lower and upper airspace

[future atco]

can someone tell me where lower airspace finishes and where upper airspace starts?

in my current job, upper air is at and above FL245, my NATS paperwork said the upper air started at FL290 and my ATC book says the split is to be FL190 from 2006 onwards?
At work we use RAS below 245 and radar control above 245,being the upper air?

i am confused as this was one of my questions at the NATS exam!

can anyone help? and please, no sarcastic replies!!! :)

[Messi]

Below Flight level 245 is lower airspace, above being upper.
John

[foghorn]

The boundary is FL245, it will be lowered to FL195 (I think) at some point in the future.

[Carbide Finger]

March 2007. Class C will be above FL195

[chiglet]

Et sur le contenant....([very] poor Froglish.)...ie Europe, Airways above FL195 are "Upper" Airways.
watp,iktch

[Lon More]

At Maastricht, it has variously been FL195 (in the Belgian Sectors), FL295 (Amsterdam Sector) and is now FL245

[future atco]

so if upper air is FL245+............why is not 2,000 seperation until FL290+??

[Lon More]

why is not 2,000 seperation until FL290+??
Historic. ICAO standard based on proven accuracy of altimetry systems. RVSM addresses this Do a gogle on it and you'll find more

[GrahamDuke]

The present position in the UK is that FL245 is the level that separates Upper and Lower airspace.

Somewhere between November 2006 and March 2007 (I believe the date has not yet been decided) the FL will be reduced to FL195 in line with most of Europe. All European airspace will eventually be the same, with FL195 being the point between Upper and Lower aispace.

Re FL290, this was the level at which vertical separation of 1,000 changed to 2,000 ie 1,000 feet below FL290, 2,000 feet above.

This, of course, has been superceded by RVSM.

Finally, Class B upper airspace has now been replaced by Class C, again this is to bring the UK into line with mainland Europe.

[songbird29]

Future atco asks : can someone tell me where lower airspace finishes and where upper airspace starts?

This question pops up periodically, and not surprisingly always by students and in relation to exams. Upper and Lower airspaces are administrative entities, without an operational meaning. So, who cares, except for the wondering student. Its only importance is in the schoolbooks and of course at some administrative desks.

Operationally important is Terminal vs Area airspace, airspace with 1000 vs2000 feet vertical separation or RVSM vs non-RVSM, airspace boundaries between sectors in a Control Facility, airspace boundaries between ATC-units, be it Upper ATC units or Lower ATC Units.

But the notion of upper and lower airpaces as such is a remnant of the past, dating back from the times that jet aircraft entered the skies and were analysed to merit a different atc regime with only a few supranational Upper ATC centres in Europe. Maastricht UAC is the only survivor of this philosophy. When the UK and France opted out, for sovereignty reasons, the make-believe of a division line between upper and lower airspace was created and has puzzled students who have the good habit of asking fundamental questions, until the day of today.

My advice to students however is to provide the answer as given in the book. No point in arguing the case with the teacher. Upper and lower airspaces figure on maps, are not harmful, give a job to a handful of administrative people around ATC and therefor will continue to be cast in stone for the foreseeable future is my guess.

[GrahamDuke]

There is a very important difference between upper and lower airspace.

In upper airspace the whole area is subject to radar control, which means that ATC can route traffic anywhere without the need to follow specific routes.

In lower airspace, radar control only applies in defined "airways" which are usually 10 miles in width, and in Terminal control areas.

Outside these airways or TC's, traffic cannot be given a full control service.

[terrain safe]

Sorry for this stupid reply but isn't below FL245 MIDDLE airspace and lower FL100 and below?

Or am I about 3000 years out of date again?:sad:

[London Mil]

ts, you are correct. Don't know why we still differentiate - apart from the usual LARS/MAS unit willy-waves at 0200 with the postie at Fl100!

[DFC]

There is a very important difference between upper and lower airspace.

In upper airspace the whole area is subject to radar control, which means that ATC can route traffic anywhere without the need to follow specific routes.

In lower airspace, radar control only applies in defined "airways" which are usually 10 miles in width, and in Terminal control areas.

Outside these airways or TC's, traffic cannot be given a full control service.

The Top of the Flight Information Region (FIR) is the base of the Upper Information Region (UIR). No difference there. The FIR from surface to FL195 or 245 or whereever the decision has been made to put the boundary. The UIR is from that boundary to an unlimited height.

The UIR will contain the Upper Control Area (UTA). This usually extends from the base of the UIR to FL660. There are no airways in the UTA simply ATS routes.

Traffic above FL660 is just like traffic in the open FIR - uncontrolled. So while there may be very few aircraft up there, they do not require an ATC clearance.

FL195 is closen by many countries for the boundary between the lower and upper airspace. This is the logical level to have the division because it is that this level that for ATS design purposes the maximum radius of turn changes from 15nm (lower airspace) to 25nm (upper airspace).

Thus it makes sense to have the airspace boundary coincident with the level at which the design of ATS routes has to change.

Regards,

DFC

[T9-ATCO]

2000 feet separation above FL245 is not provided because of the RVSM, or Reduced Vertical Separation Minima which provides 1000 feet separation for all aircraft that are RVSM approved up to FL410!!!

[MancBoy]

so how come we gave 1000 feet separation below 290 before RVSM existed?

RVSM airspace is only above 290 not 245+

[T9-ATCO]

Well, that was the nominal vertical spearation of 1000 feet bellow FL290 and 2000 feet above FL290, before RVSM was implemented, now 1000 feet is provided up to FL410 and 2000 above FL410!!! This solution was logical after the airspace became too crowded, and in that time TCAS became mandatory in all controlled airspace in order to keep it safe and efficient!!!

[MancBoy]

T9 i know

the answer i gave was in relation to you saying that rvsm airsapce is 245+ which was wrong as you correctly stated in your last post

[Pierre Argh]

Mancboy... for eyars 1000' vertical seperation F245 - F290 was standard, and 2000' applied above F290. This was based on (as said above somewhere) an almost arbitrary decision that clockwork, pressure driven altimeters lost accuracy with increasing level... so at F290 someone decided to build in a bit extra for the wife and kids...

Now some might suggest RVSM is the result of better equipment, others might say its a way to cramm more aircraft into the airspace... I think it's probably a bit of both, but with the imperrative definitely coming from the latter.

It's not unusual for operational pressure to be relieved by relaxing the rules!!!