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Thread: Picking the right day (9/07/19) to practice cross-country soaring

  1. #1
    Join Date
    Jan 2011
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    Schleicher ASW-24
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    Picking the right day (9/07/19) to practice cross-country soaring

    Some days the lift seems to be everywhere (almost). Other days, you either ...

    • end up cancelling due to the obvious lack of good soaring, or
    • you don't cancel but go for a sled ride - that is, tow up and glide back to the ground with no climbs after release from the tow plane.


    This posting is about how to plan ahead. Fly on the good days. You need to practice on a regular basis, which for most people is no more than every couple of weeks during the soaring season. If you are not yet cleared for flying cross-country flying in the ASW-24, then you need to practice. This article describes my approach to picking a flying day.

    Monitor the various forecast tools. You should be planning a minimum of five days in advance.


    • Watch changes on windy.com. https://www.windy.com/39.155/-122.14...sure,m:eKqacLA Schedule your family time/ social life and schedule your glider - that is, narrow down your schedule as to what day(s) you will plan to fly.
    • 5 days ahead of the planned flight - start looking at the 7 day NorCal RASP. https://rasp.nfshost.com/norcal-coast/
    • when you see a potentially good day coming, schedule your glider.
    • 3 days ahead - pay close attention to the Williams RASP http://www.huckbone.com/wscrasp.html - but monitor windy.com to try to understand the forces at work.
    • 24 hours prior (in this case - Friday morning after 8 AM) keep monitoring the RASP - know where the lift will be, how high, how strong.
    • the night before (in this case Friday night after 8 PM) - review the next to last fcst (RASP) that you will have, and review your plans- revise as needed.


    I picked Saturday 9/8/19 as my day to fly. I arranged my social/ family activities so I had that day free and then I scheduled the glider with Cora/ Noelle three or four days in advance.

    The night before (Friday night), it looked like it was going to be good day to ...

    • tow to Tree Farm,
    • run north on the Mendos,
    • turn around somewhere up north at 10,000 ft and
    • come home and land after a nice 3 or 4 hour flight.


    It's good to have a plan, but, as usual the forecast changed.

    Windy.com revealed strong winds overhead, doing nearly a 180 degree turn from south to north over the bay area (see the next post below for that graphic).

    The RASP on "the morning of" (Saturday after 8 AM) told me otherwise, also, looking out the window, even told me it was probably a poor flying day.

    The soundings for 11 and 12 noon predicted high clouds at 26,000 and above (see the black line on the top left...
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    The sat photo displayed the high cirrus in motion (along with coastal low clouds)... the link is on the vsa weather page... https://www.valleysoaring.net/weather/

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    At first, my inclination was to cancel the flight altogether, but I did have the day free, so maybe I could log a couple of hours - just not go anywhere...

    The new plan...

    • tow to Tree Farm after 2 PM when the Cirrus was gone,
    • maybe go north on the Mendos... (if, and only IF, we could get above 8,000 at Sheet Iron (not likely based on teh fcst)), otherwise,
    • enjoy the lift in and around Goat, Snow and St John - and
    • log a couple of hours


    ... and we did just that.

    Click image for larger version. 

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ID:	5375 Thomas Duncan doing the driving as I snapped the photos...

    The last of the cirrus, that I had observed on both Windy.com and the sat photo, is a clearly visible line... you can imagine the 100 MPH winds in the middle of it moving south to north...

    Click image for larger version. 

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    The cumulus clouds were perfectly positioned over Goat, Snow and St John.

    Rather than circle at the top of each thermal, we practiced searching for new thermals.

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ID:	5367 The one thing you DO NOT WANT TO DO is practice bad habits. When you get to apparent top of a thermal head out. Do not stay and circle when you are not going up! If you do, you are practicing bad habits. In fact, if the lift decreases by half and you have a comfortable altitude to get to the next thermal that you have in mind, then GO! Staying too long in thermals is a hard habit to break.

    After 90 minutes or so of running around the Goat- Snow- St John- and Sheet Iron area, we headed for the valley and searched for, and explored the line of lift that was on the RASP fcst that morning. The lines were shown on the BL Max up down and the 850 MB charts. We found that line of lift! ... and had fun in that too.

    Click image for larger version. 

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    We found that convergence line...

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    Then as we headed for home and needed to lose the extra 4,000 ft of altitude we now had, we practiced some precision flying maneuvers prior to entering the landing pattern.

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    If you are serious about wanting to fly gliders cross-country, then the one thing you should do for sure is buy "See You" and analyze each and every flight. It costs about the same as one tow and it is money well invested - if you want to learn to fly cross-country. See: https://www.naviter.com/products/seeyou/

    after each flight, compare your flight track to the plan you had and to the RASP forecast maps.

    Look closely at your thermaling style... are you making round circles (constant airspeed) and drifting with the wind?, are you centering in the thermals?, are you in sink before you leave the thermal? are you flying slowly while in sink between thermals? etc.

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    Go back and look at the forecast RASP charts for that day. Compare your flight to the forecast. You will undoubtedly discover that the RASP was providing you all of the info you needed.
    See the VSA weather page to see how to see yesterday's RASP.



    Post you questions and let's have conversations about this flight or about practicing x-c in general.

    Ben had asked me to assemble a list of the posting here on Williams Today that might help newer pilots read the RASP..
    . and. Reading the wx forecasts. ... in general.. I will add this post to the list of Training pages -https://www.valleysoaring.net/training/
    Last edited by Peter Kelly; 09-10-2019 at 06:08 AM.
    Peter Kelly

  2. #2
    Join Date
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    Schleicher ASW-24
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    Re: Picking the right day (9/07/19) to practice cross-country soaring

    Couple more graphics for this flight on 9/07/19

    I didn't save the windy.com images from the night before or from the morning, but this one is from 11 PM Saturday night - some 7 or 8 hours after I had landed.

    Click image for larger version. 

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    This is the wind at 34,000 ft. The wind reflects the pressure lines. Some 14 hours earlier, those winds were flowing strongly at about 100 kts, coming down the coast from the NW and making a sharp 180 to the north - that is a tight trof of low pressure and it was directly overhead on Saturday morning as was all of the high cirrus.

    With practice you will learn to use windy.com effectively.

    The RASP has a lot of other pages I reviewed, but did not address on my initial entry above.

    Nice Cu Clouds were forecasted - as shown on the 1500 hour fcst....

    Click image for larger version. 

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    Last edited by Peter Kelly; 09-09-2019 at 12:13 AM.
    Peter Kelly

  3. #3
    Join Date
    Nov 2012
    Location
    Rio Vista, CA
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    69

    Re: Picking the right day (9/8/19) to practice cross-country soaring

    Great informative posting. Thank you.

    Tom Jue

  4. #4
    Join Date
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    Location
    Woodland
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    Re: Picking the right day (9/07/19) to practice cross-country soaring

    Peter,
    I appreciate the time and effort you put into an analysis of your flights like the one we had on Saturday. Thank you for another great training day, both in the air and on the ground. Thanks, too, for you patience as I demonstrated some of those “bad” habits. I would add the importance of regular scheduled training. For a variety of reasons I wait too long between flights and it is often like starting all over.
    Thomas Duncan

  5. #5
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    Re: Picking the right day (9/8/19) to practice cross-country soaring

    Quote Originally Posted by Thomasj View Post
    Great informative posting. Thank you.

    Tom Jue
    Thanks Tom. Like you - just trying to make a contribution to the soaring community.
    Peter Kelly

  6. #6
    Join Date
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    Re: Picking the right day (9/07/19) to practice cross-country soaring

    Re: Thomas D... We did fine. I think our flight was a good example of good flying, no "bad" habits demoed on our flight.
    Last edited by Peter Kelly; 09-10-2019 at 10:20 AM.
    Peter Kelly

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