Jump to content
Sign in to follow this  
Don t moderate me this way

Automatic operation of wing anti-ice

Recommended Posts

Ok guys I got some concrete info via the AMM (not my words) -----

 

2x ice detectors vibrate at approx 40,000Hz, and these will vibrate at a lower frequency when they collect ice. A heater turns on when the probe vibrates less than 39,867Hz. The heater stays on until the probe vibration returns to its usual value or the heater operates for 25 seconds. The usual time that the heater is on is 5 - 7 seconds, but if the heater is on for 25 seconds, the heater turns off and a fault condition is latched.

 

The detector has control logic that counts the number of heater on to off cycles.

 

If there are two or more cycles, and the airplane is in the air, the ice detector gives an engine icing signal to the ACIPS (Airfoil and Cowl Ice Protection System). The detector also gives an engine icing signal if the airplane is in the air and the heater is on for 15 seconds or more.

 

If there are ten cycles and the airplane is in the air, the detector gives a wing icing signal to the ACIPS.

 

The icing signals stay on until any of these conditions occur:

No ice for more than 3 minutes

The airplane is on the ground

The heater is on for 25 seconds.


Rob Prest

 

Share this post


Link to post
Share on other sites

Good stuff :-)

 

So Wing anti ice should stay on for at least 3min (after those 10 cycles and then no further detection).

 

In the mean time I have been try to accumulate ice with the PMDG.

 

I have tried at around 0C and up to -10 ground temps.

Resulting in TAT from +2 to -21C.

I have tried in Stratus clouds, in Cumulus and CB.

I have tried in Moderate and heavy rain and snow.

No Ice.

I have turned off window heat...also no ice on windows.

 

You guys sure ice can be simulated in FSX?


Rob Robson

Share this post


Link to post
Share on other sites

At FL300 over Canada SAT -56 TAT -26 above and below some cirrus, I turned on the AWI and L & R engine AI. The swithches stayed on never going back to auto. After 33 minutes I turned the switches off.

 

Michael Cubine

Share this post


Link to post
Share on other sites

Thanks all! Your references give me quite some insight.

 

I could create icing with

- Active Sky Evolution and searching for areas with CB

- and with the default thunderstorm wx theme, maybe additionally customizing/increasing the icing settings (towards 'severe').

 

Visual icing isn't included, neither in default FSX nor in the PMDG T7.

Share this post


Link to post
Share on other sites

Good stuff :-)

So Wing anti ice should stay on for at least 3min (after those 10 cycles and then no further detection).

In the mean time I have been try to accumulate ice with the PMDG.

I have tried at around 0C and up to -10 ground temps.

Resulting in TAT from +2 to -21C.

I have tried in Stratus clouds, in Cumulus and CB.

I have tried in Moderate and heavy rain and snow.

No Ice.

I have turned off window heat...also no ice on windows.

You guys sure ice can be simulated in FSX?

It is simulated, just very badly. The method for applying ice in FS9 and FSX is to increase the aircrafts gross weight, this happens very slowly, would hardly affect a Cessna let alone a heavy jet.


Rob Prest

 

Share this post


Link to post
Share on other sites

(...) If you do select WAI it will turn on briefly just to do a self test, it will then automatically disengage.

 

(...)

 

 

One more note:

The ground self test doesn't seem to be modelled (at least I didn't notice any indications of a test in process), so, IMO, this self-test mistakenly running in the air doesn't quite explain my findings.

 

Anyhoo, FS Captain accumulating ice weight doesn't seem to be a problem with the current T7 build: Ice weight is reset by FS Captain in intervalls, so the ice can't do any harm.

 

I would still prefer for PMDG to "tweak" the de-icing period and/or change the de-icing logic.   B)

Share this post


Link to post
Share on other sites

Just like on the Airbus the ground test is done behind the scenes, you won't be notified on the flight deck. These aircraft do many self tests without notifying the flight crew.


Rob Prest

 

Share this post


Link to post
Share on other sites

 

At FL300 over Canada SAT -56 TAT -26 above and below some cirrus, I turned on the AWI and L & R engine AI. The swithches stayed on never going back to auto. After 33 minutes I turned the switches off.

 

Michael Cubine

When you select ON....that is a manual setting. It will stay ON all day! The Automatic On/OFF mode is supposed to work with the switch/Switches on AUTO all the time.

Rob Robson

Share this post


Link to post
Share on other sites

 

 When you select ON....that is a manual setting. It will stay ON all day! The Automatic On/OFF mode is supposed to work with the switch/Switches on AUTO all the time.

 

 

So what I tried didn't prove anything at all. I must have missed the point of the whole thread.

 

Thank you

Michael Cubine

Share this post


Link to post
Share on other sites

  

So what I tried didn't prove anything at all. I must have missed the point of the whole thread.

Thank you

Michael Cubine

Hey, happens to the best :-)

Rob Robson

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

  • Tom Allensworth,
    Founder of AVSIM Online


  • Flight Simulation's Premier Resource!

    AVSIM is a free service to the flight simulation community. AVSIM is staffed completely by volunteers and all funds donated to AVSIM go directly back to supporting the community. Your donation here helps to pay our bandwidth costs, emergency funding, and other general costs that crop up from time to time. Thank you for your support!

    Click here for more information and to see all donations year to date.
×
×
  • Create New...