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TFC/IW, total fuel consumption divided by inertia weight is reported with other engineering variables for recent EPA data for industry passenger cars and truck. TFC/IW is used in comparisons between gasoline and diesel engines, 49 States and California, passenger cars and trucks. The California fuel economy penalty due to more stringent emissions standards is discussed. The relationship between TFC/IW and ton miles per gallon is shown. Special attention is focused on 4 cylinder gasoline powered vehicles in 49 States passenger car fleet. The use of TFC/IW to answer the question, ‘What Changed?’ when comparing the fuel economies of two fleets is described.

A survey of the in-service fuel consumption of passenger vehicles and derivatives in the Australian fleet was carried out in 1984-85. Seven hundred and four owners across Australia took part in the survey. Vehicle owners reported by questionnaire the amount of fuel used during four tank fills of normal operation, the distance travelled, and other details of the operating circumstances. The survey shows a clear downward trend in the fuel consumption of the Australian passenger fleet. The data also provides comparisons of actual fuel consumption obtained on the road, with laboratory derived values for fuel consumption. Vehicles in a sub-set of 40 were fitted with fuel flow meters during the survey and tested to Australian Standard 2077 for fuel consumption. The questionnaire method is shown to be a valid and accurate technique for determining in-service fuel consumption.

Diesel propulsion of commercial vessels burning “heavy fuel” on the Great Lakes, for one operator, has come about by an evolution beginning in 1951 and culminating in 1, 000′ LOA vessels burning intermediate fuels, pre-blended using residual and distillate mixtures, in large medium speed, heavy duty diesel engines.

In recent years there has been increasing interest in quantifying the emissions from aircraft in order to generate inventories of emissions for climate models, technology and scenario studies, and inventories of emissions for airline fleets typically presented in environmental reports. The preferred method for calculating aircraft engine emissions of NOx, HC, and CO is the proprietary “P3T3” method. This method relies on proprietary airplane and engine performance models along with proprietary engine emissions characterizations. In response and in order to provide a transparent method for calculating aircraft engine emissions non proprietary fuel flow based methods 1,2,3 have been developed. This paper presents derivation, updates, and clarifications of the fuel flow method methodology known as “Fuel Flow Method 2”.

With the increase in demand for energy sustainability projects over the last few years, the Brazilian commercial vehicle industry was guided to develop projects based on ESG policies. Aligned with this need, an initiative that ended up becoming a reality was the “e-Sys” electrification solution, by the company Suspensys. This solution includes a power source (battery), an e-powertrain (motors, inverters and drive axle) and an intelligent control system (VCU with embedded code and sensors). The main motivational drive was the hybridization of semi-trailers, in order to generate a reduction in fuel consumption in cargo transport in Brazil, in addition to the consequent reduction in the emission of particles into the environment and promoting the safety of the operation. It was also adopted, as a premise of the project, that the electrification system was totally independent of the truck’s electronic system (stand alone system), in order to facilitate the operation of the fleet owner.

The trend towards renewable energy sources will continue under the pre-amble of greenhouse gas (GHG) emission reduction targets. The main question is how to harvest and store renewable energy properly. The challenge of intermittency of the renewable energy resources make the supply less predictable compared to the traditional energy sources. Chemical energy carriers like hydrogen and synthetic fuels (e-Fuels) seem to be at least a part of the solution for storing renewable energy. The usage of e-Fuels in the existing ICE-powered vehicle fleet has a big lever arm to reduce the GHG emissions of the transport sector in the short- and medium term. The paper covers the whole well-to-wheel (WtW) pathway by discussing the e-Fuel production from renewable sources, the storage and the usage in the vehicle. It will be summarized by scenarios on the impact of e-Fuel to the WtW CO2 fleet emissions.

The mutual aerodynamic influence of road vehicles in close proximity is known to alter significantly the drag performance of the vehicles. This paper presents an extended analysis from a study of two open-access road-vehicle shapes (a DrivAer Notchback model and an AeroSUV Estateback model) in close lateral proximity with each other, or with other vehicle shapes. Wind-tunnel measurements were conducted for a yaw-angle range of ±10°, for lateral distances representing 75%, 100%, and 125% of a typical highway lane spacing, and for longitudinal distances up to 2 vehicle lengths forward and back. The results of a previous analysis of the data, which examined aerodynamic force measurements only, showed changes in drag coefficient of ±20% or more depending on the relative locations and wind conditions. In this paper, the force-coefficient results reexamined, and surface-pressure measurements are introduced to investigate the sources of the performance changes.

The use of devices to reduce aerodynamic drag on large trailers and save fuel in long-haul, over-the-road freight operations has spurred innovation and prompted some trucking fleets to use them in combinations to achieve even greater gains in fuel-efficiency. This paper examines aerodynamic performance and potential drag reduction benefits of using trailer aerodynamic components in combinations based upon wind tunnel test data. Representations of SmartWay-verified trailer aerodynamic components were tested on a one-eighth scale model of a class 8 sleeper tractor and a fifty three foot, van trailer model. The open-jet wind tunnel employed a rolling floor to reduce floor boundary layer interference. The drag impacts of aerodynamic packages are evaluated for both van and refrigerated trailers. Additionally, the interactions between individual aerodynamic devices is investigated.

Dragfoiler II, an effective and practical add-on aerodynamic drag reducing system for tractor-trailers, has been developed. Wind tunnel tests with 1/16- and 1/7-scale tractor-trailer models were used to determine empirical design guidelines for the Dragfoiler II's side elevation and planform shapes. Optimum designs for various combinations of tractor roof height and length, trailer height, and tractor-to-trailer gap length gave zero-yaw drag reductions between 30 and 35%. At a yaw angle of 10°, the percentage drag reductions were about half those at 0°. Off-design performance and the effects of trailer side-edge geometry were investigated. Several full-scale Dragfoiler II's are currently undergoing proving ground and commercial fleet evaluation tests.

Through this work, Wind River and Airbiquity look to enable secure and intelligent software updates and data management for these vehicles through over-the-air (OTA) programming technology. The work may also lead to similar solutions for traditional aerospace and unmanned aircraft system (UAS) industries.

Hybrid Electric (HE) Propulsion will be part of the Army's Transformation, not because it's easy but because it makes FCS a threat to The Threat. A successful integration of an HE Propulsion system provides significant advantages in individual vehicle performance and potential. It will provide a ground force significant advantages by reducing its logistic footprint. However, a successful integration of an HE Propulsion system must overcome significant technology challenges, particularly in energy storage and energy conversion. The U.S. Army is addressing these challenges through numerous technology developments and evaluation programs.

The wide base light truck tire is a new low profile, wide rim tire concept, which significantly improves vehicle performance. The wide base tire also simplifies and standardizes tire and rim usage, making obsolete the variety of tire sizes, types, and rim styles previously available.

TIRE matching is not a simple matter, says Mr. Place, for a good program of matching on one operation may not give as good results, relatively, on another. For this reason, he asserts that it is impossible to make one blanket recommendation that will give the best overall results on all fleet operations. Thus, he confines himself to describing what takes place during the use of dual tires, and discusses certain service expedients that operators may try under close observation.

AID for the fleet operator is contained in this paper, which presents basic information to help him get the best from his fuel, whether he uses gasoline or diesel fuel, from his lubricating oil, whether he uses the regular or heavy duty, and from his gear lubricants.

In the past decade, the space shuttle has been the key factor for the United States manned space exploration. In fact the space shuttle is the only means in which the United States government can send humans into space. However, the space shuttle's life-expectancy is due to expire around the year 2005. In preparation for the end of the space shuttle era, we, as a country, must decide what type of future space vehicle is appropriate to accomplish our future national goals in space. There are many public policy alternatives to the question: ‘What will replace the space shuttle?’ First, the United States could try a conservative approach to space exploration by developing and using an unmanned vehicle. Second, the government could opt for utility by developing a mixed fleet of launch vehicles. Third, the United States could try to modify and update the current space shuttles with new technology.

UNJUST legislation in the middle of the 19th Century retarded the introduction of road locomotion. The Motor Carrier Act, 1935, calls for extreme regulation, patterned after railroad control. The many differences between the two services prevent like treatment without strangling the virtues and economies of motor transportation. The difficulty of attempting to regulate it is due to the fact that most “fleets” consist of one truck which is owner-operated and only 9 per cent of all trucks are of the For-Hire type. The present predicament of the railroads is due chiefly to general conditions brought about by the depression, the result of over-regulation, and in not keeping in step with the advancement of other industries. The passenger automobile accounts for some loss of revenue, but its use is taken for granted. It therefore seems strange that the other forms of rubber-tired vehicle are not accepted in the march of progress.

THIS paper is a non-technical review of an up-to-date survey of the lines of tires needed in all types and classes of fleet operation. To understand better how to get the best results from their operations, operators must know the proper type of tire to use. The author first describes and catalogs the principle forms of tire failures, then reviews the characteristics of the fundamental lines of tires available at the present time. Next, an attempt is made to classify the different types of fleet operation so that definite recommendations can be made as to the most appropriate tire equipment for these vehicles. The types of tire trouble most commonly encountered in each group are brought out with suggestions on how to avoid them. This part is followed by a section giving advice on the care of tires. The paper concludes with a brief survey of worthwhile facts about repairs and retreading. An appendix contains the load-inflation tables which are most widely used.

Electronic data processing has been used as a management tool in vehicle replacement, inventory control, and vehicle maintenance in a large fleet. It also shows promise in vehicle maintenance scheduling. Data processing can point out problem vehicles, and predict maintenance cost in the future so vehicles can be replaced at the most economical cost.

This paper shows how the quantity demanded, viewed as an independent variable, interacts with customer values, producer costs and constraints. Failure to analyze Demand as Independent Variable (pronounced “Dave”) increases the chances that new programs will not launch, or once started, will fail. All producers in all markets face demand curves that describe their customers' reaction to price changes. Aggregate market demand curves show how buyers react to price changes within broad product sets, while product demand curves show buyer responses to a specific item. Demand curves relate quantities sold relative to their prices. In several military, transit and fleet cases, minimum quantity requirements form upper price boundaries along demand curves. Allowing prices to go so high that buying authorities cannot acquire the required numbers of units likely means that there may not be sufficient resources to form systems that can accomplish the buyers' goals.