Sail Plane
Flight Crew Glider
Situational Awareness; Time Pressure
Inflight Event / Encounter Unstabilized Approach; Inflight Event / Encounter VFR In IMC; Inflight Event / Encounter Weather / Turbulence
Flight Crew Took Evasive Action; General Evacuated
Human Factors; Weather
With the exception of the higher levels of moisture in the forecast; the day looked to be a very strong wave day; with the mountain-top wind speeds dipping down to 37mph directly out of the west; with a very favorable wind gradient that seemed stable all the way up from a mid-level tow to 35 or 40k feet. The early morning forecast seemed to dim that prediction; but when another club aircraft reported that the ridge was working strong; I figured it was certainly worth a try. When I was in position and ready to launch; the weather seemed to be clearing a bit; with a visible Foehn gap appearing behind [a local mountain]; where I have had significant luck in the past catching a reliable wave. Although this was the first time in a while that I have attempted a zero-flap takeoff; the launch was arguably one of the best I have had in a while; with minimal deviation from centerline and a smooth transition into flight behind the tow plane. The turbulence on tow was quite substantial; and arguably the most challenging I have faced in this location; and maybe more so than I have faced while flying [in another location].I released at 5000 ft; just behind [a local mountain]; and headed immediately towards a Foehn Gap that seemed marginally stable; but rather small. Upon arriving at this smaller window; I decided that it was too risky to attempt to climb up in this area; as the gap appeared to be already closing. After putting in 30 degrees of flap to descend back safetly below the cloud deck; I moved slightly farther down the valley in zero sink to the much larger and better defined primary window; where I was greeted with a fantastical climb to 17;500 feet in under 20 minutes. As I was nearing FL180; I was forced to move out of the stronger lift; and so I pushed upwind in order to maintain 17.5k until the airspace could be opened. At this time; there were still multiple open holes that I could have descended through; as well as the entire east behind me was still open. While waiting in this stable configuration; I began to hear reports on the ground of precipitation moving in; as well as the cloud deck thickening and beginning to close the window. For the first several minutes; I figured that at my current altitude I would be more than able to stay aloft and avoid any issues; provided that at least a few options remained open; but as the radio calls began to increase and I was warned that the primary was closing; I decided it would be best to retreat down through the last two remaining holes in front of me and then jump back onto the ridge until conditions improved.As I dove for the hole; with sink rates averaging around 20kts and peaking at over 30kts; the primary window I was aiming for closed completely; and I was forced to divert to the last remaining window; which was farther south. Once arriving at the last remaining window at 8400 ft; I found that I was able to vividly see the foliage at the bottom of the environmental toilet bowl I was spiraling down; with very little gap between cloud base and the southern slope of [the local mountain]. I then confirmed with my Oudie flight computer that I was indeed several miles south of the peak of [the local mountain] and would be unable to reach a landable spot if I attempted to go out the bottom of this gap. For roughly the next 10 minutes; I attempted to climb out of the cloud bowl that I was in; but soon became disoriented as to the upwind and downwind sides of the quickly closing gap; and was soon unable to maintain VFR flight. After entering IFR conditions; my first reaction was to utilize the flight computer to aim my ground track vector north and east; so I would travel back into the lowest part of the valley.  Knowing that with no instrument time and no instruments available to confirm my orientation my chances of keeping the glider straight and level in a several thousand foot thick cloud cover was next to nothing; I decided to put the aircraft into a 90-degree flap benign spiral so that I could descend through the cloud deck. The [sailplane] had no issues maintaining this condition; and performed three stable spirals that allowed me to descend an additional 2000 ft down to 6000 ft MSL.As I crossed through 6400 ft MSL without seeing any sign of the cloud base; I determined that I was far more likely to spiral directly into the mountainside than I was to come out from under the cloud base with any safe exit options; as I was not below the peak heights. I then decided my safest option left was to bail out of the glider while I still had enough altitude for the canopy to open.  Prior to exiting the aircraft; I put on my survival backpack (with my log books and registration) backwards on my chest and grabbed my flight recorder off of the console; considered what I was about to actually commit; placed my right hand on my parachute D ring; and then jumped; arched; and pulled.The canopy opening was far less dramatic or painful than my previous 5 jumps; with a distinct lack of pain normally associated with being jolted upright by a strap between your thighs.  In this case; however; I had dropped rather low in the harness; and was taking most of the weight and pressure on my upper arms; making steering the canopy right difficult; and left nearly impossible. In my canopy ride to the ground; I was able to determine that I was now about 2 miles west of [the local mountain]; and began attempting to steer the canopy by pulling on the right riser. By sequencing this tension on the riser I was able to make better use of the wind; and ended up shortening my walk back to [the highway] by over a mile. I ended up landing in between two trees; about a foot from one and three feet from the other; with no hope of freeing my canopy from the top branches; so I was stuck about 30 feet up in the air. I was able to shift my position slightly by kicking the closer of the two trees to swing myself out and around in in order to grab on to one of the conveniently located branches. From this point I was able to wriggle myself out of my harness and hold myself up on one of the straps; while freeing my emergency bag with the other hand and tossing it down on the ground. I was then able to carefully slide down the tree; gather my belongings; and called [local authority for assistance]After discussing my location with the operator and them telling me that I was about 5-10 miles from my actual position; I headed down the slope slightly more than a half mile to [the highway].  At this point I called [local authority] again; and told them I was out of the woods and on [the highway]; to which they responded that there were no emergency services personnel available to pick me up; so I hitchhiked back to the [departure airport].
Reporter indicated that the glider was an inexpensive home-built model. It was located in a field with minimal damage.
The pilot of a sailplane experienced instrument conditions that led to disorientation. When unable to locate VFR conditions while in a descent; the pilot elected to parachute from the sailplane. Later the aircraft was located in a field with minimal damage.