"Graham P Davis" wrote in message
news:20150812180458.21992393@linux-is7a...
On Wed, 12 Aug 2015 08:42:46 -0700 (PDT)
Desperate Dan wrote:

If my memory serves me correctly, CBRs in the early 70s only recorded
up to 4000ft.

That's true, we had one at Wyton for evaluating when I joined in '62. At
nighttime, however, we could use Alconbury's searchlight to get the
height of cirrus!

--
Graham P Davis, Bracknell, Berks. [Retd meteorologist/programmer]
http://www.scarlet-jade.com/
I wear the cheese. It does not wear me.
Posted with Claws: http://www.claws-mail.org/



Well Graham, that reminds me...

I was at Wyton in 1958, and used to take aledade readings on the Alconbury
searchlight too. When I first noticed the spot on distant clouds to the west
I contacted the USAF there, and they kindly provided me with the
co-ordinates of the searchlight. If I remember correctly, the baseline to
Wyton was around 10 km. They used an arc-lamp that produced a very intense
beam, from which cloud heights of up to about 25000 ft could be obtained
from Wyton. At Alconbury they probably measured the height electronically,
as I later saw a similar type of American arc-lamp searchlight at Aberporth
that displayed to cloud height on a CRT.

--
Bernard Burton

Wokingham Berkshire.

Weather data and satellite images at:
http://www.woksat.info/wwp.html



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