when did THIS happen in aviation?

how long has it been since airports have gone from 3-to-4 letter
identifiers?

also, when did ATC go from 2000 feet vertical separation above FL290 to 1000
feet?

and, no, I was not doing time in prison for the past 20 years for
trafficking.

Retro Pilot wrote:
how long has it been since airports have gone from 3-to-4 letter
identifiers?

I'm not sure what you mean by this. If you mean an identifier like KABE, where
the "K" indicates a U.S. airport, I first saw that in 1989, and it had been that
way for many years. I haven't seen four-letter Ids in the States where the first
letter wasn't "K."

also, when did ATC go from 2000 feet vertical separation above FL290 to 1000
feet?

IIRC, sometime last year, but it could've been a bit earlier. The new collision
avoidance systems make closer separation standards possible.

George Patterson
Give a person a fish and you feed him for a day; teach a person to
use the Internet and he won't bother you for weeks.

In a previous article, "Retro Pilot" said:
how long has it been since airports have gone from 3-to-4 letter
identifiers?

You're confusing two types of identifiers. FAA identifiers are three
letters or letters and numbers. ICAO identifiers are four letters long,
the first letter identifies a region, and they don't allow numbers. The
continental US is the region with the identifier "K". By convention,
those airports in the continental US with ICAO identifiers just use their
FAA id with a K put on the front for their ICAO id. Most of the world
uses a more complicated system with the second letter designating a
sub-region. Hawaii, Alaska, the US Virgin Islands and other places use
"P" and a second code letter, and then the mapping between the FAA id and
the ICAO id is more complicated.

US pilots became more aware of the ICAO identifiers when the US started
using METAR and TAF weather reporting formats, the same as the rest of the
world. That happened about 10 years ago. We had to change the FAA id of
several airports to elminate numbers so that they could be given ICAO ids.
Also, GPSes use the ICAO id rather than the FAA id when the airport has an
ICAO id, just to reduce confusion between airport ids and co-located or
nearly co-located VORs with the same FAA id.

also, when did ATC go from 2000 feet vertical separation above FL290 to 1000
feet?

RVSM (Reduced Vertical Separation Minimums(?)) were phased in quite recently.
They came about because of improvements in altimeter technology, and maybe
also as a result of TCAS and mode-S.


--
Paul Tomblin http://xcski.com/blogs/pt/
please excuse my typing, but my whole left arm is in a cast. and i don't
mean _the king and i_.

"Retro Pilot" wrote in message
...

how long has it been since airports have gone from 3-to-4 letter
identifiers?


They haven't, not really. The 4-letter identifier is the ICAO identifier.
They've been in use since probably some time in the fifties. They've only
come into common domestic use in recent years because of GPS databases and
the need to distinguish airports from navaids of the same identifier. The
3-letter airport identifiers are just as valid as ever.



also, when did ATC go from 2000 feet vertical separation above FL290 to
1000 feet?


US domestic RVSM, Reduced Vertical Separation Minimums, was implemented
January 20, 2005.

"George Patterson" wrote in message
news:rOyZe.1925$%L4.26@trndny02...

I'm not sure what you mean by this. If you mean an identifier like KABE,
where the "K" indicates a U.S. airport, I first saw that in 1989, and it
had been that way for many years. I haven't seen four-letter Ids in the
States where the first letter wasn't "K."


The "K" indicates an airport in the contiguous 48 states. Alaskan ICAO
identifiers begin with PA, PF, PO, or PP, and Hawaiian ICAO identifiers
begin with PH.



IIRC, sometime last year, but it could've been a bit earlier.


A bit later, actually, January 20th 2005.



The new
collision avoidance systems make closer separation standards possible.


It's not collision avoidance systems that make RVSM possible, it's new
altitude tolerance criteria. An aircraft type has to demonstrate it can
remain within a specific altitude error tolerance. Some older aircraft types
required improvements in their autopilot and air data systems to meet the
standard, some required special attention to the skin surface in the area
surrounding the static ports.

"George Patterson" wrote in message
news:rOyZe.1925$%L4.26@trndny02...
Retro Pilot wrote:
how long has it been since airports have gone from 3-to-4 letter
identifiers?

I'm not sure what you mean by this. If you mean an identifier like KABE,
where the "K" indicates a U.S. airport, I first saw that in 1989, and it
had been that way for many years. I haven't seen four-letter Ids in the
States where the first letter wasn't "K."

also, when did ATC go from 2000 feet vertical separation above FL290 to
1000 feet?

IIRC, sometime last year, but it could've been a bit earlier. The new
collision avoidance systems make closer separation standards possible.

RVSM began this past January.

Well, here's another question, then. Where do the common identifiers used
for major commercial aiports come from? For instance, Heathrow is LHR on
baggage tags and airline systems, but I don't think it's ICAO identifier is
ELHR. Same queston for BOS, LAX, PHI, etc.

Shawn

"Retro Pilot" wrote in message
...
how long has it been since airports have gone from 3-to-4 letter
identifiers?

also, when did ATC go from 2000 feet vertical separation above FL290 to
1000 feet?

and, no, I was not doing time in prison for the past 20 years for
trafficking.

In a previous article, "ShawnD2112" said:
Well, here's another question, then. Where do the common identifiers used
for major commercial aiports come from? For instance, Heathrow is LHR on

IATA.
(International Air Travel Association, I think)

--
Paul Tomblin http://xcski.com/blogs/pt/
please excuse my typing, but my whole left arm is in a cast. and i don't
mean _the king and i_.

above FL290 seperation is now 1000 ft.

In article et,
Steven P. McNicoll wrote:
They haven't, not really. The 4-letter identifier is the ICAO identifier.
They've been in use since probably some time in the fifties. They've only
come into common domestic use in recent years because of GPS databases and
the need to distinguish airports from navaids of the same identifier. The
3-letter airport identifiers are just as valid as ever.

There are also private airports (atleast here in california) that have
4 digit's.

http://airnav.com/airport/CA20

for example.


--
Steve Rubin / AE6CH / http://www.altdb.net/
Email: / N6441C / http://www.tch.org/~ser/
"Why don't you mind your own business?" -- John Navas 01/04/05
"If you don't like it, keep it to yourself" -- John Navas 01/04/05