Altimeter Setting Procedure Question

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flybrd
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Altimeter Setting Procedure Question

Unread post by flybrd » Fri Jan 19, 2018 9:45 pm

Please could anybody help me out: Questionbank and Pilotexam have different answers to this Question. I have also checked the SA AIP but still a bit confusing.

You are the pilot of an aircraft departing VFR for a cross country flight from a local gravel runway called DUPONT (FADP). Your planned cruising level is FL 65. FADP has an elevation of 3900 ft. The runway is 8 nm from Wonderboom (FAWB) aerodrome (elevation 4095 ft) but is not inside the CTR. FAWB has a transition altitude of 8000 ft. After take-off, when must you change the altimeter sub-scale setting to 1013.25 hPa?

1.Passing 5900ft?

2. When you pass a distance of 25NM from FAWB?

3. When you are not in the vicinity any longer?

4.When you exit the circuit pattern of FADP?

Assuming you reach FL65 before 25NM? So i guess airmanship will require that you change passing 5900. But the closest airport at 8NM has a Transition Altitude even though it is not listed/inside the CTR.
Last edited by flybrd on Sat Jan 20, 2018 11:14 am, edited 1 time in total.
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Re: Altimeter Setting Procedure Question

Unread post by Piggy-Hawk » Sat Jan 20, 2018 2:03 am

Seeing that no one has answered in a couple of hours, I'll give it a shot.

5900ft Seems to be the best answer, but I would have said 8000ft.

From what I understand, if an airfield is within 25nm of an airfield with a published transition altitude, that altitude has to be used, which is 8000ft in this case.

If it's beyond 25nm of that airfield, or if the airfield's transition altitude is not published, then you have to change over at 2000ft above the departing aerodome when flying VFR.

Maybe Wonderboom has a transition altitude of 8000 and that it is possibly not a published transition altitude, meaning you should switch over at 3900 + 2000 = 5900ft.

In a real life situation, if I was I was unsure, I would rather switch over sooner than later. You are only allowed to switch over above 1000ft AGL, so I would switch over as I'm climbing through 1500ft.
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Re: Altimeter Setting Procedure Question

Unread post by AOYB » Sat Jan 20, 2018 1:55 pm

http://www.caa.co.za/Aeronautical%20Inf ... s/20.2.pdf

Since Wonderboom is a listed airport, and your airport is within 25nm, you use 8000’.

See the AIC for more details
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Re: Altimeter Setting Procedure Question

Unread post by flybrd » Sat Jan 20, 2018 2:37 pm

AOYB wrote:http://www.caa.co.za/Aeronautical%20Inf ... s/20.2.pdf

Since Wonderboom is a listed airport, and your airport is within 25nm, you use 8000’.

See the AIC for more details

But the questions says the airport IS NOT LISTED. Perhaps it is one of those trick questions by the CAA.
Last edited by flybrd on Sat Jan 20, 2018 2:40 pm, edited 1 time in total.
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Re: Altimeter Setting Procedure Question

Unread post by flybrd » Sat Jan 20, 2018 2:39 pm

Piggy-Hawk wrote:Seeing that no one has answered in a couple of hours, I'll give it a shot.

5900ft Seems to be the best answer, but I would have said 8000ft.

From what I understand, if an airfield is within 25nm of an airfield with a published transition altitude, that altitude has to be used, which is 8000ft in this case.

If it's beyond 25nm of that airfield, or if the airfield's transition altitude is not published, then you have to change over at 2000ft above the departing aerodome when flying VFR.

Maybe Wonderboom has a transition altitude of 8000 and that it is possibly not a published transition altitude, meaning you should switch over at 3900 + 2000 = 5900ft.

In a real life situation, if I was I was unsure, I would rather switch over sooner than later. You are only allowed to switch over above 1000ft AGL, so I would switch over as I'm climbing through 1500ft.
This makes more sense. I think this has to do with airmanship.
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Re: Altimeter Setting Procedure Question

Unread post by AOYB » Sat Jan 20, 2018 3:08 pm

flybrd wrote:
AOYB wrote:http://www.caa.co.za/Aeronautical%20Inf ... s/20.2.pdf

Since Wonderboom is a listed airport, and your airport is within 25nm, you use 8000’.

See the AIC for more details

But the questions says the airport IS NOT LISTED. Perhaps it is one of those trick questions by the CAA.
Your airport is within 25nm of a listed airport (FAWB) so that becomes the airport of reference.
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Re: Altimeter Setting Procedure Question

Unread post by flybrd » Sat Jan 20, 2018 5:59 pm

flybrd wrote:
Piggy-Hawk wrote:Seeing that no one has answered in a couple of hours, I'll give it a shot.

5900ft Seems to be the best answer, but I would have said 8000ft.

From what I understand, if an airfield is within 25nm of an airfield with a published transition altitude, that altitude has to be used, which is 8000ft in this case.

If it's beyond 25nm of that airfield, or if the airfield's transition altitude is not published, then you have to change over at 2000ft above the departing aerodome when flying VFR.

Maybe Wonderboom has a transition altitude of 8000 and that it is possibly not a published transition altitude, meaning you should switch over at 3900 + 2000 = 5900ft.

In a real life situation, if I was I was unsure, I would rather switch over sooner than later. You are only allowed to switch over above 1000ft AGL, so I would switch over as I'm climbing through 1500ft.
This makes more sense. I think this has to do with airmanship.
If 8000ft was listed as an answer choice that would be the case. However, the questions i have come across do not have the 8000ft listed as one of the options. Above question i posted was copied from pilotexams.co.za
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Re: Altimeter Setting Procedure Question

Unread post by michael_v » Mon Jan 22, 2018 11:58 am

This is a tough one.

AIC20.2 Dated 12 Dec 2013 states:

If an airfield is within 25nm of an airfield with a published transition altitude, that altitude has to be used, which is 8000ft in this case for Wonderboom.

Departing or arriving at a non published airfield that is not within 25 Nm of a published airfield shall observe the 2000Ft rule then.

If you look at the altitude that you intend to fly at as being FL065 it will be defeating the object to climb to 8000Ft and then need to descend back down to FL065. My opinion would be to fly beyond the 25Nm of the published airfield and then at 2000Ft transition to FL065. Or request early transition from the published airfield.

Answer 2

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Re: Altimeter Setting Procedure Question

Unread post by Piggy-Hawk » Mon Jan 22, 2018 12:04 pm

michael_v wrote:
If you look at the altitude that you intend to fly at as being FL065 it will be defeating the object to climb to 8000Ft and then need to descend back down to FL065. My opinion would be to fly beyond the 25Nm of the published airfield and then at 2000Ft transition to FL065. Or request early transition from the published airfield.

Answer 2

Michael
Good catch. It never occurred to me that you won't climb to 8000ft, just to descend again to FL65.
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Re: Altimeter Setting Procedure Question

Unread post by michael_v » Mon Jan 22, 2018 12:19 pm

CAA's old trick, if you read the question correctly you should be able to get the answer right 99% of the time.

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Re: Altimeter Setting Procedure Question

Unread post by michael_v » Tue Jan 23, 2018 10:15 am

So out of interest, will we be getting the the right answer on this question?

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Re: Altimeter Setting Procedure Question

Unread post by Shepherd » Tue Jan 23, 2018 10:45 am

Also quite interested in the answer...
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Re: Altimeter Setting Procedure Question

Unread post by heisan » Tue Jan 23, 2018 11:52 am

I would say the answer is (2) - 25nm from FAWB. Within 25nm of FAWB, transition altitude is 8000', so you will cruise at 6500' (alt). Once 25nm from FAWB, transition altitude becomes 2000'AGL, so if ground level is 4500' or lower, you would then set 1013 and cruise at F065.
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Re: Altimeter Setting Procedure Question

Unread post by Segg » Tue Jan 23, 2018 12:19 pm

Considering it says this is a cross country flight, doesn't that also imply a distance greater than 8 miles (can't remember the actual figure off hand) Therefore the pilots intentions wouldn't be a local flight direct to FAWB, but to wonder out to some other location then turn towards FAWB?

Answer 2 seems right to me

What do question bank and Pilotexam say?
what goes around, comes around.
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Re: Altimeter Setting Procedure Question

Unread post by heisan » Tue Jan 23, 2018 12:28 pm

Segg wrote:Considering it says this is a cross country flight, doesn't that also imply a distance greater than 8 miles (can't remember the actual figure off hand) Therefore the pilots intentions wouldn't be a local flight direct to FAWB, but to wonder out to some other location then turn towards FAWB?

Answer 2 seems right to me

What do question bank and Pilotexam say?
Makes no difference. Transition altitude within 25nm of FAWB is 8000' no matter where you are heading.
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