Does anyone know how to test an R-DAS?

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Well-Known Member
Feb 23, 2009
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New Jersey
I have an R-DAS that took a hit a couple months back.
Now I'd like to either fly it or sell it.

I did it once before, but have forgotten how I did it..

Testing the RDAS is pretty easy. You have two options:

Option 1: Smart Recovery

Verify that the RDAS is configured for smart recovery. Then hold it almost upside down and apply power. Wait a bit and then flip it right side up. It should detect launch. Wait a bit and flip it completely upside down. After a bit both the drogue and main outputs should activate. The main will be 0.25 seconds after the drogue. Connect type 194 light bulbs to the outputs.

Option 2: Timed recovery with breakwire detect.

Verify that the RDAS is configured for breakwire launch detect along with appropriate times for the events. Put a jumper on the breakwire detect pins. Then power up, wait a bit to verify it is running correctly, and pull the jumper. Launch detect should occor and then the outputs will activate at the programmed times.

You should also verify that the sensors are working. Download the "flight" data and look at it. Make sure that the altitude data isn't offset by unchecking the "Start altitude is" box in the Scale Settings (under the View menu item). Then see if the altitude shown is reasonable. It will not be exactly correct because of offset drift and such but it should be within a few hundred feet.

Also look at the acceleration data. If you did the smart recovery method, the acceleration should have a range of about 2G total. The zero value will depend on the exact orientation just before launch detect so this will not give you +1G and -1G. It will be more like +1.7G and -.3G depending on just how close to upside down you started. Also look at the raw value to make sure that they are around 512 +/- 20 or so. If you use the breakwire method, be sure to rotate the RDAS through 360 degrees so you have acceleration data to check.

Both sensors should show some random noise so make sure that is present as well.

The acid test is of course to fly it. If you are really uncertain about how well it is operating, don't connect ejection charges to it and just collect data. Be sure to record the digital event data or you will have no idea if the RDAS activates its outputs at the correct times.

This procedure is pretty much the same as in the RDAS User Manual with perhaps a little more detail.

It doesn't look like the people from R-DAS has done much in the past year to support their product.

I've been leaning towards selling it .

There was just an announcement on the RDAS list of several new developments...

A new video overlay board.

A new GPS board is in the works. The change is required because the old GPS chipset is obsolete.

A new 900 MHz telemetry transmitter.

The RDAS classic is being discontinued because of very low demand.