Cold Altitude Correction

[apex190]

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

[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.

[photofly]

For the hemisphere rule for altitudes for direction of flight, you absolutely must not apply a cold weather correction.

[goingnowherefast]

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.

[Rockie]

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.

[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.

[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

[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.

[Adam Oke]

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". .

[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.

[CpnCrunch]

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.

[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.

[apex190]

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

[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

[lownslow]

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.

[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.

[AuxBatOn]

For exactly what rational reason would you NOT correct for cold temperature?! It is sometimes quite significant...

[apex190]

i know someone who failed their IFR because they did not correct in a VFR circuit.

[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...

[bobm]

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.

[goingnowherefast]

For exactly what rational reason would you NOT correct for cold temperature?! It is sometimes quite significant...

I can't think of any valid reason not to use cold weather corrections for IFR procedures. Just because it's legal, doesn't mean it's smart.

Maybe training, screaming VFR, with a training pilot looking outside and you'd rather practice the procedures than read the little chart while burning through $250/hr in that old twin you rented. But then you aren't actually IFR anyway. Obstacle clearance is by visual means.

For VFR circuits, I can see the damn ground! Just don't fly into it! No temperature corrections required.

[springlocked]

Here is another fly in the ointment LPV approach mins do not require temp correction -- also if one is doing a missed approach and are going to add temperature corrections it's in your best interest to advise ATC of the indicated altitude you are correcting to. For "on the fly thinking" remember min altitudes are just that and as long as you correct on the "fat" side all is good. I piss my pants when I see guys go to the temperature correction chart and start calculations to the 3rd decimal point. Just round up to the nearest 100 feet and for higher altitudes get an idea of what how the scale works are round up by 500 or 1000 feet. It's like doing a procedure in clear air above the clouds and ice. Approach maneuvering altitudes are just that. Not a fixed altitude you must be at. You can use any altitude you want as long as you are either cleared for it or in uncontrolled airspace.

[photofly]

i know someone who failed their IFR because they did not correct in a VFR circuit.

If they're on an IFR ride, they're not flying a VFR circuit. You might be thinking of a circling approach at minimums, which of course you must correct. If you don't, yes, grade of 1 for causing actual danger to ththe aircraft and FAIL.

[Edo]

Here is another fly in the ointment LPV approach mins do not require temp correction --.

Please explain and provide a reference. LPV is flown to baro minima so why don't you need temp corrections

[AOW]

Here is another fly in the ointment LPV approach mins do not require temp correction

Do you have a reference for that? If doesn't make sense to me, since the minimums are still based on the barometric altimeter, which is subject to temperature errors.