Mt. Diablo sits rather majestically in the East Bay, one of the most recognizable features of the area. It is only a 3849 foot mountain but its isolation makes it unique. Because you can see it from such a great distance, Diablo serves as an important landmark.

There is a small group of Diablo paragliding devotees. These pilots have put many hours into the science and art of observing and interpreting the weather and flying conditions at Mr. Diablo. Here is what Bob Clem (who has 100 flying days at Diablo!) and Mahboud Zabetian, the Site Administrator, had to say about the site.

AS: What is the view like from the main launch?

MZ: Beautiful. On a clear day you can see for miles. On the right you have the spine going down to the LZ, on the left you have the ranches and a bowl.

AS: Where are the launches and what characteristics do they have?

MZ: The main launch called Juniper is at 2880 ft ASL. Nice launch, shallow drop, a lot of room for aborts. You don’t have to worry about obstructions. You DO have to worry about spectators when launching and top-landing.

BC: The upper ridge behind Juniper can be used for launches both toward the LZ, and the other direction, toward the northeast. In the latter case, fliers should steer to the left along the ridge, then wrap around the gap, heading toward the LZ. There is not much run-out space on this northeast face. There are two legal launches just below the top of the mountain: the west-facing one has a couple of hazards (an immediately adjacent chain link fence with barbed wire on top, and very little run-out space on a shallow slope), and the south-facing one needs some foliage-removal before a wing can be laid out there without snagging.

AS: What are good flying conditions and wind directions for this site?

MZ: WNW, W, WSW, SW, SSW have been good for me. I generally don’t like NW and NNW even though it is flyable.

BC: North winds can be great when they’re in the 0-6 mph range, as that seems to result in good thermal cycles up the launch face.

AS: What are some tips on how to read the conditions at the site?

MZ: Cloud cover over Diablo can be a good indicator. If the clouds are slanted or moving fast, then conditions are too strong. The direction of the slant or movement will indicate wind direction. Overdevelopment of the clouds can indicate strong thermals.

If there are no hawks flying around, then it may mean that the conditions are too bumpy or strong. Sparrows can deal with stronger winds so they are not good indicators.

BC: There is a lot of vegetation all along the main ridge extending northwest from launch. Watching for its movement will usually give the location of the small thermals moving up the slope.

AS: What are good times of the year for this site?

MZ: The best flying days are usually in the spring. Summer can be quite scary. Fall is OK.

AS: What are good times of the day for this site?

MZ: Depending on the season. Usually after 11 a.m. during the spring and fall. In the summer the heat at noon may make the conditions too strong between 12 - 3 p.m.

AS: Where are the house thermals often found?

MZ: To the left of Juniper launch over Turtle Rock Ranch. To the right of launch over the bowl before the spine. Right over the LZ.

AS: How big is the LZ and what is the glide to get to it?

MZ: It’s a large LZ but not flat. The lowest areas may be dangerous if winds are strong. The glide is long. It should be reachable by most gliders unless too much altitude was lost trying to scratch. The best strategy for someone who does not have the best glide ratio is to fly straight to the LZ and try to find thermals there. If you get over the LZ with 1000 ft. to spare, then you may have a good chance of staying up or catching a thermal.

BC: I measured and calculated the glide to the LZ: 1.6 miles out with a 1900 foot vertical works out to a 4.45:1 glide.

AS: What are some of the site hazards to look out for?

MZ: First, the spine to the North of Juniper launch going all the way down to the LZ is a good place to find thermals, but since there is often a Northerly component to the wind, getting to the ridge can be bumpy.

Second, between that ridge and the launch is a bowl, the top of which is lower than the surrounding ridges. This creates a bit of a vortex or funnel, so air moves over it faster. You may launch in slightly strong conditions, penetrate with no trouble, yet when in this area, you will have problems penetrating due to the increased airspeed.

Third, on strong days with a Northerly component in the wind, landing at the alternate LZ near Turtle Rock ranch will potentially have you in the rotor of the aforementioned spine. Landing with Big Ears may be a good idea.

Fourth, landing at the main LZ may be dangerous if the pilot tries to set down closer to the road, as that part of the LZ is lower than the upwind side and could put you in a rotor.

Fifth, scratching on light days with a low glide-ratio glider may make it impossible to land at the main LZ. Watch out for trees.

Finally, at the LZ and most everywhere, beware of stepping into ground-squirrel holes.

BC: The hills northwest of the gap can have sustained sink in a north wind over about 8 mph. This will force a landing on the long ridge called Poker Table Flat, leading down to the main LZ. At its upper end there is a barbed wire fence to avoid.

AS: What is the skill level and rating required to fly this site?

MZ: P4 and thermal experience. Pilots should be prepared to deal with surges and collapses. Just letting go of brake pressure could be an invitation for trouble.

AS: How many pilots regularly fly at this site?

MZ: The site is used consistently by 3 - 5 pilots. Other faces are seen about once a month or even once a season.

AS: What is the condition of the road to launch?

MZ: Excellent. Pilots are not supposed to park near the Juniper launch, but are supposed to park in the parking lot adjacent to the camp area and leave the parking spaces near launch for the campers.

BC: We can park at the launch parking spaces except on busy weekends when a sign may be posted indicating that Juniper parking is for overnight campers only.

AS: Are there any other important items regarding this site?

MZ: The rangers monitor the radio frequency that the hanggliders use - 144.415. In October there are many tarantulas running around the roads. It is best to avoid running over them. They are not aggressive. Finally, there is not much of a glass-off in the evenings.

BC: Other road animals besides tarantulas to steer clear of are the prairie dogs, snakes and occasional coyotes. Adhering to the 25 mph speed limit makes it fairly easy to avoid hitting these creatures.

….

So, thank you to Mahboud and Bob for providing this valuable site information on Mt. Diablo. I have just a few closing comments from my own flying at the site. If you haven’t flown there frequently it IS hard to read the conditions. One day we checked the wind in the LZ (completely dead ) and drove to the very top of the mountain (very light) to find out the true condition. Even so, we were fooled and there was a strong headwind once you were launched. I landed way up the Poker Table Flat, as Bob calls it, and got dragged on my back down the hill trying to deflate my wing. So be careful and always try to fly with those who fly the site all the time.

It is also hotter than hell at Diablo in the summertime. Be sure to bring lots of water, especially if you are hiking up to the upper launch. And don’t get annoyed and throw your glider bag on the ground when you get up the steep hill - mine rolled all the way back down to the road when I did that. And it was about 100 degrees out, or at least it felt like it!

Weather conditions appear to change quickly and to be less consistent than at other sites. Of course no site provides guaranteed conditions of any sort, but certainly Diablo seems more variable than Ed Levin or Mission, two other East Bay sites. The topography and location seem to provide more complexity at Diablo. Use caution.

And finally, there are the days when there is smooth lift everywhere and even a weany like me thinks, "Boy, if I was ever going to go cross-country, today would be the day." Of course, all of you out there will actually GO. On those days Diablo is magical and breathtaking.

And I imagine that the Diablo regulars will tell you that there are enough of the magical days, and that the challenge of the mountain makes it their favorite site! Fly safely.