Dartmoor Gliding News-Saturday 19th September 2020

 Every weather forecast gave us easterly winds at about 15knots at flying heights. This would be ideal for wave but the forecasts said no. The wind on the runway was northerly and somewhat gusty. there was signs of some wave clouds very high up and a few clouds lower down that looked suspiciously like rotor.

Photo of  the high level wave clouds taken late morning

Would today be suitable for training? Instructor Mike Jardine had Chris Maciejowski and Dave Archer on his list and I had One Day Course candidate Simon Vallance. The only way to be sure was for Mike and I to fly together to check out the conditions in the air. 

Mike likes to take selfies while I'm flying

The early stages of the launch were normal but as we passed 600 feet or so the turbulance from the suspected rotors could be felt and had me working a little harder. This was not too alarming and the launch finished at 1300 feet. Very good given the crosswind that was evident on the ground. The air seemed bouyant as we pressed eastwards through the mild rotor. Well out over the valley we contacted the wave which after a little searching gave a best beat of 4 knots but was generally 2 to 3 knots. A few passes in the very smooth wave lift did a couple of things. It had lifted us to 3000 feet and convinced us that we could construct some really meaningful lessons in these conditions. Time to go. A full airbrake decent was initially quite smooth but we encountered the rotor again at about 1800 feet. This stayed with us all the way to the runway but it was not too severe and a 60knot approach was all that was needed arriving back on the runway after 26 minutes. 

Climbing in smooth lift at 3 knots

Wave cloud over DMX

Mike authorised club flying and the first to go was Martin Broadway flying solo in his Twin Astir. Martin contacted the wave and climbed to 8000 feet above the airfield. Although he was still climbing steadily at 2 knots he decided to descend to allow his syndicate partners to fly, landing back after just 53 minutes. 

Martin relaxing after his flight.

Unfortunately, due to a broken cable the next launches were delayed and when flying resumed the wave had moved and the easy entry was gone. There was still heavy sink and rotors and after 2 attempts I decided to stop the One Day Course and Simon agreed to come back in a couple of weeks. 

One Day Course candidate Simon  Vallance

Chris Maciejowski and Mike in DMX

All the early wave activity had encourage a couple more privateers to rig. Roger Green flew in his ASW20 but was no more successful returning after just 8 minutes. Next up was Richard Roberts in his Discus. His first launch had him back in just 5 minutes. He had noticed some strong rotor lift in the bottom of the circuit near Brentor church and so he took another launch. This time he came straight back to the church from the launch and found a line of weak lift by heading NE towards Roadford Lake. As he climbed the lift got stronger and he was soon sailing above the clouds at 6000 feet above sea level (QNH) which is 5200 feet above the airfield (QFE). He returned after 51 minutes giving Martin Broadway both the longest and highest flight of the day. 

Richard's view from 6000 feet QNH

Looking down at a wave cloud from Richard's Dicus

The discus.

Today was a bit like the curate's egg; good in parts. We have no real explanation of the northerly wind on the runway which was definitely easterly at altitude but it was great fun anyway.

Thanks must go to our winch drivers who delivered good service all day.

Steve