Inside the Cowling Fire / Heat Detector?

[George Sconyers]

Does anyone know of detector available for small aircraft (not transport
aircraft / Part 135, 121) that can be installed in the cowling(s) to detect
the presence of some condition (excessive heat, IR, etc.) that would lead to
an in-flight fire? Examples of those conditions might include a failed
exhaust header gasket, loose exhaust component / fastener, growing hole in
the muffler or an exhaust pipe, or even a cracked cylinder.

A lot of real dangerous things can happen BETWEEN oil changes where they
could be easily spotted and it seems that such a detector could give a pilot
a much better chance of getting an airplane on the ground before a fire got
started by giving them some time to reduce power (which might prevent a fire
altogether) and head for the nearest airport to check things out. It sure
seems it might be several minutes that failures like those above could be
detected, and detected before they begin to catch things in the cowling on
fire around them.

I have done some checking and transport aircraft, some helicopters, and even
larger power boats have systems that detect excessive heat in their engine
compartments. Some discharge halon bottles, and some of those in boats even
shutdown engines (clearly not advisable on single engine aircraft).

Anyone know of an "affordable" and light weight detector for small aircraft
that might monitor the airflow near the bottom of the engine before it exits
the cowling or perform some other monitoring function to detect a condition
that could lead to an in-flight fire?

George

[George Sconyers]

I have done some work on this problem and was hoping to get some feedback
from the group.

Anyone have any idea what an acceptable price would be to an aircraft owner
for a cowling fire detection / prevention aid described as follows:

Aircraft Cowling Fire Detection / Prevention Aid:

- battery powered temperature sensor / transmitter module for placement in
the cowling.

- battery powered temperature receiver / digital display module for
monitoring in the cockpit.

- very small transmitter in cowling with a remote 400 degree F temperature
sensor that has a short braided wire cord and a 6" thin aluminum rod so it
can be easily positioned in the air stream exiting the cowling towards the
back of the engine somewhere along the bottom of the firewall.

- small receiver in cockpit (like little kitchen timers used for IFR
approach timing) displays cowling air temperature at the sensor and can be
set to alarm (blinks / sounds tones) when pilot selectable temperature is
reached.

- placed in the airplane by the owner, not connected to aircraft power
supply or other wiring, no permanent mounting bracket, just "stuck",
"clamped", or "wire tied" on just like a portable VFR GPS, portable VHF
radio, IFR approach (kitchen) timer, or a CD player not requiring a Form
337.

- sensor / transmitter, receiver / digital display / alarm, 4 AAA batteries,
combined weight less than 1 pound

- change AAA batteries at oil change / annual etc.

Any feedback on functionality or acceptable pricing appreciated.

George

"George Sconyers" > wrote in message
y.com...
> Does anyone know of detector available for small aircraft (not transport
> aircraft / Part 135, 121) that can be installed in the cowling(s) to
detect
> the presence of some condition (excessive heat, IR, etc.) that would lead
to
> an in-flight fire? Examples of those conditions might include a failed
> exhaust header gasket, loose exhaust component / fastener, growing hole in
> the muffler or an exhaust pipe, or even a cracked cylinder.
>
> A lot of real dangerous things can happen BETWEEN oil changes where they
> could be easily spotted and it seems that such a detector could give a
pilot
> a much better chance of getting an airplane on the ground before a fire
got
> started by giving them some time to reduce power (which might prevent a
fire
> altogether) and head for the nearest airport to check things out. It sure
> seems it might be several minutes that failures like those above could be
> detected, and detected before they begin to catch things in the cowling on
> fire around them.
>
> I have done some checking and transport aircraft, some helicopters, and
even
> larger power boats have systems that detect excessive heat in their engine
> compartments. Some discharge halon bottles, and some of those in boats
even
> shutdown engines (clearly not advisable on single engine aircraft).
>
> Anyone know of an "affordable" and light weight detector for small
aircraft
> that might monitor the airflow near the bottom of the engine before it
exits
> the cowling or perform some other monitoring function to detect a
condition
> that could lead to an in-flight fire?
>
> George
>
>
>

[Bushy]

If you want to keep the price down, and you are not worried about
certification, you could use a home oven temperature probe. There are meat
temperature probes from cooking equipment suppliers and actual oven
temperature probes available through pottery places for kilns.

Some of these are selfcontained and the probe could be placed in a sensitive
area and the cable fed through to the cockpit or cowl mounted gauge. The
cowl guage could be read via the windscreen, or a mirror.

Some of these can be set to a certain temperature to turn off the oven when
the meat is cooked. This could be used to operate an "Idiot Light".

Hope this helps,
Peter

[George Sconyers]

Thanks Peter! You are thinking right down the path I am currently on but
with a slightly different way to install it and to view the temperature.

So, if I negotiate with one of serveral existing manufacturers of an "oven
product" some of which I have already tested in my own turbocharged aircraft
to build it so it meets ALL the requirements of being in the cowling
(waterproof, electronics capable of handling the heat, etc. and some other
proprietary ideas...) and you could read your under cowl temperature on a
nice little digital display with an integrated "high temp" alarm in the
cockpit. What is the right price for a product that installs in 15 minutes
during your next oil change without running any wires through your firewall
or panel.

Anyone got an idea of what this might be worth to airplane owners?

$150?
$200?
$250?

Would this be something that pilot / owners would buy at their local pilot
shop or would the Internet be a more likely place to buy it, in order to get
a lot more info than can be put on the product packaging?

Interested in any thoughts anyone has on this.

George

[Jim Carter]

The oven or meat thermometers are usually direct contact. Early in your post
you mentioned an ability to monitor via infrared to spot gasket blowouts,
etc. I don't see how a direct contact device will provide that feature until
the fire has broken out and it is too late.

--
Jim Carter
"George Sconyers" > wrote in message
m...
> Thanks Peter! You are thinking right down the path I am currently on but
> with a slightly different way to install it and to view the temperature.
>
> So, if I negotiate with one of serveral existing manufacturers of an "oven
> product" some of which I have already tested in my own turbocharged
aircraft
> to build it so it meets ALL the requirements of being in the cowling
> (waterproof, electronics capable of handling the heat, etc. and some other
> proprietary ideas...) and you could read your under cowl temperature on a
> nice little digital display with an integrated "high temp" alarm in the
> cockpit. What is the right price for a product that installs in 15
minutes
> during your next oil change without running any wires through your
firewall
> or panel.
>
> Anyone got an idea of what this might be worth to airplane owners?
>
> $150?
> $200?
> $250?
>
> Would this be something that pilot / owners would buy at their local pilot
> shop or would the Internet be a more likely place to buy it, in order to
get
> a lot more info than can be put on the product packaging?
>
> Interested in any thoughts anyone has on this.
>
> George
>
>