Altimetry problems and solutions.
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trafficwas2,
An American pilot requests the QNH in inches.
Where would you find it?
The barometer at your airfield is rendered u/s.
How could you determine QNH and QFE?
An American pilot requests the QNH in inches.
Where would you find it?
The barometer at your airfield is rendered u/s.
How could you determine QNH and QFE?
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Why isn't QNE used in the UK?
What is QFF?
Explain the significance of the names adopted for the UK Altimeter Setting Regions?
Have you ever been to Barnsley?
What is QFF?
Explain the significance of the names adopted for the UK Altimeter Setting Regions?
Have you ever been to Barnsley?
Last edited by ZOOKER; 27th May 2009 at 13:28.
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Originally Posted by anotherthing
who says QNE is not used in the UK..
NB
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NBanker
I think in some aircraft (very old ones) QNE was used if the pressure was less than 950Mb (I think that was the figure - never had to use it myself - I'm not that old!). Newer Altimeters can handle this. There are still some old aircraft flying around.
You are correct, it would have to be an unusually low pressure, but Zooker's statement that it is 'not used in the UK' is factually incorrect in so much that it could feasibly be used given the right aircraft/pressure/airfield combination...
I think in some aircraft (very old ones) QNE was used if the pressure was less than 950Mb (I think that was the figure - never had to use it myself - I'm not that old!). Newer Altimeters can handle this. There are still some old aircraft flying around.
You are correct, it would have to be an unusually low pressure, but Zooker's statement that it is 'not used in the UK' is factually incorrect in so much that it could feasibly be used given the right aircraft/pressure/airfield combination...
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anotherthing,
Never heard it on the R/T, but I bow to your superior knowledge. You learn something every day!
Airfield, in T'Rossendale Valley? Ecky thump!! Does O'Leary know about this?
Never heard it on the R/T, but I bow to your superior knowledge. You learn something every day!
Airfield, in T'Rossendale Valley? Ecky thump!! Does O'Leary know about this?
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Originally Posted by Glamdring
I see your Rossendale and raise you Treborough at 1200ft amsl
Originally Posted by anotherthing
Zooker's statement that it is 'not used in the UK' is factually incorrect in so much that it could feasibly be used given the right aircraft/pressure/airfield combination...
NB
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On 22/12/1926, John Leeming and Bert Hinkler landed an Avro585 Gosport on the summit of Helvellyn (elevation 3,117ft amsl). After a short stay they returned safely to EGCD, thus forever eliminating Treborough as the highest UK 'aerodrome'.
Now I bet they used QNE!
Now I bet they used QNE!
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on the summit of Helvellyn (elevation 3,117ft amsl).
Wiki whotsit says you are right, but I was just wondering if it had sunk a little bit in the meantime.
It is quite heavy after all.
And, yes, I have been to Barnsley, and Yarmouth, and Chatham
Last edited by wings folded; 27th May 2009 at 17:15. Reason: afterthought, as usual
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wings folded,
Strangely it is not as heavy as you would expect.
Check out the results of M.H.P. Bott's 'Gravity survey of The English Lake District and Vale Of Eden (1974). - All down to an enormous Granitic intrusion, apparently.
It was 3,118 ft, but I suspect modern surveying methods are more accurate.
Hope AW doesn't spot the reduction in elevation.
Strangely it is not as heavy as you would expect.
Check out the results of M.H.P. Bott's 'Gravity survey of The English Lake District and Vale Of Eden (1974). - All down to an enormous Granitic intrusion, apparently.
It was 3,118 ft, but I suspect modern surveying methods are more accurate.
Hope AW doesn't spot the reduction in elevation.
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Hello Zooker,
I hope other dear readers will allow this slight diversion from the main topic.
It probably is not as heavy as I expect, but remains, in my view, soddin heavy. Couldn't pop it in my shopping trolley.
But you reassure me; I was starting to think that MSL had risen by one foot, perhaps. We hear so much about global warming, ice cap melting and so forth......
Is AW the great Arthur Wainwright by any chance?
I hope other dear readers will allow this slight diversion from the main topic.
It probably is not as heavy as I expect, but remains, in my view, soddin heavy. Couldn't pop it in my shopping trolley.
But you reassure me; I was starting to think that MSL had risen by one foot, perhaps. We hear so much about global warming, ice cap melting and so forth......
Is AW the great Arthur Wainwright by any chance?
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wings,
Nearly, it was actually 'Alfred' Wainwright.
You may be confusing him with William Arthur Poucher FRPS. WAP did for Lakeland photography what AW did for drawing and topographic description. Both were top men.
Poucher's books, are all out of print, but well worth sniffing out.
Oddly in 'The Lakeland Peaks', Poucher suggests that climbers should carry an 'aneroid', or altimeter.
Isn't that where we came in?
Nearly, it was actually 'Alfred' Wainwright.
You may be confusing him with William Arthur Poucher FRPS. WAP did for Lakeland photography what AW did for drawing and topographic description. Both were top men.
Poucher's books, are all out of print, but well worth sniffing out.
Oddly in 'The Lakeland Peaks', Poucher suggests that climbers should carry an 'aneroid', or altimeter.
Isn't that where we came in?
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Thanks Zooker.
No confusion with WAP; just a shoddy lapse of memory.
Wainright was born in the same town that I was.
But I fear we are becoming tedious for other readers of the thread.
So, to drag things back to the OP's question, another suggestion.
Buy an altimeter off ebay, or beg one off your flying school, or by whatever means, get hold of one.
Establish your height AMSL (OS maps help a lot).
Wait for stable anticyclonic conditions during which you can calibrate your altimeter by reference to your pressure on that day as given by the official Met.
That means set your your AMSL height on the main scale, and fiddle around with the subscale till you have the regional QNH. (You have to disconnect the subscale machanism - methods differ according to the make)
You now have a super precise barometer.
Visitors do not walk up to it and tap it.
When you get up in the morning and you see from your altimeter that your house has sunk or risen, as the case may be, but by recalibrating to your known height, you get your local QNH, but above all, you get a sense of familiarity and comfort with altimetry.
Good luck with your studies, and I hope you will be a happy and safe aircraft driver.
No confusion with WAP; just a shoddy lapse of memory.
Wainright was born in the same town that I was.
But I fear we are becoming tedious for other readers of the thread.
So, to drag things back to the OP's question, another suggestion.
Buy an altimeter off ebay, or beg one off your flying school, or by whatever means, get hold of one.
Establish your height AMSL (OS maps help a lot).
Wait for stable anticyclonic conditions during which you can calibrate your altimeter by reference to your pressure on that day as given by the official Met.
That means set your your AMSL height on the main scale, and fiddle around with the subscale till you have the regional QNH. (You have to disconnect the subscale machanism - methods differ according to the make)
You now have a super precise barometer.
Visitors do not walk up to it and tap it.
When you get up in the morning and you see from your altimeter that your house has sunk or risen, as the case may be, but by recalibrating to your known height, you get your local QNH, but above all, you get a sense of familiarity and comfort with altimetry.
Good luck with your studies, and I hope you will be a happy and safe aircraft driver.
That means set your your AMSL height on the main scale, and fiddle around with the subscale till you have the regional QNH. (You have to disconnect the subscale machanism - methods differ according to the make)
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2 sheds
When folk say "What?" to me I usually think it is one of two possibilities:
1) Lack of comprehension
2) Deafness
As we are in written form, I will rule out 2)
So, we are down to lack of comprehension.
Was it my finger / keyboard dyslexia trouble with the word "mechanism" which upset your comprehension?
Please do enlighten me.
When folk say "What?" to me I usually think it is one of two possibilities:
1) Lack of comprehension
2) Deafness
As we are in written form, I will rule out 2)
So, we are down to lack of comprehension.
Was it my finger / keyboard dyslexia trouble with the word "mechanism" which upset your comprehension?
Please do enlighten me.
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He means that being second hand the altimeter will need calibrated. This involves being at a known height and having a known QNH. You then set both of these on the altimeter (With the subscale disconnected from the main scale), reconnect the scales and voila, your altimeter is calibrated.
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He means that being second hand the altimeter will need calibrated. This involves being at a known height and having a known QNH. You then set both of these on the altimeter (With the subscale disconnected from the main scale), reconnect the scales and voila, your altimeter is calibrated.
I was genuinely confused by the rather curt response from 2 sheds, but I see that at least you comprehend.
And of course, for an aircraft mounted altimeter in active service, pilots are not authorised to do the calibration; you need a licensed engineer.
Funny that, you are trusted to fly a potentially dangerous bit of kit but cannot carry out a simple alimeter calibration....