1、Comments, suggestions, or questions on this document should be addressed to WR-ALC/LGEC, 480 Richard Ray Blvd. Suite 200, Robins AFB, GA 31098-1640 or emailed to Priest.Blackstockrobins.af.mil. Since contact information can change, you may want to verify the currency of this address information usin
2、g the ASSIST Online database at http:/assist.daps.dla.mil FSC 1740 A-A-59210C 31 July 2006 Superceding A-A-59210B 26 May 2004 COMMERCIAL ITEM DESCRIPTION TRACTOR, AIRCRAFT TOWING, MB-4 The General Services Administration has authorized the use of this commercial item description by all federal agenc
3、ies. 1. SCOPE. This Commercial Item Description (CID) covers the requirements for one type of MB-4 aircraft towing tractor, hereafter referred to as tow tractor. The tow tractor is capable of towing trailers up to 80,000 pounds, and military aircraft up to 175,000 pounds on dry level concrete. 2. SA
4、LIENT CHARACTERISTICS. Failure of the tow tractor to meet the salient characteristics of this CID shall be cause for rejection of the tow tractor. The tow tractor shall be free from faulty construction and any defect that affects appearance, serviceability, and durability. The tow tractor shall be r
5、epresentative of the quality and workmanship found in tow tractors offered for new commercial sale. 2.1 Gross vehicle weight (GVW). The tow tractor shall have a minimum GVW of 19,000 pounds. 2.2 Overall dimensions. Overall dimensions shall be the minimum consistent with the operational performance a
6、nd the design constraints necessary to achieve the specified performance. Overall dimensions shall not exceed: Length: 200 inches without couplers Width: 100 inches without mirrors Height: 100 inches 2.3 Drawbar pull (DBP). The tow tractor shall have a minimum DBP of 16,000 pounds on dry level concr
7、ete. INCH POUND Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A-A-59210C 22.4 Power train. The tow tractor shall have a commercially available, liquid cooled, turbocharged diesel engine of not less than six cylinders and power train sufficient to d
8、evelop the required drawbar pull and obtain the required tow tractor speeds. Power train components shall have adequate torque and power ratings for the imposed torque and power. The tow tractor power train shall possess sufficient cooling capacity to perform continuous maximum performance towing in
9、 high ambient temperatures of +125 degrees F without exceeding the manufacturers maximum allowable temperatures on the individual power train components. Any requirements for towing in high ambient temperatures (recommended coolant ratios, oil types and viscosities, etc., for various temperature ran
10、ges) shall appear in the Technical Order (TO). The diesel engine shall operate satisfactorily when using Jet A-1 (JP-8) fuel. Power train shall feature a standard (type C) winterization package that is good for starting down to minus 20F, or when specified (see 6.2 c), a heavy-duty (type A) winteriz
11、ation package good for storage down to minus 65F and starting to minus 40F. Winterization package components with external power requirements shall be compatible with 110VAC/20A circuitry. For each winterization package, a breakdown of the winterization components and requirements (recommended coola
12、nt ratios, oil types and viscosities, etc., for the various temperature ranges) shall appear in the TO. The tow tractor shall meet applicable 50-state exhaust and evaporative emissions standards in effect at the time of vehicle manufacture. The tow tractor shall include an anti-restart, as well as a
13、 neutral safety start feature. Engine shall have an automatic engine shutdown system for high coolant temperature and low oil pressure. Transmission shall be of the power-shift type, with an integral, limited-slip, inter-axle differential. Maximum allowable transmission temperature during all operat
14、ions shall not exceed 260 degrees F. Axles shall be planetary-drive/steer axles. 2.5 Driveline and steering. The tow tractor shall have four-wheel drive, and two-wheel and four-wheel power steering. Four-wheel steering shall feature both crab and coordinated steering. The selection of the steering m
15、ode shall be accomplished by the movement of a one-hand-operated lever or switch. When switching from the crab or coordinated four-wheel mode of steering to the two-wheel mode of steering, the rear wheels shall center automatically (wheels perpendicular to axle) as the steering wheel is rotated to t
16、he wheel center, without additional operator input or adjustment. The tow tractor shall have a maximum wall-to-wall turning radius of 17 feet or less while in four-wheel coordinated steering mode. Wheel-wells shall be designed so that tire chains may be used without interference. 2.6 Electro-magneti
17、c interference (EMI). The tow tractor shall comply with EMI requirements of MIL-STD-461 for Radiated Emission per RE102, Radiated Susceptibility per RS103, and Conducted Susceptibility per CS114, CS115, and CS116 for Air Force ground equipment. 2.7 Mobility. The tow tractor shall be capable of trave
18、ling a minimum of 25 miles per hour (MPH) forward and 2.5 MPH in reverse on flat asphalt or concrete surfaces without a trailing load. Additionally, the tow tractor shall be capable of towing an 80,000 pound trailer on a 4% grade at a minimum of 8 MPH on asphalt or concrete surfaces. An externally-m
19、ounted back-up warning alarm shall be included in the reverse lights circuit. 2.8 Suspension. On occasion the tow tractor will leave the flight lines and roads within the perimeter of the base, and enter both paved and unpaved surfaces. The angle of each surface relative to the other can differ. The
20、 tow tractor shall have a suspension that will allow for Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A-A-59210C 3articulation of one or both of the tow tractors axles, so that an axles position relative to the other will allow for four-wheel cont
21、act with the normal working surfaces found in the above described conditions. 2.9 Wheels and tires. The tow tractor shall be equipped with steel disc wheels and tubeless steel belted radial tires with an appropriate tread pattern. The valve stems may be rubber or metal, but the valve stem caps shall
22、 be vinyl or plastic. The wheels and tires shall be in accordance with (IAW) the Tire and Rim Association recommendations for this application. All wheels and tires shall be uniform. Tire inflation pressures shall be noted on all wheel well openings, and shall be in accordance with Air Force Technic
23、al Order (T.O.) 36-1-191. If tire loads and tire inflation pressures that exceed the specifications on the tire sidewall markings are required, a copy of the application approval from the tire manufacturer shall be added in the Technical Order. 2.10 Braking system. The tow tractor shall feature a fo
24、ur-wheel, hydraulically operated braking system with power assist. If an air system is used as the power assist (air-over-hydraulic brakes), cab instrumentation shall include an air pressure gauge and a low-pressure indicator with buzzer and/or warning light (see 2.15). When an air system is specifi
25、ed for trailer towing (see 6.2 d), the air system shall be used as the power assist for the braking system (air-over-hydraulic brakes). Air-over-hydraulic braking systems shall be activated by a brake foot pedal which modulates air to the braking system. The brakes shall be capable of stopping a 175
26、,000 pound towed load on a dry level asphalt or concrete surface from 5 MPH in no more than 18 feet. 2.11 Parking brake. The tow tractor shall be equipped with a mechanically actuated disc type parking brake. A lockout system shall be provided so that the tow tractor will shut down when the parking
27、brake is on and the tow tractor is placed in forward or reverse gear. The lockout system shall also include a cab-mounted warning light. The tow tractor parking brake shall be capable of holding the tow tractor and a fully loaded MHU-141 trailer on an 11.5 degree incline, headed either up or down, w
28、ithout the trailers parking brake engaged. The MHU-141 trailer has a maximum loaded weight of 8,400 pounds and a manual parking brake located on the trailer. 2.12 Air system. When specified (see 6.2 d), the tow tractor shall have an air system for towing the Air Forces four-wheel MHU-196 and MHU-204
29、 trailers with air brakes. The air system shall be an over-the-road commercial truck/tractor design to include primary and secondary reservoir tanks, a wet tank, heated and automatic drain valves, automotive compressor, dryer, trailer protection valve, low-pressure indicator, service and emergency g
30、lad hands, glad hand covers with lanyards, etc. The glad hands shall be in accordance with SAE J318, and shall be polarized and identified as “service” and “emergency”. Compressor sizing shall be in accordance with compressor manufacturers recommendations for off-highway use. Components of the air s
31、ystem that are sensitive to the elements (rain water, road water, ice build-up, road grit, etc.) and installed in positions on the tow tractor that are vulnerable to those elements shall be covered or shielded to prevent the premature failure of those components over time or during service. The tow
32、tractors air system shall be activated by a brake foot pedal which modulates air to the braking system and supplies air to the trailer with sufficient speed and volume so as to work the tow tractor and trailer brakes simultaneously. The tow tractor/trailer combination shall stop straight in a 12 foo
33、t wide corridor. The tow tractor shall not exhibit Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A-A-59210C 4tendencies to tip, tilt, yaw, sway, skid, bounce, or jackknife under maximum performance maneuvers in such a way that safe control of the t
34、railer payload is in jeopardy. The MHU-196/204 trailers have 1/4” ID service brake air lines and 3/8” ID parking brake air lines. The trailers have air brake chambers and drum brakes on each wheel, and a complete self-contained air control system including a supply reservoir fed from the tractors em
35、ergency glad hand. The trailers service brakes are actuated from the trailers own air supply by air relays that get their signal from the tractor service glad hand. The trailers air relays are located adjacent to the trailers front wheels. The distance from the rear of the tow tractor to first set o
36、f wheels on the trailer is approximately 10 feet, and from the first set of wheels to the second set of wheels is approximately 30 feet. The trailers braking system working pressure is 90 psi. The fully loaded trailer has a maximum deceleration rate not exceeding 20 ft/sec at 90 psi. Prior tow tract
37、or and trailer testing has revealed an actual deceleration rate of approximately 1719 ft/sec for the MHU-196/204 trailer. The MHU-196 trailer is towed at 10 mph loaded, and 20 mph unloaded. The MHU-204 trailer is towed at 10 mph loaded or unloaded. The maximum weight of the fully loaded MHU-196/204
38、trailer is 80,000 pounds. When the air system is specified, a decal shall be included on the front of the vehicle near the pintle hook locations that states, “DO NOT USE THE FRONT PINTLE POSITIONS TO TOW MHU-196/204 TRAILERS”. 2.13 Electrical system. The tow tractor shall be equipped with a 12V elec
39、trical system. The battery(ies) shall be maintenance free. All external chassis wiring shall incorporate weather-proof connections and terminations. Exceptions to this are under-hood terminal strips and electrical posts that are protected from the elements. Any wire splicing (typically resulting fro
40、m special-request options) shall incorporate a mechanically-crimped connector, solder and heat-shrink tubing. All crimped-on wire components (i.e. Weatherpac or Metri-pac style connectors) shall be installed using the appropriate crimping tool for the application. All wiring shall be of the appropri
41、ate gauge for the amperage the circuit is drawing and/or protected to. Batteries shall be accessible for daily inspection without the need for hand tools. 2.14 Frame structure. The tow tractor shall have an all-welded, one-piece frame structure. 2.15 Cab design. The tow tractor shall be equipped wit
42、h a center-mounted, enclosed, two-man cab. Interior cab sound level shall not exceed 84 dB (A) with doors and windows closed. Doors shall be constructed of rigid materials. The first entrance step to the cab shall not exceed 18 inches in height from the ground. If there is more than one step to the
43、cab (including the cab floor), then each step shall be offset out from the next step up by at least 3 inches. Cab instrumentation shall be standard commercial installation to include an hour meter, odometer, tachometer, speedometer, voltmeter, engine oil pressure gauge, engine coolant temperature ga
44、uge, transmission temperature gauge, and a fuel level gauge. When an air system is used as the power assist for the braking system (see 2.10), or when an air system for trailer towing is specified (see 6.2 d), cab instrumentation shall include an air pressure gauge and a low-pressure indicator with
45、buzzer and/or warning light. When specified (see 6.2 g), the tow tractor shall have an Air Conditioning system. The tow tractor cab shall be equipped with wipers, a windshield washer, driver and passenger-door rear-view mirrors, windshield-area rear-view mirror, visors, heater/defroster, ventilating
46、 fan, interior dome light, seat belts, and other equipment as found in standard commercial offerings. The cab shall feature a rear sliding window and a 12V power Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-A-A-59210C 5outlet (cigarette lighter ty
47、pe). The drivers and passengers seats shall incorporate a scissors-type suspension for driver and passenger comfort. 2.16 Lighting. The tow tractor lighting shall be equivalent to the standard commercial offering to include a rear adjustable aim floodlight, parking lights, head lights (high and low
48、beam), brake lights, turn signals, hazard lights, and reverse lights. A flashing amber beacon light shall be mounted on the cab roof on the tow tractors centerline. The rear adjustable aim floodlight, of not less than 3000 candlepower, shall be mounted on the tow tractor so that the following areas
49、are illuminated: the rear working area behind the cab, the rear coupling positions, and a reflective, vertical indicator stripe measuring approximately 1” x 8” located on the towed MHU-196/204 trailer; the stripe is located at a horizontal distance of 10 feet behind the pintle hook, and a vertical distance of 22” to 210” from the ground. When specified (see 6.2 f), the tow tractor shall be equipped with an adjustable spotlight, capable of illuminating 180 d
