Thursday, December 2, 2010

18,000 and climbing out of Avenal

With a reasonably strong front forecasted for Saturday and unpleasant weather in Los Osos in the morning, it wasn't looking too promising for thermal soaring. There was a decent chance at wave forming up though and Steve had already made the drive down from the Bay Area to tow for the day. Everyone else on the schedule dropped off, probably due to the rain in the forecast or just being out of town for the holiday.

Julie and I were headed out with the plan that at a minimum I could get some work done around the airport and she could go visit her grandmother in Fresno. As is usually the case, the best way to bring on good soaring is to set your mind on accomplishing other things. By Paso Robles, things had cleared slightly and there was just a scud layer at 6 or 7k. By Cholame, the scud was breaking up and two clearly identifiable wave bands were showing over the mountains west of Avenal. The base of the clouds looked to be about 6000 or 7000.

Looking NW from Hwy 41

With sunny conditions and clearly some wave action out there, we decided to set up the Duo and give it a go when we got to the airport. Worst case, we'd take a 5000ft tow to the mountains if that was what it took to see what was out there.

Arriving at the airport Steve was already there trying to get the gas cart hooked up to his car. Issues with an off-size hitch were holding things up. The plane was essentially empty, the jerry cans empty and the fuel cart was empty. Steve made a run with the jerry cans to Coalinga for fuel in order to get us into the air as soon as we were ready. We set up 5H and set about prepping for the flight.

The lenticulars formed and ebbed and shuffled around a bit. By 11:30 we were ready to go and had pulled 5H out to the launch area. Winds on the ground were still calm. Steve prepped the towplane and pulled it out of the shade structure. He hopped in and went to fire it up. The prop turned ever so slowly. Not a good sign. A few more cranks and it's barely turning over and won't fire. Steve hopped out and hand propped it a few times with everything off while I held the brakes. We let it sit in the sun for a bit and called Dan for any suggestions. Nothing too much that he could help with from a distance, but we hoped that a little warmth and the hand priming might get us going. Otherwise we were looking at needing to work out a jumpstart or battery charger. Steve climbed back in and cranked it over a few more times. Nothing, it was struggling just to turn over let alone have the strength to fire. With that, we decided to go old school and hand prop it. I had Steve shut everything off so I could pull the engine through a few times and get a feel for the timing of the compression stroke and make sure I was moving away from the engine at the right time. It only took one pull and the engine fired and roared to life. We were in business.

Steve taxied out and I hooked up the towline to the plane, then ran back to the glider and hooked it up. Julie was already set and ready to go so I hopped in back and got situated. Julie took the takeoff and with the crisp air we were off the ground quick and climbing well. Steve orbited the field once to give us some altitude before heading north towards the nearest lenticular. We didn't see much turbulence. I think we towed north along the low portion of the wave band and missed all the rotor that might have been around. Climbing through 2000agl our climb rate picked up. By 2500agl I was thinking that we were probably in wave and around 3800msl (3000agl) we were pretty clearly climbing way too fast for a Cessna 150 and Steve came on the radio confirming our suspicion. We released and slowed down in the lift. It wasn't too strong, but 2-3 knots and steady. We worked north up past the gravel pit and found a bit more strength in the lift so we worked that.

 Climbing through 5k we were nearly level with the base of the lennie. The climb picked up a bit more to 5knots or so and we edged around a bit to work out where the best lift was at. This climb rate held all the way through about 10k. At 12k or so there was a higher cap of cloud blowing over from upwind.

We opted to press forward and try to jump up a waveband towards the mountains. We pushed up towards Black Mountain, but didn't really connect with any decent lift.

 There was a good lenticular forming to the south down towards Orchard Peak. Julie handed over the plane to me and we headed south. I wasn't able to find any significant lift, but not much sink either. As we neared the lennie, I pressed upwind and finally connected with a bit of 2-3knot lift. We poked around in this a bit and then moved a bit farther SE and found 5knots. This started to fill in and we were able to press a bit farther south and west feeling out the lift. The route back to Avenal was still clear. The Avenal valley was staying open and clear, but up north towards Coalinga and Center Peak it was dark and looking a lot like precip was falling. We we now climbing through 12k at nearly 8 knots and the winds were picking up. Pointing into the wind was now showing groundspeeds in the teens.

Below us, the Foehn gap was open, but to the west was a lot of moisture and with every turn we kept an eye out below us for our options. To the NE the clouds were building and it looked like a solid sheet of cloud all the way to Fresno. To the East it was very clear all the way to Tehachapi. I switched on the oxygen and hoped that we'd be able to top out at 18,000. The climb was consistent just downwind of Orchard Peak. We had clear air to the East as a worst case escape route. Back towards Avenal, the valley remained clear, though the clouds were building. Climbing through 17,000 the view was spectacular. The Sierra to the East were crystal clear and we could hear a sole other glider on the frequency out of Cal City. It was a strange turn of events to be hearing someone in the Sierra Wave at 14k and knowing we were several thousand feet above them out of little ole Avenal.

Pointing straight into the wind at 45knots I could get our groundspeed down to just about zero. There appeared to have been a nearly perfect gradient for forming strong wave off of even a relatively small ridgeline like the Temblor range. At 17,750 I started to accelerate. We were still climbing at 4-5knots and I needed to get out of the strong lift before we broke any rules.

We topped out at about 17,900. Any higher and my transponder might have turned me in. It's a shame we couldn't have gone higher. I'd have pulled out the facemasks and taken it up a bit more, though the clouds were building below and with our dog in the car, we didn't need to find ourselves stuck on top with nowhere to go but East to Bakersfield. We were 5000 over pattern altitude at Tehachapi according to the flight computer and with the entire southern portion of the SJV clear we had plenty of options. We headed south for a ways. With so much altitude, it was a shame to not go a little bit farther. About 30 miles out from Avenal, we had a beautiful lenticular running the full length of the Temblor range. It looked like a milk run to go to Maricopa or Mt. Pinos. Looking back to the NW was a completely different story. Foehn gaps were filling in and our options to get back into Avenal appeared to be limited. I despite the allure of a long run at speed, I turned around and headed back upwind. Back near orchard peak it was clear that the Avenal valley was still open, but the overcast had filled in over Avenal.

Looking NW up the backside of a wave bar towards Avenal

It was time to come down unless we didn't want to land back at Avenal. We crossed over the primary wave bar and into the Avenal valley south of Hwy 41. From there, the whole valley was clear and although it was overcast at Avenal we were going to be able to get under it easily since the base was about 5k. We had to downsoar the backside of the cloud to get down. It was strange to be seeking out so much sink, but 14 miles out and 12k was a bit high for final glide.

We snuck down under the cloud deck and found the rotor set up right over the field which tossed a few things around the cockpit once or twice. Winds on the ground were SW, but not too strong so runway 13 was reasonable with a stiff right cross. We landed and rolled up to the trailer. A good way to end a great flight. That lenticular to the south will just have to wait for another day to let us explore it.

Absolutely couldn't have had this flight without Steve's support. Driving all the way down from the Bay Area and only getting a single tow in. No way to say thanks enough for that!

Photos can be found here: