Class A airspace / "FL 600"?

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Sarah

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Sarah
Hey again,

I've just moved on to Airspace Classification, and I'm getting kind of caught up on the definition for Class A airspace. I understand the airspace extends from 18 k MSL... but I don't remember reading or learning about " Flight Level"

What exactly is FL 600? I've scoured all of my books and searched google and I still haven't been able to decipher this one.

Thanks!
 
fl600 is the top of class A
60000 ft

Class A airspace above 18000 msl up to including fl600
 
Flight level is any altitude above the transition altitude. Basically FL600 means a pressure altitude of 60,000 feet. Above FL180/18000' you change your altimeter to 29.92". This is because the "Transition Altitude" in North Amercia is 18,000' MSL.

Flight level is divided into 100' increments but always end in a 0 or 5. So it's either FL350/35,000' or FL355/35,500'

Does this help any?
 
Altitudes above 17999 msl are referred to as flight levels.
19000 feet = "Flight Level One Nine Zero"
33000 feet = "FL 330"

This is in part to remind you that altitudes above 17999 are pressure altitudes and the altimeter setting is always 29.92. If you are assigned an altitude in the flight levels, there is no altimeter setting given.

My regular cruising altitude in my company's Turbo 210 is FL230 or FL220.
My regular cruising altitude in my Aztec is 17000 or 16000 feet.
 
skyflea said:
fl600 is the top of class A
60000 ft

Class A airspace above 18000 msl up to including fl600
Click to expand...

Thanks!
Is this some sort of equation I'll need to know how to calculate?
I don't see any other mention of FL ( or, at least not yet. )
 
Sarah said:
Thanks!
Is this some sort of equation I'll need to know how to calculate?
I don't see any other mention of FL ( or, at least not yet. )
Click to expand...

It is based on the standard atmosphere setting of 29.92". So it's basically pressure altitude. This helps to adjust to regional differences in atmosphere pressure. So every aircraft, since everyone is using 29.92", has the same "error" so to speak.

It you need to know how to decipher the FL number look above at my older post.
 
your question was concerning a class alpha airspace and the fl600 is the ceiling or top of the airspace. All other mambo yambo don't apply to your question
No equation need is 60000 ft pressure altitude ( altimeter set at 29.92)
after fl600 airspace becomes class Eco again
system-july-20-2000-vfr-in-class.html
 
is nothing to calculate, fl600 is 60 000 ft pressure altitude at 60001 becomes class Eco
 
What is class Eco? Class E with more letters for the fun of it? Wrong spelling for Echo? Or some new term? Or something someone made up to sound important/stupidified like people did for racetrack=holding pattern?
 
fgcason said:
What is class Eco? Class E with more letters for the fun of it? Wrong spelling for Echo? Or some new term? Or something someone made up to sound important/stupidified like people did for racetrack=holding pattern?
Click to expand...

I guess it a new ICAO version of Echo. :D What abot the phase "Call the rabbits or I have the rabbits" The slanging for I have the strobes of the approach lighting system in sight.:D
 
craigvince said:
Altitudes above 17999 msl are referred to as flight levels.
19000 feet = "Flight Level One Nine Zero"
33000 feet = "FL 330"

This is in part to remind you that altitudes above 17999 are pressure altitudes and the altimeter setting is always 29.92. If you are assigned an altitude in the flight levels, there is no altimeter setting given.

My regular cruising altitude in my company's Turbo 210 is FL230 or FL220.
My regular cruising altitude in my Aztec is 17000 or 16000 feet.
Click to expand...

I have taken a Turbo 210 to FL110! :yikes: :D I want to try out the Flight Levels but alas the weather hasn't been open to letting us up there.
 
"Approach, Cessna 123AB checking in at FL6500"

"Cessna 123AB, contact Johnson Space Center 122.45"
 
Sarah said:
Thanks!
Is this some sort of equation I'll need to know how to calculate?
I don't see any other mention of FL ( or, at least not yet. )
Click to expand...

The reason that altitudes at 18,000' and above are referred to as flight levels is because the altimeter is supposed to be set to 29.92. Since 29.92 may not be the actual pressure setting, the resulting altitude shown (i.e. pressure altitude) may not be your true MSL altitude. As such, the term Flight Level is used.

So why do altimeters get set to 29.92 at 18k' and above? I'm guessing its because planes at that altitude are travelling long distances. As such, it is more likely that they would come from places with varying altimeter settings and be reading different altitudes on their altimeter when at the same level. Since your exact proximity to the ground isn't as important way up there, its safer to have everyone on the same altimeter setting.

P.S. Are you flying in addition to studying for ground school? I ask because the altimeter is one of those things that can be hard to grasp in theory but makes a lot more sense when you are looking at it and fiddling with the setting.
 
18,000 (in the US) is called the "transition altitude". This is where we switch from barometric corrected altimeter altitudes (roughly approximating MSL) and Flight Levels which as already pointed out are pressure altitude x 100 feet.

Note that this is roughly the elevation of the highest terrain in the US.

In Europe and other places the transition altitude is typically lower. It's typically 3000-6000 feet in Europe and like 11,000 or so in Australia.

Note that class A in ICAO isn't just coincident with above the transition altitude as well. It describes the service available, and goes to the ground in some places.
 
airguy said:
:rofl:

But come on now, let's not confuse the folks asking legitimate questions.
Click to expand...

Ok....

I got a legit question.. I think.:dunno:

The Red Bull guy who parachuted at 100,000...

1- did he need a clearence to go up that high ?

2 -did the balloon need a trandponder?

3- did he need to carry a transponder on the way down ?

4- was NASA involved in the fight in regard to airspace ?

Thanks in advance...

Ben.
 
N801BH said:
Ok....

I got a legit question.. I think.:dunno:

The Red Bull guy who parachuted at 100,000...

1- did he need a clearence to go up that high ?
Click to expand...
Clearance on an IFR flight plan or prior arrangement and approval is required to operate in Class A. I suspect the latter was done in this case.

2 -did the balloon need a trandponder?
Click to expand...
See #1.

3- did he need to carry a transponder on the way down ?
Click to expand...
See #1.

4- was NASA involved in the fight in regard to airspace ?
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NASA is not ATC, and national airspace is not relevant to space travel. It's hard (and expensive) to avoid airspace when you're orbiting at 15,000 MPH.
 
MAKG1 said:
NASA is not ATC, and national airspace is not relevant to space travel. It's hard (and expensive) to avoid airspace when you're orbiting at 15,000 MPH.
Click to expand...

What airspace are you in when in orbit?
 
roncachamp said:
What airspace are you in when in orbit?
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If you're over the US, technically, that's Class E. And you won't stay over the US for more than a few minutes in a low orbit.

But above 50 miles, the FAA does not have jurisdiction.

No feasible closed orbit is that low.
 
MAKG1 said:
If you're over the US, technically, that's Class E. And you won't stay over the US for more than a few minutes in a low orbit.

But above 50 miles, the FAA does not have jurisdiction.

No feasible closed orbit is that low.
Click to expand...

What do you base that on?
 
roncachamp said:
What do you base that on?
Click to expand...

Class E exists above Class A over the contiguous US.

"
Controlled airspace which is neither Class A, B, C nor D. (AIM 3-2-6.a) In most areas of the United States, Class E airspace extends from 1,200 feet (370 m) AGL up to but not including 18,000 feet (5,500 m) MSL, the lower limit of Class A airspace. There are areas where Class E airspace begins at either the surface or 700 AGL, these areas are used to transition between the terminal and en-route environments (around non-towered airports). These areas are designated on sectional charts. Most airspace in the United States is Class E. The airspace above FL600 is also Class E. (AIM 3-2-6.e.7)

"
 
roncachamp said:
1500 miles above the US? Does airspace exist where airborne flight is impossible?
Click to expand...

Well if you're going to pick nits (which seems to be your soup du jour) then you should go back to this statement, since I've already answered your first one.

MAKG1 said:
But above 50 miles, the FAA does not have jurisdiction.
Click to expand...
 
airguy said:
Well if you're going to pick nits (which seems to be your soup du jour) then you should go back to this statement, since I've already answered your first one.
Click to expand...

Let's go back to this one as well:
MAKG1 said:
NASA is not ATC, and national airspace is not relevant to space travel. It's hard (and expensive) to avoid airspace when you're orbiting at 15,000 MPH.
Click to expand...

How high are you when in orbit at 15,000 MPH?
 
roncachamp said:
Let's go back to this one as well:


How high are you when in orbit at 15,000 MPH?
Click to expand...

About 60 miles.

Do you have a point?

Orbiting spacecraft are not subject to national airspace. Wasn't that the question? Suborbital flight is not above 50 miles for the US. There is no general international agreement about that limit.

It has nothing to do with whether "airborne" flight is possible (whatever that means). Rocket-planes can fly at much, much higher altitudes than air breathing aircraft. The most extreme example being the space shuttle -- at what point does it transition from "spaceborne" to "airborne" during reentry? How many different ways can you answer that question? How many of them are arbitrary or semantic?
 
And how do you log this?
Click to expand...
I would log it with a picture glued to the logbook page as "There. Take that."

1500 miles above the US?
Click to expand...

It doesn't matter. No one has been that high since the early 1970's. Limping along in low earth orbit (when you can hitch a ride with old USSR hardware) is the extent of it except for the robots who blast past the moon in a day or so.

It's hard (and expensive) to avoid airspace when you're orbiting at 15,000 MPH.
Click to expand...

That's because you're not going fast enough to stay above Class A airspace for long without running an engine constantly.
 
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I can't find any "official" designation of the upper limit of airspace authority the FAA can claim. This statement is the only relevant piece I have found in the short search I've done so far...


There is no international agreement on the vertical extent of sovereign airspace (the boundary between outer space—which is not subject to national jurisdiction—and national airspace), with suggestions ranging from about 30 km (19 mi) (the extent of the highest aircraft and balloons) to about 160 km (99 mi) (the lowest extent of short-term stable orbits). The Fédération Aéronautique Internationale has established the Kármán line, at an altitude of 100 km (62 mi), as the boundary between the Earth's atmosphere and the outer space, while the United States considers anyone who has flown above 50 miles (80 km) to be an astronaut; indeed descending space shuttles have flown closer than 80 km (50 mi) over other nations, such as Canada, without requesting permission first.[1] Nonetheless both the Kármán line and the U.S. definition are merely working benchmarks, without any real legal authority over matters of national sovereignty.
"

For all practical purposes from what I can find, FAA jurisdiction above FL600 seems to fall under "Gee, we never thought about that."
 
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MAKG1 said:
About 60 miles.
Click to expand...

It's actually about 1500 miles. An altitude of 60 miles would require a velocity of about 17,600 MPH.

Do you have a point?
Click to expand...

Yes.

Orbiting spacecraft are not subject to national airspace. Wasn't that the question?
Click to expand...

No.

It has nothing to do with whether "airborne" flight is possible (whatever that means).
Click to expand...

Don't be silly, of course it does. Airspace is meaningless where airborne flight is not possible. That occurs at the von Kármán line, about 62 miles.
 
Interesting link here - http://www.americanbar.org/content/...iralty/admiralty_winter_2012.authcheckdam.pdf

where a precedent is made for maritime regulation over all airspace more than 12 vertical nautical miles up, and on page 19 it has this text...

However, within classes B, C, D, E, and G, a pilot may chose to operate under VFR or IFR. Thus, when a pilot goes above the Class A ceiling of FL600 and enters into the Class E airspace above FL600, the pilot is no longer obligated to operate IFR and can operate VFR and have no contact with ATC. While it remains possible for the pilot to continue to operate under VFR, the regulations permit VFR fight rules, which do not mandate continued ATC clearance, altitude reporting, or two-way radio communications – symbolic of the fact that United States is not exercising control over aviation activities above this altitude
Click to expand...

Getting back to the question of what did the Red Bull team do - my guess would be IFR clearance through Class A then VFR on top. Theoretically they would also require an IFR clearance for both the jumper and the descending capsule to descend back down through Class A. That would fall under "prior arrangement" I'm guessing, rather than two-way radio and transponder. There should be good precedent for this to take place, since we've been sending weather balloons above Class A since the 50's.
 
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roncachamp said:
It's actually about 1500 miles. An altitude of 60 miles would require a velocity of about 17,600 MPH.
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Look at the context and tell me how that makes any difference. I said you wouldn't stay in US airspace for very long at 15,000 MPH. Would that statement change at 17,600?

Don't be silly, of course it does. Airspace is meaningless where airborne flight is not possible. That occurs at the von Kármán line, about 62 miles.
Click to expand...

The space shuttle makes measurable lift well above the von Karman line. The von Karman line is where sustained flight becomes impossible. Not all flight.

Arbitrary. The space shuttle will fly thousands of miles downrange above the von Karman line, still making lift. In what sense is this not flying? The space shuttle can't maintain altitude aerodynamically 10 AGL. Is it not flying then?

And lift does not have to come entirely from slipstream flow either.

You've flown off on tangents. The question was whether a clearance was necessary from NASA or FAA in orbit. The answer is no.
 
airguy said:
However, within classes B, C, D, E, and G, a pilot may chose to operate under VFR or IFR. Thus, when a pilot goes above the Class A ceiling of FL600 and enters into the Class E airspace above FL600, the pilot is no longer obligated to operate IFR and can operate VFR and have no contact with ATC. While it remains possible for the pilot to continue to operate under VFR, the regulations permit VFR fight rules, which do not mandate continued ATC clearance, altitude reporting, or two-way radio communications – symbolic of the fact that United States is not exercising control over aviation activities above this altitude
Click to expand...

Who operates aircraft above that altitude over the US?
 
MAKG1 said:
Look at the context and tell me how that makes any difference. I said you wouldn't stay in US airspace for very long at 15,000 MPH. Would that statement change at 17,600?
Click to expand...

No, you said; "It's hard (and expensive) to avoid airspace when you're orbiting at 15,000 MPH."

The space shuttle makes measurable lift well above the von Karman line. The von Karman line is where sustained flight becomes impossible. Not all flight.

Arbitrary. The space shuttle will fly thousands of miles downrange above the von Karman line, still making lift. In what sense is this not flying? The space shuttle can't maintain altitude aerodynamically 10 AGL. Is it not flying then?

And lift does not have to come entirely from slipstream flow either.

You've flown off on tangents. The question was whether a clearance was necessary from NASA or FAA in orbit. The answer is no.
Click to expand...

You're floundering. It's time to move on.
 
roncachamp said:
No, you said; "It's hard (and expensive) to avoid airspace when you're orbiting at 15,000 MPH."
Click to expand...
There was a time when airspace was considered to be infinitely high, at least in terms of national sovereignty. It's not that way now because....it's not feasible to avoid overflying a hostile country while orbiting (that was as much about the Soviets -- who had a much more difficult problem -- than us).

You're floundering. It's time to move on.
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If you say so. It doesn't seem you understand what the von Karman line means physically. It doesn't mean an aircraft can't get above the line, and doesn't even mean it can't stay there.

Rote memorization and "research" by Google will only get you so far.

Can there be airspace on Mars?
 
fgcason said:
What is class Eco? Class E with more letters for the fun of it? Wrong spelling for Echo? Or some new term? Or something someone made up to sound important/stupidified like people did for racetrack=holding pattern?
Click to expand...

Sorry english is my second lenguaje but i think you are smart enough to get what i was saying.
:wink2:
 
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