Standards & formats
Choosing Chapter 10 analysis software: what to check before you commit
Most Chapter 10 tools look alike in a demo. The differences show up on your own recordings: an edition the reader only half supports, a time reference it ignores, a 200 GB file it cannot seek. Here is what to check, and how to check it, before a tool becomes part of your process.
Why the choice is harder than it looks
Chapter 10 guarantees that a compliant reader can walk the stream. It does not guarantee that every tool decodes every data type, honours every edition, or replays channels in their true time relationship. Two tools can open the same file and draw different curves, one of them wrong, and nothing in the file will tell you which.
The cost of a poor choice is rarely the licence. It is the campaign spent trusting a plot that a better tool would have flagged, or the archive that turns out to be unreadable once the tool is retired.
Start with a test set, not a feature list
Before reading any datasheet, gather a few of your own recordings and run the same set on every candidate:
- A nominal flight, representative of your usual mix of channels.
- Your largest file: the one that takes longest to download.
- A recording with a known problem: a power cut, a lost time reference, a channel renamed after the setup was exported.
- Files from every recorder type in your fleet, including older editions of the standard.
- If you use live telemetry or Ethernet streaming, a capture of the live stream as well.
A tool that is right on the nominal flight and silent on the damaged one has told you more than any demonstration.
Twelve things to check
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| What to check | How to test it | Warning sign |
|---|---|---|
| Editions and data types | Open a file from each recorder and edition you own, and compare the data types decoded with those present | Channels skipped without a word, or shown as raw bytes |
| TMATS | Compare the TMATS the tool displays with the channels actually recorded | TMATS hidden, or trusted without any consistency check |
| Time base | Overlay two channels acquired at the same instant in different packets | Offsets that move when you change the display window |
| Time source | Open a file with a time-reference dropout | No indication of which source stamped which data |
| Integrity | Open your damaged recording | No warning; a gap drawn as a straight line |
| Avionics buses | Decode 1553 and ARINC 429 traffic message by message, with the labels of your ICD | Raw words only, or no message-level time |
| PCM | Decommutate a recorded PCM stream with your frame definition | No frame-sync status; a loss of lock goes unnoticed |
| Video | Play every codec your cameras write, next to the data | Video drifting away from the data over a long flight |
| Large files | Open your largest file and jump to its last minute | Every jump re-reads the whole file |
| Live streams | Receive a Chapter 10 stream over Ethernet, if you use one | Live mode sold as a separate product, or packets lost without warning |
| Exports and reports | Export a segment, then trace it back to file, channel and time | Exported values with no provenance |
| Offline use | Run the tool with the network cable unplugged | Features that stop, or files uploaded for processing |
Questions to ask the supplier
- Which editions of IRIG 106, and which data types, are decoded rather than merely read?
- On replay, does the tool follow recorded time or packet order?
- What happens with a file the tool does not fully understand: an error, a warning, or silence?
- Does any data leave the workstation, for licensing, usage statistics or processing?
- In which plain formats can the data leave the tool, and with what provenance?
- What does a seat cost, can a licence move from one computer to another, and what remains possible if it lapses?
Running the trial
- Install on a typical analysis workstation, not on the supplier's laptop.
- Run the test set on each candidate, in the same order.
- For each file, note whether it opened, how long it took, which channels were decoded, which warnings appeared, and one value checked against a known reference.
- Have the evaluation done by the person who will use the tool every day, not only by the person who will buy it.
- Keep the notes: if the tool is adopted, they become its acceptance record.
Licensing and long-term access
Flight-test data outlives tools. Prefer software that reads the open format directly, exports to plain formats such as CSV or KML without losing track of where each value came from, and works offline. Perpetual licences and subscriptions both have their place; what matters is knowing in advance what remains possible if a licence lapses, and keeping a plain-format export of anything you must archive.