Date: Fri, 3 May 2002 13:00:18 -0600 To: Stacy Brodzik From: "John R. Daugherty" Subject: Re: P3 flight level tapes EXCERPTS FROM THIS EMAIL: You are probably already aware of this, but I'll go over it just in case. The standard tape consists of 6 types of records. After each project, the AOC flight director normally sends a printout of what these types are and what differences exist in the content of each of them for your particular project. That's part of the problem here, the contents of the records can change dramatically from project to project. Type 1 is the header record and contains 17 i2 words. It tells you basic things like the flight id, when they took off, when they landed, when the data was processed at the AOC, etc. Type 2 contains the coefficients needed to convert the raw data into scientific units. It is 202 F4 words. What is originally recorded can be power levels and things like that and these need to be translated into temperatures, etc. This is normally what takes the type 4 record and gives you the type 5 record. Type 3 is the data transformation record, essentially, it tells you where the decimal place goes in the type 5 records. There are 192 i2 words in this record. Type 4 is the original raw data recorded on the flight. There are 222 i2 words in this record, but they are packed into 10 word blocks, so there are actually 2220 i2 words. Type 5 is the converted data record, created in the post processing that results in the standard tape, or CD, nowadays. There are 106 i2 words in this record, packed into 10 blocks, for a total of 1060 i2 words per record. Type 6 is the trailer record. It contains many of items that are in the type 1 record, block out time, block in time, take off time, etc. There are 15 i2 words in this record. All of the records are i2 except for record type 2, which is F4. The first word in each record is the type of the record and the second word is the number of words/record. In working with Barry and Tom on this, Bob Hueftle and I have found some problems with the content of the type 2 records and Barry and Tom are trying to get that resolved. There is normally only one Type 1, 2, 3, and 6 record on the standard tape. The number of alternating type 4 and 5 records should correspond to the number of seconds in the flight. Hope this helps. What I am planning to do is to take the entire standard tape and put it into 6 files, one for each record type. The files for type 1, 2, 3, and 6 will be very short and should not change from flight to flight. Depending on the project, the header files for the type 4 and 5 records will be used to identify which of the records is used and not used, and for what variables, in a particular project. I then plan to write a netcdf file of each of these 6 files. After that, I plan to write a 7th file containing our position correction software results. Just how, or whether, to blend that in with the type 5 records in a common, or 2 separate netcdf files, hasn't been resolved yet. Mime-Version: 1.0 Date: Wed, 12 Feb 2003 13:40:20 -0700 To: Stacy Brodzik From: "John R. Daugherty" Subject: Re: Improve 2 standard tapes Hi Stacy, I installed a new disk this afternoon in my mac, so I was crashing around on my other disks sorting things onto the new disk and ran into something that may help. Here are the files they sent us for CALJet. I know that is ancient history at this point, but it should show you just what these files look like. A couple of abbreviations in here that might be of use, "cy" is for CALJet, "mp" is for MEaPRS, DPJ is Dave Jorgensen. I hope these help point you in the right direction. There are 14 files. I'll attach them to a couple of e-mails to get them all to you. JohnD