Transcription of HANDBOOK FOR THE ACCIDENT RECONSTRUCTIONIST
1 ! -~ . ~1 -------~--. I' HANDBOOK FOR THE ACCIDENT RECONSTRUCTIONIST M. J. LOFGREN INSTITUTE OF POLICE traffic MANAGEMENT UNIVERSITY OF NORTH FLORIDA ., c . ---~ -~--~~.. ------~-------"------~---. ~_. If you have issues viewing or accessing this file contact us at ~. ----" ------~~----------_____ t_ ---. Department of Justice National Institute oi Justice This document has been reproduced exactly as received from the person or organization originating it. Points of view or opinions stated in this document are those of the authors and do not necessarily represent the official position or pOlicies of the National Institute of Justice.
2 Permission to reproduce this copyrighted material in mi-crofiche only has been oranted h, . - -_ :c. F':r f\J\ . __ _ U V)\V, -of NOF;rH-E \ Dc= the National Criminal Justice Reference Service (NCJRS). Further reproduction outside of the NCJRS system requires permis-sion of the copyright owner. ~". t~ ~ .. o -----~~~-----~------ABOlIT THE AlITHOR Myron J. Lofgren was born November 1,:)" 1931. A native of Mirmesota, he served 21 years in the Minnesota State Patrol. In 1974, he h'as named Minnesota Trooper of the Year ,UlL! in 1979, National Police Officer of the Year. No,," in private practice, ~h'.
3 Lofgren i:-; a consul tant to \'ariOlLs law enforcement agen-cies in sCYcral states as h'cll as to insur-ance comp,mies Lllld to law filllL'i that require ACCIDENT reconstruct ion for lL"e in ch'i 1 li tigLl t ion. ~1r. Lofgrcn also teaches ~m ACCIDENT l'l'con-structioll courSL' offL'n:d se"veral times each YL'ar by the InstitutL, of Police TI'arGc ~1,Ulagelllellt at the Uni wI'si ty of :\ort11 Flor-Myron J. Lofgren ida in Jacksonv ill e. Ill' [ol1J:er]y taught \,:L)Llrses in acnJL'llt imcst igation for Nort11\"estc111 Uni \'crs i ty traffic Institute in Evunston, Illinois. He has conducted seminars in ACCIDENT im'cst igation ,UlU reconstruction for police officers from all over the l tli tl.
4 'U States ,UlU froT:1 other cOlUltries lUId for the Minllesota Supreml' L:oun, thc :\J]1crican Bar :\..ssociation, otner bouies of juuges ,md attor-ne:'s, law enforcement agencies, insur~lJlce complUlies, TrailKuys, lIlotor Ucet ~:arety org,Uli:ations, and civic groups. :\0 d:lsq'oom theori s t, ~1r. Lofgren lws inVl'st igah'd on:1' 1,000 \'ehicle llL~C iden1:.; . He has conducted, und cont llmes to conduct, tests ',"1 tll \'L'hides nUlginf, in si:L' from lIIini-\..~ompacts to largl' tractor-trailor rigs. These tcsts involve lwhere appropriate) skids, critical scuffs, airbonK' tri,lls, \'chicle d;'11 Wllics, \.
5 ~onservatiOll or mOllll'ntullI, and weight shi rt on braking. j)r:nnng on his store of knowledge and practicll experiencc, :-h'. Lofgren has hTi tten a wealth of teaching materials, incl Udlllg a syllabus for aCL'idcnt inn.'stigation for use br Creyhoulld. lIe has authol'l'd articles that have appeared in police and traffic :-;afet)' j oumals ~l11d has re-celltly updatt'd his widely lLsed training text 1I:\;"JDBl10K FOR TIll: ACCIDE\7 RECU"JSTRlJCTl l1."JIST, adding in the 1983 edition a chapter deal ing in part h i th the overtuming 0 C \'chicles Oil curves. In thb IL\NDBOOK, ~h'. Lofgren lUldt.
6 'rscores--sometimes with a toucL of irony--the importmlCe of valid ACCIDENT reconstruction proceJures as a prerequisite for effective traHk ,Uld vehicle safcty legislation. M1'. Lofgren is President of the International Association of ACCIDENT Reconstruction Specialists. ---------------------~-~ ----~ -~-~~~--------------~ -----------~ .~~ ","' ..,_ '--__w '-'"'~ HANDBOOK FOR --''''11\ .. ~ .. --. ~" -'---w .. "!f~ -. -".. f ------:w r--I I -:. 1 I l~~ ]I ~J THE ACCIDENT RECONSTRUC1'IONIST By M. J. Lofgren {. PUBLISHED BY: ----------------~ ~-3RD (REVISED) EDITION COPYRIGI-IT BY M. J. LOFGREN.}
7 ALL RIGHTS RESERVED. NO PART OF THIS BOOK :MAY BE REPRODUCED IN PNf FORM WITHOUT PERMISSION IN WRITING BY M. J. LOFGREN. FIRST PRINTING SECOND PRINTING 2ND (REVISED) FIRST PRINTING SECOND PRINTING THIRD PRINTING 3RD (REVISED) FIRST PRINTING EDITION EDITICN 1976 1977 1977 1979 1981 1983 INSTITUTE OF POLICE traffic MANAGEMENT UNIVERSITY OF NORI'H FLORIDA 4567 ST. JOHNS BLUFF ROAD SOUTH JACKSONVILLE, FLORIDA 32216 PRINTED IN THE UNITED STATES OF AMERICA .~ _,~ A -~-. """-"""'--"'''1 "..~ ~ ,~ .., ~ - '4 ~" .. r" _ ..~ '''~ ,.---. ".~ -.~ ~ ACKNOWLEDGEMENTS An undertaking such as this is never the product of one individual, and I must recognize those who so significantly contributed to this endeavor: To Colonel.
8 JOJlleil C. Cltaw&oJtd and U. Colonel. GeJtald R. ~dge, Chief and Assistant Chief of the Minnesota State Patrol, who made the or::.ginal decision that a course in acci-dent reconstruction should be taught. To :the ThOO -<.n :the 6-<' with whom I have worked on accidents and who have supplied me with exhibits to use in teaching. 1bis :includes the Troopers who have told me, "Why the hell don't you go write a book or someth:ing!" To J. Bal?eJt, world-renowned ACCIDENT Reconstruc-tionist, author, and presently consultant for NorthwesteJTI University traffic Institute, who freely gave his time in shar-:ing with me his vast lmowledge and experience.
9 To the late Dh. K. ) 6malU1, former Director of Researdl at Northweste111 University traffic Institute, who spent countless hours in conference and correspondence with me. His letters on mathematical procedure and its adaptation to motor vehicles are a source that I will always be able to draw from. His passing left me with an empty sadness, and I will always re-member him. To Thad , Assistant Supervisor, Unit Course Brandl, Northwestern University traffic , who wrote the kitdlen recipe chapter on Remedial Math and graciously allowed me to use it in this manual . To this old friend and associate I am eternally grateful.
10 To my bho;thvL Lyle, who through the years has spent many nights and holidays trying to teach me hm" to derive f011nulas and without whose assistance this project would never have been possible. To Diane. ~ ; D.<. <. Hodge., and LegLLJt~I,-u, who have typed, edited, and illustrated for this manual . Without their splendid cooperation and durahility, none of this would have appeared in print. To my wine , who has put up with long field trips, insect bites, and cigar smoke and who has patiently listened to and helped solve problems and has dodged traffic on half the roads in this country holding the dangerous end of the tape for me.
