Decision Making for XC and wave soaring from Byron Ramy Yanetz February 2010.

Decision Making for Decision Making for XC and wave XC and wave

soaring from Byronsoaring from Byron

Ramy YanetzRamy YanetzFebruary 2010February 2010

Byron Soaring PotentialByron Soaring Potential Great and consistent soaring conditions are only 20 miles away Great and consistent soaring conditions are only 20 miles away

from March till Octoberfrom March till October Strong convergence often marked with clouds over the San Antonio Strong convergence often marked with clouds over the San Antonio

Valley in the Diablo Range (between Rel 1, Red Mountain and Mt Valley in the Diablo Range (between Rel 1, Red Mountain and Mt Stake) , persists all day with typical altitude of 6000-8000, Stake) , persists all day with typical altitude of 6000-8000, occasional 10,000 feet (highest 13,500!).occasional 10,000 feet (highest 13,500!).

Easy glide back to Byron or Tracy.Easy glide back to Byron or Tracy. May require 20-25 miles 6000-7000ft tow to Rel 1,2,3 when local lift May require 20-25 miles 6000-7000ft tow to Rel 1,2,3 when local lift

not presents.not presents. 25 miles tow @ 70 knots = 30 minutes tow plane round trip ($82).25 miles tow @ 70 knots = 30 minutes tow plane round trip ($82). Equivalent in cost and time to 2 typical towsEquivalent in cost and time to 2 typical tows 10/14 saw 6 high tows to the Diablo range in a period of 3 hours 10/14 saw 6 high tows to the Diablo range in a period of 3 hours

resulting in record distance and altitude (13,000 feet)!resulting in record distance and altitude (13,000 feet)!

Where to Release?Where to Release? Make sure to use the Hollister database to find the release areaMake sure to use the Hollister database to find the release area Tow towards release 1 (Rel 1) at 70-75 knots so you will arrive there Tow towards release 1 (Rel 1) at 70-75 knots so you will arrive there

between 6-7000 feet in about 15 min.between 6-7000 feet in about 15 min. Release (or stay on tow) and proceeed towards Rel 2 along the spine until Release (or stay on tow) and proceeed towards Rel 2 along the spine until

you find your first lift.you find your first lift. No need to stay on tow beyond Rel 2 or above 7000 feet which is sufficient No need to stay on tow beyond Rel 2 or above 7000 feet which is sufficient

altitude to search for lift without loosing glide to Byronaltitude to search for lift without loosing glide to Byron First lift is usually near Rel 2First lift is usually near Rel 2 If not proceed to Rel 3 and/or to Red Mountain on the edge of the San If not proceed to Rel 3 and/or to Red Mountain on the edge of the San

Antonio valleyAntonio valley The lift is almost always in the area between Rel2,3, and Red Mountain.The lift is almost always in the area between Rel2,3, and Red Mountain. Follow the convergence line between red mountain and Mt StakeFollow the convergence line between red mountain and Mt Stake If no lift found head back to Byron before loosing glide (or Tracy if Byron is If no lift found head back to Byron before loosing glide (or Tracy if Byron is

not in glide).not in glide). Easy in a 40:1 ship but also doable in a GrobEasy in a 40:1 ship but also doable in a Grob

Release AreaRelease Area

Landout optionsLandout options Meadowlark (good strip, friendly owner, easy Meadowlark (good strip, friendly owner, easy

ground retrieve)ground retrieve) San Antonio Valley (in the Diablo Range) - San Antonio Valley (in the Diablo Range) -

Landing strip and good fields – 1 hour drive Landing strip and good fields – 1 hour drive from Byron (locked gate but key is available)from Byron (locked gate but key is available)

Tracy – Quick aeroretrieve (< $50)Tracy – Quick aeroretrieve (< $50) New JerusalemNew Jerusalem Patterson Patterson Crows Landing (Huge, but access unknown)Crows Landing (Huge, but access unknown) GustineGustine Los BanosLos Banos

How to use blipmaps to How to use blipmaps to determine when to tow to the determine when to tow to the

Diablo RangeDiablo Range

NAM BLTop > 6000 ftNAM BLTop > 6000 ft NAM Cu potential >= 0 and Cu Base > 6000 ftNAM Cu potential >= 0 and Cu Base > 6000 ft RASP Hcrit > 6000 ftRASP Hcrit > 6000 ft However If NAM predicts good cu’s (cu potential > 0) However If NAM predicts good cu’s (cu potential > 0)

and cloud base of at least 4000ft all the way north across and cloud base of at least 4000ft all the way north across the delta then plan to fly north towards Rio Vista and the delta then plan to fly north towards Rio Vista and WilliamsWilliams

Detrermine best time to launch. Typically no later than Detrermine best time to launch. Typically no later than noon, and as early as 10AM if the 10AM RASP indicates noon, and as early as 10AM if the 10AM RASP indicates good lift.good lift.

Byron WaveByron Wave

Byron wave season Nov-AprilByron wave season Nov-April Pre frontal wave is best during the hours before Pre frontal wave is best during the hours before

the onset of rain with increasing SW winds. the onset of rain with increasing SW winds. Pre Frontal Wave can be found anywhere Pre Frontal Wave can be found anywhere

between Byron and Los Vaqueros reservoirbetween Byron and Los Vaqueros reservoir Often marked with Lenticular clouds or foehn Often marked with Lenticular clouds or foehn

gapsgaps Pre frontal wave can be over wide area between Pre frontal wave can be over wide area between

Mt Diablo to Mt Oso along the mountain rangeMt Diablo to Mt Oso along the mountain range

Diablo North wind WaveDiablo North wind Wave Usually during high pressure off shore events from Nov – AprilUsually during high pressure off shore events from Nov – April Requires NNW-NNE winds above 20 knots at Mt DiabloRequires NNW-NNE winds above 20 knots at Mt Diablo Usually not marked by clouds other than some high cloudsUsually not marked by clouds other than some high clouds Wave is typically weak (1-2 knots) and very small area (less than 1 Wave is typically weak (1-2 knots) and very small area (less than 1

square mile) between Wave1 and Class Bravosquare mile) between Wave1 and Class Bravo Due to significant sink surrounding the wave it is crucial to tow all Due to significant sink surrounding the wave it is crucial to tow all

the way to the wave. Avoid the temptation to release early!the way to the wave. Avoid the temptation to release early! Stay in the area and move over class bravo if necessary when Stay in the area and move over class bravo if necessary when

above 10K.above 10K. Typical altitude 12-18KTypical altitude 12-18K

Wave 1Wave 1

How to use blipmap to recognize How to use blipmap to recognize good wave daygood wave day

Ignore all the thermal related parameters (BLTop, Hcrit, Cu Pot, BL Ignore all the thermal related parameters (BLTop, Hcrit, Cu Pot, BL Up/Down, Convergence)Up/Down, Convergence)

Focus on winds aloft (Wind Speed and direction at boundary layer) Focus on winds aloft (Wind Speed and direction at boundary layer) and wave parameters.and wave parameters.

NAM is available up to 3 days in advance but only indicates wind. NAM is available up to 3 days in advance but only indicates wind. Look for wind above 15 knots from the North or SW. Look for wind above 15 knots from the North or SW.

RASP wave parameters, especially the 750m model (available late RASP wave parameters, especially the 750m model (available late in the prior evening) are the best indicators. in the prior evening) are the best indicators.

Check the vertical velocity at 850, 700 and 500 mb as well as the Mt Check the vertical velocity at 850, 700 and 500 mb as well as the Mt Diablo Cross section. Should be over 100 cm/s (2 knots) for a Diablo Cross section. Should be over 100 cm/s (2 knots) for a usable wave.usable wave.

On the day itself check the wind on top of Mt Diablo online or by On the day itself check the wind on top of Mt Diablo online or by phone. Look for average wind speed above 20 knots from the SW or phone. Look for average wind speed above 20 knots from the SW or from the north.from the north.

ResourcesResources

Go to NCSA web site Go to NCSA web site http://norcalsoaring.org/http://norcalsoaring.org/ and study the cross and study the cross country and weather sections, as well as the RASP linkscountry and weather sections, as well as the RASP links

Download latest waypoints for Byron/Hollister area Download latest waypoints for Byron/Hollister area http://soaringweb.org/TP/Hollisterhttp://soaringweb.org/TP/Hollister

Mt Diablo wind (925)838-9225Mt Diablo wind (925)838-9225 http://raws.wrh.noaa.gov/cgi-bin/roman/meso_base.cgi?stnhttp://raws.wrh.noaa.gov/cgi-bin/roman/meso_base.cgi?stn=MDAC1&unit=0&time=LOCAL=MDAC1&unit=0&time=LOCAL

Study routes using google map Study routes using google map http://maps.google.com/maps?q=http://soaringweb.org/TP/Hollister/http://maps.google.com/maps?q=http://soaringweb.org/TP/Hollister/hllstr0b.kmz&z=7hllstr0b.kmz&z=7

Study landouts data Study landouts data http://www.soaringnet.com/landout_data/hollisterhttp://www.soaringnet.com/landout_data/hollister

Download IGC files from OLC and study with SeeYouDownload IGC files from OLC and study with SeeYou