Hi all,

 

Bonanza A36 - Real life - MF2020 and Ice

I live in cold weather, so last night flew the A36, 9 000 feet and at minus 3 everything frosted over.

there seems little to do n iMF2020 but go down until the air hits about 0 degrees.

Was my plane in jeopardy at that temperature or is it just nerve racking not to be able to see outside.

Also, what happens in real life. minus 3 is not very cold. I cant believe planes get grounded until it gets much colder.

Heck, I would not be able to fly 5 months a year.

 

Ron

 

 

 

You got wrong! It's not altitude and negative temperature. It's negative temperature and visible moisture IRL. In Asobo world they assume that combination of clouds plus negative C you get icing. It's partially true in real life. Also, temperature inversion such as warmer air above and rain while colder temperature below can also cause icing without a single cloud at current altitude.

Some interesting videos about icing conditions.

https://www.youtube.com/watch?v=yhC_M4N_p-E

Edited October 20, 20205 yr by OSM

And some people said the icing effects were too fast in MSFS!🤣

In real life you need a certain phenomenon called "supercooled water" to form icing on the airframe. It means that water must be present that is colder than 0 C but hasn´t frozen yet.

This is why ice in crystalline form (like snow) will not form icing on the airframe, it only becomes a problem after the plane has stopped on the ground and it can accumulate on top of it.

Supercooled water isn´t present "anytime there is visible moisture and T < 0". It is most prevalent in the range of 0 to maybe -15C, if it gets much colder the water usually freezes into crystalline form.

In addition - flying aircraft will "heat up" the air by pushing against it, this is called the ram rise, and the resultant temperature is the TAT or "total air temperature". It can be guestimated by subtracting 50 from your Mach number, so at .75 the ram rise is ca. 25 degrees C.

This is the reason why faster aircraft are normally not affected by icing so much - they fly fast in areas where supercooled water is present, so the ram rise renders it inconsequential.

Icing is more severe the more supercooled water is present - so it is strongest in cumuliform clouds which supports bigger droplets through its inherent lifting airflows.

I can´t say how often ice forms on smaller or slower aircraft (having mostly flown airliners), but in airliners the effect is fairly rare, even in the winter. It is so rare that most airliners can´t de-ice their stabilizers, the 747 can´t run wing anti-ice if flaps are extended and I think the A380 never had anti-ice for wings at all.

I would say it isn´t "going to happen for sure" even in light aircraft at negative temps and in clouds, although it is definitely more of a problem than it is for jets.

Cheers, Jan

1 hour ago, Ron Lefebvre said:

Also, what happens in real life. minus 3 is not very cold. I cant believe planes get grounded until it gets much colder.

As others have noted, there can be a lot of varied reasons for icing and it can happen in surprising conditions too. Doesn't have to be cold at all to have ice form on your aeroplane, in fact it could even be bright, very warm and sunny and you could still ice up under certain circumstances.

Already mentioned in this thread is the phenomenon of supercooled droplets of water which will freeze on contact with a metal surface such as a wing, and which are particularly hazardous to turboprop airliners and GA aeroplanes which tend fly at around at heights a few thousand feet either side of about 18,000 feet. This being where most rainclouds which exhibit this property are found - albeit not exclusively so. It is why regional propliners such as the ATR-72 have de-icing boots as well as heated surfaces, and they carry a very prominent ice accretion mast near the front cockpit window so there is an early indication of icing taking place. But...

You might be surprised on occasion to see jet airliners being anti-iced at the airport when it's actually not that cold at all, even when people working on the ramp are in shorts and t-shirts, which can seem odd. This is particularly the case for aeroplanes on a fast spin (i.e. a turnaround flight where the aeroplane is on the ground for an hour or sometimes less, typically many budget airlines).

The reason fpr that is Cold Soaked Fuel. This is where the aeroplane has been up at high altitude for some time in very cold air, then it has descended fairly quickly into the airport, whereupon it is turned around quickly and departs again. The danger with this, is that the fuel in the wing can get very cold indeed during the cruise (Jet A freezes at -40°C, Jet A-1 freezes at -47°C), so it is perfectly possible to have an aeroplane which has landed after having been up at 30,000 feet half an hour previously, which has fuel in the wings leftover that is very seriously below the temperature water freezes at, which makes the metal panels on the wings very cold indeed. This means if the aeroplane gets rained on, or flies through some moisture-saturated clouds, that water can instantly freeze on the wing even when the ambient temperature is well above freezing; it might even be really sunny and quite warm when this can occur.

So it's worth being aware if you ever see an aeroplane being either de-iced (or anti-iced) at an airport, that it might be for this reason. And in case you don't know the difference. De-Icing is when what is basically hot water with a bit of anti-freeze mixed in with it is sprayed onto the aeroplane to melt off ice which is already on there, whereas Anti-icing is when the aeroplane is sprayed with a slightly gloopy greenish-yellow fluid which sticks to the aeroplane skin and prevents ice from forming on the skin as a result of that, which is good for about 30-45 minutes after having been applied.

Ice is really complex (as you see from the above posts). In GA piston and SETP's it generally boils (like that?) down to visible precipitation and coupled with (flight surface) freezing temp. Rate of accumulation etc. and sublimation etc.  Have encountered it in warm air over the desert (carb induction) with zero precip/moisture on a sunny day. Some planes carry it better than others, and there is boots vs. TKS etc. Prop heat and windshield hot plates etc.

Your ? about being in 'jeopardy' needs answers to the above stuff first. Do you have boots? TKS? rate of accumulation? super cooled vs. rime vs. clear? As you can see this gets involved and the bottom line in small GA is if you encounter icing have a plan to escape - quickly 🙂

2 hours ago, 109Sqn said:

And some people said the icing effects were too fast in MSFS!🤣

Don't assume icing effects are correct due to a couple videos on Youtube. I've seen some discussions about icing from pilots and meteorologists recently and things like you see there seem to be rare and unusual. For the icing we see in MSFS to happen like it does is unrealistic I believe. 

Also, one of the issues in the sim as well, is that the setting for icing, to "Visual Only" is broken. I fly with the G36 all the time and any icing will cause it drop out of the sky, even with this setting. IMO, icing is broken all the way around and is poorly implemented as it stands. 

Edited October 20, 20205 yr by bahnzo

3 minutes ago, bahnzo said:

Don't assume icing effects are correct due to a couple videos on Youtube. I've seen some discussions about icing from pilots and meteorologists recently and things like you see there seem to be rare and unusual. For the icing we see in MSFS to happen like it does is unrealistic I believe. 

I wasn't suggesting that kind of icing is normal, merely saying that it is possible. I also said, right back when the speed of icing was first brought up on this forum, that I believed that the speed of icing was exaggerated for the entertainment value rather than outright realism, and done that way so that more people would experience it without having to take the find the perfect conditions for it to occur. As such, I think it is done very well.

5 minutes ago, 109Sqn said:

I wasn't suggesting that kind of icing is normal, merely saying that it is possible. I also said, right back when the speed of icing was first brought up on this forum, that I believed that the speed of icing was exaggerated for the entertainment value rather than outright realism, and done that way so that more people would experience it without having to take the find the perfect conditions for it to occur. As such, I think it is done very well.

I'd like to be able to pick between 'entertainment' icing and more realistic icing rates.  

The super fact icing is annoying when it happens at the end of a long flight quickly passing through a cloud layer.

2 hours ago, 109Sqn said:

And some people said the icing effects were too fast in MSFS!🤣

They are overall I'd say...and too slow to melt away.  That ice was melting away within minutes after he descended (and maybe has windscreen heat?)

If you are trying to fly realistically VFR you should not be flying anywhere near cloud cover VFR anyway.

In countries like Australia and the  US the restrictions for most airspace categories require cloud be kept at least 500 feet below. 1,000 feet above and 2,000 feet horizontal at all times.  Class B around major airports allows VFR so long as you stay clear of cloud. Class G day operations are similar unless your in a helicopter but allow clear of cloud under 1200 feet AGL. 

https://www.law.cornell.edu/cfr/text/14/91.155

IFR of course is another matter entirely.

First, I would like to thank everyone. Very informative.

I was flying IFR by the way. Cloud coverage was complete above 6 000 feet up to and beyond 9 000 feet.

Could not look outside the plane as it was completely covered in ice. Plane flew well. I did notice my speed drop quite a bit, but there was a lot of wind.

It sounds like I was just in the right buffer zone for it to happen.

I just cant be sure if the sim was just giving me eye candy with the windshield frost or if the plane was really icing up.

Just not many cues from flying inside the sim.

Would be nice to think the sim was able to simulate icing.

 

Ron

 

 

 

 

29 minutes ago, Ron Lefebvre said:

First, I would like to thank everyone. Very informative.

I was flying IFR by the way. Cloud coverage was complete above 6 000 feet up to and beyond 9 000 feet.

Could not look outside the plane as it was completely covered in ice. Plane flew well. I did notice my speed drop quite a bit, but there was a lot of wind.

It sounds like I was just in the right buffer zone for it to happen.

I just cant be sure if the sim was just giving me eye candy with the windshield frost or if the plane was really icing up.

Just not many cues from flying inside the sim.

Would be nice to think the sim was able to simulate icing.

 

Ron

 

 

 

 

Stay in it long enough and the plane won't be able to maintain altitude,Ive had it happen before in sim. As for icing IRL I look at the freezing level charts and stay at an alt below the freezing level. Flight into visible moisture ie a cloud will cause icing

1 hour ago, bahnzo said:

Don't assume icing effects are correct due to a couple videos on Youtube. I've seen some discussions about icing from pilots and meteorologists recently and things like you see there seem to be rare and unusual. For the icing we see in MSFS to happen like it does is unrealistic I believe. 

+1