The day started as forecast with a light NE wind and low cloud, so low that
the airfield was effectively at cloudbase. The forecast was for an improvement
in the afternoon but with a strengthening wind.
After lunch the sun appeared
briefly and then a clearance appeared to the east so we prepared the Ka-8 and
Ka-13 as we had a couple of students and a couple of visitors. We started with
the Ka-13 at 2:23 pm with a stationary cloud upwind of the airfield, heavy sink
over the winch and rotor over the approach and circuits were just 3 minutes wiih
one for 4 minutes so the Ka-8 pilots were all reluctant to fly, although a couple
elected to fly in the Ka-13 with Peter. The last of these was Phil
Hardwick just after 5 pm and he turned north at the top of the launch and it was
immediately clear to those on the ground that they had contacted wave.
Alan
called from the winch and suggested we get the Ka-8 out which we did but waited
for Peter to land as Alan did not want to fly himself.. I had also not wanted to
fly but as the conditions had obviously improved and I was next out of those who
had not flown Peter said get in so I did, after retrieving the ballast weight
from the other Ka-8.
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| Flying towards a rotor cloud. |
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| Established in wave at 2000ft |
Went through the checks and launched at 5:45. It was clear
on the launch that I was going through rotor as it was very rough and on
releasing at 1,000' in 4 knots up I got to 1,100' before turning north and went
into reduced sink with some fluctuation which were soon getting smaller and when
I was down to 1,000' again the vario started to move positively upwards an soon
settled at 4 knots later increasing to 6-7 knots. Best height here was about
3,700' in wave and I then started investigating the rotor clouds from above but
nothing but turbulance but I did verify strong sink downwind of them so not a
place to go!
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| Line of rotor clouds over Lydford from around 3,000' or more. |
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| 6 Knots at 3000ft |
Back upwind and into the lift again I headed south west and then
saw what appeared to be some rotor clouds much higher up so flew under these and
found off the clock lift which had me at 4,700' in no time at all at cloudbase.
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A line of rotor clouds were the only indications of wave, there being no lenticulars.
Lydford Gorge is to the right of centre in this picture, taken from over North Brentor. |
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| 7 knots at 3400ft |
I headed towards where I thought I might find more lift but instead found
massive sink initially and afterwards I found wave but not smooth like earlier
but varying from a couple of knots to off the clock as though rotor was mixed in
with the wave lift. I suspect there was an upper wave system but with no clouds
to mark it and having been airborne for about 45 minutes it was time to return
to the airfield with enough height to check out the conditions before landing.
The presence of vehicles by the fence indicated that it may have been put up
already so I elected to land on the south side with a more into-wind angle.
Definitely a very happy hour.
Finally, thanks to all who waited on the ground
for me to come back.
Malcolm Wilton-Jones
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