Knowing the correct altitude and when to contact ATC (VFR)

Hi, i know that if i fly IFR the ATC assigns a altitude to me. But when i fly VFR thats not the case mostly.
So how do i know at what altitude to fly and when to contact ATC to request transition?

Flying from KKIC to KMRY over SNS. So basically KKIC->SNS->KMRY
I fly VFR and stay clear of clouds 1000 feet above, 2000 sideways and 500 below.
Taking off from KKIC im in Class G airspace from 0 feet AGL to 700 feet AGL, then i enter Class E.
Class G is uncontrolled Airspace, i just need to stay clear of clouds since i fly VFR.

I climb to 2600 feet MSL. Now How do i know if this is also 700 feet AGL?
I guess i would need to know the “ground hight” in MSL, like 500, then add the 700, so i would be in Class E airspace once i reach 1200 MSL. Is this correct?

Class E airspace is controlled airspace but since im VFR and can flight at any altitude i want as long as i stay clear of clouds and below 18000 MSL, i also dont need to contact ATC, correct?

Now i enter Class G airspace again just where it says “1” on the map. But no, im still in Class E as long as im 700 feet AGL, correct? So nothing changes for me.

Later i “enter” Class D airspace (2 on the map) shortly before reaching SNS. It tells me on the map that the Class D airspace is from 0 to 2499 feet MSL. SO no im still Class E since im at 2600 i dont need to contact ATC and can fly straight over the airport…is this correct?

Now at “3” i enter Class C airspace. This Airspace is from 2500 MSL to 4200 MSL so now im no longer in Class E since im at 2600 MSL. I need to contact the Tower.

I i would have entered on the other side (blue marked stuff) and if i would have been at 1300 MSL i would still be in Class E since the Class C is between 1500 and 4200 MSL.
Can you please tell me what the “SFC” means in the red circled area?

So overall is this all correct or did i miss something here? Its really not easy to understand Airspaces and these maps / charts but i would like to so that i fly at the correct altitude.
Thanks

Actually you submit your altitude to ATC in your flightplan in IFR.
If you are using the default flight planner, that is available from the NavLog button (upper right - after you’ve made your plan on the world globe screen).
The sim will auto fill that for you if you forget.

VFR, in a controlled airspace, they will tell you what altitude to fly, elsewhere you tell ATC your intentions.

MSL is a barometrically derived height, assumed at 29.91 or 101.3kpa
Any difference in baro pressure must be taken into account, so AGL and MSL are not always the same height even at the same location, if not adjusted for the current pressure.
I hope that covers some of your points

“SFC” means surface … so that zone is from the ground up to 4200 AMSL.

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Thanks. So this is not currently working in MSFS because only when i fly IFR the ATC tells me my altitude, not when flying VFR.

But other then that, im i correct with the airspace and my altitude?

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As far as I can tell! :+1:
But remember to go into the nav log as mentioned and confirm the sim has picked the altitude you want to cruise at.

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ATC does not assign VFR altitudes in the US. Not in the sim and not in the real world. I can’t speak to other countries. It’s up to the pilot to select a safe altitude compatible with the direction of flight.

After a quick read, most of what you wrote appears correct except that you need to contact NORCAL Approach, rather than tower, 20 miles out of Monterey before entering the Class C airspace.

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Does the sim offer the option of who to contact?

Yes. If you have the ATC window open one of the options should be to Contact NORCAL Approach once you are in their airspace. Once you are tuned to their frequency the sim will give you an option to ask for Charlie airspace transition. Normally you wouldn’t have to do that. In the real world, all you need to enter Class C airpace is two-way communication. You don’t need an actual clearance like you do with Bravo airspace.

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Thanks.
So i guess i always contact approach first if i intent to land or ask for transition?
And in the real world (at least in the USA) i would not have to ask for airspace transition when entering Class C or D airspace? Only Class B?

If your intention is to land at a Class C airport, you should be contacting Approach first. Using the map in the original post it would go something like this:

Me: NORCAL Approach, Cessna N66167
APP: Cessna 66167 go ahead (He used my callsign so two-way communication has been established. I can enter the Class C airspace. If he had said “Aircraft calling, standby” I would have to remain clear of the Charlie airspace)
Me: Cessna 66167, 20 miles east Monterey, 2600, to land
APP: Cessna 167, squawk 2345

At that point, I’m on my own to enter the pattern at Monterey. Approach will give necessary traffic advisories hand me off to tower at the appropriate time.

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Hopefully I don’t get banned. :grinning:
John and Martha King have been around almost as long as I have (yes, I’m old!) and their school has been around since about 4 years after I started flying. They offer a huge amount of absolutely free videos and other things both on their school’s website and YouTube.
I’ll post a link below to some of their best videos on YouTube, and hope you find some of them helpful in understanding the many aspects of airspace (as it relates to comm, license requirement, weather requirements, etc).
I hope this helps. And if I disappear from the forum, best wishes! :grinning: :grinning: :grinning:

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That’s all good, relevant stuff.
You shouldn’t get banned or censored for it.
It also goes with the topic.

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Height above ground level (AGL) can be deducted from the elevation spot marks, these show the altitude of the ground above sea level (called elevation). And of course obstacles are also shown with their elevation above sea level. The big (blue) number shows the highest elevation in the “grid”, depending on the chart manufacturer this might already include 1000 or 2000 ft obstacle clearance.

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The barometric altimeter is showing altitude above mean sea level as long as the local QNH is set. When using 1013.25 hPa or 29.92 inHg the altimeter reads pressure altitude, unless the atmosphere is standard (ISA) pressure altitude and altitude (AMSL) are not the same. Therefore altitude is not derived from 1013.25 hPa / 29.92 inHg.

I think what you mean is that QNH is derived from the measured atmospheric pressure at field elevation (QFE) calculated back to sea level using standard atmosphere. Therefore should you actually measure the atmospheric pressure ar sea level (QFF) it will not match the QNH unless atmosphere is ISA.

The only altimeter which is reading height is the radio altimeter. Even when flying above flat terrain with an elevation of 0 ft MSL with correct QNH set, or any other (flat) terrain with QFE set, the altimeter will still not read height unless temperature is standard.

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That is exactly what I meant.
I thought I had said that, looks like you put it much better.
You constantly amaze me with your way of explanantions.
I certainly owe you my thanks!!

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Hi all,
can I ask where you get the charts - I’m in the UK and can’t seem to find anything that looks at all like the one shown :slight_smile:

Check out skyvector.com

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I got it from skyvector. But please note that this website works best in the USA and for most other countries (like the UK) much less information and charts are available there.

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