Mussel Rock, Site Description
Mussel Rock is an amazing flying site. Behind the launches, the cliffs rise as high as 640′ MSL. The soarable cliffs extend to the north and south for a couple miles in each direction. On a good day, the winds are smooth and views of San Francisco and the greater Bay Area can be achieved.
One of the greatest features of this site is the abundant landing area that is virtually rotor free. This is because the plateau area near the launches lies behind a ridge that has a smooth edge without a sharp drop off. At the same time, the nature of the site is quite complex.
The hazards vary based on the wind direction and velocity as well as the rapid changes that can occur with the weather. On one day, the wind can be perfectly steady and 10 MPH at the low cliffs and not much more than 13 MPH up high with virtually no gust factor. On another day, the wind might be 10 MPH and W at the lower launches, but be blowing 20 MPH, some other direction, and extremely gusty at the upper cliffs.
Clear, blue, days are rare during the summer. On some days the fog can be all the way down to the beach, blocking flying completely. On others, the fog can be up above cliff level, with frequent level changes. Continuous monitoring of the fog and winds should become second nature as you fly here.
Landing in the water is not an option! There have been two drowning deaths of Paraglider Pilots at Mussel Rock. It is imperative to know where the tide is each day you fly. You can visually check the tides and how much beach is there from several vantage points between the parking lot and Walker Launch. Prior to heading to Mussel Rock to fly, you can look at this tide chart that is set for Pacifica’s beaches. Below is a full section on avoiding landing in the water and where the bailouts are. For planning and checking on conditions, there is a useful page that I created about wind and weather conditions for the Mussel Rock area with the local weather stations.
Different wind directions and velocities change how safety should be approached at the different launches and LZs. Vertical and horizontal edges act as triggers and create many hazardous rotors on the face of the Westlake cliffs and at the other connected ridges.
Mussel Rock is often a busy site. On some days paragliding pilots share the air with hang gliders as well as RC planes. In addition to the site being unregulated, not every pilot perceives the right of way rules the same. Being comfortable with such traffic and the standard rules is critical, but also being able to adapt to a breech of rules becomes necessary. All pilots should continuously fly in a predictable fashion and keep their eyes and attention proactive for other pilots and crafts.
When you begin flying any new site, get in touch with the locals and gather information. This is even more important with Mussel Rock, because of the complex nature of the site. This article, though it attempts to cover much, cannot come close to covering all of the hazards. Every day is different at a site like this, so understanding the effect of different wind directions, changing conditions, fog and other variables takes time and first hand observations.
If Mussel Rock were regulated, it would likely be a P3 site with a P2 sign off after an introductory period. When compared to other ridge soaring sites, Mussel Rock has unique factors that make it much more hazardous than others. The local club the Bay Area Paragliding Association, “BAPA“, looks after the site to promote site safety
Never fly alone. Without another person’s awareness of anything happening to you during a flight, help will not be available. The other person does not necessarily have to be a pilot. Someone just needs to be there and be aware of your presence. Awareness of risks and risk management are the keys to flying here. This site guide will cover the prominent issues related to the site, but cannot cover all of them. More important than reading this information is to get a thorough introduction to the site from a local pilot or instructor. After this, find some local pilots to join and help your grow your understanding of the site dynamics.
There have been several fatalities at the site and many serious injuries. The major risks of flying here include the following:
- Water Landing and Possibility of Drowning (Full discussion of the site, bailout LZs, necessity of hook knife, what do in a water landing. etc.)
- Sometimes the tides cover the entire beach. Other times the surf and water cover most of the beach. There are days where landing on the beach is possible, but landing at the bailout LZs above the surf zone is a much safer method. Every time you fly at Mussel Rock, prior to flying, check the beach and gain a perspective of how high the tide is.
- If you ever do land on the beach, immediately disconnect from the wing and then move the glider as far as possible from the water. If a wing is in the water, remember that it is only equipment and your primary responsibility is ensuring your safety from the water.
- Blowbacks (Discussion of methods to prevent and avoid blowbacks)
- Mussel Rock has high cliffs above lower launches. The wind gradient can create huge differences in wind velocity between launch and flights to upper cliffs. Above and behind the high cliffs are houses, roads and power lines. When the wind is strong, the mechanical turbulence in this area is extreme. Many pilots have become a victim to the high winds above the top of the ridge and have been blown back.
- Prevention methods are far less complex than those required once a blowback begins. Read this article to learn methods for continual wind speed monitoring while flying at Mussel Rock.
- Rotors (Discussion of mechanical turbulence, what causes it and some ways to perceive where it is)
- Class B Airspace The departure path for San Francisco International Airport flies directly over Mussel Rock. The ceiling for ultralight craft is 1,600 ft. (changed in 2019, was 1,500 previously). Normally it is difficult to fly this high, but in a wind shear pilots can exceed this altitude. Being in the path of a commercial jet would not only endanger you, but the jet and everyone in it. If you are flying and have the skill to fly in a wind shear, find a way to stay below 1,500 ft at Mussel Rock. North of the Westlake cliffs, the ceiling lifts to 2,100 ft.