A real nasty icing signature!

[Scott Dennstaedt, PhD]

If you are the type of pilot that uses a Skew-T as it relates to airframe icing, here's one that you should keep in your mind to avoid. Not a good afternoon to be flying a Mooney in the SLC area. 

[carusoam]

@Stetson20

Somebody put Scott D on your reading list....

Here is Scott D. Discussing the Skew T chart... used for icing info.

Also showing 50kt winds at Mooney altitudes...

Best regards,

-a-

[Mark89114]

You have an idiots guide to reading and understanding this?  Asking for a friend......

[Scott Dennstaedt, PhD]

16 hours ago, Scott Dennstaedt said:

If you are the type of pilot that uses a Skew-T as it relates to airframe icing, here's one that you should keep in your mind to avoid. Not a good afternoon to be flying a Mooney in the SLC area. 

 

Here's what got my attention.  

[GeeBee]

I would like to hear from the pilot. I recognize severe is aircraft dependent. I would like to know if the aircraft was TKS equipped. If not, if it was true severe icing I would think we would be reading about the crash. If it was TKS equipped I would like to know where it was building to categorize it as "severe".

"Severe: the rate of accumulation is such that ice protection systems fail to remove the accumulation of ice. Or, the ice is so bad it is on surfaces where you don’t normally see icing like aft of the protected surfaces (ie. past the de-ice boots or all over the spinner). Immediately exit from the conditions............severe icing is aircraft dependent, as are other categories of icing intensity. Severe icing may occur at any accumulation rate

[carusoam]

Urgent, severe, and M20...  surely grabs my attention as well!

Thank you Scott.

Delivering pertinent weather lessons in every post...

Is there a tail number signature with the pirep anywhere? Could be an MSer...

Best regards,

-a-

[Scott Dennstaedt, PhD]

Try reading this...

[exM20K]

19 minutes ago, Scott Dennstaedt said:

Try reading this...

Thanks for posting that excellent essay. 
I pulled up the FIP charts shortly after your first post and did see quite a bit of SLD marks in that area. Presumably the various icing models are built on the same measurements, and it’s very cool to see what goes into the sauce.

Do you have any plans to resume your in-person classes?

-dan

[GeeBee]

4 hours ago, exM20K said:

Thanks for posting that excellent essay. 
I pulled up the FIP charts shortly after your first post and did see quite a bit of SLD marks in that area. Presumably the various icing models are built on the same measurements, and it’s very cool to see what goes into the sauce.

Do you have any plans to resume your in-person classes?

-dan

You won't catch me going through a SLD forecast area!

 

[Scott Dennstaedt, PhD]

19 minutes ago, GeeBee said:

You won't catch me going through a SLD forecast area!

 

In this case there was no SLD forecast, that why I posted this case. It didn’t have any SLD signature, but represented a significant threat.   

[GeeBee]

What level of icing was forecasted?

Whoops, never mind, I see it now, Heavy. Does not seem like a good flight decision based upon the forecast.

 

 

[hammdo]

I have Scott’s book and Weather training course... great stuff!

-Don

[Scott Dennstaedt, PhD]

6 hours ago, exM20K said:

 I pulled up the FIP charts shortly after your first post and did see quite a bit of SLD marks in that area. Presumably the various icing models are built on the same measurements, and it’s very cool to see what goes into the sauce.

Do you have any plans to resume your in-person classes?

 

Dan,

If you are looking at the CIP/FIP icing severity charts (found on aviationweather.gov), the SLD isn't a calibrated probability and they will add the red-hatching on the chart even if it's as low as a 5% chance.  When I looked at the actual probabilities, the percentages were very low in this region. 

I don't have any plans to start my in-person classes back up again. They are extremely challenging to market and most pilots really don't want to pay for weather training. Sad, but true. They will pay top dollar for an engine management course since there's an immediate payback ($$$$), but becoming a safer pilot because you have more weather knowledge to minimize your exposure to adverse weather has no immediate monetary return.   

I tell everyone though, if you can get 20 or more people that have a serious interest in attending in your area, then I will be more than happy to travel to your location and hold one (post COVID-19, of course).  I've done that on several occasions where everyone prepays for the program and basically I show up and teach.  But every time someone leads the challenge and they get enough interested parties, the next challenge is for them to commit to a specific schedule and open their wallet.  The cheapest part of an airplane is the nut behind the yoke.     

[Scott Dennstaedt, PhD]

29 minutes ago, GeeBee said:

What level of icing was forecasted?

Whoops, never mind, I see it now, Heavy. Does not seem like a good flight decision based upon the forecast.

 

 

Agreed.  It was an area to avoid.

[carusoam]

2 hours ago, Scott Dennstaedt said:

Dan,

If you are looking at the CIP/FIP icing severity charts (found on aviationweather.gov), the SLD isn't a calibrated probability and they will add the red-hatching on the chart even if it's as low as a 5% chance.  When I looked at the actual probabilities, the percentages were very low in this region. 

I don't have any plans to start my in-person classes back up again. They are extremely challenging to market and most pilots really don't want to pay for weather training. Sad, but true. They will pay top dollar for an engine management course since there's an immediate payback ($$$$), but becoming a safer pilot because you have more weather knowledge to minimize your exposure to adverse weather has no immediate monetary return.   

I tell everyone though, if you can get 20 or more people that have a serious interest in attending in your area, then I will be more than happy to travel to your location and hold one (post COVID-19, of course).  I've done that on several occasions where everyone prepays for the program and basically I show up and teach.  But every time someone leads the challenge and they get enough interested parties, the next challenge is for them to commit to a specific schedule and open their wallet.  The cheapest part of an airplane is the nut behind the yoke.     

The Mooney Summit is a place where Mooney pilots congregate to Better the Bread... pick up some knowledge... and bump elbows... Tampa, off season...

I can invite @mike_elliott and @Seth to this thread...  these guys know something about how to schedule various presentations at the Mooney specific event...

PP thoughts only, not familiar with the inner workings of the summit...

Best regards,

-a-

[N201MKTurbo]

I was flying from Bellingham WA to Steamboat Springs CO once about 15 years ago. There was forecast severe icing and all the airliners were reporting severe icing at 15000.  Tops were at FL190. I filed for FL190 and was on top. 
 

It is good to have an airplane that is capable of getting you where you want to go, but it is kind of scary knowing that an engine failure means almost certain death.

[jetdriven]

37 minutes ago, N201MKTurbo said:

I was flying from Bellingham WA to Steamboat Springs CO once about 15 years ago. There was forecast severe icing and all the airliners were reporting severe icing at 15000.  Tops were at FL190. I filed for FL190 and was on top. 
 

It is good to have an airplane that is capable of getting you where you want to go, but it is kind of scary knowing that an engine failure means almost certain death.

To be fair here, if you're flying over mountains in a single engine airplane, regardless of icing, the outcome of engine failure is going to be the same

[mike_elliott]

7 hours ago, carusoam said:

The Mooney Summit is a place where Mooney pilots congregate to Better the Bread... pick up some knowledge... and bump elbows... Tampa, off season...

I can invite @mike_elliott and @Seth to this thread...  these guys know something about how to schedule various presentations at the Mooney specific event...

PP thoughts only, not familiar with the inner workings of the summit...

Best regards,

-a-

Scott was on the agenda for the Summit VIII we postponed, perhaps @Seth has him back on. I know Seth is busy putting this Summit together as the reins pass to the younger gen of Mooney pilots and will soon have the agenda up.

[gsxrpilot]

On 2/6/2021 at 7:03 AM, Mark89114 said:

You have an idiots guide to reading and understanding this?  Asking for a friend......

Let me try... and @Scott Dennstaedt will tell me if I'm close.

Where the Blue and Red lines merge in my Red Box... is IMC/Clouds.
The Green oval is the Pressure altitude.
The Blue arrow is the freezing level getting colder up and to the left.
The Magenta oval is the wind speed at those altitudes.

So we've got IMC between about 7500 ft and 15,000 ft. All of it's below freezing from about -5C to -20C. With winds from nearly calm on the ground to greater than 50 kts.

You'd have to climb through at least 7,500 ft of ice to get on top. 

 

[GeeBee]

21 hours ago, Scott Dennstaedt said:

Agreed.  It was an area to avoid.

Having been based in SLC for 6 years and flying into and out of it a lot the amount of moisture picked up by a system from the NW is huge as it passes over the lake. (after all where would Park City be without it) It is rare not to pick up ice into SLC during winter storm systems. Even the fog is highly moisture laden. The line had 6 P&W 2037s destroyed in one morning with freezing fog and the pilots not keeping up on their ground run ups to clear the fans.

 

 

[Scott Dennstaedt, PhD]

5 hours ago, gsxrpilot said:

Let me try... and @Scott Dennstaedt will tell me if I'm close.

Where the Blue and Red lines merge in my Red Box... is IMC/Clouds.
The Green oval is the Pressure altitude.
The Blue arrow is the freezing level getting colder up and to the left.
The Magenta oval is the wind speed at those altitudes.

So we've got IMC between about 7500 ft and 15,000 ft. All of it's below freezing from about -5C to -20C. With winds from nearly calm on the ground to greater than 50 kts.

You'd have to climb through at least 7,500 ft of ice to get on top. 

 

What you say is correct, but not what makes this so concerning.  Check out my post earlier in this thread for my analysis.  

[carusoam]

On 2/7/2021 at 5:21 PM, GeeBee said:

Having been based in SLC for 6 years and flying into and out of it a lot the amount of moisture picked up by a system from the NW is huge as it passes over the lake. (after all where would Park City be without it) It is rare not to pick up ice into SLC during winter storm systems. Even the fog is highly moisture laden. The line had 6 P&W 2037s destroyed in one morning with freezing fog and the pilots not keeping up on their ground run ups to clear the fans.

 

 

what happens to a P&W that a ground run-up solves its problem?

ice on the blades?

Best regards,

-a-

[GeeBee]

Yes, engine heat on a high by pass fan only solves lip and in some rare cases spinner anti-ice. What keeps ice off the fan blades is RPM. Which is why when you turn on engine heat in the air, engines usually go to a higher idle speed along with meeting bleed demands. Engine manufacturers specify ground run up procedures, usually every 15 or 30 minutes to 50 or 60% depending on the engine make and model to clear the blades. If you do not do this, when you apply power for takeoff both engines will FOD out, usually not at the same time which makes directional control "exciting".

In SLC I've had freezing fog ice the blades even before engine start, which creates a whole new procedure that has to be carried out by the mechanics. After you get the engines cleared, then you can start and taxi over to the de-ice stand.

The above applies to high by pass engines. Engines like the JT-8D you have to worry about the bullet getting heat since the EPR probe is located there and you become Air Florida.

[HXG]

Freezing rain hit the DFW area this morning. 

[HXG]

Here’s a NWS  link including SkewTLogP icing signatures:
https://www.weather.gov/jetstream/skewt_samples