By R.A. Brown
July 21, 1971
Soaring conditions occur in the Elsinore Valley in California on as high as 90% of the days throughout the year. A stimulating variety of soaring is available, including thermal soaring, shear line, ridge lift and lee waves. The type of lift varies with the season, wind direction, time of day, temperature and atmospheric instability.
The valley runs from Corona in a general south-easterly direction off the Mojave
Desert provide ridge lift over the Santa Ana Mountains. Occasionally this wind
is strong enough to create a standing wave located over Lake Elsinore which can
be entered by gaining the maximum altitude obtainable in the ridge lift over
the spur jutting out towards Rome Hill south of the lake, then penetrating
upwind in a northerly direction out over the lake. Recently additional wave
harmonics have been discovered further upwind over Railroad Canyon and over the
Perris Airport. Climbs to 12,000 feet ASL are not uncommon in these waves. Even
when the wind is blowing down the Santa Ana Mountains from the north-west it is
possible to ridge soar along the north face of the spur jutting out into the
valley toward Rome Hill.
In the fall, winter and spring, when a cold front advances across the Los Angeles Basin with a strong west to south-west wind blowing over the Santa Ana Mountains, a lee wave may form over the Elsinore Valley. The first visual indications are lenticular clouds forming in the lee of Santiago Peak and over Mount Palomar, followed by the propagation of the lenticular cloud along the valley over the lake and the airport. As the lift strengthens, the first sustainable lift in the vicinity of the airport frequently is over the south-west corner of the lake. Altitudes to 17,500 feet ASL have been attained in this wave, but it is not as strong as the Sierra Wave. Above 4000 feet ASL the lift is perfectly smooth, but below this altitude the rotor turbulence in the lee of the Santa Ana Mountains is quite severe. Because of the turbulence and down-drafts it is inadvisable to tow closer the mountains than Grand Avenue when a west wind is blowing. If contact with the primary wave cannot be made, it may be possible to save the flight by ridge soaring over the Sedco Hills, hoping for a secondary wave to develop along these hills, or to gain enough altitude for a later penetration upwind into the primary wave.
When the winds are not blowing in the winter, it is still possible to soar in thermal or shear line conditions.
The Elsinore Shear Line usually runs across the valley in the vicinity of the airport, and is formed by a south-east wind of moderate strength (usually 5 to 15 miles per hour) meeting a north-west wind of similar strength. The resulting rising curtain of air is quite narrow and turbulent, but capable of supporting a sailplane at 2000 to 4000 feet above the valley floor. The north-west wind frequently brings the Los Angeles smog down the valley with it and the abrupt termination of the wall of smog provides the sailplane pilot with a visual indication of the location of the elusive shear line. It is difficult to circle within the narrow width of the turbulent, changing shear line, and if the location of the line across the valley is marked by smog, dust devils or other sailplanes, it may be easier to sustain by fling back and forth across the valley along the shear line rather than trying to circle within it.
When the air is highly unstable during the spring, summer, or fall, as on a clear sunny day following the passage of a cold front, the shear line may extend east across the Sedco Hills, over Quail Valley, between Perris and Sun City, past Romoland, Homeland, Ryan Field, Hemet and on the Mount San Jacinto on the south side of the Banning Pass. If the humidity is high enough, there will be a line of cumulus clouds marking the tops of the thermals, and an easy trip to Banning or to Hemet and back is assured. The circling Orange County Club sailplanes mark the lift in the triangle between Quail Valley, Perris and Sun City, and the sailplanes north of Ryan Field provide similar welcome sign posts in the sky. The knowledge that tow-plane service is usually available on week-ends at both Perris and Ryan Field is reassuring. As the afternoon progresses, the shear line (with the smog to the north of it) may drift southward from a line joining Quail Valley, Perris and Lakeview toward Sun City, Winchester and Ryan Field, and even migrate as far south as Murrieta Hot Springs or Temecula. As the smog kills the thermal action around Elsinore, the sailplane pilot desiring to stay aloft until sunset must work south with the shear line, maintaining sufficient altitude to penetrate north to the home airport before sunset against the northerly wind which move to shear line to the south.
Since the wind blows towards the shear line, it is reasonable to assume that if there is a shear line, it will be downwind of the airport. Unfortunately there are not guarantees that there will be a shear line, or that it will be within towing distance of the airport, or that it will be possible to glide back upwind to the airport if lift is not found. If the wind increases from the south-east up the valley stronger than 20 miles per hour, soaring can be difficult as the strong wind will blow the thermals and shear line away. In such conditions it may be possible to sustain ridge lift over the covered reservoir on the ridge south of the town of Elsinore, but penetrating back upwind to the airport will be a problem for the lower performance sailplanes as altitude maintained over the ridge will vary from 900
On a typical sunny spring, summer or fall day the first thermals may generate in the vicinity of the bowl south-west of the airport where the morning sun warms the slopes of the Santa Ana Mountains, as early as 11:00 A. M. This area of lift usually strengthens and remains good until between 2 and 3 P.M., during which time it is advisable to work across the valley to Bundy Canyon, along the Sedco Hills or to Railroad Canyon to catch the thermals triggered by the afternoon sun. If strong lift results in altitudes up to 5000 feet ASL over the Sedco Hills, and the wind remains light, an exploratory trip east of Quail Valley is in order, particularly if the Orange County Club sailplanes can be seen circling high over Quail Valley. If this side trip is unproductive, a return to the holding pattern over the Sedco Hills Is advisable. watching for signs of the smog front drifting south over the hills north of Highway #74. If this is evident, wait until the smog front is close enough and sufficient altitude is in hand for a round trip to the northward searching for the shear line ahead of the smog. There are days when a long afternoon of soaring may be enjoyed north of Highway #74 in the triangle formed by Alberhill, Perris and Lake Matthews. Watch for cloud formations in this area.
On some spring days it is possible to thermal under cumulus clouds over the Santa Ana Mountains north-west to Santiago Peak, and south-east to Murrieta, Rancho California and Temecula. On the occasional day when the valley is filled with haze, a 3000 foot tow over the Santa Ana Mountains may be rewarded by a thermal in the clear sunny air on top of the mountains.