Hamming Code and Page Parity Checker

This program checks the Hamming code and page parities of the raw Flight Data Recorder (FDR commonly called "black box") files that were read from Loral Fairchild Model F-2100 FDRs. It is a modification of the program that checks the FDR file for American Airlines Flight 77 (AAL77) which was read from the same make and model of FDR. Incorrect Hamming codes and page parities indicate data that has either not been recorded correctly or not recorded completely or has been corrupted after it has been recorded.

I have checked six FDR files for problems which can be downloaded from here. Details of the FDR files are as follows:

The file American 77.fdr is the FDR file from AAL77 which I received in this Freedom of Information Act (FOIA) request to the United States National Transportation Safety Board (NTSB) and is the only one of the six FDR files that has incorrect Hamming codes and page parities.

The two files DCA02MA001_AAL587_ALL.fdr and DCA07MA310_AALengOct07.fdr are the two FDR files which I received in this FOIA request.

The file UR-DWH from RUAG Raw Data.FDR is an FDR file that I received from a first source other than the NTSB that has kindly allowed me to make it publicly available.

The two files 0410992L.FDR and PRUEBA.FDR are two FDR files that I received from a second source other than the NTSB that has kindly allowed me to make them publicly available.


You can download the output text file generated by the program from here.

You can download the text headers of the FDR files from here.

Information about the format in which the FDR records the data can be found in this post and in figure 4.2-2 of this document.

You can download the C# source code of the program. I used Microsoft Visual C# 2010 Express Edition to create it. You can look at the .cs source files using any text editor, and you can download the Microsoft Visual C# 2010 Express Edition from Microsoft to compile it. Alternatively, you may be able to get a DVD with the Visual Studio Express Editions from your local Microsoft sales office.

As I am providing this program free of charge, it is provided as is.

I take no responsibility for what the program does or doesn't do.

However, you can email feedback to me (Warren Stutt).

A Change Log detailing the changes in different versions is available here.

Back to Warren Stutt's Home Page