How low can you set your altimeter pressure...?

[Biggus]

The pressure here is currently 950mb. In the days of pre-digital cockpits most altimeters had a physical limit on how low the pressure could be set.

Is it an issue with the current generation of aircraft?

[Fareastdriver]

Some time in the early eighties at Aberdeen we flew on the regional QNH because nobody could wind down to QFE.

[C4IONMYPC]

I seem to remember that the limitation on Barometric Altimeters was in the region of 28in to 31in on yank kit or 950mb to 1050mb on our good old British stuff don't know about glass cockpit but it was all to do with the amount you could flex or compress the pressure bit inside the altimeter.

[Green Flash]

I beleive the new Met Office barometers (digital) are caliberated down to at least 890 hPa.

[LFFC]

Just who is Hector Pascal, and why are we letting a Frenchman run the weather? :8

[Arm out the window]

Particularly since he rudely muscled in and put Millie Barr out of business.

[LateArmLive]

The QFE at KAF is regularly in the 890 region - well below the limit of my old altimeter

[LFFC]

Particularly since he rudely muscled in and put Millie Barr out of business.

I don't think that he even tried to negotiate! :E

[Melchett01]

Just who is Hector Pascal

Apparently he's a black and white coloured Irish greyhound and is very good at forecasting the weather. On good flying days he can be found scratching to get out of the crewroom. On days where the weather is looking a bit iffy, he's generally found slumped by the door staring out of the window. And on days where it's really bad, he can usually be found sitting by the beer fridge barking at it.:ok:

[LFFC]

Puts me in mind of the Bungling Baron's pet whippet.

[18greens]

Surely the point is moot. If the pressure in the uk is 950 I thought your biggest issue was keeping the doors on the hangar much less worrying how to work out how high you are.

[Big Tudor]

Dusting off the brain cells, wasn't QNE used once the pressure fell off the bottom of the dial? Seem to recall it was 940 or 945mb. St. Mawgan recorded 948 during the Oct 87 storm.

[RetiredF4]

Biggus

In the days of pre-digital cockpits most altimeters had a physical limit on how low the pressure could be set.

In search of the physical limit i turned down the Smith KAA 1803 from year 1968 klick (http://buescher-flugversand.de/images/product_images/info_images/60_0.jpg) on my desk. I stopped 5.000 feet below sealevel at about 750 mbar, as my fingers turned sore.

franzl

[charlies angel]

Airbooses go down to 745mb and up to 1050/1100mb depending on MSN/type:)

[oceancrosser]

Airbooses go down to 745mb and up to 1050/1100mb depending on MSN/type

Ditto with most Boeings I have flown, but for a while we had some 737s that would only go down to 950mb. That occasionally became an issue.
Lowest I have set personally is 932mb (the center of the low pressure system was estimated at 928mb), highest 1047mb, at the same airport.

[Fareastdriver]

One of the reasons why civil airfields use QNH instead of the more logical QFE is to ensure common settings at all terrain altitudes.

[PPRuNeUser0178]

I don't know why but back in the days of the CAA ATPL exams before all this fangled euro thingy, one of the exam questions was the range of an altimeter's setting on the mb scale and the answer was 950-1050. Thanks PPSC you may be gone but you engrained some pretty useless stuff in my memory...... if only I could remember to read the wind of the ND when selecting flap 1 these days..............:ugh:

[CyclicRick]

About a Dachshund...oh sorry wrong question!:uhoh:

[handysnaks]

I think it's just a trans-gender issue! You never see Hector or Millie in the same place. If you ask me, I think they're the same ........person

[Ken Scott]

On the C130J the main (HUD) altimeter goes down to 951mb & the standby all the way down to 745mb.

[Rossian]

...was watching to co-pilot trying to zero the altimeter at Embakasi, Kenya and wondering why it took so long.

Almost as much as watching the dawning realisation on the face of the junior nav that low pressure systems rotate the other way south of the equator and that we were now going the wrong way round the dying remnants of a cyclone.

The first words of Buys Ballots law should always be voiced "In the Northern Hemisphere....."

The Ancient Mariner

[Wander00]

I always thought "in the Northern Hemishpere" was a standard part of BB's law - it was as I learned it - and my son who has qualified as a YM Ocean has learned it the same way.

[Rossian]

.....but not everyone remembers to say it. Earlier this year on hols in Oz I tried
a little experiment with "nephew-in-law"?? who holds a CPL and asked him if he'd heard of BB's law. He had but when asked to repeat it just said "if the wind's in your back the low pressure is on the right - no?"

He then got slightly cross and accused me of pedantry and said "Well, WTF does it matter anyway!!"

The yoof of today - sighs - can't tell them anything.

The Ancient Mariner

[Dr Schlong]

I believe the standby altimeter on the VC10 goes down to at least 500mb, I'm sure Beagle will know for sure!

[Thone1]

Our off-the-shelf altimeter on the S-3 goes down to 850mb.

Thomas

[Tinribs]

These two can often be seen on opposite sides of the same dial but never next toeach other, do you think she might be ,,,,, O never mind

[Courtney Mil]

Tin,

Way too deep, Man! But I see where you're going.

[foldingwings]

Mid 70s, station exercise at Honington, 12 Sqn Buccs awaiting Strike Launch, "Crews to cockpits" called 3 hours previously and Foldie and his pilot feeling incredibly bored having exhausted the potential I Spy targets from the Eastern dispersals. Bucc fitted with pedestal altimeter between Nav's knees. OK man in front, How low do you think I can wind the QFE down to?

He never got close as there was a graunching crunch as the knob came off in my hand passing 948! Thankfully, we never launched and a very sheepish Foldie had to explain to the Line Hut crew just what he had done!! As ever a crate of beer resolved any issue!

Foldie:\

[Geehovah]

I'm glad I never got that bored on Q Foldie. But of course, us Air Defenders used to go flying on QRA, ;)