Cruising altitudes below 3000' AGL

cowman

cowman

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From what I understand there isn't a specific rule on this, aside from 500/1000' agl minimum altitudes but I was wondering if there were "best practices" that are used.

Where I fly, elevation is typically around 900'. When I've been flying with my CFI and we make short flights between airports he's essentially had me still follow the even/odd plus 500' rule even though we're still below 3000' AGL, which seems to make sense to me under the circumstances.

But suppose I'm trying to go to an airport under class B airspace and said airspace starts at 3600' and I'm on an easterly course. Technically I can fly at 3500' and all is well but that's less margin for error than I'd prefer. So I could go somewhere lower... 3250 or 3000. Legal but what's the best option for safety as far as collision avoidance?

Now, same scenario but the class B airspace starts at 3000' and again I'm going east. Fly 2750.... fly 2500 and watch the sky really carefully? Guess there isn't any other option is there? If terrain is at 500' I suppose one could fly 1500 too... but under a class B there are probably all sorts of obstacles to worry about then.

Again what's the best practice in these situations?
 
There is no cruising rule below 3000 AGL.
Best practice is VFR - see and avoid.
 
In some class c the controllers have dedicated VFR altitudes according to direction of flight. As an example SRQ has 1600 outbound and 2100 inbound .
 
I add 100' to the MEF on the sectional chart for altimeter error. This is my minimum cruising altitude. I keep lights on below 10K and keep our eight eyeballs looking outside. Watch for those stadium TFR's.
 
Leave enough room that you don't risk busting the B - or giving the appearance of busting the B because your altimeter and transponder don't quite agree - or get close enough that you are a problem for aircraft just inside the B.

If visibility is good, it's easier to spot the towers if you are well below the tops.

Don't expect anyone else to be flying at the east/west/500 foot altitudes, or if they are, don't expect them to be flying in the direction that matches the odd east, even west rule.
 
I personally fly an "off" altitude when below 3,000' agl.

For example, if the ground is about 2,000', if westbound I might fly 4,200' or 4,700' rather than slavishly using 4,500'.

I think the randomness in the altitude chosen ever-so-slightly reduces the chance of a midair by not crowding VFR traffic together vertically.

But it's a small thing, so do what your instructor says now, and once set free make your own decision.
 
Silly to follow +500 below 3K. Reality dictates a change from arbitrary space rules, to interacting with the real world by looking out the window rules. If you are following a highway or river stay on the right side(never mind the magenta.) That is what the helicopter pilots and other mouth breathers down low will/should be doing.
 
My first impression is to ask the instructor why he thinks and teaches the hemispheric rule below 3000 AGL is good or better than a random altitude. See and avoid is the best practice and I don't see anything that would cause me to think that a 500' rule helps any.
I'd say avoid VOR crossing altitudes near a VOR so the IFR students on approach frequency don't smash you (since no one in that plane is looking out the window) Or avoid IFR altitudes on approach fixes, which is where 135 guys are likely to be. There are many things going on below 3000' AGL that make me think that the best practice may be to avoid known local hot spots but by and large just look out the window and fly what seems good. We have a number of 2000' AGL towers within 30 miles of here is one example of an intrusion into that airspace.
I'll admit my immediate gripe was getting the sense that an instructor is more or less passing his prefernences, perhaps unexplained, off as something you will incorporate adn start applying and telling others without anyone giving any real thought or basis for it.
(It's even worse with mechanics passing on old wives tales.)
 
FastEddieB said:
I personally fly an "off" altitude when below 3,000' agl.

For example, if the ground is about 2,000', if westbound I might fly 4,200' or 4,700' rather than slavishly using 4,500'.

I think the randomness in the altitude chosen ever-so-slightly reduces the chance of a midair by not crowding VFR traffic together vertically.

But it's a small thing, so do what your instructor says now, and once set free make your own decision.
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That is also my normal practice, but last weekend on initial call for Flight following, the approach controller would have none of my stated intention to fly at 2,800. I donned my sheeple wool and dropped to 2,500. Meant to call later when I landed and educate, but forgot.
 
catmandu said:
That is also my normal practice, but last weekend on initial call for Flight following, the approach controller would have none of my stated intention to fly at 2,800. I donned my sheeple wool and dropped to 2,500. Meant to call later when I landed and educate, but forgot.
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What approach control facility was this?
 
Touring the chicago skyline I often fly about 1,700'MSL which is about 900'AGL off the shoreline. This puts me well under the Bravo, gives a great view, and I fly this altitude both north and south.
 
Apache123 said:
Touring the chicago skyline I often fly about 1,700'MSL which is about 900'AGL off the shoreline. This puts me well under the Bravo, gives a great view, and I fly this altitude both north and south.
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1700 MSL would put you about 1120' above Lake Michigan.
 
Flying below the Houston Class B 2000msl shelf, eastbound 1500 msl, or western course at 1800msl. Emphasis on looking out the window. Most of the time, they will clear me into the Class B on flight following, at or below 3000, so I try to stick to even/odd even though its not a rule at those altitudes.
 
Keep in mind that a constant altitude can change from 1000 AGL to 3000+ AGL pretty quickly in some places. That's a reason to use a hemispheric rule altitude.
 
MAKG1 said:
Keep in mind that a constant altitude can change from 1000 AGL to 3000+ AGL pretty quickly in some places. That's a reason to use a hemispheric rule altitude.
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I'm planning a flight to colorado springs next may-ish and that's something I noticed. I usually fly around 6,500' west and 7,500' east for XC, well 6'500 is pretty close to the ground out there so the ground will be coming up to meet us the further west we get (locally we're at about 750'MSL in Chicago).
 
Apache123 said:
I'm planning a flight to colorado springs next may-ish and that's something I noticed. I usually fly around 6,500' west and 7,500' east for XC, well 6'500 is pretty close to the ground out there so the ground will be coming up to meet us the further west we get (locally we're at about 750'MSL in Chicago).
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6500 is below the ground at KFLY, but not KCOS (though it's still below TPA). Plan carefully. Terrain rises FAST west of the city, and there is one 14000 foot peak not far away.

There is terrain to the north as well as west.
 
I don't really like flying less than 3,000 feet AGL for anything other than a very short hop a few miles away. But I generally stick with that for anything under 50 NM.

And I don't to follow a constant 3,000 feet AGL over terrain - I just stick with the hemispheric rule as I brush mountain tops.
 
I'll deviate from the hemispheric rule over the mountains if there is a reason to. Like, crossing over Donner Pass, the air can be a lot smoother at 9000 than it is at 8500 (westbound). It's a short enough crossing that getting up to 10500 is not really worth it on a warm day in an NA aircraft. And, there is no eastbound IFR traffic at that altitude as the MEA is 13000.

But, crossing over the coast ranges, I'll pick a hemispheric altitude at least 1000 above the highest obstruction (mountaintop radio towers aren't rare) and just stick with it.
 
I deliberately avoid the 500/1000 levels below 3000 AGL because so many other folks gravitate to them. So, around here where the elevations are generally below 500 MSL, I'm usually at something like 1800 or 2700.
 
Ron Levy said:
I deliberately avoid the 500/1000 levels below 3000 AGL because so many other folks gravitate to them. So, around here where the elevations are generally below 500 MSL, I'm usually at something like 1800 or 2700.
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Great minds think alike! In particular, I don't like to fly exactly at 3000msl for exactly that reason.
 
I told my students that keeping their heads on a swivel was especially important when <3000 AGL because traffic could be coming from any direction, perfectly legally.

Bob Gardner
 
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