Berlin Airlift, IFR

On Feb 11, 9:35 pm, John Godwin wrote:
Sam Spade wrote in news:l1Qzh.11876$c%2.1737
@newsfe12.phx:



It wasn't PAR?

In those days, it was GCA

--


Please explain the difference between GCA and PAR.......


John Hairell )
former GCA/PAR controller

wrote:

On Feb 11, 9:35 pm, John Godwin wrote:

Sam Spade wrote in news:l1Qzh.11876$c%2.1737
:




It wasn't PAR?

In those days, it was GCA

--



Please explain the difference between GCA and PAR.......


John Hairell )
former GCA/PAR controller


In the days of the Berlin Airlift GCA was what we call PAR today. The
term PAR did not exist then. Today GCA means both PAR and ASR approach
procedures.

"Sam Spade" wrote in message
...

In the days of the Berlin Airlift GCA was what we call PAR today. The
term PAR did not exist then. Today GCA means both PAR and ASR approach
procedures.


The term PAR predates the Berlin Airlift by almost a year.

After WWII there was quite a battle over which precision landing system
would become the standard.

The CAA and airlines favored ILS. The CAA had been developing the system
for nearly 20 years. From the CAA's perspective ILS was cheaper, GCA
required personnel to operate and personnel cost money. The airlines
favored ILS because it kept control in the cockpit.

The Navy and AOPA favored GCA. GCA didn't require any additional equipment
in the aircraft and ILS did, equipment which at that time wouldn't even fit
in most private or carrier aircraft.

The Air Force saw ILS and GCA as complementary systems, not competitive, and
felt both should be adopted.

GCA was composed of three radars. A search radar to locate aircraft in the
vicinity and direct them to the approach path and a set of two precision
radars, one that provided azimuth data and the other provided elevation
information.

In July 1947 the CAA administrator announced that it had been decided to
separate the GCA's radars into two types on the argument that ground
controlled approach was a method, not a system. The search radar was called
Airport Surveillance Radar (ASR), while the two precision radars were
together called Precision Approach Radar (PAR). This compromise solution
allowed the CAA to purchase the search radar without the approach radar,
protecting ILS while getting the benefits of traffic control radar.

" wrote in message
oups.com...
On Feb 11, 9:35 pm, John Godwin wrote:
Sam Spade wrote in news:l1Qzh.11876$c%2.1737
@newsfe12.phx:



It wasn't PAR?

In those days, it was GCA

--


Please explain the difference between GCA and PAR.......


PAR is part of the GCA

http://en.wikipedia.org/wiki/Precision_Approach_Radar

http://en.wikipedia.org/wiki/Ground-Controlled_Approach

I worked as a Radio Repairman at Williams AFB in the late 70's . Our GCA
was located beside the Control tower. It had 2 PAR Positions and three ASR
positions. It does not actually control airspace it only provides guidance
for landing. If a GCA like the one at Williams was to control airspace it
would not be a GCA it would be a RAPCON (Runway APproach CONtrol)

A brief note on ASR approaches. ASR does not determine Altitude
information. That is coming from the Aircrafts altimeter through the
aircraft transponder and the decoded by the radars IFF reciever which then
places that information on the Controllors ASR scope. Most of you already
know this but I though I'd add it for those who don't




John Hairell )
former GCA/PAR controller

leadfoot wrote
If a GCA like the one at Williams was
to control airspace it would not be a GCA
it would be a RAPCON (Runway APproach CONtrol)

Hmmmmm... I always thought that was RADAR Aproach
Control. Wikipedia seems to agree.

Bob Moore
ATP CFII
PanAm (retired)

"Bob Moore" wrote in message
46.128...
leadfoot wrote
If a GCA like the one at Williams was
to control airspace it would not be a GCA
it would be a RAPCON (Runway APproach CONtrol)

Hmmmmm... I always thought that was RADAR Aproach
Control. Wikipedia seems to agree.

It's been a long while (26 years) since I worked in a radar room. They use
to be in a deployable trailer out in the middle of the runways when I was
in the Air Force, which may be why I was a little off. I got everything
else right didn't I? ;-)





Bob Moore
ATP CFII
PanAm (retired)

leadfoot wrote:
If a GCA like the one at Williams was to control airspace it
would not be a GCA it would be a RAPCON (Runway APproach CONtrol)

Military approach controls are called RAPCON's. It stands for radar
approach control. Not runway because it will serve a wide area like a
TRACON.

On Feb 13, 10:14 am, Newps wrote:
leadfoot wrote:

If a GCA like the one at Williams was to control airspace it

would not be a GCA it would be a RAPCON (Runway APproach CONtrol)

Military approach controls are called RAPCON's. It stands for radar
approach control. Not runway because it will serve a wide area like a
TRACON.


What are ARACs?

John Hairell

On 02/13/07 08:52, wrote:
On Feb 13, 10:14 am, Newps wrote:
leadfoot wrote:

If a GCA like the one at Williams was to control airspace it

would not be a GCA it would be a RAPCON (Runway APproach CONtrol)

Military approach controls are called RAPCON's. It stands for radar
approach control. Not runway because it will serve a wide area like a
TRACON.


What are ARACs?

John Hairell



http://acronyms.thefreedictionary.com/ARAC

"leadfoot" wrote in message
...

" wrote in message
oups.com...
On Feb 11, 9:35 pm, John Godwin wrote:
Sam Spade wrote in news:l1Qzh.11876$c%2.1737
@newsfe12.phx:



It wasn't PAR?

In those days, it was GCA

--


Please explain the difference between GCA and PAR.......


PAR is part of the GCA

http://en.wikipedia.org/wiki/Precision_Approach_Radar

http://en.wikipedia.org/wiki/Ground-Controlled_Approach

I worked as a Radio Repairman at Williams AFB in the late 70's . Our GCA
was located beside the Control tower. It had 2 PAR Positions and three
ASR positions. It does not actually control airspace it only provides
guidance for landing. If a GCA like the one at Williams was to control
airspace it would not be a GCA it would be a RAPCON (Runway APproach
CONtrol)

A brief note on ASR approaches. ASR does not determine Altitude
information. That is coming from the Aircrafts altimeter through the
aircraft transponder and the decoded by the radars IFF reciever which then
places that information on the Controllors ASR scope. Most of you already
know this but I though I'd add it for those who don't




John Hairell )
former GCA/PAR controller


As others have noted back in the Berlin Airlift days GCA was the term used
to describe what we now call PAR. At the time if the equipment and
personnel were available for ASR approaches then odds are PAR was also
available. Probably not much demand for ASR-only approaches so calling a
PAR a GCA didn't cause any problems.

It wasn't until around the mid-70s or so that there was a real push to use
the terms "PAR" or "ASR" and stop using the term "GCA" which could be
either.

Today "GCA" is the name given to any terminal radar ATC facility that
doesn't provide approach control services.

-Some GCAs are temporarily or permanently delegated a portion of the parent
approach control's airspace to run the radar pattern(s)
-Some provide only final control service and are technically RFCs (Radar
Final Control)
-The one at Randolph AFB used to only provide radar monitoring of ILSs and
was technically a RMF (Radar Monitor Facility)

All three answer to the name of "GCA"

Only USAF approach controls are called RAPCONs. The Navy calls them RATCFs,
the Army uses the term ARAC; and the FAA TRACON. No good reason for any of
it; people just like to be different :-/