Skip to main content

What the FAA doesn't teach about flying thunderstorms

By
I want to understand thunderstorms better. I stared learning about limitations of storm scopes which led me to more insights.

Before you attempt to fly close to, or through a front, learn about your front. Some fronts you can safely fly through, some you cannot.

Thunder cheat sheet

Preflight Tools
  1. Radar - locate active fronts, size, and direction of movement
  2. Sigmets - If your front is in a convective sigmet, you probably cannot fly through it. Airmets you generally can.
  3. Lightning - Look at lightningmaps.org to see how much "in past hour" and 'current" lightning there is. If there are no strikes or few strikes, even if you see heavy or severe precip, it's just lots of water, not much turbulence, likely not a powerful storm.
  4. Infrared Satellite - wunderground.com see how cold the reflection is. If temperature is -70, it's a very vertical storm, probably cannot fly through it.
  5. NOAA soundings - http://rucsoundings.noaa.gov/ to learn in detail about atmospheric makeup
In flight Tools
  1. Nexrad / ADSB weather - The "big picture" with 15 minute delay
  2. Strike finder - determine exact direction lightning in real time
  3. Strike Finder cell mode - Switch to cell detection mode when < 50nm from activity

Details about thunder storms

One problem is I used to rely heavily on nexrad radar alone. I assumed precip radar reflectivity directly correlates with storm intensity, but this is not true.  It's possible to have moderate or even severe precip that is just that - lots of water. Not much turbulence, no lightning. Lightning comes from vertical wind sheering, so when you have lightning, you KNOW there is bad turbulence. The more of it, the worse it is. Lots of water and no lightning? Probably fine to fly through or close to. So now I'm using radar reflectivity as just an initial cursory look and then watch the storm scope for activity. I also go to lightningmaps.org to see lightning activity before I fly, it tells me what my storm scope will see before I get up there. 

The more strikes and the more frequent the worse it is. Many of the discharges visible on storm scope aren't even visible lightning but still indicate turbulence

For example I"m watching a storm over NC right now. Top image is from lightningmaps.org bottom is aviationweather. Notice that the heavy precip over the water contains almost no lightning, yet, on radar, it looks like a severe thunder storm.

The lack of sigmet is a hint. And the top image shows "last hour of strikes". If I do current there is nothing over the water. The stuff over the mainland is really bad - stay away from there, give it 25nm, and fly the upwind side (east of the storm). The downwind side could still hammer you with huge balls of hail and cost you a $15000 paint job.

Inline image 3

Inline image 2

I'm also using soundings now. Super useful when flying to airports that don't report weather,also good to learn about layers and tops (since traditional reports only give you ceilings). And last but not least great to tell intensity of storm.

This is KILM now

Inline image 4

I see a massive drop in dew point at 14000' and _multiple_ temperature inversions, very unusual. A real monster, stay far away from that, definitely fly the upwind side of it or good chance of a hail shower even 20nm away.

Read the thunderstorm section form Weather Flying (pdf).
-Velocity of thundrestorm cell is telltale. 20kts is strong. 30kts is severe. 60kts is killer. This is not same as groundspeed of whole front.
-Look at cloud tops for "spilling" out of the tops. The more of it, the more active.
Hail comes out of the wash-off anvil cloud on the downwind side. It's full of fail and washes downwind. Instead, go around fronts on upwind side, and use 1nm for each kt of wind (20kts cell = 20nm around).

Comments

Post a Comment

Popular posts from this blog

How to get anything on EBAY for free (and get away with it)

By
This article explains how to get anything for free on Ebay. This is very simple, proven and guaranteed to work. You can get, for example, an IPhone 4, a 64GB IPad 2, or even a Macbook Pro laptop for free. 1. If the seller does not use delivery confirmation, you already won. Just tell ebay you never received the item. They will always side with you (bhe buyer) and refund your money, including shipping, AT THE SELLER'S EXPENSE. There is nothing the seller can do. Ebay will not investigate further, they close the case.  I have hard numerous reports of this happening.  See this facebook thread  and this article . The buyer now has no item, no money, and in addition he is out the cost of shipping. Totally screwed. 2. If you are dealing with a savvy seller, they will use delivery confirmation. Don't worry, you can still get your item for free. After you receive the item, open a case and claim the item broken. Let's use an IPhone 4 as an example. Open a claim and say the me...
10 comments
Read more

THE COPA CIRRUS SR22 PERFORMANCE REPORT

By
About this report This report was generated from data collected from 160 active COPA SR22 pilots. You can see the original survey here: http://tinyurl.com/sr22cruisesurvey . You can download PDF . Table of Contents What you will get out of this report Who were the pilots behind this survey What aircraft are counted in the survey Actual cruise speed and fuel flow Fuel flow vs TAS for NA lean of peak operations What is the most efficient altitude for NA SR22? Turbo SR22 performance at high and low altitudes Are TKS/FIKI planes slower? What is the fastest NA SR22 by generation? Who gets the best range? Are high hour NA SR22 engines slower and do they burn more fuel? How do LoP vs RoP performance compare? POH vs actual performance for NA Who is the fastest SR22? Conclusion About the author Frequently asked questions What you will get out of this report This report is for SR22 owners and buyers. How your SR22 performs compared to other SR22s How altitude affects perfo...
2 comments
Read more

How to hot start a Cirrus SR22

By
The SR22 does not like to normally start when the engine is hot. I use a simple procedure to hot start my SR22. My  Method 1. Prime 5 seconds 2. Throttle 1/4" open, mixture cutoff. 3. Start cranking and slowly advance mixture. 4. Once engine starts to fire, go mixture rich. Honestly I developed this through trial and error, I don't know exactly why it works but it does. I think this works because the prime step pumps cold fuel through the system to cool it down. Then cranking the engine with mixture cutoff pushes all the fuel and air bubbles out of the system, leaving room for clean fuel to be pumped in through cold fuel lies. CPPP Method At the 2015 CPPP in Williamsport we learned about another trick. Hot engine means hot fuel lines, which vaporize fuel (literally, fuel boils, air bubbles form). Engine doesn't want to start with part fuel part air being pumped in. You must cool down your fuel lines first. 1. Throttle closed, mixture cutoff. 2. Run boost pum...
1 comment
Read more