Codeshares allow me to build longer routings (which mean I earn more miles) for the same (or near the same) fare.

I know this is the UA board, but let me use a Northwest example. I can fly ANC-MSP nonstop on Northwest OR utilize the NW/AS codeshare system and fly ANC-SEA on AS and then SEA-MSP on NW using only a NW ticket and paying the same fare.

So there's one example of a benefit!

For Channel 9 fans, here's some good information about radio callsigns.

General aviation aircraft

These aircraft include private aircraft, or belonging to a large corporation. At first, the callsign is the entire registration code (e.g. N234S for a aircraft registered in the USA) for the first transmission. After a couple of transmissions, the last two or three characters can be used. Sometimes the callsign is the aircraft's model followed by the last two or three characters of the registration code
Private Cessna Citation, registry N1451W:
"November One Four Five One Whisky"
"Citation Five One Whisky"

Private Raytheon King Air, registry N18769:
"November One Eight Seven Six Niner"
"King Air Seven Six Niner"

Private Cessna 411, registry C-FFTG:
"Charlie Foxtrot Foxtrot Tango Golf"
"Twin Cessna (Foxtrot) Tango Golf"

Private Boeing 707, registry N2811S:
"November Two Eight One One Sierra"
"(November) Eleven Sierra"

Private Mitsubishi MU-2, registry JA8845:
"Juliet Alpha Eight Eight Four Five"
"Mitsubishi Eight Four Five"

Commercial aircraft

The flight number is used as reference, preceeded by what is called the airline's callsign, and followed by the word "Heavy" if it is an aircraft capable of generating a large amount of wake turbulence (see the glossary). Once the identification is done, after a couple of transmissions, the word "Heavy" can be left out, and for expedited communications, the airline's callsign can be omited.

Air Canada flight ACA404, an Airbus A340:
"Air Canada Four Oh Four Heavy"

Air France flight AFR1561, an Airbus A320:
"Air France Fifteen Sixty-One"

British Airways flight BAW592, a Boeing 747-400:
"Speedbird Five Ninety-Two Heavy"

Singapore Airlines flight SIA333, a Boeing 777-300:
"Singapore Triple Tree (Heavy)"
(Singapore Airlines operates only heavy aircraft on its passenger flights)

Military aircraft

Among the most important military callsigns, there is of course "Air Force One", which identifies any aircraft carrying the President of the United States. In the case of a helicopter, it becomes "Marine One". Other presidential callsigns include "Air Force Two" for the Vice President, and "Executive Foxtrot One" for the First Lady.

In many countries, military aircraft use "tactical callsigns" which differ depending on the mission, followed by a series of numbers. Some other examples include: "Liberty 24", "Voter 51", "Kasey 15", "Top Gun 71", "Jolly 31", "Navy Rescue 18".

Aircraft in the Force's passenger fleet (used, for example, for flying in VIPs or diplomats) often bear civilian-type callsigns. For example, in the Canadian Forces, it could be "Canforce 814".

Priority handling

The usage of the callsign prefix "Lifeguard" indicates a priority status of the aircraft in what could be called a life-or-death mission, i.e. transportation of time-sensitive cargo (such as organs for transplants) or medical emergencies. Example: "Lifeguard TWA 800 Heavy" (The ill-fated flight 800 plane did bear the "Lifeguard" prefix).

Medical voluntary flights that require some kind of priority status (however not as high as "Lifeguard") use another special callsign. The Air Care Alliance and the FAA defined "Compassion" as the callsign prefix to be used for such flights, followed by the last three characters of the aircraft's registry. N1234X would become "Compassion 34 X-ray" and would be displayed as CMF34X on flight plans and radar scopes.

If you want even more information, check out:http://www.geocities.com/CapeCanaveral/3819/COMM.HTM or http://www.airodyssey.net/reference/radiocomm.html



[This message has been edited by eastwest (edited 02-02-2002).]