Dartmoor Gliding Society Club News: Dartmoor Gliding News - Wednesday 10 January 2024

Welcome to the first flying day of 2024 at Brentor. Hurrah!

It had been frosty overnight. There was rotor wind at the site on arrival which was very noticeable when driving through the gate. Tea was made with the available water (frozen pipes) before Mike Bennett got some supplies from our neighbour.

Log books were out in the clubhouse and the realisation by some that they hadn't flown for not a month but six weeks. So a number of members were booked in for check flights. After the hangar was emptied, and the K-8 put back inside with two tyres weighting the wing tip (Ed: There were rotor effects inside the hangar!). Ever the optimist, Andy rigged his Libelle.

The rest of us waited for the for the forecast abating of the wind. There was a wave cloud well over the moors and a second one well back over Callington at Kit hill. So Andy would have his task cut out to climb in rotor to get to them.

I started in the winch thankful to be out of the icy, biting, wind with both cab doors tightly shut. But after warming up the winch for a second time there was a lot of waiting caused by a, rightly, cautious Duty Instructor concerned at the gusty, at times northerly, cross wind rather than the steady north east wind that had been forecast.

After a stand down for 30 minutes (Ed: Readers will be forgiven if they lose track of the number of stand downs before we finally get to fly!) I drove back to the winch and watched the sky and saw a lenticular develop.

An impressive lenticular cloud formed south of the winch

It also caught the eye of those at the launch point

After delivering the Twin Astir's belly dolly to the hangar in the the retrieve vehicle (for further inspections of the Twin Astir by Colin and visiting BGA Inspector, from Dorset Gliding Club, John Halford that were underway) the consensus was to wait again and have a cup of tea. After being suitably fortified we decided to commit aviation. I warmed up the winch again and the launch point team carried out Daily Inspections of the aircraft (Ed: Tsch! What is wrong with conducting DIs at the start of the day when the aircraft are removed from the hangar?).

And those at the hangar

Then we stood down again for 30 mins due to yet more gusty conditions. Meanwhile the lenticular south of the winch had doubled in size and was now forming above the winch. It was all so tempting. So Andy, in his Libelle, took the first launch. He reported a smooth launch to 1,750 feet with some turbulence at around 1,000 ft QFE.

Andy ready to launch

And away he goes

Despite the sunshine it was still bitterly cold and I decided not to rig due to the cold (Ed: Wimp!). The check flights in the K-13 started. The Puchacz was pegged out and chocked with tyres as the cross wind was quite severe at times and we haven't enough experience of its characteristics in crosswind conditions. The first flight was Mike Jardine and Peter for a weather check. Then Mike flew with Hugh, Mike Bennett, Richard (twice due to a cable break (Ed: You are up to date!)), Steve Fletcher, David Bourchier, John Smith, David Archer, and Phil Hardwick.

Hugh and Duty Instructor Mike ready themselves for flight (Ed: Hugh, where are your gloves?)

Hugh, trimmed out, flying slow and straight, looking for the wave

The remnants of the lenticular were still there but it was fading in strength

The wave cloud was still more pronounced to the south

Richard ready for his check flight (Ed: are you warm enough lads?)

Our new GRP single-seater, Astir CS77, DNE was kept busy by those pilots who were current: Scratch (twice), Peter, Gavin, John Allan (twice) and Malcolm (Ed: Good. DNE is starting to earn its keep).

John Allan ready to take the Astir CS 77, DNE, for a circuit

John "dive bombs" the airfield (Ed: Perhaps a proper circuit is called for next time?)

A carefully picketed Puchacz

Unfortunately no-one else managed to contact the wave. So what of Andy? In amongst the currency flights eyes were glued to smart phones watching Andy's progress on "Glide and Seek". After his launch he reported being in wave at 4,000 ft overhead Lydford which is to the north of the site. Across the launch point there were cries of excitement as Andy kept climbing. According to his height he must have been on oxygen and making good use of the "Dartmoor Wave box" which permits us to climb to Flight Level 195 (basically 19,500 feet without using a transponder). When he reached his maximum height he used it to head in to Cornwall; the Callington and Launceston region before returning to base.

This is what Andy said on the BGA Ladder site after uploading his trace:

"I had always thought it should be possible to get to the top of the wave box at Brentor and today was the proof. Had a good winch launch to 1,700 feet (thanks Gavin) and was straight into reduced sink pushed forward and contacted weak wave initial the climb was quite slow but the higher I got the better it become. I nearly abandoned the flight at about 14,000 feet as the inside of the canopy started to freeze up but some vigorous rubbing left me with a view out the front so I carried on. I could have gone higher but with the top of the wave box approaching and the OAT (Ed: Outside Air Temperature) at -26 C started my decent back into Brentor. Epic!"

Analysis of the .igc file produced by his logger by the BGA ladder software showed that Andy climbed to 50 foot short of Flight Level 195. His true maximum altitude was 19,069 QNH (Ed: Above sea level) which equates to a height gain of 17,490 feet. This comfortable exceeds a diamond height climb of 5,000 metres (16,405 feet). Andy already has his Diamond Height badge but he made a club record today for the highest height climb achieved from Brentor (19,069 ft). We think this is also another record: The most southerly diamond height achieved in UK (Ed: to be checked with the British Gliding Association).

(Ed: The only way to go higher in the wave box is to attempt the climb on a high pressure day and FL195 will be higher in absolute terms).

Andy's view of the same lenticular from just under 6,000 feet QNH

Andy's view at the edge of space just before terminating his climb (Ed: Note icy wing on the right)

The route and height gain of Andy's flight taken from the BGA ladder

St. Michael dd Rupe's church at North Brentor with indication of wave behind

At the end of the day Scratch flew with Hugh to ensure that he was current flying from the back seat prior to his visit to RNAS Culdrose on Saturday. Steve Fletcher also availed himself of the back seat and flew with Phil.