737-800 Cabin Altitude warning light on MIP...

[sagrada737]

I have a question on pressurization, and specifically on the MIP located "CABIN ALTITUDE" warning light indicator (red).

I understand that this warning indicator comes ON when ever the aircraft is not adequately pressurized, allowing the Cabin pressurization to exceed 10,000 ft.  This can be tested by climbing to an altitude of say 24,000 ft. and turning OFF the PACK switches.

Question:  In the 730-800, how long does it take for the Differential Pressure to reduce and the Cabin Altitude to increase above 10,000 ft.  allowing a condition where the CABIN ALTITUDE warning comes ON  - both in your Sim and in the real aircraft?

I'm wanting this information so I can further test my Overhead.  Feedback on this would be appreciated.

Mike

[Sam Llorca]

Hi Mike, I'm going to test it tomorrow Saturday morning, I will pm or call you with the results
If you can solve it before let me know please..
Cheers,
Sam

[sagrada737]

Hi Sam,

Thanks for testing this on your Sim.  It will be interesting to see what results you come up with.

As a practical matter, our Sims don't really have a Cabin to pressurize, but that's not quite the point - our Sims don't really have Landing Gear either, but we want to have it function.  Pressurization is certainly something in the background, a bit transparent to our typical Sim flight.  As far as our Sims are concerned, it will fly whether our Cabin is pressurized or not, so I'm not getting too distraught if the Cabin Altitude warning light doesn't come ON.  I just want to know how it's modeled and what parameter response I should expect.  Once I understand this, I'll put it behind me.

Thanks again for testing this today.

Mike

[andthiel]

Hi Mike and Sam

Please have a closer look here:

http://www.b737.org.uk/pressurisation.htm#Cabin_Altitude_Warning_Horn

(That's my favourite website for such kind of questions...)

Regards from Germany,

Andreas


Sent from my iPad via Tapatalk HD

[Sam Llorca]

Thank you for the link Andreas, good site.

[sagrada737]

Hello Andreas,

Thanks for the link.  I have reviewed this as well prior to asking my question regarding how long it takes for the CABIN ALTITUDE warning light go come ON after the PACKs are turned OFF at an altitude of FL240.

Hopefully Sam's testing will provide some data on this.

Mike

[Sam Llorca]

Hello Mjke,

I was testing the presuarization system for a few hours, packs off and all, unless I'm missing a step  your results are similar to mine,   It is not necessarily a bad thing, I rearely look or pay attention to this panel, it seems that this particular warning is not modeled. Hope this helps.

Cheers,
Sam