Williams Soaring Wave Window

FILES for Download

WSC Wave (SUA) File

Effective 02-22-2016

OpenAir SUA File Format:



Wave Window, waypoints, and areas of expected lift.



Sectional Map, Wave Window and waypoints.






Wave Map Description

The SeeYou Wave & Waypoints map has been marked with expected Wave Lift areas.

The blue line boxes on the map illustrate the boundaries of the Williams Glider Area North and South, aka "Wave Windows".

The locations that you can expect to locate the wave lift have been marked with colored lines.

Wave forms slightly downwind of the peaks of the ridges.  Although the ridges below our wave window vary in height, length and geographic orientation, we tend to have the most consistent and predictable wave with a generally west flow, with areas of the primary wave illustrated in pink. However, with the variations in terrain and daily changes to the atmospheric stability, you may find secondary waves repeating all the way to the center of the Sacramento Valley.


















In 2015 Pat Alford took the initiative and coordinated and completed a major revision to the WSC Wave Window, working with Oakland Air Traffic Control Center. Pat enlisted the assistance of Kempton Izuno, Pete Alexander, Peter Kelly and Jim Darke,and their efforts are reflected here. As usual for many of the WSC Web pages, Peter Kelly provided significant assistance in the production of this page.


Wave Window Procedures & Pilot Safety

Letter Of Agreement between FAA Oakland ARTCC and WSC is Effective Feb. 22, 2016

Wave flying is just one more of the many benefits to pilots who choose to fly from Williams Soaring Center. Although there are many days when the nearby lift will go to well over 25,000 feet, pilots are not authorized to fly above 18,000 feet without clearance. We have a specific agreement with the FAA that allows such high altitude flights once clearance is received. This page provides the details of that agreement.

Pilots must read and understand the current agreement.


The Wave Window is NOT always open!

  1. Oakland ARTCC only opens the wave window on request from WSC Management via telephone.
  2. It is NOT opened via a radio call to Oakland ARTCC.
  3. You MUST coordinate with the office at WSC.


Flying The Wave

The best wave days are when the wind is at right angle to the ridge lines with diminishing reliability up to as much as 45 degrees off set from true right angles. However, the ridge lines below our wave window are not continuous, since there are gaps in the ridge, and to complicate it further, the alignment of the ridge lines varies on both the sides of the ridge, that is, both the windward side and the downwind side.


When considering alignment, give more consideration to the downwind side of the ridge rather than the windward side. For example, the western perimeter of Glider Area North, is aligned with a course from Goat TP to Anthony TP and that is a true course of about 340 degrees.

However, the downwind face of that terrain is more aligned with a line from the Goat TP to the M-6 TP which is a true course of about 005 degrees. Thus with the wind coming from anywhere between south west and northwest, you will find the best lift on a line of about due north from Goat. Thus, the heart of the wave window is directly over the most probable area you will find wave lift. That said, you may also find a good line of wave lift on a 340 course directly to the Anthony TP, about parallel to the western perimeter of Wave Area North, but that lift will be a result of the large ridge north of the Gravelly TP. Keep in mind that the wave patterns aloft will replicate the ground contours below that wave. (See map "SeeYou Wave & Waypoints")


The reported direction of the wind aloft, whether it is on a forecast or it is displayed on your ClearNav is always displayed in Degrees True, not in Degrees Magnetic. This is significant in our area since the variation in our area is over 14 degrees. This fact comes into play mostly when you are planning your flight and evaluating the direction of the wind.


Williams Glider Area North and South, the "Wave Window"

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Oakland Air Route Traffic Control Center and Williams Soaring Center


(Original LOA on file at Williams Soaring Center)

EFFECTIVE :  February 22, 2016

SUBJECT:   Glider Operations

  1. PURPOSE: To establish areas and procedures for glider operations within Class A Airspace under the jurisdiction of Oakland Air Route Traffic Control Center (Oakland Center).
  2. CANCELLATION: This agreement cancels the Oakland Center and Williams Soaring Center, Letter of Agreement , Subject: Glider Operations, dated December  1, 1995.
  3. AUTHORIZATION: This agreement authorizes the Williams Soaring Center (WSC) to deviate from the requirements of FAR 91.135 b and c, when operating in the areas specified in the Attachment.
  4. SCOPE: The procedures outlined herein apply to flights conducted at FL 180 and above within the Williams Glider Areas as depicted in the Attachment.
    1. Pilots Must:
      1. Comply with all applicable Federal Aviation Regulations, except for deviations specified in this Letter of Agreement.
      2. Operate in the glider areas at or above FL 180 only during time periods approved by Oakland Center and 1 Reconnaissance Squadron (1 RS), Beale AFB.
      3. Familiarize themselves with local terrain features, so that flight will be contained within the glider areas by visual reference to the ground.
      4. Not operate in the glider areas when flight visibility is less than 5 miles or when visual reference to the ground cannot be maintained at all times.
      5. Maintain 1,000 feet vertically and 1-mile horizontally from any cloud formation.
      6. If the aircraft is transponder equipped squawk 1202 and enable Mode C.
    2. Oakland Center:
      1. Must keep all aircraft under their jurisdiction vertically or laterally outside the confines until the glider area is released back to Oakland Center.
      2. Is not responsible for separation between gliders operating within the glider areas.
    1. WSC Must:
      1. Request from Oakland Center North Area Operations Supervisor/Controller In Charge (CIC), at 510-745-3440 , a block of altitudes at or above FL 180 and give the following information:
        1. Call sign.
        2. Requested  designated  glider area.
        3. Time period .
        4. A contact number for the WSC in the event the operation must be amended or terminated.
      2. Release reserved airspace back to the Oakland Center Supervisor/(CIC) by telephone if for any reason glider operations are suspended prior to the coordinated time .
      3. Coordinate the use of Williams Glider Areas with 1 Reconnaissance Squadron (1RS), Beale, AFB at 530-634-8818 a minimum of 1 day in advance for all days of intended use with  the  exception of weekends or federal holidays. Oakland Center Supervisor/CIC is not responsible for coordination with 1RS.
    2. Oakland Center Must:
      1. Suggest alternate time periods or altitudes if the request time or altitude is not available .
      2. Specify which area, time period , and altitudes, and must be coordinated on a daily basis.
  7. ATTACHMENT: Williams Glider Areas (Maps, Coordinates)

Melissa Holmes
Air Traffic Manager Oakland  ARTCC

Pat Alford
Coordinator, Williams  Soaring Center

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Wave Window - PROCEDURES

  1. Planning:
    1. Pilots planning to use the Wave Window, other than weekends and federal holidays, should contact WSC a minimum of one day in advance of intended use to allow coordination as required by the Letter of Agreement.
  2. Opening The Wave Window:
    1. WSC will coordinate the use of Williams Glider Areas with 1 Reconnaissance Squadron (1RS), Beale, AFB a minimum of 1 day in advance for all days of intended use with the exception of weekends or federal holidays.
    2. When it appears to the pilot that they may be able to gain enough altitude to use the wave window, they will contact WSC via radio and request that the Wave Window be opened.
    3. WSC will advise the pilots of the operating times of the window and the maximum altitude authorized by Oakland ATCC. Pilots may NOT enter the wave window without permission from WSC.
    4.  Pilots may NOT open or close the wave window with Oakland ATCC via radio.
  3. Pilot Procedures:
    1. Pilots must understand and comply with the Letter of Agreement.
    2. A maximum altitude will always be specified. Pilot must acknowledge the maximum authorized, and must not exceed that altitude.
    3. Reset and use an altimeter setting of 29.92 while in the wave window.
    4. Advise WSC when entering the wave window.
    5. Advise WSC when no longer in the wave window.
    6. While in the wave window, pilots must remain within the lateral boundaries and stay in radio contact with WSC. Pilots must have an operational moving map navigation system, and use it. It is virtually impossible to remain within the boundaries without a moving map.
  4. Techniques on Wave Flights:
    1. For best results, release from tow in lift.
    2. Climb as high as you can in the lift you are in before hunting elsewhere, because of the wind, searching for lift is very costly in altitude.
    3. When in doubt high up, go upwind. When in doubt low, go downwind. If you are in the middle, pick one or the other!
  5. High altitude wave flight can be dangerous and pilots should be familiar with wave flight dangers . Pilots are encouraged to prepare for wave flights through proper physiological training and a ride in the Altitude chamber. See Hazards / Caution for some limited information in next section.

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  1. Oxygen use
    1. Be knowledgeable on the physiology of flying at altitudes that require supplemental oxygen. Many experienced pilots do not exceed 18,000 ft. unless they have a pressure system, or a diluter demand system.
    2. Pilots should never fly above 28,000 without having oxygen delivered under pressure. It's basic physics and physiology. As the atmosphere becomes thinner your blood will not absorb the oxygen.
    3. Hypoxia, Time of useful consciousness (TUC) if your oxygen system fails..
      1. A routine exercise in the USAF altitude chamber (conducted every three years for active pilots) was to climb to 30,000 feet, do a rapid decompression, level off at 22,000 feet and remove the oxygen masks. Pilots were then instructed to demonstrate ability to write simple notes or do demonstrate simple mental exercises. The majority of pilots were unable to function after only 4 or 5 minutes without oxygen at 22,000 feet.
      2. If you have a failure of your oxygen system in a glider, and you first recognize such a failure via by your symptoms of hypoxia, you will have only a few minutes to establish a descent to get out of the lift and descend to a safe altitude. You might be able to achieve 1,000 feet per minute, and thus it would require 4 minutes to get down to 18,000 feet from 22,000 ft.
      3. Very few glider pilots carry a backup oxygen system.
  2. Extreme temperatures
    1. Hypothermia is a real problem in a single seat glider. As your core body temperature drops, your ability to make thoughtful decisions is impaired significantly. Blood pressure is lower at higher altitudes. Cold extremities prevent ability to fly normally.
    2. Battery charge will last a shorter time after being exposed to cold temperatures.
    3. Flight controls, including spoilers, are apt to freeze in certain gliders.
    4. Loss of pitot static pressure. The loss of airspeed indication due to a frozen pitot static system is a real possibility. The hazards of not having an airspeed indication is apparent.
  3. Loss of visual references
    1. It is not unusual for heavy frost to form on the inside of the canopy, resulting in nearly total loss of outside visibility.
    2. Envelopment in clouds.
      1. Loss of reference to the ground due to cloud and involuntary entry to IMC because of rapid envelopment in lenticular cloud.
      2. There have been numerous accounts of gliders coming apart due to loss of control (over speed and high g forces) after a wave cloud enveloped the glider. Few pilots carry and use artificial horizons and even those that do are usually not proficient in using them.
  4. Increase of True Airspeed
    1. Maximum allowable indicated airspeed (VNE, as read on the IAS) decreases significantly with altitude. Exceeding aerodynamic limits and the flutter of control surfaces and are real possibilities if VNE is exceeded. VNE refers to indicated airspeed (IAS), whereas aerodynamic loads depend on TRUE airspeed.
    2. The pilot should have a table of VNE in hand or taped to the panel that adjusts the VNE for altitude when flying in wave at higher altitudes.
  5. Extreme Winds
    1. Difficulties caused by extreme wind; structural failure due to high altitude VNE and flutter.
    2. It is not unusual for winds aloft to be nearly the same as your allowable true airspeed. If you are safely respecting the maximum allowable indicated airspeed your ground speed my well be a negative number. The end result of that you may be backing into the wave cloud behind you.
    3. Rotors and extreme turbulence may be found at various altitudes on wave days.
  6. Altimeter accuracy
    1. Above 18,000 feet, pilots should set 29.92 in the Kollsman window of the altimeter and add or subtract the altimeter correction for their instrument.
    3. Do not fly near the upper limit of the authorized airspace if you do not have your altimeter set correctly.


Williams Glider Area North and South - MAP DOWNLOAD

You can use SeeYou Desktop, load the “Wave SUA file” and print your own maps.

We have provided 2 maps for download.

  • WSC-wave-lift-2016.jpg - 234 KB - SeeYou Wave & Waypoints Map: SeeYou Vector Map showing Glider Wave Windows, 2014 waypoint names, and Areas of expected Wave Lift.
  • WSC-wave-sectional-2016.jpg- 916 KB - Sectional & Waypoints Map: SeeYou raster sectional map showing Glider Wave Windows and 2014 waypoint names.


Special Use Airspace (SUA) - FILE DOWNLOAD

WSC-wave2016.txt (1KB) Effective Feb. 22, 2016 per the WSC FAA LOA.



WSC_wave2016.txt file is an “OpenAir" file version that is compatible with most systems. Contents listed on right:


Download the WSC wave 2016 SUA file (OpenAir version) listed above, this file will be referred to the “Wave SUA file” in this documentation.

This file works in:

  • SeeYou desktop
  • SeeYou Mobile
  • XCSoar
  • ClearNav

It should work in WinPilot and GlideNav, but has not been tested.


Downloading on a Windows PC:

  • For Windows Internet Explorer and Microsoft Edge browsers right click the “Wave SUA file” name and select "Save target as", then select the location where you want to save the file and click on SAVE.
  • For Google Chrome and Mozilla Firefox right click the “Wave SUA file” name and select "Save Link As", then select the location where you want to save the file and click on SAVE.




ClearNav supports the OpenAir (.txt) airspace files.

To install the “Wave SUA file” airspace file on your ClearNav, first download the file to your PC. Insert the ClearNav USB thumb drive into a USB port of your PC and copy the file to the Map Data / SUAs folder.

With the ClearNav turned off, insert the USB drive into the ClearNav USB port and turn on the ClearNav. Answer YES to the question "Update Files", select maps.

When ClearNav has loaded, use the Remote Control device and go to Menu> Setup Menu> Special Use Airspace. Select LOAD, and scroll to and select the file.. The file will be loaded. Click Menu to return to the main map screen and you can view the newly installed Wave windows.



SeeYou Mobile version 6.61+ supports multiple airspace files in the SeeYou .cub and OpenAir, .txt file.

The “Wave SUA file” needs to be copied to the “airspace” folder on the SD card of the OUDIE, or to the “Airfields and Airspace” folder in the main program section.

This can be done by connecting your OUDIE to a PC using a USB cable. You could also just remove the SD card from the SeeYou Mobile or Oudie, insert it into an SD card reader on your PC and copy the “Wave SUA file” to the correct folder.

NOTE - YOU NEED TO MAKE THE AIRSPACE ACTIVE from the airspace list and make it visible:

ACTIVATE: To make the airspace active, click MENU / Settings / Files / Airspace …, then scroll until you see the file you want to make active and click on the box to insert a check mark to activate that file.

MAKE VISIBLE: The wave window may NOT be visible until you change the settings. located in the Menu / Settings / Setup Airspace section.

In the "Airspace type" box right click on the drop down list, select "Glider Sector", then select the line Width, Color, and Fill. It is recommended to select Fill Transparent or Fill 10%, otherwise the color may block the waypoints in the Wave Boundaries.

Make sure that "Show Airspace" has a check mark next to it or the Wave Window will not be visible (be sure to set up Map 1 and Map ).


SEEYOU Desktop

SeeYou desktop supports multiple airspace files in the SeeYou .cub and OpenAir .txt file format.

Download the “Wave SUA file” from the downloads section and save to a folder on your computer.

Open SeeYou, then on the top menu click Tools / Airspace and the Airspace box will open.

On the bottom of the Airspace box select Add, and navigate to the folder where the “Wave SUA file” you downloaded resides and click Open. That will load the file and it should automatically put a check mark on the left side so the file will be activated.

In the same Airspace Box, look at the list of airspace types and be sure that Glider Sector has a check mark on the left - otherwise it will not be visible on the map.

Then in the SAME Airspace box near the top you will see "Options, Item ", click on the right side down arrow, scroll down to "Glider Sector".

With "Glider Sector" in the window you then select Style (recommend Inbound Offset), Line Width, and your choice of Color.  Click OK and then check your map.  The Williams Glider Area North and South should show on the map.



WinPilot directly supports adding one or more files in open airspace format. This year’s file has not been tested, but the OpenAir file format is the same file type as the previous file so we expect it to load exactly the same.  Please report back if this is wrong.


Copy the “Wave SUA file” to a location on your PDA where WinPilot will find it. This needs to be either the WinPilot directory (default of My Documents) or the top level directory of the SD memory card. In WinPilot go to Menu>Files and click on the Additional Airspace […] button select your “Wave SUA file” . Click the up arrow button and then the OK button.


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