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4.0 TECHNOLOGY STATUS AND DEVELOPMENTS

4.1 Status of Bus Manufacturers

Currently, there are six manufacturersin North America that are offering heavy-duty, low-floor buses to the transit market.Some of the technical characteristics of the40-foot, low-floor models by manufacturerare given in Table 4.1. The sizes of low-floorbuses that are currently offered or are underdevelopment for each manufacturer areidentified in Table 4.2. As can be seen inTable 4.2, all manufacturers have a 40-footmodel, and four have (or plan to have) a 35-foot model. The various propulsion and fueloptions that are available from eachmanufacturer are identified in Tables 4.3 and4.4.

4.2 Developments in Technology

There are several projects that couldlead to significant advances in body andpropulsion technologies that are applicable tofuture low-floor bus developments. TheAdvance Technology Transit Bus (ATTB)program was initiated in 1992 with theobjective of developing a lightweight, low-floor, low-emission transit bus. There are two

programs to develop a fuel cell powered bus,one of which is integrated in a low-floor bus.There are several hybrid electric propulsionsystem projects that are expected to reach theproduction stage in the near future. Each ofthese programs is discussed in the followingsections. The last two subsections ondevelopments in technology discuss newapproaches under development in Europe.The first discusses innovative approaches towheelchair securement involving "rear facingprotected position" designs that are beingadopted in Europe. The last subsectiondiscusses level boarding with low-floorbuses, and some of the experiences with levelboarding in Europe.

4.2.1 Advanced Technology Transit Bus

The ATTB is a major Federal projectto develop a 40-foot transit bus that meetsFederal requirements for axle loads,emissions, and accessibility, a maximum unitprice of $300,000 (1992 dollars), lowoperating costs, and can accommodate 43seated and 29 standee passengers. A layoutof an example seating arrangement is givenin Figure 4.1.

Figure 4.1 Example Seating Layout for the ATTB

Source: Reference 34

Table 4.1 Technical Characteristics of 40-Foot, Low-Floor Buses

Source: Bus Manufacturers

(a) With roof mounted air conditioning unit.(b) Over access hatch.(c) Entrance height with standard profile tires is 15 inches, and the exit height is 16.25 inches.(d) Entrance and exit heights will depend on the tires used.(e) Height of exit behind the rear axle is 14.5 inches.(f) With four rear-facing seats.

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Table 4.2 Size of Heavy-Duty, Low-Floor Buses Offered by Manufacturers

Source: Bus Manufacturers

(a) The 35-foot model is under development.

Table 4.3 Propulsion OptionsOffered by Manufacturers

Source: Bus Manufacturers

(a) Planned or under development.

Table 4.4 Fuel OptionsOffered by Manufacturers

Source: Bus Manufacturers

(a) Compressed natural gas.(b) Liquefied natural gas.

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The ATTB environmental design goals arethe California Air Resources Board (CARB)Low Emission Vehicle (LEV) requirementsfor urban buses. The program calls for thedesign and fabrication of six prototypes.Field testing is scheduled through 1998. Thephysical characteristics of the ATTB aregiven in Table 4.5.

The first bus is an engineering testbed that is being used to evaluate varioussubsystems and to validate the designapproach. The second bus incorporateddesign improvements developed with the firstunit, and is the durability test bed. Busnumber 2 is currently being tested at theAltoona Bus Testing Center. The remainingthree units will be used for demonstrationsand revenue service tests at several citiesthroughout the U.S.

4.2.2 Fuel Cell Developments

There are two efforts underway topower a transit bus with fuel celltechnology. One is the Federal TransitAdministration (FTA) Fuel Cell Transit BusProgram, and the other is the Ballard FuelCell which has been integrated in an NFILD40L bus. While the test bed used in theFTA program is a high-floor bus, ifsuccessful the technology could be used in alow-floor bus. The incentives forconsidering fuel cell technology are apollution free bus service, use of a non-fossilfuel, and an increase in range over batterytechnologies.

The FTA program is a joint programwith the Department of Energy (DOE), and ismanaged by the Georgetown University. Theprogram objective is to integrate aphosphoric acid fuel cell in a 40-foot transitbus (RTS). Methanol is fed to a reformer

which produces the hydrogen gas used bythe phosphoric acid fuel cell to produceelectric energy. A prototype is to bedelivered in the Summer of 1998 for testsand evaluation.

Ballard Power Systems has installedfuel cell engines in seven NFIL D40L buses.Three of these buses have been sold to theCTA and three to BC Transit Vancouver.The buses were delivered in 1997. TheBallard fuel cell uses hydrogen gas stored inhigh pressure cylinders, similar to thoseused for CNG storage. The hydrogen gas isfed into a Proton Exchange Membrane(PEM) fuel cell which through anelectrochemical process produces electricpower and water vapor. The CTA fuel cellbuses will be placed in revenue service byMarch 1998 on three routes that travelthrough the downtown area for test andevaluation of the technology.

4.2.3 Hybrid Electric Developments

There are several programs underwayto develop a hybrid electric propulsionsystem for transit buses. One program thatwill have buses placed in revenue service inthe near future is the Orion VI Low-FloorHybrid-Electric bus. The New Jersey Transithas ordered four buses and they will bedelivered in the first quarter of 1998. TheNYCT has ten buses on order, and they arescheduled to be delivered in the secondquarter of 1998. The bus uses a LockheedMartin hybrid electric propulsion involving aDDC Series 30 engine, a 110kW generator,and AC traction motor, an advanced lead acidbattery pack, and an electric power controlsystem.

The Gillig Corporation is developinga hybrid electric propulsion system for their

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Table 4.5 Technical Characteristics of the ATTB

Source: References 34 and 35

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buses. The first propulsion system will betested in a Phantom 40-foot bus that will bedelivered to Golden Gate later this year. TheGillig hybrid-electric propulsion system issimilar in approach to the Lockheed Martinsystem, and includes an engine, generator,traction motor, battery pack, and powercontroller. Gillig plans to use the technologyin their low-floor bus, and be in productionin 3 to 5 years.

The FTA DUETS program involvesthe development of an advanced hybridelectric propulsion system for buses. TheNova Bus Corporation is the contractor forthe program. The test bed vehicle is an RTSbus that has two small rotary natural gasengines coupled to a generator. Power fromthe generator flows to the power control unitthen to two wheel hub motors. Thepropulsion system also includes a lead acidbattery storage system. A demonstrationtest of the system is scheduled to begin in1998.

4.2.4 Protected Position Design forWheelchair Accommodation

European research and standardsdevelopment efforts (References 12 and 31)have focused on an innovative approach toaccommodating passengers in wheelchairs onlow-floor buses, involving a "protectedposition" on the vehicle. This conceptinvolves two major elements: 1) a clearrectangular floor area of approximately 55 by28 inches, where a person in a wheelchaircan position themselves in a rear-facingposition, and 2) a load bearing back and headrest, which protects the passenger in case ofrapid deceleration. Flip-up seats are usuallyprovided to be used by other passengerswhen no passenger in a

wheelchair is present. In addition, a verticalaisle stanchion is typically provided toprevent the wheelchair sliding into the aisleduring bus turning movements.

Such an approach is reported toprovide: the same level of safety afforded toother seated bus passengers; moreindependence of the passenger in thewheelchair during boarding, riding, andalighting; and a safe wheelchair locationwithout the use of hooks or belts. Further, theapproach does not require the assistance ofthe operator. However, the wheelchairpassenger must face to the rear, which is notan issue in Europe, but is more of an issuefor North American buses. However,rearfacing seats are common in trains andsubways in North America.

This approach appears to offer manyadvantages and a high level of safety. It hasbecome the widely accepted standard inEurope, and the Canadian Urban TransitAssociation has been exploring itstransferability to Canadian transit systems(Reference 32). As a result, several Canadiantransit systems have adopted this approach.Examples of the "protected position" can beseen in Figures 2.5 and 4.2. The "protectedposition" does not meet the ADArequirement of a 20g deceleration, butstudies have shown that even extremebraking on buses rarely exceed 0.5g(References 31 and 33). A waiver would berequired to use the "protected position"approach in the United States.

4.2.5 Level Boarding Developments

According to a recent EuropeanCommunity (EC) report (Reference 15), theintroduction of low-floor buses should beseen as one step along the path to a more

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Figure 4.2 Hamilton Street RailwayLow-Floor Bus with Protected Position

Source: Canadian Urban TransitAssociation

passenger friendly transport system. The nextsteps that are being proposed are levelboarding, improvements in passengerinformation, and improvements in bus stopfacilities. Level access for all customers isregarded as one of the most importantfeatures of an attractive and modern meansof public transport.

In several cities in France andGermany, level board tests are underway.Level boarding is accomplished by raising

the level of the bus stop platform to the levelof the low-floor bus entrance. To minimizethe horizontal gap between the bus entranceand the bus stop platform, the bus must beconsistently brought close to the curb. It isdifficult for operators to consistently steerthe bus close to the curb without damagingthe tire or bus body. In several cities inGermany they are experimenting withspecial curb stones that are claimed to assistthe operators in steering the bus to the curbwithout damaging the tires. A photo of a"Bus Kap" in Aachen, Germany using thisapproach is shown in Figure 4.3. In thiscase, the bus stop was brought out to thetraffic lane, and the bus would stop in thetraffic lane. Since the honor fare collectionsystem enables all doors to be used to boardand alight, and there is no time lost by thebus trying to re-enter the traffic stream, thedwell time is quite short. Another approachused in Caen, France is shown in Figure 4.4.In this case, a steel tube imbedded in thecurb is used to protect the tire. In Grenoble,France, experiments are underway to useoptical guidance to steer the bus to the stop.In Essen, Germany, a guided bus route usesthe median of a four lane highway to Kray.There are three stations located along theroute. The route has only low-floor busesoperating on the route. The guided bussystem operates in this case like a rubbertired rail system. The station platforms areat the same level as the floor level of theguided bus. The interface between vehicleand station platform is as good as any highplatform rail system. A photo of a low-floorguided bus stopped at a station is shown inFigure 4.5.

In August 1997, a successfuldemonstration of full automatic control oftwo MTA low-floor buses wasaccomplished. The buses were equipped

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with both vision and radar sensors to controlthe bus in both lateral and longitudinaldirections. Such technology could also beused to steer a bus close to a bus stopplatform.

Figure 4.3 Raised Bus Stop in Aachen, Germany

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Figure 4.4 Raised Bus Stop in Caen, France

Figure 4.5 Low-Floor Guided Bus at a Station in Essen

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5.0 CONCLUSIONS AND RECOMMENDATIONS

Since their first deployment in 1991,low-floor buses have increasingly becomethe choice of transit agencies in both theUnited States and Canada. By December1997, there were over 2,800 low-floor busesin operation and over 2,600 on order in NorthAmerica. There are six manufacturers thatare offering heavy-duty, standard-size, low-floor buses to the transit market.

5.1 Conclusions

The significant findings frominterviews with transit agencies operatinglow-floor buses and discussions with busmanufacturers are provided below:

5.1.1 Customer Satisfaction andAcceptance

• Customers liked the ease ofboarding and alighting of the low-floor buses. Seniors and peoplewith disabilities expressed even astronger preference for low-floorbuses. Most wheel-chairpassengers preferred a ramp over alift.

• Other features that customers likedwere the ability to see out of thelarger windows, the feeling of aspacious environment with thehigher ceilings, and places to putpackages.

• Customers also had complaintsconcerning issues such as: lack ofseats, crowding, noise andvibration, windows fogged

("can't see out"), concerns aboutthe safety of the steps in the aisle,and a "jerky" ride. Only onetransit agency had received manyvocal customer complaints abouttheir low-floor buses. The mainfocus of their complaints wascrowding and inability to movefreely through the bus, althoughit should be noted that theaverage loads of the buses weremuch higher at this transitagency.

• Six transit agencies hadconducted customer surveys. Alarge majority of customers gavea positive rating of the low-floorbus, and only four to nine percentgave a negative rating for theirlow-floor bus. One survey foundthat peak period riders preferredthe conventional high-floor busbecause the low-floor buses hadless seats and lack of room forstandees, while the non-peakriders preferred the low-floorbus.

5.1.2 Customer Comfort andEnvironment

• Overall, the customers weresatisfied with the comfort andenvironment of the low-floorbuses.

• Some complaints had also beenreceived:

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- During rainy or snowy days,the windows can becomeobscured with road grime andspray, making it difficult to seeout.

- On very cold days,passengers' feet got cold, andsome customers werebothered by the noise and/orvibration of the low-floorbus.

- Sudden and unexpected changesin acceleration and decelerationarising from harsh braking orlack of smooth transition inpower gave a jerky ride.

The initial low-floor buses hadinadequate heating systems. Improvementsmade in the heating systems are improvingthe situation, except perhaps for very coldclimates. The vibration complaints wereusually received with buses powered by fourcylinder engines. The noise complaintsusually came from passengers seated in therear of the bus next to the enginecompartment.

• Tests conducted by CUTA foundthat only one of the low-floorbuses tested met an ASHRAEStandard for fresh air in thepassenger compartment. The testalso indicated problems withuneven heat distribution in thepassenger compartment.

• Several of the transit agenciesreported having dusty buses. Thereasons for the higher level ofdust intrusion are not fullyunderstood.

5.1.3 Capacity and Ridership

• For the currently available low-floor, 40-foot buses, the maximumnumber of seats (using only frontand aisle-facing) range from 35 to40, compared with a range of 43 to45 for high-floor models. If atransit agency's loading standard isto provide a seat for all expectedcustomers, then the loss incapacity on a route would beproportional to the reduction in thenumber of seats, assuming nochanges in schedule speed andheadway.

• Most agencies interviewedreported that they had made nochanges in their schedules oradded buses with the introductionof low-floor buses in their system.Two agencies reported that thelower capacity of their low-floorbuses would probably requireadding more buses on routes tomaintain their service standards.They were experiencing rapidgrowth in ridership, and buses hadbeen added to routes. They couldnot say what portion of the needfor more buses was due to increasein riders or what portion wascaused by the lower capacity oftheir low-floor buses.

• None of the agencies operatedroutes with all low-floor busesduring the peak periods.

• The CTA reported no changeswere required when theyintroduced the low-floor buses intheir system. The CTA uses thesame maximum capacity (70) for

58

their low-floor buses as is used fortheir high-floor buses whenassigning buses to routes.

• The STCUM said that forscheduling purposes their low-floor bus with 39 seats had a"natural" capacity of 65passengers, compared to a"natural" capacity of 80 for theirhigh-floor buses. However, theSTCUM is evaluating a newinterior design for their low-floorbuses which they feel has a"natural" capacity of 80, which isthe same as their high-floor buses.While the new interior designprovides an equivalent vehiclecapacity, there are 24 percentfewer seats (31 versus 41), and theservice quality (measured by thenumber of seats provided) wouldbe lower.

• Boarding times for an ambulatorypassenger on a low-floor bus werereported to be from 0.2 to 0.7 of asecond faster. Alighting times foran ambulatory passenger werereported to be from 0.3 to 2.7seconds faster, and, in one case,0.3 second slower. The case of theslower alighting time wasattributed to a change in how theexit door was activated.

• None of the agencies reportedany increases in schedule speedwith the introduction of low-floorbuses to their fleet though littleformal evaluation had beenconducted.

• During the Paralympics, theboarding times for athletes inwheelchairs for both low-floor

and high-floor buses weremeasured. The mean boardingtimes (not including maneuveringinside the bus or securement) for alow-floor bus was about 27.4seconds, while the mean boardingtime for a high-floor bus was about46.4 seconds. The report alsonoted that only one deployment ofa ramp is required, irrespective ofthe number of boarding oralighting persons with mobilityaids.

5.1.4 Vehicle Operating Experiences

• All agencies were generallysatisfied with the road clearancecapabilities of the low-floorbuses. Some reported that theprotective skid for the ramp cammechanism would occasionallyground on steep ramps, and somereported grounding on some highrailroad crossings and largespeed bumps.

• The low-floor buses tended to bequicker and had good handlingcharacteristics.

• The CDTA reported somesteering problems during aheavy, wet snow storm with theirlow-floor buses. Slush and icebecame packed around thesteering linkages, and restrictedthe operator's ability to steer thebus. The manufacturer hasprovided a fix that seems to beworking.

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5.1.5 Impacts on Maintenance

• Transit agencies were generallysatisfied with their maintenanceexperiences. Many of the earlyproblems experienced by thetransit agencies appear to be"new bus model" problems,rather than problems intrinsicallyrelated to a low-floor bus design.All agencies had a "punch list" ofproblems that needed to beresolved.

• Three maintenance items thatwere consistently reported by thetransit agencies as beingsignificantly different incomparison with their high-floorbuses were:

- The operating experienceswith the ramp have beenuniversally positive. TheU.S. transit agencies reportedthat service interruptionsbecause of ramp failureseither did not occur or wererare. Lift failure is a majorcause of road calls for manyU.S. transit agencies. Inaddition, the cost ofmaintaining lifts has beenreported to be significantlyhigher than the cost ofmaintaining ramps. Thecosts per bus per year rangedfrom $50 to $300 for rampsand from $1,500 to $2,400 forlifts.

- All of the low-floor buses at thetransit agencies used a low-profile radial tire, either a275/70R22.5 or a

305/70R22.5. All indicatedthat they were getting from20 to 30 percent less mileswith their low profile tires.Also, several agenciesreported more wheel damagefrom hitting curbs with theirlow-floor buses. TheSTCUM has noted a higherwear rate on their curb side,dual tires compared with thestreet side, dual tires. Thewear rate difference wasthought to have been caused bythe right side, dual tiresslipping.

- Problems reported with thebrakes were: brake effortbalance between front and rearbrakes, timing of brakeapplication, and the short life ofbrake linings. The busmanufacturer conducted aretrofit program and correctedthe imbalance and timingproblems. The life of brakelinings is improving, but formany properties, it is stillshorter than desired. Theproblems with the brakesappear to have resulted becausethe bus was a new bus designrather than a low-floor design.

5.1.6 Maintenance Facilities Impacts

• The changes needed in themaintenance facilities with theaddition of low-floor buses to afleet have been minimal. Nochanges had been made to the

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maintenance pits. Some havefabricated fixtures to adapt theirexisting hoists to theundercarriage of their low-floorbuses.

• To work on roof mountedcomponents, some used stepladders; others used movable workplatforms.

• All agencies have purchased somespecial tooling and adapterslargely because it was a new bus intheir fleet.

• Several agencies had madeadjustments to the height of thebrushes on their bus washer. TheCTA had fabricated a shim for thetire guide of their bus washer sothat the low-floor bus wheel wouldnot contact the curb as it travelsthrough the washer.

5.1.7 Safety Experiences

• All transit agencies were satisfiedwith their safety experiences withtheir low-floor buses. However,few had data to support theirperceptions.

• Some transit agencies reported thatthe number of passenger accidentsper low-floor bus was higher thanthe passenger accidents per bus fortheir high-floor fleet. All of theagencies cautioned against makinga simple comparison of the databecause of the small amount ofdata, and the exposure of the low-floor buses (more passengers andmore miles per bus) tended

to be higher than for their high-floor buses.

• Some agencies felt that the higherfrequency of slips and falls ofpassengers occurring in the frontof the low-floor buses could berelated to the lack of an adequatenumber of handholds from thefarebox to the first row of seats.

• The steps in the aisle have beenperceived as a safety hazard byboth transit customers and transitstaff, and concerns about thesteps were reported in several ofthe customer surveys. Theoperating experiences to date donot indicate that the stepsrepresent a safety hazard. Alltransit agencies that wereoperating low-floor buses withsteps in the aisle reported thatthey have not had any safetyincidents caused by the steps.

5.1.8 Operator and Mechanic Acceptanceand Satisfaction

• Overall, operators were satisfiedwith their low-floor buses.Operators liked the ease ofcustomer boarding, the ease ofusing the ramp (and the ease ofmanual operation of the ramp), thequickness and handling of the bus,the improved visibility, and theeye level contact they have withcustomers. When asked aboutconcerns, a senior operator at CTlisted the following: congestion inthe front of the bus, the flow ofpassengers to the rear

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of the bus, insufficient heat duringextremely cold weather, the jerkyride quality, and a blind spotcreated by the frame of the frontdoor panels.

• Surveys conducted at MARTA andNYCT found that their operatorsliked the improved visibility,handling, and noise level, butexpressed concerns about steps inthe aisle and the right side mirrorbeing too low (hazard topassengers).

• The majority of mechanics weresatisfied with their low-floorbuses. Some mechanics preferredto work on the low-floor busessince everything was cleaner andaccessible (many componentsmoved from under the bus to theroof area), while others expressedsome concerns about workingfrom ladders and elevatedplatforms.

• One service person pointed outthat the higher ceilings were a littlemore difficult to clean. However,most agencies felt that there wereno significant differences in thecleaning and servicing of the low-floor buses.

5.1.9 Market Status and Trends

• Only Neoplan USA and New FlyerIndustries were delivering heavy-duty, low-floor buses from 1991through 1995. Nova Bus and OrionBus Industries began deliveringlow-floor models in 1996 and1997. Gillig and North AmericanBus Industries will

begin delivery of heavy-duty, low-floor buses in the first quarter of1998.

• At the end of 1997, busmanufacturers reported that 2,812low-floor buses had beendelivered, and that they had ordersfor another 2,660.

• With the entry of moremanufacturers to the low-floormarket, the number of deliverieshas grown rapidly. There were1,185 low-floor buses (35, 40, and60-foot) delivered in 1997.

• It is estimated that low-floormodels were 30 to 40 percent ofthe 1997 heavy-duty bus marketin North America. Three of themanufacturers estimated thattheir sales of buses in 2000would be 50 to 90 percent lowfloormodels.

5.1.10 Technology Status andDevelopments

• All six of the manufacturers offera 40-foot bus to the transitmarket, and four offer 35-footmodels. Only one manufactureroffers 30, 35, 40, and 60-footmodels.

• All have low-floor modelspowered by diesel engines. Fouroffer the option of compressednatural gas (CNG), and two haveoptions for liquefied natural gas(LNG).

• There are several R&D programsunderway that could lead tosignificant advances in

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technologies used in low-floorbuses.- The ATTB is a major FTA

program to develop alightweight, low emission, lowoperating cost, low-floor busfor the next century. Sixprototypes have beenfabricated. Testing isunderway at the Altoona BusTesting Center with one ofthe buses. Three of theprototypes will bedemonstrated at various transitagencies during 1998.

- Ballard Power Systems hasinstalled their fuel cell enginein seven New Flyer Industrieslow-floor buses. Three buseswere delivered to both theCTA and the BC Transit-Vancouver for test andevaluation in revenue service.

- The FTA Fuel Cell Transit BusProgram is a cooperativeprogram with the DOE todesign a 40-foot bus poweredby a fuel cell system. Aprototype fuel cell systeminstalled in a Nova Bus RTSwill be delivered fordemonstration and testing in thesummer of 1998.

- A low-floor, hybrid-electricbus is under development byOrion Bus Industries andLockheed Martin. The initialproduction models will bedelivered to the New JerseyTransit (four buses) and theNew York City Transit (tenbuses) in the first half of1998. These buses will be

placed in revenue service fortest and evaluation.

- The Gillig Corporation isdeveloping a hybrid-electricpropulsion system for theirbuses. The first delivery willbe in a Phantom to bedelivered to Golden Gate inthe spring of 1998. Alow-floor bus using thispropulsion system isexpected to be in production in3 to 5 years.

- Most European and a numberof Canadian transit systemsare adopting the rear-facing"protected position" design toaccommodate passengers inwheelchairs. This approachuses a backrest to protect thepassenger duringdeceleration. It is extremelyattractive because it involves nostraps or mechanical devices,no operator involvement, andenhanced passengerindependence.

- Several cities in Europe aredemonstrating variousapproaches to level boardingwith low-floor buses. Toachieve an acceptablehorizontal gap between thebus entrance and the stationplatform, some method ofaiding the operator orautomatically steering the busclose to the curb is required.Mechanical, optical, andelectronic guidanceapproaches are underevaluation.

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5.2 Recommendations

Based upon the insights gained duringthe course of this study, the followingresearch topics are recommended forconsideration:

• Reduction in Dwell Times. Low-floor buses enable the fasterboarding and alighting ofpassengers. For ambulatorypassengers, the average reportedtime savings was about 0.5seconds per passenger, and forpassengers with disabilities theaverage reported time savings wasapproximately 19 seconds.However, to take advantage ofthese quicker boarding andalighting times, a faster farecollection process is needed. Forexample, a "proof of payment"system or "smart card" systemwhere bus passengers can use alldoors would significantly shortendwell times. Facilitating a fast andsafe reentry of the bus into thetraffic stream would aid inreducing dwell times. Buses in theprovince of Quebec, and morerecently in the State ofWashington, are given the right-of-way when they emerge from a busstop to reenter the traffic stream.Bringing the bus stop adjacent tothe traffic lane so that the bus stopsin the traffic lane is anotherapproach that has beenimplemented by some transitagencies.

• Development of LevelBoarding System. Low-floorbuses hold the potential to offer

level boarding to bus customerscomparable to those that exist forhigh platform rail systems.Various schemes are being testedin Europe to assist the operator tosteer close to the curb of a raisedbus stop platform. Automaticguidance approaches are alsounder development andevaluation. Mechanical guidancehas been in use in Germany forover 15 years. Optical andelectronic methods are also underdevelopment and evaluation.The development of a levelboarding system for buses wouldbenefit all customers and wouldaid in reducing dwell times, thushaving beneficial effects ontraffic flow and environmentalpollution.

• Improved PassengerHandholds in the Front of theBus. A high percentage ofpassenger slips and falls haveoccurred in the area between thefarebox and the first row of seats.When the wheelchair positionsare located in the front of the bus,there are distances of six to eightfeet where vertical stanchions arenot available for passengers tograsp as they move to the rear ofthe bus. The horizontal grab baris too high for some passengersto reach. The straps used bysome agencies have helped, butare not a complete solution. Thestraps do not provide a firm handhold for the elderly, and somepassengers cannot raise theirarms to reach the strap.Improvements in passenger

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handholds would reduce thepassenger slips and falls while onthe bus. This might, forexample, build on the prototypeefforts carried out at CalgaryTransit.

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(30) Summary of Canadian Transit Statistics, 1996 Data, Canadian Urban TransitAssociation.

(31) Rutenberg, U., "Urban Transit Bus Accessibility Concerns," Canadian Urban TransitAssociation, TCRP Report 10 (August 1995).

(32) Rutenberg, U., "Advanced Concepts to Accommodate Mobility Aids on CanadianLow-Floor Buses," Canadian Urban Transit Association, TCRP Report 15,(Forthcoming).

(33) Tests to Determine Regular Service and Emergency Acceleration Forces, Performed byGOTransit, (May 1993).

(34) Technical Developments and Configuration Decisions, Northrop Grumman, Bi-Monthly Report, (March/April, 1995).

(35) Advanced Technology Transit Bus, FY94 Technology Validation Final Report,Volume II Technical Report Updates, Northrop Grumman, (March 1995).

68

ACRONYMS AND ABBREVIATIONS

Bus Manufacturers

Gillig Corporation GILFlxible Corporation FLXMotor Coach Industries International MCINeoplan USA Corporation NEONew Flyer Industries Limited NFILNorth American Bus Industries NABINova Bus Corporation NOVOrion Bus Industries OBITransportation Manufacturing Corporation TMC

Transit Agencies

Ann Arbor Transportation Authority AATABC Transit - Victoria Regional Transit System VRTSCalgary Transit CTCapital District Transportation Authority CDTAChampaign-Urbana Mass Transit District MTDChicago Transit Authority CTAMetropolitan Atlanta Rapid Transit Authority MARTAMetropolitan Transit Authority of Harris County MTAMTA New York City Transit NYCTMilwaukee County Transit System MCTSPhoenix Transit System PTSSociété Transport de la Communauté Urbaine de Montréal STCUMSociété de Transport de la Rive-Sud de Montréal STRSM

Government Agencies

Federal Transit Administration FTATransportation Research Board TRBVolpe National Transportation Systems Center VNTSC

Organizations

American Public Transit Association APTACanadian Urban Transit Association CUTA

APPENDIX A

TECHNICAL DESCRIPTIONOF LOW-FLOOR FLEETS

A-1

TECHNICAL DESCRIPTION OF LOW-FLOOR FLEETS

A more complete description of the low-floor bus fleets that were included in the study isgiven in Table A-1.

Table A-1. Information on Low-Floor Fleets

(a) STCUM has a test seating arrangement with less seats to facilitate passenger flow.(b) STRSM replaced two forward facing seats behind the driver with an aisle facing seat.

APPENDIX B

DISCUSSIONS OF FACTORSIMPACTING CAPACITY

B-1

DISCUSSIONS OF FACTORS IMPACTING CAPACITY

The theoretical maximum number of passengers that can be carried on a line is a functionof the capacity of the buses operating on the line and the average headway between buses on theline. The formula used to calculate the capacity of a line is: C = B × 60/H.

Where: C = capacity of the line, usually expressed as passengers per hour perdirection (ppdph),

B = the capacity of the bus, expressed as the maximum number ofpassengers the bus can carry, and

H = the average operational headway of buses operating on the line,expressed in minutes.

The number of buses required for a line is a function of the length of the line, the averageheadway between buses, the average operating speed for the line, and the duration of layovers atthe ends of the line. The number of buses required for a line can be estimated by the followingformula: TNB = (60 × LL / S + 2 × LT) / H.

Where: TNB = the total number of buses,LL = the length of the line in miles,S = the average speed along the line, in miles per hour,LT = the layover time, in minutes, andH = The average operating headway, in minutes.

The average speed, S, along a line is a function of the number of stops along the line, theaverage dwell time per stop, and the average time that is required to move from stop to stop. Lineattributes such as whether or not it is an exclusive bus lane and does a bus have priority atintersections affect the average speed. The average dwell time is a function of the averageboarding and alighting times for passengers, method of fare collection (can more than one doorbe used for boarding), and the average time required to re-enter the traffic stream if the bus isoperating in a mixed traffic lane. The following formula (Reference B-1) can be used toapproximate the average speed of a bus along a line:

Where: S = average bus speed,T = average dwell time at stops,D = average distance between stopsC = average cruising speed in lane (e.g., 50 kph),a = average rate of acceleration of bus (e.g., 5 kph/sec.), andd = average rate of deceleration of bus (e.g., 6 kph/sec.).

B-2

The average speeds of the transit agencies interviewed ranged from 25 to 16 kph (15.5 to9.9 mph). The minimum headway was reported to be two minutes.

(B-1) Quinby, H.D., "Mass Transportation Characteristics," in Transportation and TrafficEngineering Handbook, Institute of Transportation Engineers, Prentice Hall, New Jersey(1976).

APPENDIX C

INTERVIEW GUIDE AND SURVEY FORM

C-1

INTERVIEW GUIDE AND SURVEY FORM

The interview guide that was used for the site visits to the transit agencies and the surveyform that was given to all six of the heavy-duty bus manufacturers that are offering low-floorbuses to agencies are provided in the following pages.

C-2

INTERVIEW GUIDE for TCRP PROJECT ON"NEW DESIGNS AND OPERATING EXPERIENCES WITH LOW-FLOOR BUSES

PURPOSE: TO GATHER AND SYNTHESIZE INFORMATION AVAILABLE AS TO THEOPERATING EXPERIENCES OF TRANSIT AGENCIES THAT CURRENTLYOPERATE LOW-FLOOR BUSES, INCLUDING USER SATISFACTION ANDACCEPTANCE, SAFETY, NOTABLE FEATURES AND CONCERNS, ANDIMPACTS ON RIDERSHIP, MAINTENANCE, AND OPERATIONS.

AGENCY NAME DATE

CONTACT TEL

TITLE FAX

ADDRESS (STREET)

(CITY) (STATE) (ZIP)

FLEET INFORMATION

• TOTAL FLEET SIZE: PEAK: AM PM BASE:

• LOW-FLOOR FLEET

• REASONS FOR PURCHASING LOW-FLOOR BUSES:

• PLANNED FLEET IN 5 YEARS: % LOW-FLOOR

• CAN YOU PROVIDE A COPY OF THE SEATING ARRANGEMENT?

C-3

CUSTOMER SATISFACTION/ACCEPTANCE

• DO YOU HAVE ANY SURVEYS/REPORTS ON CUSTOMER SATISFACTIONAND ACCEPTANCE OF LOW-FLOOR BUSES? IF YES, CAN COPIES BEPROVIDED?

DID THESE STUDIES INCLUDE BOTH AMBULATORY, DISABLED, ANDSENIOR PASSENGERS, AND DID THE ANALYSIS EXAMINE THERESPONSES FROM EACH GROUP SEPARATELY?

DO YOU HAVE OTHER SOURCES OF INFORMATION ON CUSTOMERSATISFACTION OR ACCEPTANCE OF LOW-FLOOR BUSES, SUCH AS:PASSENGER COMPLAINT DATA OR OPERATOR REPORTS?

TYPES OF CUSTOMER SATISFACTION/ACCEPTANCE INFORMATIONSOUGHT INCLUDED:

- BOARDING/ALIGHTING -- EASE, ENTRANCE/EXIT HEIGHTS, RAMPS

- PASSENGER COMFORT -- HEATING/VENTILATION, A/C, NOISE,VIBRATION

- PASSENGER VIEW -- HEIGHT, WINDOWS FOGGING UP, ROAD SPRAY

- SEATING -- LACK, ARRANGEMENT, PERCEPTION OF INTERIOR SPACE

- HAND HOLDS/PASSENGER ASSISTS -- LOCATION AND ADEQUACY

- SAFETY & SECURITY -- INCLUDING PERCEPTIONS

- FLOOR -- BI LEVEL (INTERIOR STEPS), SLOPES (OVER AXLE)

- EXIT DOOR BEHIND REAR AXLE

- LOCATION OF RAMP -- FRONT DOOR VERSUS REAR DOOR

- OTHER

• HAVE THE LOW-FLOOR BUSES ATTRACTED DIFFERENT CUSTOMERS (e.g.MORE OLDER AND LESS MOBILE PEOPLE)?

C-4

OPERATIONAL EXPERIENCES

• WHAT HAVE BEEN YOUR EXPERIENCES WITH OPERATING YOUR LOW-FLOOR BUSES? TYPES OF INFORMATION DESIRED INCLUDE THEFOLLOWING:

- IMPACTS ON RIDERSHIP

- CAPACITY ISSUES WITH FEWER SEATS (WAS ADDITIONAL SERVICEADDED TO COMPENSATE)?

- DWELL TIME AND SCHEDULE IMPACTS

- BOARDING/ALIGHTING TIMES - - AMBULATORY, SENIORS, DISABLED

- MOBILITY DEVICE LOCATION

- FARE COLLECTION ERGONOMICS

- EXIT DOOR BEHIND REAR AXLE

- RIDE QUALITY

- FLOW OF PASSENGERS (ESPECIALLY BETWEEN FRONT WHEELHOUSINGS)

- UNCONVENTIONAL SEATING (e.g. REARWARD FACING, SEATS ONPEDESTALS)

- OTHER

DO YOU HAVE AVAILABLE REPORTS/DATA ON ANY OF THE ABOVE TOPICS? CANYOU PROVIDE COPIES?

C-5

OPERATIONAL EXPERIENCES (continued)

• HAVE YOU HAD ANY PROBLEMS WITH ANY OF THE FOLLOWING?

- ROAD CLEARANCES OF THE BUS (damage due to lack of clearances)

- DRIVING/HANDLING (road conditions: dry, snow, ice, wet)

- DRIVING IN HIGH WATER

- WATER OR DUST INTRUSION INSIDE THE BUS

- WINTER OPERATIONS (e.g. windows fogging up, passenger comfort)

- DRAINAGE OR BUILD UP OF SNOW OR ICE IN DOOR AREAS

- PASSENGER VISIBILITY (road spray on windows)

- OPERATOR VISIBILITY (e.g. road spray on windows/mirrors, glare)

- NOISE (interior and/or exterior) OR VIBRATION

- RAMP BOARDING FROM STREET LEVEL (i.e. no curb)

- RAMP OPERATIONS, FRONT/REAR

- KNEELING

- OPERATING RANGE

- BRAKING

- TRACTION

- OPERATION OF ROOF HATCHES (e.g. too high to open/close)

- EMERGENCY EXIST

ARE REPORTS OR DATA AVAILABLE ON ANY OF THE ABOVE TOPICS?

C-6

MAINTENANCE EXPERIENCES

WHAT HAS BEEN YOUR EXPERIENCES WITH THE MAINTENANCE OF THE LOW-FLOOR BUSES? CAN YOU PROVIDE INFORMATION ON ANY OF THE FOLLOWING(including comparison with high-floor bus maintenance experience)?

- MAINTENANCE COSTS

- ROADCALLS (i.e. frequency)

- SERVICING THE LOW-FLOOR BUSES ON THE STREET (i.e. special tools)

- RAMP MAINTENANCE (including comparison with lift maintenance)

- TIRE WEAR OR EXCESSIVE DAMAGE

- SPECIAL TOOLS AND EQUIPMENT

- FACILITIES MODIFICATIONS (i.e. changes to hoists or pits)

- ACCESSIBILITY (i.e. systems and equipment mounted in roof area)

- INDEPENDENT FRONT SUSPENSION OR FRONT AXLES

- BRAKE WEAR

- FLOOR CLEANING

SAFETY EXPERIENCES

WHAT HAS BEEN YOUR EXPERIENCES WITH RESPECT TO SAFETY WITH YOURLOW-FLOOR BUSES? CAN YOU PROVIDE INFORMATION ON ANY OF THEFOLLOWING?

- SLIPS AND FALLS WHILE BOARDING AND ALIGHTING

- SLIPS AND FALLS ON-BOARD

- INTERIOR STEP INCIDENTS

- RAMP INCIDENTS

- DOOR AND DOOR AREA INCIDENTS

- OTHER

C-7

OPERATOR SATISFACTION/ACCEPTANCE EXPERIENCES

WHAT HAS BEEN THE ACCEPTANCE OF YOUR LOW-FLOOR BUSES BY YOUROPERATORS? HAVE YOU CONDUCTED ANY SURVEYS OF YOUR DRIVERS WITHRESPECT TO THE LOW-FLOOR BUSES?

DO YOU HAVE INFORMATION ON OPERATOR ACCEPTANCE OF ANY OF THEFOLLOWING?

- DRIVEABILITY AND HANDLING

- OPERATOR PLATFORM HEIGHT

- OPERATOR COMFORT - HEATING AND VENTILATION AND A/C

- ADEQUACY OF DEFROSTER SYSTEM

- VISION -- MIRRORS, GLARE, BLIND SPOTS

- SEPARATION OF PASSENGER AREA FROM OPERATOR'S COMPARTMENT

- FARE BOX ACCESSIBILITY

- PASSENGER FLOW

OTHER COMMENTS

C-8

BUS MANUFACTURERS' SURVEYFOR TCRP PROJECT ON

NEW DESIGNS AND OPERATING EXPERIENCES WITH LOW-FLOOR BUSES

PURPOSE: TO GATHER INFORMATION ON HEAVY-DUTY, LOW-FLOOR BUSTECHNOLOGY AND THE MARKET STATUS OF LOW-FLOOR BUSESAVAILABLE TO TRANSIT SYSTEMS IN THE U.S. AND CANADA.

NAME DATE

CONTACT TEL

TITLE FAX

ADDRESS (STREET)

(CITY) (STATE) (ZIP)

STATUS OF LOW-FLOOR TECHNOLOGY

1) WHICH MODELS OF HEAVY-DUTY, LOW-FLOOR BUSES DO YOU OFFEROR PLAN TO OFFER TO THE TRANSIT MARKET? (PLEASE CHECK ALLTHAT APPLY)

40-FOOT [ ] 35-FOOT [ ] 30-FOOT [ ] ARTICS (55/60') [ ]

2) AT WHAT STAGES OF DEVELOPMENT ARE YOUR LOW-FLOOR BUSMODELS? (PLEASE CHECK THE STAGE OF DEVELOPMENT FOR EACHMODEL)

C-9

STATUS OF LOW-FLOOR TECHNOLOGY (continued)

3) WHICH TYPES OF PROPULSION SYSTEMS ARE AVAILABLE (OR AREPLANNED TO BE AVAILABLE) FOR YOUR LOW-FLOOR BUSES? (PLEASECHECK ALL THAT APPLY)

(a) Diesel engine with an electric traction motor.(b) Other than diesel engine with an electric traction motor.(c) Diesel engine with wheel hub motors.(d) Other than diesel engine with wheel hub motors.

4) PLEASE PROVIDE INFORMATION ON THE TECHNICAL SPECIFICATIONSAND OPTIONS OF YOUR LOW-FLOOR BUSES ON THE FORMS PROVIDED,PAGES 4 AND 5, OR PROVIDE BROCHURES WITH THE INFORMATION.

5) PLEASE PROVIDE A DRAWING(s) OF YOUR MAXIMUM SEATINGARRANGEMENT.

6) PLEASE PROVIDE INFORMATION ON THE TYPE OF ELECTRICAL SYSTEMMULTIPLEX THAT IS USED.

C-10

MARKETING STATUS OF LOW-FLOOR BUSES

1) PLEASE PROVIDE THE NUMBER OF HEAVY-DUTY, LOW-FLOOR BUSES(12 YEAR) DELIVERED BY MODEL AND BY YEAR IN THE FOLLOWINGTABLE.

2) PLEASE PROVIDE THE NUMBER OF HEAVY-DUTY, LOW-FLOOR BUSESYOU HAVE ON ORDER BY MODEL.

3) WHAT PERCENTAGE OF YOUR TOTAL BUS SALES IN 1996 WAS FORLOW-FLOOR BUS MODELS? WHAT PERCENTAGE DO YOUANTICIPATE IT WILL BE IN 2000?

4) IS THERE A COST DIFFERENTIAL FOR LOW-FLOOR BUSES OVERCOMPARABLE HIGH-FLOOR MODELS? YES [ ] NO [ ]

IF YES, WHAT IS THE TYPICAL DIFFERENTIAL?

C-11

TECHNICAL SPECIFICATIONS OF LOW-FLOOR BUSES

(a) Maximum number of seats with two wheelchair positions (no wheelchair riders on board)using a hip to knee room of approximately 26.5 inches.

(b) Use 1.5 square feet of free floor space per standee.

C-12

OPTIONS OFFERED ON LOW-FLOOR BUSES(PLEASE ADD OTHER OPTIONS OFFERED)

APPENDIX D

LISTING OF PARTICIPANTS

D-1

LISTING OF PARTICIPANTS

The following transit agencies and bus manufacturers participated in this study.

Transit Agencies

Ann Arbor Transportation AuthorityBC Transit - Victoria Regional Transit SystemCalgary TransitChampaign-Urbana Mass Transit DistrictCapital District Transportation AuthorityChicago Transit AuthorityMetropolitan Atlanta Rapid Transit AuthorityMetropolitan Transit Authority of Harris CountyMilwaukee County Transit SystemPhoenix Transit SystemSault Ste. Marie TransitSociété de Transport de la Communauté Urbaine de MontréalSociété de Transport de la Rive-Sud de Montréal

Bus Manufacturers

Gillig CorporationNeoplan USA CorporationNew Flyer Industries LimitedNorth American Bus IndustriesNova Bus CorporationOrion Bus Industries

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