Raven Flight Computers

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SammyD

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I've never used Raven products but now have about 20 of them (Raven 2 and Raven 3). Tell me if I'm understanding this correctly. With Main and Apogee plus programmable events 3 and 4 options, am I seeing four event outputs?

I have typically used PerfectFlite SL100 and CF altimeters, but they only allow for a single Apogee and single Main high-current discharge to light the e-matches, but the Ravens appear to be able to do it twice.

Disregarding the possibility of an altimeter failure (the reason I run two separate altimeters with separate power supplies), can ONE Raven be used to do a redundant dual-deploy system?

Thank you! S
 

SpaceManMat

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You can use one raven to provide some redundancy for duel deploy, it will provide redundant ematch and black powder. This is actually the default configuration.

You can also use seperate batteries for the altimeter power and the ematches. Anywhere from 2 to 5 batteries would be possible in that regards. The benefit is a battery failure only affects the ematch it is connected to. I’ve seen flights where the battery fails under the demand placed on it when the charge is fired, so it would protect you from that. If I was to do this I’d probably use a 3 battery arrangement with one battery for the primary ematches and one for the backup ematches.
 

rewilfert

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I just ordered 2 Raven 4s for my redundant setup. To me, the whole point of redundancy is to have 2 of everything. Two systems that can operate completely independent of each other and don't share anything. If you are using 1 Raven, then you have single point failures in your setup all the way up the altimeter itself. It would catch a bad pyro channel or igniter, but there are still other components in the system that can fail and take out everything.

If you look at the FIP screen here, you can see that all 4 channels can be configured similarly:

https://www.featherweightaltimeters.com/interface-program.html
 

SpaceManMat

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I just ordered 2 Raven 4s for my redundant setup. To me, the whole point of redundancy is to have 2 of everything. Two systems that can operate completely independent of each other and don't share anything. If you are using 1 Raven, then you have single point failures in your setup all the way up the altimeter itself. It would catch a bad pyro channel or igniter, but there are still other components in the system that can fail and take out everything.

If you look at the FIP screen here, you can see that all 4 channels can be configured similarly:

https://www.featherweightaltimeters.com/interface-program.html
This is true and generally how would do it. However we don’t usually have redundancy of chutes and harness, so it’s always a question of what level of redundancy are you comfortable with?
 

Buckeye

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Thank you! That's what I thought. Now, do I trust one Raven versus two of any brand/combination of altimeters and power supplies? :)
The question is do you trust yourself? One altimeter works fine and is very reliable. User error is the problem.

Oy, all this redundancy talk hurts my head. However, it is music to the ears of the altimeter makers!
 

SammyD

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I haven't had an altimeter failure due to user error as I check and re-check everything prior to flight. With that said, electronics are not 100% reliable, and redundancy helps to minimize the risk.......
 

manixFan

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I use both Ravens and Perfectflite altimeters. When I use redundant altimeters I use one of each. That way if it’s a failure mode due to the way the altimeter is programmed I have two separate types of programming logic behind the deployment events.

One thing I really like about the Raven is that there are so many additional mounting options for it. I have the 29 mm and 38 mm A/V Bays that Adrian sells, several Power Perches, and the simple circuit sold by Additive Aerospace. I am a big fan of the integrated magnetic switch in Adrian’s bays because it greatly simplifies installation.

For redundant altimeters I can fit a Raven and a Perfectflite, both with batteries, in the same space as a traditional altimeter and one 9 volt battery.

I know several fliers who use the inexpensive e-matches bought off eBay that they don’t completely trust, so being able to run to redundant e-matches off one altimeter is a nice confidence boost for a flight.


Tony
 

SpaceManMat

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Actually using 2 altimeters doubles chance of user error. Which may not necessarily lead to a failure, but some cases will (such as not imputing Mach lockout). For us reason I try to run my Raven as standard as possible.
 
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Craig Miller

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I just purchased a Raven 4 and can't get to connect with the FIP program. It auto senses the unit but just can't get past the trying to connect screen. I've tried different cables and ports with no luck. Any ideas...Thx
 

Cameron Anderson

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I just purchased a Raven 4 and can't get to connect with the FIP program. It auto senses the unit but just can't get past the trying to connect screen. I've tried different cables and ports with no luck. Any ideas...Thx
Make sure you've got a batt with at least 4 volts. I plug my Raven 4 in and after the initial beeps is when I push the connect button and it connects. I have found it is picky about the port and cable though so I found a set up that works and use it every time.
 

Craig Miller

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Thanks Cameron,
I have spent hours trying every possible combination and get the same result "waiting to connect".
I'm getting short on time. I want to fly this rocket for my L1 at Delamar in Nevada Memorial weekend. Adrian has not responded so I'm going to test fly this thing next week with the defaults and hope for the best...
 

Cameron Anderson

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Thanks Cameron,
I have spent hours trying every possible combination and get the same result "waiting to connect".
I'm getting short on time. I want to fly this rocket for my L1 at Delamar in Nevada Memorial weekend. Adrian has not responded so I'm going to test fly this thing next week with the defaults and hope for the best...
Is Delamar happening?
 
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