# Data collecting and transmitting system

Discussion in 'Instruments / Avionics / Electrical System' started by Shabby, Dec 7, 2004.

1. Dec 7, 2004

### Shabby

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Hi my name is Shabby and I’m currently investigating the possibility of installing a wireless data transmitting system which extracts raw data from the FDAU/FDR and transmits them to a central computer (stationary).

I was looking on the Internet and found the Teledyne Wireless Ground Link (WQAR) and some other products, which has the same capability. However, the prices are extreme high to use them on small aircrafts

Therefore, I would like to know, if there is a cheaper (commercial off the shelf product) way to install such a device on the aircraft. For example just use of a GSM and a storage medium.

2. Dec 7, 2004

### Othman

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Hello Stubby,

I work with Flight Data Recorders (black boxes) every day. If you intend on putting an FDR system in a homebuilt, it may not be the most feasible way of doing what I think you’re trying to do.

1. The FDR and the DAU are simply too expensive, and the whole system will probably sum up to about the same price as your airplane.

2. The FDR is too bulky and heavy due to its crash survivability, probably not a feature you need.

3. Depending on the number of parameters you wish to record, and the bandwidth of the FDR you choose, data rates can be very limited.

4. You will require specialized tools/software (very expensive) to download and interpret the data which comes out as a binary bit stream in ARINC 717 format.

I have thought about a similar project in the past, but I haven’t gotten too far with it. The best thing is to assemble a system yourself, or find someone who’s knowledgeable with Data Acquisition Systems to help you out. I still believe that decent instrumentation system can be put together for light aircraft for about $10,000. You would need to instrument your aircraft with sensors for every parameter you wish to record, or find some way to tap into your existing instruments (you will still need to add potentiometers for mechanical type instruments). If you want to record attitudes and accelerations you would need a set of gyros and accelerometers. I saw an AHRS box that is suitable for the job for about$500US… I can’t remember the name of the company at this time. For accelerations, you can use good “non-aircraft” (cheaper) 3-axis accelerometer.

If the data is to be used for flight testing, the Data Acquisition System must be capable of recording each channel at rates between 16Hz to 64Hz. The storage of the data shouldn’t be a problem with tremendous storage capacities of modern disks.

There is so much potential in having an instrumentation system on an aircraft. The data can be piped to personalized displays on an LCD screen mounted on your instrument panel. The data can be stored for post flight analysis. Collecting data can help evaluate the health and usage of the engine and other systems, thus reducing over cost of maintenance and operation.

Actually, it would be a good idea to research what the UAV people are doing for data acquisition and telemetry. Focus on the smaller start-up companies (not NASA) because they generally find low cost solutions for their small operating budgets.

I hope I didn’t put you off your idea. I think it’s great, but it needs a bit of research to get all the right pieces together. But definitely doable.

3. Dec 7, 2004

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