"updating" the altimeter on a cross country

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classicrock

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acousticguitar
while I am still a PPL in training(just passed my first "stage check", I have a question about updating the altimeter during flight

I already know that many Pilots on this website fly cross country.

for some, it maybe just under 100 miles, for others perhaps up to 1000? miles. I already know you set the altimeter at your departure airport(after listening to ATIS) and check it or change it to the setting at the destinaton airport if needed(after checking ATIS at the destination airport). yet along your route of flight, you may pass in proximity to 2 airports or perhaps 30? depending on the length of your flight.

how often are each of you checking ATIS and resetting the alitmeter(if needed)while on a cross country ?
 
Every once in a while.

I wouldn't bother to do it until either I am getting close to landing or it's been a couple hours.
 
The final authority:

"a) Each person operating an aircraft shall maintain the cruising altitude or flight level of that aircraft, as the case may be, by reference to an altimeter that is set, when operating --

(1) Below 18,000 feet MSL, to --

(i) The current reported altimeter setting of a station along the route and within 100 nautical miles of the aircraft.

(ii) If there is no station within the area prescribed in paragraph (a)(1)(i) of this section, the current reported altimeter setting of an appropriate available station; or

(iii) In the case of an aircraft not equipped with a radio, the elevation of the departure airport or an appropriate altimeter setting available before departure..."
 
Good method of you're not talking to ATC, as they'll just give you a new altimeter every once in a while, is to try to spot airports from your sectional and dial up its ATIS/AWOS check conditions and update, same deal at night with flicking the lights on and updating.
 
I'm on IFR flight plans a lot so, altitude is really important. I'll update on checking in with the next controller or at AWOS/ATIS stations along the route. On long cross countries (especially when it gets quiet) it helps to keep active, think ahead, etc. I've never been off by more than a few hundred feet a hundredth of a point of mercury here or there, but it's a good habit to get into.

If it's a short VFR flight I probably don't change it as often. But I like being busy in the cockpit. I get bored easily, so if I'm not scanning for traffic or making a radio call or cross-checking route info/instruments, etc then I'm tuning into AWOS.

Also another good habit to get into if you are on a VFR plan is to tune in the CTAF of the airports you pass by, that way you can get an idea of what's going on and where planes are that are outside your field of vision.

My radio setup when I'm NOT on FF is nearest CTAF as the active, 121.5 on monitor. If the CTAF gets too busy I'll just switch over to 121.5.
 
FastEddieB quoted the regulation on what is expected. I do what James331 suggested, I'll listen to the AWOS for the airports I fly near to or over.

When I am talking to ATC however, I will set the altimeter setting to whatever the controller tells me it is. It is quite common for controllers to give you a new altimeter setting when you check in with them.
 
Airplane: "Atlanta departure, Cessna 12345, 4,500"

Controller: "Cessna 12345, Atlanta departure, roger, (local) altimeter setting 30.14"

You will hear something similar to this every time you are transferred to a new controller/frequency. You will receive a new altimeter setting every time you are transferred to a new controller/frequency.
 
When you are on flight following each controller will give you the local alt. Setting.
 
Caramon13 said:
I'm on IFR flight plans a lot so, altitude is really important. I'll update on checking in with the next controller or at AWOS/ATIS stations along the route.
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I really don't think you want to do that on an instrument flight. ATC gives you the altimeter setting and that's what you're supposed to use. This way everyone (IFR) on the controller's screen is using the same setting and properly separated...vertically.
 
mondtster said:
FastEddieB quoted the regulation on what is expected. I do what James331 suggested, I'll listen to the AWOS for the airports I fly near to or over.
Click to expand...

I'm fortunate that my Garmin 496 has XMRadio, and I have local altimeter setting as one of the fields.

12878614734_bdec69989c_z.jpg


Makes it almost too easy!
 
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timwinters said:
I really don't think you want to do that on an instrument flight. ATC gives you the altimeter setting and that's what you're supposed to use. This way everyone (IFR) on the controller's screen is using the same setting and properly separated...vertically.
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This.
 
In addition to what's been shared, you'll hear the controller provide altimeter corrections to other aircraft as you monitor his frequency. So even if you're not actively talking to him/her, keep listening as other aircraft check in and correct as necessary.


And if you're uncertain you got the right correction dialed in, just ask them to "please repeat the current altimeter" and they will gladly do that. The controllers would prefer you verify like that versus be scared of asking and not be where you're supposed to be.
 
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hmm. I looked for an example on youtube and a vid. from my CFI came up. It's a small internet.

Anyway here is how it works.

Scroll to 1:30
You will see/hear the pilot get handed off from one center to another.
Around the 1:50 mark, he gets the next center and they provide the altimeter setting.

 
Or, fly in the flight levels and never worry about it.. :wink2:
 
Since the OP said he's ppl training I'll keep it VFR related. I set mine quite often. While on FF even if I hear ATC mention it to someone else I'll verify or update my setting. Not as a rule but I prob check it about every 20 minutes or so. This mainly comes from one of the first times I flew into a class delta during training, I didn't set my alt after getting atis an my CFi was perturbed with me so it kind of stuck with me to remember to set it. But to answer ur question, prob just when ATC tells you, like during handoffs is enough.
 
VFR and no flight following I use the Garmin weather page. It gives the nearest altimeter.

To answer OP, I check it often. Maybe every hundred miles or so ...
 
For what it is worth. I do not update when I hear center talk to other aircraft. I have in the past only to have to change it back later. Some centers cover a very large area and may be talking to aircraft 200 miles away on another frequency.

they give me altimeter updates more than I really need, best to use flight following anyway.

Life is a barrel of fun.

Ken
 
SixPapaCharlie said:
hmm. I looked for an example on youtube and a vid. from my CFI came up. It's a small internet.

Anyway here is how it works.

Scroll to 1:30
You will see/hear the pilot get handed off from one center to another.
Around the 1:50 mark, he gets the next center and they provide the altimeter setting.

Click to expand...

Did this guy train you about wearing shoulder harnesses when installed? There seems to be some on the copilot seat and rear seats, but none over his t-shirt.
 
rolivi said:
Did this guy train you about wearing shoulder harnesses when installed? There seems to be some on the copilot seat and rear seats, but none over his t-shirt.
Click to expand...

Is it required?
 
Foreflight with Stratus. Just click a nearby airport and read the METAR. It's easier than searching for a frequency and dialing it in.
 
Pilot's perogative, as a practical matter. . .
 
ksandrew said:
For what it is worth. I do not update when I hear center talk to other aircraft. I have in the past only to have to change it back later. Some centers cover a very large area and may be talking to aircraft 200 miles away on another frequency.

they give me altimeter updates more than I really need, best to use flight following anyway.

Life is a barrel of fun.

Ken
Click to expand...

Just to add to that, sometimes ATC will provide a station altimeter setting near to you.

Example "Archer 8113 Bravo, Milwaukee approach, radar contact, Oshkosh altimeter 29.93" - even though the setting is likely the same in Milwaukee as it is in Oshkosh:)

If you're VFR you almost always have access to plenty of weather reporting stations to keep the altimeter setting where it should be.
 
fiveoboy01 said:
Just to add to that, sometimes ATC will provide a station altimeter setting near to you.

Example "Archer 8113 Bravo, Milwaukee approach, radar contact, Oshkosh altimeter 29.93" - even though the setting is likely the same in Milwaukee as it is in Oshkosh:)

If you're VFR you almost always have access to plenty of weather reporting stations to keep the altimeter setting where it should be.
Click to expand...

Use the setting ATC gives you. It's not true that nearby airports have the same settings. Intervening terrain and nearby large bodies of water can make a large difference.

It's not unusual to see differences of 0.1" or more between Oakland and Livermore, especially in summer, even though they are barely 15 miles apart. This is often accompanied by a large temperature difference.
 
FastEddieB said:
Federal law, as a legal matter. . .
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I think you are correct (regulation, I believe, vs a law); but absent a Fed under the backseat, I'll pretty much wear it or not wear it, as the mood strikes me, at least when when flying alone.
 
MAKG1 said:
Use the setting ATC gives you. It's not true that nearby airports have the same settings. Intervening terrain and nearby large bodies of water can make a large difference.
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For clarification, I meant using various stations along the route when not talking to ATC. If I'm getting flight following, I stick with the setting they give me. Handoffs are frequent enough that I get a new setting every so often.
 
Sundancer said:
I think you are correct (regulation, I believe, vs a law); but absent a Fed under the backseat, I'll pretty much wear it or not wear it, as the mood strikes me, at least when when flying alone.
Click to expand...

Agreed, and that's fine*.

I just find many pilots are not aware that some good practices are also regulation/law.

Such as VFR cruising altitudes, traffic pattern direction and the topic(s) at hand.


*I just became aware that the topic had drifted away from altimeter settings and towards shoulder harness use. I was referring to the former in my post.
 
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timwinters said:
I really don't think you want to do that on an instrument flight. ATC gives you the altimeter setting and that's what you're supposed to use. This way everyone (IFR) on the controller's screen is using the same setting and properly separated...vertically.
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Nope, check 91.121.

It won't be off by much, but if I'm talking to Jacksonville approach and I'm on my way to Gainsville, I'm not using Jacksonville's altimeter setting, sorry. And that's usually what I get when I check in.

"Jax approach, Bugsmasher XXX level 5000, heading 360"
"Bugsmasher XXX Jax approach, roger, Jax altimeter 30.00"

I'll get the ATIS at Gainsville, and use that. Now, chances are the two aren't THAT far off from each other, but if I'm doing an approach I will be using the local setting (where available) or the next relevant setting referenced in the approach, making sure to adjust MDA's etc appropriately.

Also, shoulder restraints are only necessary for takeoff and landing or movement along the ground. Enroute you can use lapbelts. Read 91.107(3). Also it should be noted that only crewmembers are required to keep the belt fastened at all times in flight (safety harness at takeoff/landing only), while passengers are not.

Read 91.105.
 
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If I am flying enroute, I will use the setting ATC gives me. That way I'm using the same setting as other local enroute aircraft. When I am able to pickup my arrival Atis I will switch to that. I have never had an ATIS alt setting vary more than .02-.03 from what the arrival ATIS is but I suppose if it was dramatic I would ask. I would also think (could be wrong) that when you notify ATC you have the weather, they expect you will be using that ATIS alt from there on. Decending out through the FLs whould be an obvious exception but I don't fly there.
 
My plane is slow, so I have plenty of time to look for things to do: listen to various towers along the way, weather reports, etc.
 
As the others said don't be afraid to ask ATC, if needed. Even the big boys do! I'll occasionally ask to double check after a long greeting by ATC.

I've seen near by airports off by .25 or more especially when heading into a strong low. So don't always just randomly pick airports or set it every time ATC updates another aircraft. Like the others said, that other plane could be several 100 miles away.
 
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