2.6.1. RIGHT-ANGLE TRANSFER DECK

The right-angle transfer deck shall transfer 463L pallets in both the primary direction and in the secondary direction. Travel in the primary and secondary directions shall be accomplished without pallet rotation. Switching between transfer in the inbound/outbound direction and the perpendicular direction and vice-versa shall take a maximum of three seconds. The perimeter of the right-angle transfer deck shall have side guides except at interfaces with interfacing conveyors. For personnel safety, only wheels or rollers shall be used to convey 463L pallets. All wheels and rollers used to convey and support 463L pallets shall be powered. Only moving components coming in contact with 463L pallets shall be exposed or extend above the walkways, and all moving components not coming in contact with the 463L pallet shall be guarded. The design of the right-angle transfer deck shall allow for the manual transfer of pallets in the primary and secondary directions in accordance with 3.2.6.4.4. The design of the right-angle transfer deck shall be approved by the COTR prior to fabrication.

3.2.6.1.1. ETV PALLET ALIGNMENT

A method to align pallets for transfer onto aircraft shall be provided. Following alignment, the edges of pallets transferred onto SDCs shall be perpendicular and parallel with the side guides on the SDC. The edges of all pallets transferred onto the SDC shall be aligned within 1 inch of one another. The alignment shall be accomplished for all outbound pallets and shall be accomplished as quickly and easily as possible without causing damage or deformation to the pallet, pallet load, or ETV.

Dover AFB – Appendix A - Page 11

WALKWAY (TYP)

POWERED

STOP (TYP)

RETRACTABLE

END

HANDRAIL

INTERIOR

SLIDING CAB

DOOR (TYP)

CAB

48"

MINIMUM

12"

BUTTON (TYP)

CONTROL CONSOLE E-1

MINIMUM

EMERGENCY STOP

EXTERIOR

END

ICS WORKSTATION

CONVEYOR DECK

STAIRWAY (TYP)

24"

MINIMUM

FIGURE 1 - ETV

Not to Scale

3.2.6.2. TURNTABLE

The ETV conveyor shall rotate a pallet +90 degrees, -90 degrees, and 180 degrees as desired by the operator. The maximum time to rotate a fully-loaded 463L pallet 180 degrees shall be 12 seconds. The ETV pallet stops shall remain up during pallet rotation. Alignment lines on the conveyor deck shall indicate when a 463L pallet is aligned for transfer to an interfacing conveyor. Switching the conveyor between rotation and transfer in the inbound/outbound direction and vice-versa shall take a maximum of 3 seconds. The turntable shall rotate smoothly without hesitation or jerkiness. The turntable shall remain level within 0.25 inch throughout the entire rotation range. All motors, drives, wheels, sensors, and other turntable components requiring maintenance access shall be on the lower fixed frame that does not rotate. The rotating portion of the turntable shall be fixed at a center hub. and The turntable shall use a slewing type bearing or shall rest on wheels or rollers. Metal wheels shall not be used on a metal track. The wheels or rollers used to support the rotating portion of the turntable shall be a material that does not degrade over the expected life of the system, so levelness is maintained over time. The design of the turntable shall allow for manual pallet rotation as specified in

3.2.6.4.5. An electric slip ring or similar device approved by the COTR shall be used to transfer power and control information to and from the equipment installed on the turntable. The turntable shall have a positive mechanical lock at each 90 degree increment to prevent shifting during pallet transfer. The turntable shall align within 0.5 degrees at each 90 degree increment and shall remain aligned during and after pallet

Dover AFB – Appendix A - Page 12 transfer.

3.2.6.3. SIDE GUIDES

Side guides at the ends of the conveyor shall have an inside-to-inside guide width of 112 inches. Guide wheels shall be an acceptable alternative to side guides at conveyor interfaces.

The pallet stops and side guides shall be located such that a 463L pallet shall clear the pallet stops and side guides by 6 inches along all pallet edges when rotated. The side guides shall be a minimum of 152 inches at the widest location. The side guides shall not suffer damage when impacted by a pallet being rotated or when stopping a pallet during side-shift. Side guides shall have contact sensors built into the side opposite the cab to ensure the 463L pallet is square during side shift operations. The conveyor side guides shall provide a minimum restraining height of two inches above the conveying surface.

3.2.6.4. MANUAL OPERATION

The ETV conveyor shall permit manual transfer without the use of tools or disassembly of components. Manual transfer includes pallet stop retraction, powered roller disengagement, manually pushing a pallet, rotating a pallet, changing direction on the right-angle transfer deck, and all other activities necessary to move a pallet between the ETV conveyor and an interfacing conveyor. All manual transfer operations shall be possible without crawling beneath the ETV operator platform or leaning over the side of the ETV and shall be accomplished with a pallet in any position on the ETV conveyor. With all power, removed from the system, two people per 10,000 pounds of load plus one person to manually retract pallet stops shall be able to manually transfer a fully-loaded pallet between the ETV conveyor and all interfacing conveyors.

3.2.6.4.1. MANUAL OPERATION SAFETY

The system shall be designed to allow maintenance personnel to perform manual transfer on the ETV and ETV conveyor. Levers or foot pedals that are easily accessible shall be used to manually retract pallet stops and disengage rollers. Levers shall not present a tripping hazard or provide a snag point for cargo nets.

If removable levers are used, a storage position on the ETV shall be provided. The lever shall be placed for convenient access with pallets in place on the conveyor. Roller disengagement and manual retraction shall be accomplished with the conveyor supporting a 463L pallet in either the WEL and the NEL orientation in any position between the pallet stops and side guides. The manual operation mechanisms shall be easily and safely accessed, and the maintenance mechanic shall not be placed

Dover AFB – Appendix A - Page 13 in an unsafe or hazardous situation when operating the mechanism.

Note that manual pallet stop retraction shall take place during pallet transfer, so the maintenance mechanic must be able to manually retract the stops from a safe location. All manual operation mechanisms shall be clearly labeled as to their purpose and the result of placing the mechanism in each position.

Permanent, non-fading labels in clear type designed to last the life of the system shall be used to identify all manual operation devices. All manual operation mechanisms shall positively engage and disengage with lever or foot switch movement.

3.2.6.4.2. MANUAL PALLET STOP RETRACTION

The retractable pallet stops shall readily permit manual retraction. Manual pallet stop retraction mechanisms shall be spring loaded so the stop returns to the raised position automatically when the manual retraction ends. The force required to manually lower pallet stops shall not exceed 15 pounds. The ETV conveyor shall transfer pallets normally under power whether the pallet stops are manually retracted or retracted under power.

3.2.6.4.3. POWERED ROLLER DISENGAGEMENT

The power transmission system to the ETV conveyor drive rollers shall disengage such that all rollers rotate freely and manual pallet transfer is possible. The manual transfer shall be easily accomplished and shall not require more than 250 pounds of force per 10,000 pounds of load to start and maintain motion and shall not require the use of tools for leverage. While the power transmission system is disengaged, no additional safety hazards shall exist and no component shall be damaged if the conveyor is manually operated or if an attempt is made to operate the conveyor through normal means. The mechanism for powered roller disengagement shall remain in the selected position without further manual intervention. All pallet stops shall operate normally under power whether pallet loads are transferred manually or under power.

3.2.6.4.4. RIGHT-ANGLE TRANSFER MANUAL OPERATION

The ETV conveyor right-angle transfer deck shall permit manual operation in both the primary and secondary directions by maintenance personnel. Changing the conveyor between the primary direction and the secondary direction and vice-versa shall require only one maintenance person and shall be accomplished in maximum 45 seconds. No more than 30 pounds of force shall be required for manual right-angle transfer operation.

3.2.6.4.5. MANUAL PALLET ROTATION

Dover AFB – Appendix A - Page 14

The ETV conveyor turntable shall be capable of manual operation.

The turntable shall provide clearly labeled, safe, simple means to rotate pallets that can be easily accomplished for a sustained period of time by maintenance personnel. Removable handles or levers shall be placed at a convenient height if required for turntable rotation. No more than 40 pounds of force shall be required for manual turntable rotation. The design of the rotator shall comply with the following manual pallet rotation cycle time:

1. Start with the ETV deck empty and three 10,000 pound 463L pallets on an adjacent conveyor

2. Remove all power from the conveyors

3. Manually transfer the first pallet to the ETV conveyor

4. Manually rotate the first pallet 90 degrees

5. Manually transfer the first pallet off the ETV conveyor to an interfacing conveyor

6. Repeat steps 3 through 5 for pallets 2 and 3

The time to comply with the manual pallet transfer rotation cycle time shall not exceed 9 minutes with three persons (two to push the pallet and one to retract the stops). All safety, pallet transfer, conveyor interface, and manual operation requirements shall be met during this test.

3.2.7. PALLET MOVEMENT DURING TRAVEL

Pallet movement on the ETV conveyor shall occur only when the conveyor is activated. Pallets on the ETV conveyor shall not move due to ETV acceleration or deceleration, including emergency stops. Movement of pallets on the ETV conveyor shall not be possible during horizontal or vertical travel when controlled by an operator in the ETV cab. Simultaneous ETV travel and pallet movement shall be possible only in automatic mode.

3.2.8. HORIZONTAL AND VERTICAL DRIVE UNITS

Horizontal and vertical travel shall be accomplished through electric AC motors and variable frequency drives. The horizontal and vertical drive units shall position the ETV conveyor horizontally and vertically for pallet transfer without hunting, jogging, or swaying.

3.2.8.1. DRIVE MOTORS

The ETV shall be driven horizontally and vertically by a variable-speed squirrel-cage induction motor conforming to NEMA MG 1, Design Class B. The total motor starting torque shall be at least 200 percent of the rated torque. The starting current shall not exceed four times the rated current. The motor shall

Dover AFB – Appendix A - Page 15 provide constant torque at all speeds or an intelligent motor drive approved by the Contracting Officer’s Technical Representative (COTR) shall be used. The full load slip for induction motors shall not exceed five percent.

3.2.8.2. MOTOR DRIVES

3.2.8.2.1. MOTOR DRIVE CHARACTERISTICS

The motor drive shall be a variable frequency drive that varies the frequency of the applied voltage. The motor drive shall be digital. The motor drive shall be capable of reversing the motor while the motor is in operation. The motor drive shall provide counter-torque braking to decelerate high inertia loads and provide high braking torque. Motor inputs shall be ramped to prevent overloading during startup, reversing, and counter-torque braking. The drive unit shall display diagnostic messages to aid maintenance troubleshooting. A separate motor drive shall be provided for the horizontal motors and the vertical motors.

3.2.8.2.2. MOTOR DRIVE DIAGNOSTIC UNITS

A maintenance diagnostic unit including software and cabling that plugs into the drive to assist with troubleshooting and allows settings, operating history, and error logs to be downloaded and copied to a personal computer shall be provided for the horizontal drive and for the vertical drive. Two diagnostic units shall be provided if one unit does not interface with both drives.

3.2.8.3. BRAKING

Braking under normal operating conditions shall be accomplished by counter-torque braking the drive motors. Braking shall not endanger the operator or damage the load or the ETV.

3.2.8.4. HORIZONTAL DRIVE UNIT

3.2.8.4.1. DUAL HORIZONTAL DRIVE SYSTEM

Two or more horizontal drive systems shall be provided to enable operations at a reduced speed if one of the horizontal drive systems fails. For this requirement, a horizontal drive system shall include all drives, motors, controls, gearboxes, and other components required to receive control signals from the programmable logic controller (PLC) and transfer power to the drive wheel. If a horizontal drive system fails, maintenance personnel shall be able to disconnect it from the system in less than 10 60 minutes. Maintenance personnel shall be able to reconnect a horizontal drive system in less than 10 60 minutes.

Dover AFB – Appendix A - Page 16

The horizontal drive system shall operate at a minimum of 50 percent of the normal horizontal travel speed under a full load when powered by only one horizontal drive system and shall notify the operator of the reduced speed via a message on the display and the Inventory Control System’s (ICS) maintenance screen.

3.2.8.4.2. HORIZONTAL MECHANICAL BRAKE

The horizontal drive unit shall have a mechanical brake. The mechanical brake shall be a friction brake acting directly on the ETV horizontal drive motor shaft, any shaft positively connected to the horizontal drive motor shaft, or directly on the ETV crane rails. The mechanical brake shall automatically engage whenever the ETV ceases movement in the horizontal direction. After coming to rest, the mechanical brake shall not disengage until the proper inputs have been received to begin horizontal motion.

The mechanical brake shall engage and bring the ETV to an emergency stop if conditions requiring an emergency stop, including a complete power loss, occur. The mechanical brake shall be self-adjusting to maintain the proper pressure for braking action.

3.2.8.4.3. HORIZONTAL BRAKE RELEASES

A manual brake release shall be installed for the horizontal drive motors and the mechanical brake. The brake releases shall be a handle or lever that is permanently attached (i.e., tethered) to the ETV near the point of use. Operation of the brake releases shall be from the floor or an easy to access platform. The brake releases shall allow the ETV to be moved by warehouse tug, forklift, the other ETV, or no more than three people when fully loaded in the event of a complete power loss.

Once engaged, the brake releases shall remain engaged (brake released) without human intervention. The ETV shall not attempt to operate horizontally and a warning message shall appear on the display if power is available while the brakes are released. The brake release hardware and point of use shall be clearly labeled along with their operating positions.

3.2.8.5. VERTICAL DRIVE UNIT

Sensors and control logic shall prevent the operator platform from reaching its mechanical limits. The operator platform shall exhibit no vertical creep under any loading conditions when the lift control is in the neutral position. Rubber bumpers shall be provided at the travel limits. Guards shall be provided around the drum, rotating couplings, and other hazardous locations if accessible from ground level or from operator paths to and from the ETV cab.

Dover AFB – Appendix A - Page 17

3.2.8.5.1. DUAL VERTICAL LIFT MOTOR SYSTEM

Two or more vertical lift motor systems shall be provided to enable operations at a reduced speed if one of the vertical lift motor systems fails. For this requirement, a vertical lift motor system shall include all drives, motors, controls, gearboxes, and other components required to receive control signals from the programmable logic controller (PLC) and transfer power to the gearbox or hoist drum. If a vertical lift motor system fails, maintenance personnel shall be able to disconnect it from the system in less than 10 60 minutes. Maintenance personnel shall be able to reconnect a vertical lift motor system in less than 10 60 minutes. The lift system shall operate at a minimum of 50 percent of the normal vertical travel speed under a full load when powered by only one vertical lift motor system and shall notify the operator of the reduced speed via a message on the display.

3.2.8.5.2. OPERATOR PLATFORM

The operator platform shall hold the operator cab, the ETV conveyor and a maintenance platform, located above the ETV conveyor. The operator platform shall raise and lower to align the ETV conveyor with all interfacing conveyors and to align the maintenance platform with the upper maintenance platform located on the mask.

3.2.8.5.3. OPERATOR PLATFORM LIFT CABLES

Lift cables, each with sufficient strength to support all required loads, shall be provided on both ends of the operator platform. The short lift cable shall run from the drum through two sheaves at the top of the mast and two sheaves on the operator platform before being tied off at the top of the mast.

The long cable shall follow the same pattern as the short cable except it shall run though a sheave at the top of the mast nearest the drum. The fleet angle shall not exceed one degree without approval from the COTR.

3.2.8.5.3.1. LIFT CABLES LOAD CELLS

Each lift cable shall attach to a load cell. The load cells shall continuously monitor the load on each cable. Live readings for the load cells shall be transferred to the existing ICS for monitoring by maintenance personnel. A history of the load cell reading shall be maintained by the ICS. A no load reading shall trigger the safety grabs to engage.

3.2.8.5.4. OPERATOR PLATFORM STABILIZATION CABLES

R2,R3

Dover AFB – Appendix A - Page 18

Operator platform stabilization cables shall be provided so that in the event of a lift cable failure, the operator platform does not result in either end of the operator platform being unsupported or falling. This requirement shall be met by dual cables that are anchored on each mast, above the fourth level of storage at one end and routed through two sheaves, mounted to the bottom of the operator platform on each end, before being tied off on the ETV lower frame. This chair configuration of the two cables shall be designed to maintain platform levelness. Under normal conditions the platform stabilization cables carry no load, but shall be designed to support the weight of a fully loaded operator platform.

3.2.8.5.5. LIFT CABLE DESIGN

The contractor shall certify, via calculations, that all lift cables have a safety factor of 6 and are designed for a 5-year service life in this application. All wire rope cables shall be pressure lubricated. All cables provided shall show wear first on the outside before wearing on the inside.

3.2.8.5.6. VERTICAL SAFETY GRABS

Safety grabs shall be integrally designed into the lift system such that any loss of vertical holding force shall lock the operator platform to the support structure preventing an uncontrolled fall of the operator platform with any load up to the maximum capacity. In case of a complete power loss, the lift device, under any loading condition, shall stop and remain in position. Safety devices shall prevent an over speed condition.

The safety grabs shall be mechanically activated for safety in the event of power loss, but shall also be activated by the PLC under certain conditions. The safety grabs shall be capable of being used a minimum of 100 times without reducing their effectiveness, affecting ETV performance, or requiring components to be replaced. The design of the safety grabs shall permit testing during the quality conformance test and annually thereafter to verify their effectiveness.

3.2.8.5.7. OPERATOR PLATFORM FALL PREVENTION

The design of the lift system shall be inherently fail-safe to prevent an uncontrolled fall of the operator platform if any component has failed. As a minimum, the following additional safety measures shall be incorporated into the lift system:

slack cable sensors, adjustable torque limit on the lift motors, lower and upper guide wheels on each end of the operator platform, sensors to prevent over travel of the lift motors, mechanical retainers to keep the lift cable in the intended pathways, steel sheaves and drum, automatic shutoff of the lift

Dover AFB – Appendix A - Page 19 motors at the lower limit of travel, PLC activation of the safety grabs if the measured position or velocity is inconsistent with the expected position or velocity, etc.

3.2.8.5.8. LIFT MOTOR AND GEARBOX REPLACEMENT

ETV design shall permit lift motor and gearbox removal and replacement by 10k forklifts while the ETV is parked in the ETV maintenance area. Additional equipment such as a hoist mounted to structural members near the ceiling shall be provided if necessary to meet this requirement.

3.2.8.5.9. EMERGENCY MANUAL LOWERING

The vertical drive unit shall allow the operator platform to be safely lowered from any elevation to the lower level with any specified load without external power. Manual lowering shall be possible by one person in less than fifteen minutes. The person shall stand on the ground by the ETV or in a safe location on the ETV while lowering the operator platform. Personnel shall not stand or reach beneath the operator platform to accomplish manual lowering. Special tools or other nonstandard equipment needed for manual lowering shall be permanently attached (i.e., tethered) to the ETV near the point where the manual lowering takes place. The manual lowering mechanism shall be labeled to indicate the function and operating positions. No special actions such as resetting the vertical positioning system shall be required after manually lowering and returning to normal powered operation. Operator platform positioning stops shall be provided if necessary to prevent lowering of the platform below the elevation of the lower level interfacing conveyors.

3.2.8.5.10. OPERATOR PLATFORM SAFETY PINS

Two sets of maintenance pins shall be mounted on each ETV mast, one for…