Cold Altitude Correction

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apex190
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Cold Altitude Correction

Post by apex190 »

Do you use Cold Altitude Correction for VFR and for the circuit ?
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ahramin
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Re: Cold Altitude Correction

Post by ahramin »

You use cold altitude corrections any time terrain clearance is critical. VFR you should never be that close to terrain without good visibility but I suppose at night you could throw it in to determine your minimum enroute altitudes.
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photofly
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Re: Cold Altitude Correction

Post by photofly »

For the hemisphere rule for altitudes for direction of flight, you absolutely must not apply a cold weather correction.
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goingnowherefast
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Re: Cold Altitude Correction

Post by goingnowherefast »

apex190 wrote:Do you use Cold Altitude Correction for VFR and for the circuit ?
Do I personally use it? No.

It only should be used for minimum IFR altitudes. Even then it's still not required, although a really smart idea.
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Rockie
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Re: Cold Altitude Correction

Post by Rockie »

photofly wrote:For the hemisphere rule for altitudes for direction of flight, you absolutely must not apply a cold weather correction.
I agree. Plus cold weather corrections are based on local temperature from a known elevation above ground which you do not know enroute. If terrain clearance is a concern just add 1000' to your cruise altitude if you're able. If not just don't hit the ground because you're supposed to be VFR anyway.
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photofly
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Re: Cold Altitude Correction

Post by photofly »

In the circuit, if your altimeter setting comes from the airport at which the circuit is being flown, then the cold weather correction will be small. Since there isn't a fixed or mandatory altitude for circuits anyway nobody will care whether you correct for temperature, or most likely even notice.

In any situation, if given an altitude restriction by ATC, this must be obeyed as an indicated altitude and not corrected. If that gives you terrain clearance issues then maintain safe flight and advise ATC you are unable to comply.
If terrain clearance is a concern just add 1000' to your cruise altitude if you're able.
2000'. But the rule doesn't apply until 3000agl and there are no man made obstacles that tall, so complying with the cruising altitude rule should not be a concern at the same time as terrain clearance. If worried about terrain clearance you can pick any altitude up to an indicated 3000' agl.
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Adam Oke
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Re: Cold Altitude Correction

Post by Adam Oke »

Some food for thought straight from the flight test guide:
When aerodrome temperatures are 0ºC or colder, candidates are expected to apply the altitude
corrections published in the CAP - General to all minimum altitudes depicted on the approach chart
used
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photofly
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Re: Cold Altitude Correction

Post by photofly »

The OP may not be aware that the flight test guide which you quote is for the instrument rating flight test and not relevant to his question about VFR, and circuits.
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Adam Oke
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Re: Cold Altitude Correction

Post by Adam Oke »

photofly wrote:The OP may not be aware that the flight test guide which you quote is for the instrument rating flight test and not relevant to his question about VFR, and circuits.
Whoops, I read that one wrong. All this IFR studying "V's" look like "I's". :shock: .
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photofly
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Re: Cold Altitude Correction

Post by photofly »

what surprises me is that the FAA doesn't seem to place the same importance on correcting IFR minimum altitudes as TC. There's plenty of cold weather in parts of the US.
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CpnCrunch
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Re: Cold Altitude Correction

Post by CpnCrunch »

photofly wrote:what surprises me is that the FAA doesn't seem to place the same importance on correcting IFR minimum altitudes as TC. There's plenty of cold weather in parts of the US.
I think they changed that recently, so now it is mandatory for certain airports:

http://www.aopa.org/News-and-Video/All- ... Pilot/t_mm

It does seem strange that it used to be optional.
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goingnowherefast
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Re: Cold Altitude Correction

Post by goingnowherefast »

In Canada it's optional for instrument approaches as well. The CAP GEN uses the word should and not shall. Thus, legally speaking, it is a suggestion and compliance is not mandatory. Although it is a very good idea.
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apex190
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Re: Cold Altitude Correction

Post by apex190 »

So a pilot can't fail a IFR ride if he doesn't use Cold Altitude Correction?
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oldncold
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Re: Cold Altitude Correction

Post by oldncold »

here is another one to consider atc provides alt correction in terminal areas where there is radar coverage and on appproaches however if you accept vfr visual approach say on a ils you lose that correction factor at that point. point 2 if you do a contact approach and lose the runway enviroment and iniate a missed you now have no corrected cold wx correction .

example > if you are doing an ifr ride at -20c and dont brief the correction for the procedure turn, faf, and mins, depending on the examiner and how sticky they wish to be you have now pooched your ride .

cld wx corection one of my fav's to ask when newbies blow thru approach briefings in winter months // learned that from a longtime selkirk college instructor where cold wx correction and -30 really do mean your life cycg 8)
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lownslow
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Re: Cold Altitude Correction

Post by lownslow »

apex190 wrote:So a pilot can't fail a IFR ride if he doesn't use Cold Altitude Correction?
I believe this exact thing came up at the tribunal but I forget the exact circumstances... and the outcome.
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photofly
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Re: Cold Altitude Correction

Post by photofly »

Flight test standards are not the same thing as minimum legal standards at all. You can fail a flight test for missing all sorts of things that aren't "mandatory" in a general sense.
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AuxBatOn
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Re: Cold Altitude Correction

Post by AuxBatOn »

For exactly what rational reason would you NOT correct for cold temperature?! It is sometimes quite significant...
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apex190
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Re: Cold Altitude Correction

Post by apex190 »

i know someone who failed their IFR because they did not correct in a VFR circuit.
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pilotidentity
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Re: Cold Altitude Correction

Post by pilotidentity »

To answer the original post, no you do not. Vfr circuit altitude isn't that Big of a deal... :). Looks like the thread got hijacked by some IFR types...
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bobm
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Re: Cold Altitude Correction

Post by bobm »

apex190 wrote:So a pilot can't fail a IFR ride if he doesn't use Cold Altitude Correction?
The answer is no. It is that "should" vs. "shall" thing. This was pointed out at my last Check Pilot course in YOW. I will admit that I had thought it could be a fail item up until then...

Apparently the wording is going to be change but lord knows how long TC will take to do that.
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