Thunderstorm avoidance

[Aztec Driver]

Fledgling charter pilots are constantly pushing their comfort levels and boundaries, attempting to learn all that they can and be a more proficient, more capable pilot. Having been a co-pilot for quite a while, and observing and learning from more sage pilots than myself, I have been in some close quarters with thunderstorms on several occasions, much closer than was my comfort levels, and certainly closer than the suggested amounts.

Armed with this experience, as well as a strikefinder and XM weather, I was gifted one night with a Lifeguard flight for needed body parts for a life saving operation. There was no weather at my origin airport, but my destination was being slowly encased in moderate to heavy precipitation with moderate to severe thunderstorms all over the area. XM showed a horseshoe area of little to no precipitation surrounding the airport of destination just about the time of my arrival to the south. I had just traveled south of the large reaching area of thunderstorms and precipitation for the last 45 minutes in the clear. The area that was around the airport was reasonably clear of precipitation and that was my flight plan. Lightning was frequent and intense all north of my location. ATC attempted to turn me north to the airport earlier than my flight plan called for, but after a brief turn toward that direction, I let them know that wasn't going to work.

Following my original flight path, which XM still showed reasonably clear, and staying visual, I flew through some moderate shower activity, accompanied by some moderate bumps, and intercepted the localizer for the airport. There was some very intense lightning just north of the localizer, and I was happy to know that those storms were moving east, not south, and I was soon delivering my package to the courier.

Knowing that there were more storms looming, and seeing that there was some lightning activity to the southwest, I decided that this was a good time to vacate rapidly the way I had come in. I dialed up the XM and refreshed it, seeing that the hole I had come in was still there, although a little more clogged than it had been. I got my clearance and off I flew. The controllers were great, directing me back the way I came. There was frequent and intense lightning all around me, but I was in the clear and proceeding through the only hole in the 500 square mile area.

On the off chance that I would fly into some serious turbulence, I had powered back to maneuvering speed. Suddenly, alll the lights on the ground disappeared, and a wall of water slammed into the airplane. There was lightning on both sides of the aircraft, and very close. The entire plane shook enough for the instrument panel to become a blur. Everything in the cabin was airborne, turning the entire airplane into a giant mess. I lost 500 feet before it finally subsided. I climbed back up to altitude and steadied it out again, just as the controller comes back on and asks if I am still with him. I think I weakly replied affirmative.

I was just as quickly in the clear again and south of all of the mess again. The controller says its clear the rest of the way, to which I replied, "that's good, because I don't ever want to do that again."

Some lessons learned.

1. If you use XM weather, at least zoom it in so you can actually see the red-purple cell you are about to penetrate.
2. Make sure your seat belt is really snug.
3. Watch the storm from the ground, it's a lot safer. Although it is pretty to watch from the air.
4. Drink all sodas to completion before departing. This saves cleanup in the event everything goes airborne.
5. All seat covers should be made of vinyl backed material, to catch afore-mentioned puddle of soda to aid in cleanup. This was the one thing I did right.

So happy to have lived through this. It wasn't the worst turbulence I have been in, and it wasn't plane twistingly bad, it was just scary as all get out, because I know it could have been.

 

[jesse]

That is the sort of stuff you can only do so many times. Hopefully the experience will be remembered.

 

[dmccormack]

Wow.. no fun!

A few weeks ago I was leaving CRE and upon radar contact controller issued "030 for traffic avoidance."

A glance at the XM and Stormscope -- "Unable"

"OK.. then..maintain 4000."

We were in IMC and without those two complimentary pieces of hardware, would not have launched.

But it was a great comfort to know where the Red was and where to go to avoid it.

 

[tonycondon]

XM really cant be counted on for that sort of manuevering through storm cells. the latency in image delivery makes a big difference.

 

[Lance F]

Good post, thanks. Two questions. We all understand the delay from the XM NEXRAD, but didn't your stormscope give any warning of the cell? What altitude were you at?

 

[ScottM]

Suddenly, alll the lights on the ground disappeared, and a wall of water slammed into the airplane. There was lightning on both sides of the aircraft, and very close. The entire plane shook enough for the instrument panel to become a blur. Everything in the cabin was airborne, turning the entire airplane into a giant mess. I lost 500 feet before it finally subsided. I climbed back up to altitude and steadied it out again, just as the controller comes back on and asks if I am still with him. I think I weakly replied affirmative.

This is why it is best not to have leather seats but something that is a bit absorbent!!

 

[dmccormack]

Good post, thanks. Two questions. We all understand the delay from the XM NEXRAD, but didn't your stormscope give any warning of the cell? What altitude were you at?

Exactly -- StormScope + XM + Flight Service Calls + Eyes out the window = Situational Awareness.

 

[Ken Ibold]

Good post, thanks. Two questions. We all understand the delay from the XM NEXRAD, but didn't your stormscope give any warning of the cell? What altitude were you at?

Perhaps it was just time for this cell to bloom into something active. Maybe there was nothing for the stormscope to paint until he was in it. BTDT myself.

 

[tonycondon]

Exactly -- StormScope + XM + Flight Service Calls + Eyes out the window = Situational Awareness.

On this flight I had a few weeks ago, I found that the info from KC Approach was a satisfactory substitue for FSS/Flight Watch. Although Approach controls weather radar capabilities are typically better than centers. On board radar helps too, but I didnt have it for that flight.

 

[dmccormack]

On this flight I had a few weeks ago, I found that the info from KC Approach was a satisfactory substitue for FSS/Flight Watch. Although Approach controls weather radar capabilities are typically better than centers. On board radar helps too, but I didnt have it for that flight.

Right -- it's good to ask if the APP has WARP or just ASR. WARP will provide a NEXRAD image overlay.

(Though I don't know what the latency is for them as opposed to commercial NEXRAD... Scott??)

Myrtle Beach Approach control doesn't have WARP -- I hear a Socata say, "Thanks for the help, Myrtle, but our radar is better than yours so we'll fly heading 120 if that's ok..."

 

[ScottM]

(Though I don't know what the latency is for them as opposed to commercial NEXRAD... Scott??)

Not sure either. I have seen some feeds that are close to real time, perhaps a minute or two off. XM seems to have the longest delay.

 

[dmccormack]

Not sure either. I have seen some feeds that are close to real time, perhaps a minute or two off. XM seems to have the longest delay.

Really?

Hmm.. so far I haven't seen any longer than 00:05 on the XM delay indicator on the 496.

But looking out the window and comparing the painted image with the visible dark cloud, there is clearly a delay.

I use a 30 nm buffer, so it would have to be some delay to be here when it's really there.

 

[ScottM]

Really?

Hmm.. so far I haven't seen any longer than 00:05 on the XM delay indicator on the 496.

But looking out the window and comparing the painted image with the visible dark cloud, there is clearly a delay.

I use a 30 nm buffer, so it would have to be some delay to be here when it's really there.

That is why XM is better at strategic decision and when you couple it with the real time storm scope you have a really good idea of what is going and can make quick tactical decisions.

 

[gismo]

Really?

Hmm.. so far I haven't seen any longer than 00:05 on the XM delay indicator on the 496.

But looking out the window and comparing the painted image with the visible dark cloud, there is clearly a delay.

I use a 30 nm buffer, so it would have to be some delay to be here when it's really there.

That's only the time from when your 496 received the data, there are several more delays including the time it takes for the NEXRAD sites to make several sweeps, transmission time from there to XM's weather provider, time to integrate all the images together, and time to uplink and downlink the image to your 496. The NEXRAD sites are not synchronized to each other so it's easily possible that the data you just received came from 5-10 (10 would be rare IMO) minutes of actual collection by a radar site.

I've done a fair bit of comparing XM NEXRAD with onboard radar and eyeballing. It seems to me that your 30 nm is about right. Just remember that storms evolve as well as move.

 

[dmccormack]

That is why XM is better at strategic decision and when you couple it with the real time storm scope you have a really good idea of what is going and can make quick tactical decisions.

Exactly right -- I've been very pleased with the combination -- I think either singly would be too much reliance on a single point of failure.

 

[tlglenn]

I spent last night in El Paso, Texas and the previous night in Cavern City, New Mexico playing it safe. I'd like to convince my flying club to invest in some weather gear for the planes, but only some of us fly IFR.

 

[dmccormack]

I spent last night in El Paso, Texas and the previous night in Cavern City, New Mexico playing it safe. I'd like to convince my flying club to invest in some weather gear for the planes, but only some of us fly IFR.

A handheld XM unit plus calls to FSS would serve well, especially in areas of widely scattered -- much easier to circumnavigate those by a wide margin.

 

[tlglenn]

A handheld XM unit plus calls to FSS would serve well, especially in areas of widely scattered -- much easier to circumnavigate those by a wide margin.

I've been using FSS in-flight, but it's not quite the same as seeing the picture with your own eyes. I'd like to get Stormscopes in our Garmin 430-equipped planes. Even the VFR pilots might buy into it given the summer afternoon weather in Arizona. I've thought about getting a Garmin 496, but I have other budget priorities.

 

[dmccormack]

That's right Tony. The ASR-9 or ASR-11 (approach control) is a Doppler fan-beam radar that has a "weather channel." Many years ago, I helped build some of the software for this portion of the radar. Not only does the radar pick up aircraft, it also can detect hydrometeors we call rain drops. The radar makes a turn every 4.6 seconds and updates quite rapidly although the weather channel doesn't update that fast - it's on the order of 1 minute. I know when approach control gives me advice, I have a very current image. That doesn't mean I will take their advice...it depends on what I see outside of the cockpit that matters the most.

Is there a key to determine which DEP/APP has ASR-9 or 11?

It would be useful to know if the approach you're flying into has better or worse picture than XM NEXRAD provides...

 

[dmccormack]

Dan,

Both of these radars are similarly equipped, so it doesn't matter. What matters if they also have a Terminal Doppler Weather Radar (TDWR) at the airport (actually it's off the airport 6 or 7 miles) or they use the poor man's version called Weather Systems Processor (WSP). The key element here is that while the ASR can show the "returns" the TDWR provides alerts associated with potential wind shear, gust fronts and microbursts. WSP does the same thing, but isn't based on a separate radar system, it takes its feed from the ASR weather channel.

Is there a way to know if approach has TDWR or WSP or not? Or simply ask "Are you WSP equipped?"

 

[wsuffa]

Wow.. no fun!

A few weeks ago I was leaving CRE and upon radar contact controller issued "030 for traffic avoidance."

A glance at the XM and Stormscope -- "Unable"

"OK.. then..maintain 4000."

Lucky. I was arrlving at ARR one night and Chicago was NOT authorizing deviations for folks that were picking up ice. One tried the "unable" line and was promptly given "immediate turn 180 degrees from present heading, state intentions."

I've done a fair bit of comparing XM NEXRAD with onboard radar and eyeballing. It seems to me that your 30 nm is about right. Just remember that storms evolve as well as move.

Me, too. That's why I use the XM as a tool - and why you've got to use it over a period of time to visually track the cells.

See my note in Ted's thread about a couple of real-life stories of using XM (with other tools) to avoid.

 

[dmccormack]

Lucky. I was arrlving at ARR one night and Chicago was NOT authorizing deviations for folks that were picking up ice. One tried the "unable" line and was promptly given "immediate turn 180 degrees from present heading, state intentions."

If I was given a heading into severe weather, and was refused, I'd repeat "unable," pick up the safe heading and deal with them later.

Better to battle with bureaucrats alive on the ground than testing out how much punishment a 40 year old airframe can stand.

 

[Ted]

I had missed this topic. Bryon, I'm glad you made it through. Sounds like an intense ride.

 

[Aztec Driver]

Sorry, no time to post recently.
I was at 5000 and, yes, my stormscope was registering all over the place. Unfortunately, it seems to register with any reasonably heavy rain, as I have seen before. I was attempting to maneuver around the highest concentration of "strikes".

I definitely learned a lot from this flight. Although there is a definite lag and learning curve for the XM, I find it reasonably accurate for the weather that I normally traverse in. I don't go looking for thunderstorms, and I usually steer well clear of them, but I sometimes clear them by just a few miles, which is what I was trying to do that night. I believe if I would have zoomed the XM to the proper zoom level, and also set the stormscope to a smaller range, I might have seen the cell that was close to me a little sooner than penetrating it. I still had a sizeable hole to escape, I just didn't see the cell in the middle of that hole until it "found" me.

 

[Ted]

One thing my flight instructor says is that he's never seen a stormscope give him a false negative, just lots of false positives, so part of the method he employs is flying in the direction where there's no strike activity.

Of course, if the whole thing is lit up, then it becomes a matter of "Well ****, now what?"

 

[wsuffa]

One thing my flight instructor says is that he's never seen a stormscope give him a false negative, just lots of false positives, so part of the method he employs is flying in the direction where there's no strike activity.

Of course, if the whole thing is lit up, then it becomes a matter of "Well ****, now what?"

good thing most of the falsies on my stormscope show toward the rear of the airplane....

 

[dmccormack]

Of course, if the whole thing is lit up, then it becomes a matter of "Well ****, now what?"

Turn it off, of course.

B)

 

[Ken Ibold]

One thing my flight instructor says is that he's never seen a stormscope give him a false negative, just lots of false positives, so part of the method he employs is flying in the direction where there's no strike activity.

He has not flown with a Stormscope enough, then. It is very possible to fly into a cell that is just reaching the point where lightning begins -- so there has been no activity for the Stormscope to pick up until you are in the wrong place at the wrong time. Perhaps that doesn't meet the strict definition of a false negative, but in practical terms your bacon is just as much on the line.

Multiple tools + multiple views = information you can use to decide where to go. XM weather, eyeballs and stormscope combined are fairly good.

Ted, the other thing you need to consider as you do you IR training and then start to use it is that many, many instructors spend their time bouncing around training missions and don't get much "real world" experience, despite the hours piling up. I don't know if that's the case with yours or not, but remember that few instructors have seen it all. Good on you to ask questions and participate in these discussions, as it will broaden your horizons considerably.

 

[dmccormack]

Multiple tools + multiple views = information you can use to decide where to go. XM weather, eyeballs and stormscope combined are fairly good.

Yep -- the combination gives me confidence to skirt convective activity -- I'd probably stay VFR or on the ground without the combination of data sources.

 

[Ted]

Turn it off, of course.

B)

Let me know how that works out for ya!

Ted, the other thing you need to consider as you do you IR training and then start to use it is that many, many instructors spend their time bouncing around training missions and don't get much "real world" experience, despite the hours piling up. I don't know if that's the case with yours or not, but remember that few instructors have seen it all. Good on you to ask questions and participate in these discussions, as it will broaden your horizons considerably.

Advice appreciated. My instructor hasn't seen everything (but nobody has, at least as far as I'm concerned). He has, however, seen over 5,000 hours worth, very little of which is actually instructional time. He never needs to get a safety pilot to stay current for IFR work because he gets enough actual IFR flying that he always maintains his currency, mostly hard IMC in the Navajo. So, his experience is very real world. What I don't know is how much he uses stormscopes. His Navajo has radar, but I don't remember if it has a stormscope. Either way, he has the radar so I believe he uses that a decent amount. The visual avoidance method is what he listed as preferable. The more I've read on it, it seems most of the people who are alive to tell about flying around thunderstorms use that method, as well, so I like it. But if you've read my other posts, you know I agree with you on more information = more better.

One thing I have noticed is that everyone trusts different things based on their experiences, and you'll almost always get contradictions. After enough flying I'll figure out what I trust myself. For the time being, I don't have enough experience to really come to too many conclusions on my own, so I'll work on continuing to learn for the time being.

 

[dmccormack]

Let me know how that works out for ya!

I turn it off all the time!








(In VMC local, of course!)B)

Actually, yesterday I was flying back from DC area. I was at 8000 and still in the haze layer. I called in a PIREP and let them know that in-flight vis might have been 7. Flight Watch said they had a similar PIREP, but far Southeast.

Usually over the mountains the Haze layer doesn't reach up quite so high -- winds and mixing turn the moisture into scattered CU.

Anyway, I had the Stormscope on (habit) and saw repeated strikes at 200 nm range.

I turned on the 496, and -- sure enough -- Williamsport had a nice line of CB nearby.

Hopefully you weren't testing out your Stormscope skills yesterday at about 1930 local??

 

[gprellwitz]

For the time being, I don't have enough experience to really come to too many conclusions on my own, so I'll work on continuing to learn for the time being.

Hopefully you'll continue to learn for more than the time being!

 

[Ted]

...Anyway, I had the Stormscope on (habit) and saw repeated strikes at 200 nm range.

I turned on the 496, and -- sure enough -- Williamsport had a nice line of CB nearby.

Hopefully you weren't testing out your Stormscope skills yesterday at about 1930 local??

Hmm... at 1930 local I was sitting in my kitchen talking to people on LiveChat, but I certainly don't recall there being WX of that nature around at that time. Then again, I wasn't paying attention.

I was up earlier (about 1700 local) taking one of the interns for his first flight in a small plane. WX then was very nice... not quite clear and a million, but close and wind only about 4 kts. We hit a little bump in the air and he said "Wow, there's a lot of turbulence" and I laughed. It's been a while since I've flown in air that smooth.

Hopefully you'll continue to learn for more than the time being!

Of course, Grant! But for the time being I'll continue learning until I get to a point where I can continue learning, but at least have enough info to come to some initial opinion.

 

[tlglenn]

many, many instructors spend their time bouncing around training missions and don't get much "real world" experience, despite the hours piling up.

I began an IPC once on a day where the winds aloft were 34 knots and the surface winds were gusting to 20+ knots. My CFII and I were at the airplane when two guys (including a CFI) wandered over from a nearby flight school wondering who would try to go flying under those conditions. I mentioned that it was an IPC and a day like that would be good practice for me. The other CFI said that you usually don't encounter windy conditions like this in IMC. After they wandered off my CFII, who has plenty of real world experience, had his own comment to add.

 

[TMetzinger]

Lucky. I was arrlving at ARR one night and Chicago was NOT authorizing deviations for folks that were picking up ice. One tried the "unable" line and was promptly given "immediate turn 180 degrees from present heading, state intentions."

"Roger, 180 degrees, my intentions are to land somewhere safely, and then make plans to beat the **** out of you, over."

 

[KennyFlys]

What is it with Chicago? I've never heard these stories out of other major terminal areas.

 

[dmccormack]

What is it with Chicago? I've never heard these stories out of other major terminal areas.

There's a competition to see which city can replace NY for nastiness...

 

[Ted]

There's a competition to see which city can replace NY for nastiness...

Meanwhile, NY ATC is actually quite friendly, at least to me.

Maybe it's becaus I start my calls to them like this: "Yo wassup NY Approach, dis be Archer 3562G fo shizzle, ova."

 

[dmccormack]

Meanwhile, NY ATC is actually quite friendly, at least to me.

Maybe it's becaus I start my calls to them like this: "Yo wassup NY Approach, dis be Archer 3562G fo shizzle, ova."

NY ATC is da best!B)

Even Manhattan has become -- I dunno -- civil?

When I drive in Manhattan I'm still poised to do battle. Then some cabbie waves me ahead....

Now the LIE....

 

[gprellwitz]

What is it with Chicago? I've never heard these stories out of other major terminal areas.

There's a competition to see which city can replace NY for nastiness...

No, Chicago PEOPLE are good; it's Chicago Approach that's bad. From what I hear, NYC Approach is just fine. Maybe Da Mayer's been spending time with the controllers?