Altimetry problems and solutions.

[trafficwas2]

Hi all,
Just wondering if anyone has a few (or many) altimetry problems with answers for practice?
At the college and wanting to keep on top of study etc.
thanks in advance.
traffic was.

[Glamdring]

There are 2 main formats for altimetry questions at the college....

Format 1...

QNH = 997mb
Transition Altitude = 6000'

State the lowest flight level (transition Level) and the thickness of the transition layer.

Change the QNH as many times as you like to change the question.

Format 2...

Danger area to 7500'
QNH = 1002mb
Transition Altitude = 3000'

What's the lowest flight level available to overfly the danger area and how high above it are you.

Again change the Height of the danger area and the QNH to change the question.

[2 sheds]

...and explain in your own words the significance of the QFE in the above! Not to mention the evident confusion between TL and TA. Should have thoroughly confused the poor guy.

2 s

[stu_h]

Altimetry scenarios

Another favourite for oral boards is:

A/c A is at (eg) FL70
A/c B is at altitude (eg) 6000 on a QNH of 972

How many feet (or not) are they separated by.

Change figures to suit, and watch out for the ones where they arent separated at all

[ZOOKER]

QNH at EGLL 1005mb.
QNH at EGQL 991mb.
What is the most likely frequency of the ILS in use at EGGP?

[goatface]

QNH at EGLL 1005mb.
QNH at EGQL 991mb.
What is the most likely frequency of the ILS in use at EGGP?

25 metres and 32 Deg C. Totally bleedin obvious innit?

[ZOOKER]

goatface,
wrong! VHF Radio frequencies are usually measured in Megahertz (MHz).

[Glamdring]

Yeah, sorry. My questions should say "Transition Altitude" and not level

I've edited it now.

[wings folded]

wrong! Radio frequencies are usually measured in Megahertz (MHz).

No, only some frequencies are measured in MHz.

There are also Gigahertz, Kilohertz and even Hertz all alone, but you need to be a whale or a submarine to receive the latter

[ZOOKER]

You are on a VFR cross-country flight from EGMD, (QNH 1029mb) to EGPG (QNH 1015mb).
Due to the persistent ache in your left ankle (which has been counteracting the en-route drift) you forget to reset your altimeter.
On arrival at PG will your altimeter,
a). Under-read.
b). Over-read.
c). By how much?

[ZOOKER]

Good spot Norwich, - and don't forget Terahertz radiation!

[HEATHROW DIRECTOR]

trafficwas2.. Firstly, please excuse the idiots on here. I'm afraid we're stuck with them.... but some of us try to help.

Here's a good tip. With altimetry questions keep this in mind: When you increase the sub-scale reading, the altitude reading increases. When you decrease the sub-scale reading, the altitude reading decreases. Just keep that in mind and I hope it helps you. I was told that by an instructor 45 years ago and never had a problem with altimetry questions since..

Good luck..

[wings folded]

I don't know if HD had me in mind as one of the idiots we are stuck with, but even so, on a serious note, I offer a slight variant of his advice.

Remember that as you climb, pressure decreases. So if your altimeter stays at the same subscale and you are heading towards lower pressure, and you maintain a given height according to your altimeter ( say, 2000 feet,) you may think you are at 2000, but you may in fact be a lot lower. (About 28 feet per millibar, if I recall correctly)

It is the same principle HD speaks of, but looked at in a slightly different way.

Different folk are receptive to different ways of looking at things. So this way of looking at it might appeal more to your logic, or maybe not, but I hope it helps.

[2 sheds]

The significance of the QFE is that the danger area is based on height above the surface. You would either be given the QFE or the QNH and the height of the surface above MSL.

This is still making no sense!

[Sideshow_90]

2 sheds -
If you use QFE, you get the height above aerodrome, therefore above the surface.
If you use QNH get altitude above mean sea level, so if using then must know danger zone limits based on mean sea level...

I think?

[ZOOKER]

Where is 'Flight Level Zero'?
Name at least one ICAO EUR Region airfield where the QNH is less than the QFE?
During a normal display routine, what correction must a 'Red Arrows' pilot apply to a pressure altimeter to enable it to read accurately during the time spent flying inverted?
What altimeter setting would you use if 'climbing straight ahead on runway heading'?

[Ivor_Novello]

Aaarghh..

QFE and Danger Areas usually don't go together well !!!

If you use QFE, you get the height above aerodrome, therefore above the surface.

Aerodrome ? Surface ? There's a lot of different surfaces around the Aerodrome... which one ??

QFE is used by pilots who can't add 1000 to the airfield elevation to fly a visual circuit. For everything else there's Mastercard.. er.. QNH !!!

I suggest to whoever was looking for altimetry questions, to stay away from this thread and to Glamdring to stay off the glue I think I'll avoid flying to your airport when the pressure's low

[ZOOKER]

trafficwas,
Surely the original thread title should be:-
'Altimetry challenges and solutions'.

[Glamdring]

I've changed the QFE to QNH. (I was tired when I wrote those questions )

Here's a problem involving QFE...

ATZ from SFC-2000'
Aerodrome elevation 326'
QFE - 985mb

What's the QNH and at what altitude do you need to overfly the aerodrome to stay clear of the ATZ?

[PDF]

To the OP,

I can't help with your problems but I suggest you use the Ignore function for some people, the more you check around here the more you'll get the idea who to listen to and who to not..

Wings folded, don't think HD was referring to you!