Can Anyone Identify

[Fly Boomer]

 

Can any of our Rocketeers identify this?  It's pretty far forward and under the turbo:

 

And two more (similar/identical) down low, starboard side, on the firewall:

 

 

Appreciate any help.

Thanks,
John

[EricJ]

Looks like a temperature sensor.

 

[Fly Boomer]

9 minutes ago, EricJ said:

Looks like a temperature sensor.

Thought about that, but why 3 of them?  Two are within inches of each other.

[carusoam]

Expect that the MP controller may want to know something about Temp and Press….

Looks like one of them is isolated with a piece of rubber…(?)

Where do the wires go?

See if @kortopates is around… (sensor question)

Best regards,

-a-

[Fly Boomer]

I'll head back to the hangar with my laptop, and get my endoscope out so I can poke around a bit -- I just thought it might be something common that someone with more experience would recognize immediately.  Darwin's boys didn't leave much unused volume forward of the firewall.

[carusoam]

Pics of all three sides…. 
 

with a coin for dimensions… 
 

Haven’t seen anything like it on my NA engines…

Best regards

-a-

[N201MKTurbo]

It looks like a fire detection system.

 

https://www.kidde-fenwal.com/Public/System_Details/Fenwal-Controls/DETECT-A-FIRE-Fire-and-Overheat-Detectors

Edited April 11, 2022 by N201MKTurbo

[EricJ]

3 hours ago, Fly Boomer said:

Thought about that, but why 3 of them?  Two are within inches of each other.

They might be being used as fire sensors.

 

[Fly Boomer]

35 minutes ago, EricJ said:

They might be being used as fire sensors.

Wow!  That was excellent.  Got this on the panel, but haven't tracked it down yet, and didn't make the connection.  I know this is tiny, but the light is labeled "FIRE DETECT" and the button is labeled "TEST"

 

 

[carusoam]

4 hours ago, Fly Boomer said:

Wow!  That was excellent.  Got this on the panel, but haven't tracked it down yet, and didn't make the connection.  I know this is tiny, but the light is labeled "FIRE DETECT" and the button is labeled "TEST"

 

 

Now the big follow-up question…

Is that a Rocket Engineering system, or something somebody added independent of the Rocket STC?

Turbo exhaust transitions and their V-Band clamps are known to have warmed things up under the cowling…

It is interesting that somebody had an alert mechanism for that excess heat situation…

PP thoughts only, not a mechanic…

Best regards,

-a-

[47U]

4 hours ago, Fly Boomer said:

I know this is tiny, but the light is labeled "FIRE DETECT" and the button is labeled "TEST"

I’m curious if the “TEST” switch checks the light only?  Or does it test the continuity of the detectors themselves? 

[David M20J]

1 hour ago, 47U said:

I’m curious if the “TEST” switch checks the light only?  Or does it test the continuity of the detectors themselves? 

Take what I have to say with a grain of salt but most platforms I have flown the test switch was to make sure the light was working so when the system went off you ACTUALLY had an indication and not just flying a long fat dumb and happy while your system is eating itself

[EricJ]

1 hour ago, 47U said:

I’m curious if the “TEST” switch checks the light only?  Or does it test the continuity of the detectors themselves? 

Sometimes that's the case, depending on how the sensors work.   Sometimes it checks the sensor continuity as well or other circuit functions.   Somewhere there should be a manual for that system that says what the test accomplishes.

[N9405V]

So, if you have a “fire detect” system, do you also have some type of suppression system?


Sent from my iPhone using Tapatalk

[David M20J]

Just now, N9405V said:

So, if you have a “fire detect” system, do you also have some type of suppression system?


Sent from my iPhone using Tapatalk

from my limited experience in small aircraft generally no for weight management, but there might a system I am unaware of, more for early detection so you can get down before it becomes a huge issue and unable to fly and/or see anymore.  Then again the only things Ive ever flown with fire suppression were 20k+ max gross

[47U]

2 hours ago, David M20J said:

Take what I have to say with a grain of salt but most platforms I have flown the test switch was to make sure the light was working

Hence my query.  The light doesn’t look like it has a ‘press-to-test’ function.  So, hopefully, FB Boomer is able to find the documentation on the system.  

Given the (visible) age of the detectors, I might try putting a heat gun on each detector and see if it will close the circuit.  Perhaps if the documentation is found it will provide guidance for continued air worthiness.

[A64Pilot]

Normally Fire detection sensors come in two flavors, one is a light sensor (flame detector) which I don’t think you have and the ones I’m familiar with can be tested with a red lens flashlight if out of the sunlight, but they have a whiteish lens on the end.

The other type is an overheat sensor, which is what I think you have, ones I’m familiar with have a gas in a tube very similar to a refrigerator thermostat and read that gasses pressure. That one could be tested with a button as it was checking to see if there was gas pressure below the alarm threshold of course.

There should be paperwork in the book telling you what system you have. I assume yours is there to detect an exhaust leak and is an overheat detector.

I would find paperwork that should tell you the type and hopefully ICA data, (Instructions for Continued Airworthiness) that should give you all the information you need, personally I wouldn’t try any kind of test until I read that ICA, maybe the detectors are a one shot deal?

Edited April 12, 2022 by A64Pilot

[Fly Boomer]

 

All excellent questions.  This is what makes MooneySpace so great -- even if you don't get the answer immediately, you get ideas that lead to the answer.

IN ORDER:

1. If it was installed by Rocket Engineering, I can find no paperwork on it.

2. They do appear to be strategically placed where an exhaust leak is likely.

3. After @EricJ turned on the light for me, I spent the rest of the day researching the Internet and, as @David M20J suggested, some similar systems only test the light.  That said, I found nothing that looks exactly like what I have.

4. No fire suppression that I can see and, as was pointed out, probably because of weight.

5. Finally, as @A64Pilot suggested, my research leans toward a plain heat detector because there is no window on the detectors for infrared or ultraviolet, but I'm loath to do any testing until I learn more about the system.  Pursuant to several replies, so far there was nothing in the STCs, 337s, etc. that I got from the FAA; nothing in the logs, receipts, loose documentation, ICA, no AFM supplement ... zero.

I really appreciate everyone's help and suggestions.

 

[Fly Boomer]

19 hours ago, N201MKTurbo said:

looks like a fire detection system.

Thank you!  I just got back on MS, and didn't page all the way up to the top, and initially missed your response.

I did look at some Kidde/Fenwal systems during my research yesterday, but I didn't see the one you found.  Maybe not identical, but very similar.  I'll reach out to Kidde/Fenwal to see if they know of an older version of those detectors.  This is the most promising example I have seen of a current system that's quite similar to mine.
 

[EricJ]

1 hour ago, Fly Boomer said:

Thank you!  I just got back on MS, and didn't page all the way up to the top, and initially missed your response.

I did look at some Kidde/Fenwal systems during my research yesterday, but I didn't see the one you found.  Maybe not identical, but very similar.  I'll reach out to Kidde/Fenwal to see if they know of an older version of those detectors.  This is the most promising example I have seen of a current system that's quite similar to mine.
 

There are a bunch of different kinds of fire detectors, and naturally they're all a bit different from each other.   Those look like they're probably either switches or thermocouples.   For both types usually the test switch tests a bit more than just the light, but you'd need the manual or something to know for certain.   These figures are from FAA-H-8083-31A, and shows what the test button does for both switch and thermocouple type.   I think what you have are most likely switches.

[Fly Boomer]

10 minutes ago, EricJ said:

 I think what you have are most likely switches.

Thanks.  I would expect it to be the simplest system.  I've never seen this on a piston single before.

[Will.iam]

Maybe disconnect one of the sensors and see what the light does before and after a test since if it was testing continuity that should fail with one or all three of the sensors disconnected?

[Fly Boomer]

7 minutes ago, Will.iam said:

Maybe disconnect one of the sensors

That's a possibility, but I'm beginning to suspect that the detectors are normally open, and close when they detect heat.

 

[Will.iam]

8 minutes ago, Fly Boomer said:

That's a possibility, but I'm beginning to suspect that the detectors are normally open, and close when they detect heat.

 

Ohm test on sensor would verify that and if so at least you could short the connector wires to at least see the light go on and test the wiring harness as well as any audible alert if it has one?

[carusoam]

Of the two test circuits posted by Eric above…

1) Is a fast test… push button, get light…

2) Is a slow test… push button, wait for system to warm, get light…

+1 just read the directions - E. Musk

Additional thoughts…

Rocket Engineering still answers the phone when they want to…

Fire suppression systems will have a canister, hoses, and spray nozzles… hard to miss.

PP thoughts only,

-a-