APPENDIX B 

 Travel Time 



The time in travel was considered to be entirely associated with 

 mileage. However, travel time includes the running time over the road 

 plus allowance for driver comfort and food stops, and some breakdown 

 time. In a study made at the New Hampshire Agricultural Experiment 

 Station the relation between trip mileage and truck operating time was 

 established. ^ That study reported only net running time, so it had to be 

 adjusted to account for other time. This was done with data collected 

 about egg hauling trucks. The basic shape of the relationship used in the 

 Rogers and Woodworth study was retained because it "exhibits the log- 

 ical behavior of increasing average miles per hour with greater route 

 length." 2 



The function relating time to distance is : 



1. For trips up to 60 miles in length 



T = 2.865 + 2.6818D — 0.0102D2 



2. For trips exceeding 60 miles in length 

 T = 50 + 1.299D 



Tmiere : 



T = time in minutes 

 D = road miles 



The time used in truck and automobile travel was determined from 

 this relationship. This assumes that the trucks, and the automobiles 

 hauling the crew, travel at the same rate of speed under similar con- 

 ditions. 



A truck trip to collect poultry involves a round trip to the impound 

 point in the supply band involved. The mileage the truck covers to get 

 to that point is developed according to the procedures outlined in Ap- 

 pendix A. This one-way trip in miles was converted into time using one 

 or the other of the functions above, and then doubled to obtain round- 

 trip time. 



The determinations of the size of the supply area, the radius of the 

 supply area, the radial distance to the impovmd point, and the relation- 

 ship between radial distance to the impound point and the hours of truck 

 travel for a round-trip are illustrated for Supply Band IV at the 5.000 

 pound per year density level: 



Firm C 



Annual volume 24.9 million pounds 



Size of supply area: 



24.9 million pounds . _„„ ., 



zr^—-r^ :. — = 4,980 square miles 



5,000 pounds ^ 



Radius of Firm C supply area 39.81 miles 



1 G. B. Rogers and H. C. Woodworth, Distributing and Handling Grain Feeds in 

 Neiv Hampshire, 2. Problems in Retail Distribution, University of New Hampshire, 

 Agricultural Experiment Station Bulletin, No. 427, 1956, pp. 36-37. The authors state: 

 ". . . it covers only truck travel and no other time factors." 



2 Ibid. 



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