Hi Bob,
It's great that you enjoyed you flight across to Co. Sligo. I've been there a
couple
of times a few years ago when there was much more activity.
Btw,
Do you know what the wind speeds were coming off the mountain?
I spent 14 years based @ an airfield in the foothills of a 30 mile long mountain
range with an average height of 2000ft but the peak immediately behind my
airfield
was 2200ft. The turbulence there was ferocious at times and the airfield
owner didn't have any understanding of when it was going to be bad, he just
went up for a flight to see what it was like! As he was flying a fixed wing
microlight
it wasn't too difficult for him to handle it if there were turbs but
in my case I was flying a Flexwing & having to control a complete wing was a
different
kettle of fish! This caused me to carry out experiments to try to get
an understanding of what was going on in the vicinity of the airfield. I
purchased
a tank of helium & a large quantity of large weather type balloons. When
I'd arrive at the airfield, I would launch a balloon & observe its trajectory.
If it was smooth, I would go flying, if it was getting blown all over the place,
I wouldn't fly. This experimentation eventually led me to conclude that if
the winds off the mountain (Northerly winds) were 20mph or greater, there was
going to be turbulence (rotors) in the lee of the hills. But there was another
complication! The land where the airfield was situated was an actual peninsula
(Dingle Peninsula) & there was a large body of water on the southern side
(only 1/2 mile or so away) called 'Dingle Bay'. As the day progressed during a
warm day, the land would heat up and, in the afternoon the cold air from the
sea breeze would come ashore & mix with the Northerly Rotors coming off the
mountain.
Where that mixing took place, all hell would break loose & it would become
a nightmare for a flexwing. It was so bad that it culminated in causing me
to have a Heart Attack on Easter Monday 9th April 2007. On that day in April
2007, the airfield owner was flying ahead of me & he couldn't descend through
the turbulence with power off, so he had to apply full power & point the
aircraft
at the ground to get down & I had to do the same. At about 200ft agl, the
turbulenc!
e stoppe
d and all was calm resulting in a perfect, normal landing. That experience
taught
me how to handle it in the future, so 3 months after recovering from my 4-way
CABG (Coronary Artery Bypass Graft) I went flying again & next time I
encountered
this area of Rotor & Sea Breeze mixing I would turn around & descend below
it until I found calm air which was usually between 2 & 400ft agl and land
without incident.
Sligo Airport isn't unlike my Dingle Airfield location Bob. You have a mountain
1073ft high & the airfield is very close to the sea. There is also forestry to
the North Eastern side which create even more treacherous Rotors than mountains
because unlike Mountain Rotors which don't go all the way to the ground (with
strength), Rotors from Trees do go all the way to the ground with full strength!
--------
Seat of my pants
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