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Alexb2000

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Alexb2000
When people think about or debate XM weather the topic is always around trusting the composite radar image or not, this thread is NOT about that.

I believe XM weather is an awesome tool that has done more to save me time, money, and upset passengers than almost anything else on my bird. One of my favorites is the winds aloft function. Using it to build a mental image of the winds along a 600 mile flight is great. Do I climb or stay low, when do I climb and to what altitude, what will the ride be like, etc.

So I'll kick it off with an example using the above XM winds.

I put 8 hours on the Hobbs today Dallas-Taos-Dallas. Going I was bucking some pretty strong headwinds. I step climbed my way out to NM timing the climbs according to when the winds were the most favorable. That meant I was able to save a fuel stop on a day when climbing to altitude x and flying would have guaranteed one.

Coming back we were getting hammered by turbulence at 11K. I was looking at the winds aloft and noticed a really strong steam of southbound wind blowing between the TX NM border and about Wichita Falls. As I entered that area it was still really rough. Then looking at the winds I realized I was in a boundary area for that wind stream. So I climbed to 13K to get into the middle of it, instant smooth air although the winds were really blowing at 75 Knots. I didn't care, it was almost neutral to my flight path and most important the strong winds flattened any turbulence. Result, nice ride home when almost everyone on frequency was bitching about light to mod.

So who else uses XM and how?
 

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I saw your flight path and was noticing the ugly headwinds you had heading out. That was definitely a good use of XM.

I let my XM subscription lapse. When I had it, I used it to help vector myself around bad areas way far out from the action. Now I'm waiting for ADS-B to get to the point where it's worth getting for me - which is basically when it covers the whole country.
 
I, too, love the XM weather on my 496. I have a more basic package, though, so I do not get winds aloft. I use it 90% of the time for the NEXRAD images, and the rest for METARS.

Wells
 
It has been good, but I'll be switching to ADS-B soon, to save the $53/mo.
 
scottd said:
Most likely changing altitudes to get into smooth air at 13K had nothing to do with the wind.
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I hate talking about weather, because I quickly get out of my depth.

Anyway, I have noticed that strong winds aloft with low surface winds usually mean smooth air. My logic was the strength of the winds aloft more or less flattened the turbulence. It's been consistent enough that I look for those wind conditions.

Once you get done laughing, why does that occur?
 
Then maybe that upper level disturbance and weak cold front that moved through. Help us Scott.
 
scottd said:
Looks like you need a bit more education in weather.



Actually, that can be quite the opposite. What you generally want to look for is strong winds at the surface and lighter or similar winds aloft. I developed this member workshop that discusses the role of wind and turbulence.
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Scott-

No offense, but I'm just a guy flying a plane and observing the weather, which is certainly non-scientific but that doesn't make what I observed untrue. There was no storm system yesterday, surface winds were light, turbulence both low and high was LGT-MOD as reported by many airliners. Barometer was fairly consistent (around 30.20 if I remember correctly) across the entire trip.

I observe this pattern many times a year. Two weeks ago I crossed the Palo Flechado Pass with winds in excess of 50 knots surface winds calm, only a couple of ripples.

Why else would I fly in 75 knot winds?
 
Alexb2000 said:
Why else would I fly in 75 knot winds?
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Because you're getting one awesome tailwind, it doesn't matter too much...

Plenty of reasons. :)
 
scottd said:
Don't know that answer. But I wouldn't use your "observations" as a way to predict what might happen on other flights with a similar wind pattern. Sort of like dividing 19/95 and getting 1/5th by crossing out the 5s. May work in this instance, but there's more to turbulence than just wind. A little education will go a long way.
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So then what would you attribute Alex's smooth winds to?
 
Ted DuPuis said:
Because you're getting one awesome tailwind, it doesn't matter too much...

Plenty of reasons. :)
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I wish. I almost turned SSW to Houston just to see some speed for a change. I'm sure not the fastest bird in the air.:wink2:
 
Alexb2000 said:
I wish. I almost turned SSW to Houston just to see some speed for a change. I'm sure not the fastest bird in the air.:wink2:
Click to expand...

A T310R is calling your name. ;)
 
I do the same thing you do when it gets bumpy. No reason not to be pragmatic unless Sigments Airmets or Pirs indicate otherwise. I had over 70 knots off the nose returning from Dallas. When it got bumpy at 10,000, 12,000 provided smooth air even though a bit slower ground speed. Passengers didn't mind the trip being a bit slower, bit did mind constant bumps. Sometimes it's bumpier higher. On this trip, bumpy higher and lower, but 12,000 was great.

Dave
 
Alexb2000 said:
I was thinking about that, but an RV-10 was recommended as the ultimate high speed load carrying piston.:dunno:
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I hear that recommendation is lacking some substance.
 
You haven't been paying attention. Turbulence doesn't affect RV's.
Alexb2000 said:
I was thinking about that, but an RV-10 was recommended as the ultimate high speed load carrying piston.:dunno:
Click to expand...
 
Dave Siciliano said:
I do the same thing you do when it gets bumpy. No reason not to be pragmatic unless Sigments Airmets or Pirs indicate otherwise. I had over 70 knots off the nose returning from Dallas. When it got bumpy at 10,000, 12,000 provided smooth air even though a bit slower ground speed. Passengers didn't mind the trip being a bit slower, bit did mind constant bumps. Sometimes it's bumpier higher. On this trip, bumpy higher and lower, but 12,000 was great.

Dave
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Dave-

Does XM offer you any value in your bird?
 
Alexb2000 said:
Dave-

Does XM offer you any value in your bird?
Click to expand...

Not Dave, but the Cheyenne had XM in it. Aside from seeing the winds (which tend to get high up there, and can have some interesting changes with altitude), it was also nice to see the weather at your destination, which was often 200-300 nm away and one hour.
 
http://weather.unisys.com/upper_air/skew/ua_sound.php?type=no&city=kama&region=sp&t=-12

Looking at this Skew-T for Amarillo...

My guess would indicate a stable atmoshere at 12-15,000' due to a decreased lapse rate and a dry lower atmosphere.

At this time the dewpoint decreased and gusts began which appears to be the weak cold front moving in.

Conditions at: KAMA (AMARILLO , TX, US) observed 1753*UTC*01 March 2013
Temperature: 8.3°C (47°F)
Dewpoint: -6.7°C (20°F) [RH*=*34%]
Pressure (altimeter): 30.30*inches*Hg (1026.2*mb)
[Sea-level pressure:*1026.1*mb]
Winds: from the NNW (330*degrees) at 20*MPH (17*knots; 8.8*m/s)
gusting to 26*MPH (23*knots; 12.0*m/s)
Visibility: 10 or more miles (16+ km)
Ceiling: at least 12,000 feet AGL
Clouds: sky clear below 12,000 feet AGL
Weather: no significant weather observed at this time
 
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Alexb2000 said:
Dave-

Does XM offer you any value in your bird?
Click to expand...

Absolutely! I very much rely on it for the RADAR from a strategic perspective. METARS at arrival airport. AIRMET AND SIGMET updates while in the air. Winds aloft mainly for rate and changes in direction. I subscribe to the Aviator package. Wonderful for big picture stuff. On- board RADAR for close in, real time information. Storm scope still shows storm intensity. I really use all the tools. Many times, I watch a system while enroute to see how it develops. It may affect altitude I fly at, fuel planning, may help if turbulence is reported. As far as storms: intensity, how fast it's moving, direction can all be helpful and I can check alternates in the air. If it's a solid, rapidly moving intense line, I'm probably not fooling with it. More open with holes, slower moving with lower tops, I can probably pick my way around, over or through. Many times, one can't exactly tell what's going to happen until it actually develops. For instance, systems commonly move in from the NE here and meet warm moist Gulf air. Weather folks may show the coming low and look at signs for how strong the system my be, but can't tell exactly how it will form. The last one went north of Dallas, although, it was projected to dump a lot of rain on it. So, in the air, I watch it actually develop and it may be something I can deal with. If not, I've pulled up or diverted more than once.

Last week, flying to Charlotte, I went in behind a system (large low). Ceilings weren't predicted to be as low as they were, but we noted temp and dew point proximity in METARS and were prepared for low ceilings and fog, which turned out to be there after hanging around much longer than predicted when I left. Flew over an excellent alternate behind the system on the way in. Nice to verify weather there before proceeding into worse weather. Many other uses, but these are most common. Pireps are also very helpful at times. I can see things graphically rather than have Fliight Watch try to explain them. See them actually moving and developing and go right to information that is most helpful to me. TFRs on there are also critical in today's environment, even when going IFR. Saw one pop up at a destination while I was in the air. Nice to know ahead, rather than have approach inform me close in and deny a clearance. Flew over one that popped up on another flight. I'm sure center would have diverted me when I got to it, but I was able to plan ahead and deal with it much better.

Best,

Dave
 
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