~Old Military Pilot/CFI
~Old Military Pilot/CFI
There was an older flight instructor at my flight school who loved to say this when he would teach airspace. He was right, that’s why the VFR weather minimums regulations exist. To allow VFR pilots to fly in the same airspace as IFR pilots without hitting each other.
Regulations: Basic VFR Weather Minimums 91.155
I am not going to write the regulation. You can find an online version of it at FAR AIM 91.155. In my opinion regulations are so dry at least this one has a handy chart. I have a printer-friendly PDF version of it in case you want to download it and study it or maybe put it on your kneeboard. But let’s dive into them a bit more and try to understand why these numbers exist.
| Airspace | Flight Visibility | Distance from Clouds |
| Class A | Not Applicable | Not Applicable |
| Class B | 3 statute miles | Clear of Clouds |
| Class C | 3 statute miles | 500 feet below1,000 feet above2,000 feet horizontal |
| Class D | 3 statute miles | 500 feet below1,000 feet above2,000 feet horizontal |
| Class ELess than 10,000 feet MSL | 3 statute miles | 500 feet below1,000 feet above2,000 feet horizontal |
| At or above 10,000 feet MSL | 5 statute miles | 1,000 feet below1,000 feet above1 statute mile horizontal |
| Class G1,200 feet or less above the surface (regardless of MSL altitude). | ||
| For aircraft other than helicopters: | ||
| Day, except as provided in §91.155(b) | 1 statute mile | Clear of clouds |
| Night, except as provided in §91.155(b) | 3 statute miles | 500 feet below1,000 feet above2,000 feet horizontal |
| For helicopters: | ||
| Day | ½ statute mile | Clear of clouds |
| Night, except as provided in §91.155(b) | 1 statute mile | Clear of clouds |
| More than 1,200 feet above the surface but less than 10,000 feet MSL. | ||
| Day | 1 statute mile | 500 feet below1,000 feet above2,000 feet horizontal |
| Night | 3 statute miles | 500 feet below1,000 feet above2,000 feet horizontal |
| More than 1,200 feet above the surface and at or above 10,000 feet MSL. | 5 statute miles | 1,000 feet below1,000 feet above1 statute mile horizontal |
I want you for the sake of this explanation to think of IFR aircraft as the big jets, the airliners, the Citations, Gulfstreams, the big fast planes that are flying from big airports to big airports.
VFR aircraft, for now, will be Cessna’s and Piper’s, and Beechcraft’s. Just to make things simple and easy to explain.
We have controlled and uncontrolled airspace. Most of the flying happens in controlled airspace, especially by IFR aircraft. They usually fly from a controlled airport to another controlled airport with minor exceptions. On the other hand we VFR planes fly from uncontrolled to controlled or uncontrolled to uncontrolled or controlled to controlled. So it’s safe to say that controlled airspace has the most traffic and the most congestion and therefore will have the greater cloud distances and flight visibility requirements.
VFR Weather Minimums in Class A
There is no VFR traffic allowed in Class A airspace, therefore there are no VFR weather minimums. That one is easy, IFR only.
VFR Weather minimums in Class B
To enter class B airspace you need to be cleared in by ATC and you have to have a working transponder. This allows ATC to know where we are at all times, however, it is still our responsibility as VFR pilots to see and avoid. Since everyone is in contact with ATC there is a lower risk of surprises popping out of clouds which is why they have 3 SM visibility and clear of clouds is the weather minimum for class B airspace. There shouldn’t be much of a need to deviate from your assigned heading to avoid another aircraft that popped out of a cloud.
Note: Remember these are the legal minimums, it doesn’t have to be your personal minimums—more on that in a bit.
VFR Weather minimums in Class C and Class D
The only thing needed to enter class C and class D is to establish two-way radio communications with the controlling agency. It would likely be ATC for class C or the tower for class D. There’s more reliance on pilots to see and avoid while flying in and out of Class C and D, we can’t be too close to clouds anymore. Our minimums are now 3-152. 3SM visibility. 1000 feet above, 500 feet below, and 2000 feet horizontally.
VFR Weather Minimums in Class E airspace
This is where the majority of your time will be spent when flying, in class E. Outside of the airport environment, there’s a really good chance that you will be in class E airspace. There are two different minimums to Class E. Below 10,000’ MSL and above 10,000 MSL.
Let’s go back to our IFR traffic. IFR traffic above 10,000’ MSL is going fast that means you need to be able to see them further away to be able to get out of their way. Our minimums have now increased to 5-111. 5SM visibility 1000’ Above the clouds, 1000’ below, and 1SM horizontally.
Above 10,000’ MSL we have big jets flying around at let’s say 350 knots. As we fly around in our 172 next to the clouds, we have to think to ourselves, “if a jet pops out of this cloud, do I have enough time to get out of the way without nose diving it to the ground?”
Below 10,000 MSL in class E airspace there is a speed limit on all aircraft of 250 knots. So our minimums are now back to the usual 3-152. 3SM visibility. 1000 feet above, 500 feet below, and 2000 feet horizontally.
VFR Weather Minimums in Class G
This is the weather minimums that change a lot and can be confusing to remember, but let’s see why they change first and then I will try to give you a diagram to help you remember all the different minimums for class G.
There are 3 layers to class G airspace surface to 1200’ AGL, 1200’ AGL to 10,000 MSL, and 10,000 MSL up to but not including 14,500’ MSL. And then there is day and night to each one.
Starting at the top from 10,000’ MSL up to but not including 14,500’ MSL the same reasoning applies as with class E. There are fast airplanes and we need to be able to respond quickly if a big airliner is coming at us. So it’s still 5-111. 5SM visibility 1000’ Above the clouds, 1000’ below and 1SM horizontally. And that goes for both day and night.
Below 10,000 MSL, the FAA seems to think that our chances of encountering a larger jet in uncontrolled airspace is les likely and they have a point, I haven’t seen very many airlines flying around in uncontrolled airspace unless they were landing or taking off at a smaller airfield. So the weather minimums are lower in the daytime. From the surface to 1,200 AGL it’s 1SM and Clear of Clouds 1COC. Above 1,200 but below 10,000 MSL it’s 1 – 152. 1SM visibility. 1000 feet above, 500 feet below, and 2000 feet horizontally. Again this is for daytime.
At night it changes because it’s a bit harder to see the clouds and obstacles at night so the FAA raised the limits 3-152 from the surface to 10,000 MSL. 3SM visibility. 1000 feet above, 500 feet below, and 2000 feet horizontally.
The easiest way I found to memorize it is to draw this, it just simplified it for me. I would draw this square and just fill in the blanks as I was waiting for flights, and before you know it you will have it memorized too.
Special VFR Weather Minimums
There might be times when you need to skirt past the clouds to get back into the airport to land or take off. You can always ask for a special VFR in that case your VFR weather minimums go down to 1SM – COC during the daytime. However to do this, you must have clearance from ATC, this means you can only do this in controlled airspace.
At nighttime you can still ask for a special VFR but and this is a big but you have to be instrument rated and flying in an instrument rated airplane, so what’s the point.
How do you determine what the visibility is?
If you are near an airport you can always listen to the ATIS and it will tell you the ground visibility, it’s usually similar in the air near the airport. However, if you aren’t near an airport you can try some exercises next time you are flying around and using your sectional or digital app. Start taking note of distances from yourself to landmarks and seeing what 3 miles really is in the air vs 5 miles vs 1 mile. You will be surprised how 3 miles of visibility is not that much.
Legal vs. safe
This brings up the topic of just because it’s legal doesn’t mean it’s safe. These are the FAA’s minimums but that doesn’t mean they have to be your personal minimums when flying. I would encourage you to take a flight in marginal conditions with a CFI and see for yourself if you haven’t already and see what it’s like to fly when the visibility is at 3SM. I have been flying for almost 20 years and I will not fly VFR in anything less than 6SM. I will file an IFR flight plan instead.
How about clouds have you flown close to the clouds with a SVFR clearance? Again I would encourage you to do it with a CFI or a trusted pilot who has done it before. You can see for yourself what it’s like to fly in those conditions and then you can decide if it’s something you want to do or wait out the weather from the safety of the ground. I will only use an SVFR clearance to get back into my home airport or an airport in my area that I have flown into, I would not do it, to land at an airplane I have not been to before.
Do you have any other questions in regards to VFR weather minimums or flying in general? Feel free to leave a comment below or send me an email. I would love to hear from you.