New to Ancestry are 35,063 records summarizing each WW2 RCAF aircraft crash, many related to the British Commonwealth Air Training Plan. Here’s a case study showing how the card information can lead to details about the crash.
Above is the front of the card for a fatal crash near Ottawa’s Uplands Airport which took the life of D. M. Lord. From previous research I know he was an Australian and is buried at Beechwood Cemetery. The information from the card that the aircraft is Harvard 2884 is a big step toward finding the accident investigation report.
Entering Harvard 2884 at LAC’s Collection Search returns “Reference: RG24, Microfilm reel number: T-12345, File number: 1700-2884.” Digitized microfilm T-12345, available at Canadiana Héritage.
Accident investigation reports appear to be arranged on the microfilm by file number. Find the range of file numbers on that microfilm, find that by searching its number at LAC Collection Search, then use it to estimate how far into the 5,113 images of the microfilm that report can be found. As the length of the reports varies, it will be an approximation.
The file for the Harvard 2884 investigation is short, starting at image 943 and continuing to image 959. An average file is 56 pages, more than 100 pages is not unusual. The Harvard 2884 crash location was 2-1/2 miles south of Uplands Airport on the farm of Mr. Jervis Craig. While the cause of the accident was given as “obscure,” the relative inexperience of the instructor in instrument flying was suggested to be a contributing factor.
UPDATE: Paul Marsden points out that accident investigations start in 1919, before the cards available on Ancestry. For 1919-1945 they are almost entirely on microfilm, consisting of 4365 different investigations. They continue into the post-war period — there are 920 files, which are paper textual files, and tend to be much more detailed than the earlier files.
John, you might want to point out that not all the Aircraft Investigation Branch (AIB) reports were microfilmed. Some accident cards will lead you to a paper file in Directorate of Flight Safety (DFS) Series in the DND fonds. (DFS was the successor to AIB.)