I'm wondering about how much CVR and FDR data an A320 (for example) would produce and at what intervals.

I believe that there are 4 or 5 voice channel and several sensor data things. I'm trying to get some data on commercial jets. Is there any place I could get some data on this?


3 Answers 3


The requirements for Flight Data Recorders (FDRs) on airliners like the A320 is in 14 CFR 121. For a good summary of the requirements for flight recorders in various types of aircraft, see the NTSB FDR Handbook.

Depending on the certification date of the aircraft (14 CFR 121.343), the FDR must record between 6 and 17 parameters. Since engine parameters are included, this could be up to 23 different parameters on 4-engine aircraft. Newer Digital FDRs (DFDRs) must record at least 88 items (14 CFR 121.344). Some of these parameters are conditional, and some require multiple parameters, so the total will probably be more than 88 parameters. The NTSB report on the US Airways 1549 accident notes that the FDR recorded 178 parameters during the flight.

According to this page, tape-based DFDRs can record at 64 12-bit data words per second. Newer DFDRs using solid state recording can store up to 256 12-bit data words per second. This 256 words per second is also specified in the information on this FDR. It says it can record >100 hours at 64 words/second, which translates to about 35 MB total. The parameters are per DO-160C standard, which you have to pay to access.

Accident reports will generally include readouts from relevant parameters, to give an idea of the items that are recorded. There is a table here showing some parameters, the measurement range, and recording intervals. The interval is anywhere from 0.125 seconds to 4 seconds depending on the parameter.

Aircraft may also have a Quick Access Recorder (QAR), which records many parameters (over 2000). However, aircraft are not required to have one and the QAR is not required to survive an accident. Airlines use them for data to improve operations, and they can also be used in less severe crashes for analysis.

  • $\begingroup$ thank you! very interesting 0.125 is along the numbers of what I heard, where did you come to that number though? but 3.1 kbit sounds a bit low?i heard something more along the lines of 5-6 how is that possible? apparently the DFDAU may generate much more data right? also how can i see how much the CVR would generate? (I trying to accurately simulate data transfers of fdr + and excluding cvr, but i don't have anything quotable yet) $\endgroup$ May 23, 2014 at 22:23
  • $\begingroup$ The 0.125 comes from the document linked in that section, there is a table with parameters and their intervals. I'll try to address you other questions in an edit later. $\endgroup$
    – fooot
    May 23, 2014 at 22:25
  • $\begingroup$ perfect thank you i'll need to read it properly! thanks a bunch $\endgroup$ May 23, 2014 at 22:25

From Wikipedia: Flight recorder

An FAA-standard flight data recorder will record a minimum of 88 parameters, sampled several times per second. An FAA-standard cockpit voice recorder will record four channels of audio.

  • $\begingroup$ there can be more parameters recorded but those are minima $\endgroup$ May 23, 2014 at 7:58

You can access the Honeywell website and download and read the manuals, brochures, drawings and schematics about connections of voice and data recorders. Honeywell is the largest manufacturer of black boxes for commercial, civil and military aviation.

Honeywell was among those who provided the black boxes for the A320 that crashed in the French Alps. There are many models and types of Flight Data Recorders (FDR) and Cockpit Voice Recorders (CVR), and they also record the status of other devices. There are many types of FDR's and CVR's whose characteristics depend on the type of aircraft and customer specifications.

  • 3
    $\begingroup$ Hello Luiz, and welcome at Aviation.SE. Please try to answer the question by including the information you can retrieve via the provided link. It is better to have the basic information here on the site and then have the link as reference. This is also helps in case the link breaks. BTW, I can't find any accessible manual and brochures there at first glance. $\endgroup$
    – DeltaLima
    Mar 25, 2015 at 22:50

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