Florida North/south hemisphere altitude rules

francisco collazos

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We had some weird altitude assignments heading into and out of Jacksonville (north/south). I've read somewhere that Florida has Odd-north and even- south due to our state being narrow and long. Does anyone know more about this?
 
Correct. I'll get altitude changes handing off between Atlanta and Jax almost every trip.
 
We had some weird altitude assignments heading into and out of Jacksonville (north/south). I've read somewhere that Florida has Odd-north and even- south due to our state being narrow and long. Does anyone know more about this?
Yes, that's how they do it there. There are other places where the hemispheric rule is not strictly adhered to, but not as dramatically as the 90 degree shift in Florida.
 
Yes, that's how they do it there. There are other places where the hemispheric rule is not strictly adhered to, but not as dramatically as the 90 degree shift in Florida.
Where would someone find this set of rules? Serious question as I plan to fly to Florida in the not too distant future.
 
I’ve never heard of this. I have heard a controller tell someone from the north that “we pretty much ignore the east / west altitude rules in Florida because it doesn’t work”.
 
Where would someone find this set of rules? Serious question as I plan to fly to Florida in the not too distant future.
You won't. It's not published anywhere in a publicly available document. Honestly its not that big of a deal, they'll ask you to if you want to move up or down 1k.
 
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How’s that work for VFR guys who know nothing about it? I haven’t heard any weird altitude requests while on flight following.
 
There is no hemispheric altitude rule for IFR operations in controlled airspace. Odd/east and even/west for almost all IFR is just a convention. So changing it for Florida doesn't change any rules, because there isn't one.
 
How’s that work for VFR guys who know nothing about it? I haven’t heard any weird altitude requests while on flight following.
Around my area (East coast, Daytona) it seems to just be a crap shoot. I've seen VFR traffic at just about any altitude going any/all directions.
 
I fly up and down the coastline often and never have been ask to change altitudes when I change directions in Georgia, so I don’t think it’s a Florida only thing.
 
For the peninsula, it’s even North bound odd South bound south of an east-west line thats roughly halfway between Gainesville and Lake City. Flying NE IFR out of Tampa I get even altitude until I hit that line and then I’m asked if I want to climb or descend to a normal odd altitude for the route of flight. The reverse happens flying SW back to Tampa— I start out even then get moved to an odd altitude somewhere past that imaginary line.
 
Been flying in Florida for 9ver ten years. It is true the east west convention does not always hold. That being said the north south variation does not always hold either. I fly regularly from south Florida to North Florida and back and have never been asked to change my assigned altitude, but my initial requested altitude has changed from the even northbound odd south bound without any clear pattern. Just my experience.
 
There is no hemispheric altitude rule for IFR operations in controlled airspace. Odd/east and even/west for almost all IFR is just a convention. So changing it for Florida doesn't change any rules, because there isn't one.
@francisco collazos
FAR 91.179 covers it. In Controlled Airspace you comply with the altitude assignment you are given by ATC. In Uncontrolled Airspace, the Hemispheric rule applies. The instances in which that applies is so rare, given how little Uncontrolled Airspace remains at altitudes compliant with FAR 91.177, that it’s pretty much an academic discussion. An academic discussion though that can give perspective. So, what are the rules ATC follows when assigning altitudes? Here is their rules…

1710913921567.png
 
The reason this came up is I was practicing some instrument flight and on the way back they gave us an altitude that was wrong for the east-west rules. We didn't think much of it until we asked for a higher altitude to get some vmc. The controller said she couldn't because she couldn't give us incorrect altitude level. We decided to ask the next controller and he said no, it was north-south rules so I shut up so we didn't sound like idiots and then looked it up at home.
 
Around my area (East coast, Daytona) it seems to just be a crap shoot. I've seen VFR traffic at just about any altitude going any/all directions.
Puppy mills. :D
 
The reason this came up is I was practicing some instrument flight and on the way back they gave us an altitude that was wrong for the east-west rules. We didn't think much of it until we asked for a higher altitude to get some vmc. The controller said she couldn't because she couldn't give us incorrect altitude level. We decided to ask the next controller and he said no, it was north-south rules so I shut up so we didn't sound like idiots and then looked it up at home.
I've filed properly and have had it changed to an improper altitude, and then have the next controller grumpily tell me I'm at a wrong altitude, pick higher or lower.....

I'm pretty convinced there is no standard and they are all doing it their own way.
 
In Controlled Airspace you comply with the altitude assignment you are given by ATC.

There is plenty of VFR flying in controlled airspace without communication with ATC. So if I’m flying through Florida on a course of 350 degrees, should I be at 4500’ or 5500’? With no ATC involvement and no NOTAM, I plan to fly at 4500’, which doesn’t comply with this unpublished and largely unknown north-odd “rule.”
 
That looks pretty odd. ;)

So what should VFR flights be doing?
VFR traffic appear to operate at any altitude regardless of VFR altitude rules. The only spot I see congestion of VFR tracks flying east and west is over 28J as they fly around the MOA and restricted airspace in the center of the state.
 
There is plenty of VFR flying in controlled airspace without communication with ATC. So if I’m flying through Florida on a course of 350 degrees, should I be at 4500’ or 5500’? With no ATC involvement and no NOTAM, I plan to fly at 4500’, which doesn’t comply with this unpublished and largely unknown north-odd “rule.”
I cannot find anything that says you should not just comply with the east/west rule in 91.159. That north/south thing is ATC procedure and is about IFR traffic. There is nothing in their ‘rules’ about VFR traffic. You fly in that sky, have you heard anything otherwise? @Salty , have you?
 
See my post #13

(Scarcasm) So a random thread on an internet site Gotcha. (/Scarcasm)

But seriously, I don’t remember ever hearing about this in the past. if this is some codified “rule” it should find its way into at least the AIM. A chart call out, etc.
 
Coming through JAX airspace this is the IFR altitudes you’ll get. In the sector above VQQ each overflight regardless of direction gets a new altitude (up or down 1000).
View attachment 126923
Yes, that seems to be what dictated my flight from Charleston to Clearwater recently. I was IFR at EVEN thousands when in JAX but going further south and west, ATC was insisting I go down to Odd. They changed my waypoint to almost south.There were areas of cumulus and turbulence that I was trying to avoid or minimize and staying at EVEN seemed better to keep me above. After delaying the altitude change as long as possible, I found myself jockeying a bit up and down with right and left deviations on the ODDS until I got more or less direct to Clearwater area to the southwest when EVEN was again OK, but lower now.
 
I cannot find anything that says you should not just comply with the east/west rule in 91.159. That north/south thing is ATC procedure and is about IFR traffic. There is nothing in their ‘rules’ about VFR traffic. You fly in that sky, have you heard anything otherwise? @Salty , have you?
I’ve never heard of this. I have heard a controller tell someone from the north that “we pretty much ignore the east / west altitude rules in Florida because it doesn’t work”.

I've filed properly and have had it changed to an improper altitude, and then have the next controller grumpily tell me I'm at a wrong altitude, pick higher or lower.....

I'm pretty convinced there is no standard and they are all doing it their own way.
 
I cannot find anything that says you should not just comply with the east/west rule in 91.159. That north/south thing is ATC procedure and is about IFR traffic. There is nothing in their ‘rules’ about VFR traffic. You fly in that sky, have you heard anything otherwise? @Salty , have you?
Have not heard anything otherwise and I'm talking to Jax regularly.
 
We may have spoken. Ever work a Musketeer that was flying so erratically that you questioned the effectiveness of Basic Med? Probably me.
Where are you based at. We have a lot of airspace and talk to a lot of planes. I’m sure we’ve spoke at some point
 
I cannot find anything that says you should not just comply with the east/west rule in 91.159. That north/south thing is ATC procedure and is about IFR traffic. There is nothing in their ‘rules’ about VFR traffic. You fly in that sky, have you heard anything otherwise? @Salty , have you?
VFR, you comply with the hemispheric rule. IFR, you comply with the altitude ATC gives you. The 91.179 IFR hemispheric rule only applies in uncontrolled airspace. ATC has its own hemispheric rule but it says ATC can modify as needed for traffic. If you look at the shape of Florida, you can see why they apply a north-south method. If you don’t know what they use, just file normally. If it’s “wrong,” they’ll ask you wither you want 1000’ higher or lower. Nothing more serious than that.
 
Coming through JAX airspace this is the IFR altitudes you’ll get. In the sector above VQQ each overflight regardless of direction gets a new altitude (up or down 1000).
View attachment 126923
I understand the reason for a N-S separation regimen, but is there any reason not to be consistent? The chart shows north odd at the top and along the east coast but south odd approaching GNV.
 
Where are you based at. We have a lot of airspace and talk to a lot of planes. I’m sure we’ve spoke at some point

Based at KGIF (Winter Haven). Orlando approach is local control but going north I usually get handed to Jax near Leesburg.

I was raised on the west side of Jax, in Wesconnett.
 
I understand the reason for a N-S separation regimen, but is there any reason not to be consistent? The chart shows north odd at the top and along the east coast but south odd approaching GNV.
You’re trying to apply logic to the the FAA….

It all has to do with LOA’s between facilities.
 
You really only notice it between JAX and ZTL centers. My understanding is that it was designed to not shift planes headed to the NE from a even to odd altitude as the coast runs slightly west of due north along FL then moves to East. It's honestly not that big of a deal and they will move you up or down as you prefer.
 
With IFR, there is no such thing in the regulations as a "wrong way" altitude in controlled airspace. During the winter, I have asked for lower "wrong way" altitudes when and been assigned them. In some instances traffic did not permit it. In another instance, I was given the requested altitude but the controller indicated I might have to change at the next sector. Filing an IFR flight plan with a "wrong way" altitude is simply a request to use it, ATC will assign an appropriate altitude that meets their requirements. Even if you file for an altitude below the MEA, ATC won't assign you one that is below the MIA for the segment being flown.
 
Been flying in Florida for 9ver ten years. It is true the east west convention does not always hold. That being said the north south variation does not always hold either. I fly regularly from south Florida to North Florida and back and have never been asked to change my assigned altitude, but my initial requested altitude has changed from the even northbound odd south bound without any clear pattern. Just my experience.
The special rules only apply to IFR. If you fly VFR you won't be affected.

When we fly from the Daytona area northward, we get asked to change somewhere in South Ga, and again in the same general area (S. Georgia) on the way back.
 
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