10/10 Clouds?

[sheppjr]

What is meant by the terms 10/10 clouds or 10/10 visability in relation to 8th Air Force bombing missions over Germany? I believe the first 10 is 10 miles visability. What does the second 10 mean?

Thanks,

Richard

[Jack Cook]

It means target completely obscured. Either scrub mission or bomb secondary.

[b29flteng]

5/10ths. cloud meant that 50% of the target area was obscured by clouds. 3/10ths. meant that 30% was obscured. 10/10ths. meant that the target was totally obscured by clouds.

[Bill Greenwood]

You can assume the "10" is percentage of sky covered, such as 10/10 is the sky completely covered by clouds, so that if you are above them at altitude you would not be able to see the ground or the target. 3/10 coverage is scattered in today's terms, 5/10 would be broken and 8/10 overcast, but with breaks. I have never read or heard of visibility referred to as 10s,it is given in miles today. For instrument flying today, a ceiling is the lowest layer of broken or more clouds.

[sheppjr]

Gentlemen,

Thanks for this educational moment. I have been looking for the answer for some time now.

Regards,

Richard

[Vessbot]

Today it's in 8ths..

0 - sky clear
1-2 few
3-4 scattered
5-7 broken
8 overcast