I was wondering about the use of both wing anti-ice and the engine in cold weather. I have a few questions.

 

I know the wing ice can use a lot of resources from the bleed air, created from the engines. Is it wise to take off with the bleed switches on and the anti-ice on? I know the Anti-Ice should be on after engine start were possible. The same question could be asked about the cowl engine.

 

How often should the AI be used on desent and final approach. Again bleeds on or off?

 

Joolsd

Hi Julian,

Some pretty common rules for 737NG icing operations:

Icing conditions exist when OAT (on the ground) or TAT (inflight) is 10C (50C) or below and visible moisture (clouds, fog with VIS less than one mile, rain, snow sleet, ice crystal, etc.) is present or standing water, ice , or snow is present on the ramps, taxiways or runways.

Engine TAI must be on at all times if any of these conditions are met.

This includes after start, takeoff, climb, curies, descent, approach and landing, taxi-in.

Wing Anti-ice must be on during ground operations between engine start and takeoff unless the airplane is protected by the application of Type II or Type IV fluid in compliance with an approved company OPSEC de-icing program.

Wing Anti-ice valves will close (Switch stays on) when takeoff thrust is applied. At lift-off the wing anti-ice switch trips off automatically because of the air/ground sensor goes into air mode. Turn the wing anti-ice back on if any of the above icing conditions exists.

During climb and Cruise engine TAI must be on during all flight operations when icing conditions exist or are anticipated, except during climb and cruise when the temperature is below -40C SAT. Engine anti-ice must be on prior to and during , descent in all icing condition, including temperatures below -40C SAT.

For light in-flight icing on wings, use the anti-icing as a de-icer, turn it on when ice builds up.

Extended flight in moderate to sever icing (holding), use anti-icing as an anti-icer (leave it on).

Note: Transport airplanes are not certified for flight into severe icing.

During descents, turn on engine TAI if icing conditions exist or are anticipated as stated above. Plan ahead. If engine TAI is used during descent, N1 will have a higher idle speed which will reduce descent rate.

Approach and landing use normal procedures and VREF's. If flaps 15 landing is planned, set VREF 15. If any of the following conditions apply, set VREF ICE = VREF +10.

- engine anti-ice will be used during landing

-wing anti-ice has been used any time during the flight

-icing conditions were encountered during the flight and the landing temperature is < 1

Brilliant thank you. I think that nails it.

Does FSX correctly simulate icing? Would the NGX (or any other PMDG plane) be effected in a scenario where icing conditions would (IRL) be present?

Does FSX correctly simulate icing? Would the NGX (or any other PMDG plane) be effected in a scenario where icing conditions would (IRL) be present?

The NGX does not simulate icing.

John,

 

Is there a difined point at which the application of a de-icer is required?

Hi Stephen,

De-icing and anti-icing applications would be applied anytime the airplane is contaminated with snow, ice , frost, etc., adhering to aerodynamic surfaces or there is the threat of persistent freezing precipitation during gound or flight operations.

CFR's established by the U.S. Federal Aviation Administration (FAA) prohibit takeoff when frost, ice, or snow adheres to airplane wings, propellers, or control surfaces. This is known as the clean airplane concept. The CFR's also prohibit takeoff any time that frost, ice, or snow can reasonably be expected to adhere to the airplane, unless the operator has an approved ground deicing/anti-icing program (OPSPEC's) that includes holdover timetables. In addition, the holdover times must be supported by data acceptable to the FAA. Holdover time is the time from when deicing or anti-icing fluid is applied to when it begins to fail (that is, when frost, ice, or snow begins to accumulate or readhere to a surface after deicing, anti-icing, or both).

On some day's, its obvious that de-ice/anti-ice operations need or will be in effect. Everyone's doing it prior to departure.

Some gray areas may arise though, but the final decision to apply de-ice or anti-ice fluid will remain with the captain and dispatch.

Is it going to be possible to use temp/dewpoint as a prediction within flightsim for the application of de-icer John.

 

Until such times as we get a sim that places snow on the wings!

Yes Stephen, since FSX lacks a structural ice simulation, for now you can use temperature and visible moisture, and a little imagination.

I was thinking more on the lines of the dewpoint figure dependant upon temperature.

The NGX does not simulate icing.

 

Try PMDG's J41...

There, yes, a climb w/ anti-ice on can take a while...

But as the tutorial states, that the every day experience of the turboprop jockeys.

 

Hmm, anything planned on icing for the PMDG triple seven?

The Jetstream's icing is limited to visual effect with no change in how the aircraft behaves...unless you have the Eng Anti-Ice on...in which yes...it takes a looooong time to get up to altitude..:sadface: