Weather Bomb
Thread Starter
Joined: Dec 2013
Posts: 225
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From: UK
Weather Bomb
I see the BBC are talking about a weather bomb as being a drop of 24 hPa in 24 hours. In respect of the low pressure system about to hit NW Scotland they are expecting a weather bomb of 50 hPa and a minimum pressure of 930 hPa.
In my day we only had settings on our altimeters down to 950 hPa and I remember the initial confusion back in the early 80's amongst the helicopter operators out of ABZ when one day the QNH for altimeter settings on the track system dropped well below 950. Does the more modern glass cockpit kit cope with pressure down to 930?
In my day we only had settings on our altimeters down to 950 hPa and I remember the initial confusion back in the early 80's amongst the helicopter operators out of ABZ when one day the QNH for altimeter settings on the track system dropped well below 950. Does the more modern glass cockpit kit cope with pressure down to 930?
Joined: May 2002
Aviation Qualifications: ATP+Mil
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From: Downeast
Why would QNH not work?
Too hard on your gray matter to figure out where the ground is?
When the wheels go bump....read the number....even with QNE it odds are it will not be reading Zero anyway.
Too hard on your gray matter to figure out where the ground is?
When the wheels go bump....read the number....even with QNE it odds are it will not be reading Zero anyway.
Joined: May 2000
Posts: 268
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From: uk
I seem to remember coming across the problem of the subscale stopping at 950 many years ago (think it was on the Wessex) and we got round it by adding 37 mb to the pressure we were given and then taking 1000' off the altimeter reading. Complicated, but better than nothing.
