2 Altimeters 1 Switch

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Cory

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I built a redundant DD set up for my RW Formula 98 using a Stratologger as the primary event controller and a RRC3 performing as back-up, I have both altimeters wired to a single four pole, common rotary type switch. -

https://doghouse.blastzone.org/switches.html

https://lh5.googleusercontent.com/qXwCNHqebCk58qoO1a7Qg0R9i5F8bBbwAfZE7LsIh5k=w304-h171-p-no

I soldered all four attachment points to ensure no wire wiggle during flight could short any of the wires. I have used this setup only once for my L2 and all 4 ejection charges fired as intended, so I know it is possible, but I am not sure if it is advisable. I did all ground testing with one altimeter at a time operating, but verified both units could function simultaneously. The main reason for asking the question is I was unable to collect the data from the RRC3 even though it performed nominally, and I am grasping for straws as to why the data became somehow corrupted and ultimately unretrievable.

Any ideas/suggestions are much appreciated!
 
The switch wiring is not why the RRC3 data is corrupted, but I can tell you that you have not built a redundant system. In order to have a truly redundant system, you need to segregate both systems in their entirety. In your scenario, a switch failure leads to a complete recovery failure. If you had one switch per unit, dual switch failure is a lot less likely than a single switch failure, and more than likely you would have a successful recovery.
 
I built a redundant DD set up for my RW Formula 98 using a Stratologger as the primary event controller and a RRC3 performing as back-up, I have both altimeters wired to a single four pole, common rotary type switch. -

https://doghouse.blastzone.org/switches.html

https://lh5.googleusercontent.com/qXwCNHqebCk58qoO1a7Qg0R9i5F8bBbwAfZE7LsIh5k=w304-h171-p-no

I soldered all four attachment points to ensure no wire wiggle during flight could short any of the wires. I have used this setup only once for my L2 and all 4 ejection charges fired as intended, so I know it is possible, but I am not sure if it is advisable. I did all ground testing with one altimeter at a time operating, but verified both units could function simultaneously. The main reason for asking the question is I was unable to collect the data from the RRC3 even though it performed nominally, and I am grasping for straws as to why the data became somehow corrupted and ultimately unretrievable.

Any ideas/suggestions are much appreciated!
Wait a sec, are you using a dongle to get the data off of the RRC3?
If so, I am having the same issue with not being able to get data off. Please PM me if this is the case.
 
In order to have a truly redundant system, you need to segregate both systems in their entirety. In your scenario, a switch failure leads to a complete recovery failure. If you had one switch per unit, dual switch failure is a lot less likely than a single switch failure, and more than likely you would have a successful recovery.

Agreed, and good point. This was my first every av-bay, and I was unsure of how much play in the screwdriver existed when accessing the switch through the vent holes. I think I will probable modify the sled as suggested to accomplish true redundancy.
 
You also need to have dual batteries to make it completely redundant.
 
Is the RRC3 software connecting to the RRC3 successfully? Are you sure you're telling it to download the correct flight?

-Kevin
 
Is the RRC3 software connecting to the RRC3 successfully? Are you sure you're telling it to download the correct flight?

-Kevin

It connects fine, and I can pull off the factory loaded file of a simulated flight.
 
It connects fine, and I can pull off the factory loaded file of a simulated flight.

Cory -

There is no "factory loaded" file with the RRC3.

You mention that you "ground tested" each altimeter separately, so perhaps the data you are retrieving is said ground test? If you're able to successfully connect to the RRC3, validate the comms are truly operational using the Diagnostic Auto Loop operation. You can also use the Flight Simulator operations and a subsequent Flight Data Upload operation to validate data recording and retrieval end-to-end.
 
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There is no "factory loaded" file with the RRC3.

CORRECT!!! I had some time today, so I decided to view what I thought was the factory loaded file. VOILA - THE "MISSING" FLIGHT!!!

Before, I had assumed :bangpan: flight one was factory loaded since my ground testing did not include any vacuum setup and I had the option of Flight One and Flight Two, and I have only flown the altimeter once. I always tried to open Flight Two first, which would lead to a communication error that would shut down the mDACS application. I would re-open (without fully ensuring there were no lingering mDACS applications running in the background) mDACS and try to load FLIGHT 1 with the same result.

THANKS FOR ALL THE INPUT!!!
View attachment L2 Formula 98 as BACKUP FLIGHT.rff :grin:
 
CORRECT!!! I had some time today, so I decided to view what I thought was the factory loaded file. VOILA - THE "MISSING" FLIGHT!!!

Before, I had assumed :bangpan: flight one was factory loaded since my ground testing did not include any vacuum setup and I had the option of Flight One and Flight Two, and I have only flown the altimeter once. I always tried to open Flight Two first, which would lead to a communication error that would shut down the mDACS application. I would re-open (without fully ensuring there were no lingering mDACS applications running in the background) mDACS and try to load FLIGHT 1 with the same result.

THANKS FOR ALL THE INPUT!!!
View attachment 158969 :grin:


Cory -

Glad you were able to upload your real flight data. I'm currently revising the mDACS app to address all the little niggling issues reported since initial release. I hope to make it available in the next week or so. I opened your flight file and it looks great... I'm curious how you were able to ground test?
 
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Cory,

as others have said, that is not really a reduntant system. I would recommend a completely separate switch and power supply (battery for each altimeter).
 
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