What is the exact format, sources, and the variables of weather
information received or collected inside an aircraft, for example,
Boeing 747, and Airbus;how frequently this data is collected or
received, and how this information is stored and processed; for
example, displayed?

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Request for Question Clarification by omnivorous-ga on 28 Feb 2003 04:20 PST

Aligh --

Is your interest in the weather updates received by the flight crew
(for destinations) or in the weather experienced by the aircraft
in-flight (winds aloft; air temperature; icing conditions; sky
conditions; turbulence reports)?

Best regards,

Omnivorous-GA

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Clarification of Question by alihg-ga on 04 Mar 2003 15:34 PST

We are interested in the weather experienced by the
aircraft in-flight (winds aloft; air temperature;
icing conditions; sky conditions; turbulence reports);
i.e., during the flight.

Alihg - -

The information gathered in commercial aircraft comes from several
sources and is communicated in several ways to group personnel. 
Information that’s important to flight deck crew and others in the
operation of commercial air service includes:
1.	winds aloft
2.	outside air temperature (OAT)
3.	icing conditions
4.	ceilings
5.	turbulence
6.	thunderstorms
7.	visibility

According to a 20-year American Airlines pilot that I talked with,
first communication of weather information is always to the FAA’s Air
Traffic Control (ATC).  ATC controllers, who monitor aircraft
positions on radar, may communicate weather information to Flight
Service Stations if their workload allows (though not much of the
verbal information makes it to weather forecasters).

Verbal communications can also be made between flight crew and the
Airline Dispatch office of each carrier, either on designated
frequencies or via a nationwide radio service called ARINC:
ARINC
http://www.arinc.com/

A system called Aircraft Communication Addressing and Reporting System
(ACARS) automatically communicates key information about a flight to
the Dispatch Office of each airline, including pushback time; takeoff
time; and landing.  Weather information can be keyed into the ACARS
system, though it’s not done very often because only recently have
ACARS units started to include a usable keypad.  The format of ACARS
information is described on this U.K. website:
ACARS
"About ACARS"
http://www.acarsonline.co.uk/aclink/alabout.htm

ACG Systems, AirNav Systems, Sundstrand and Rockwell/Collins are among
the suppliers of  ACARS systems:

AirNav Systems
http://www.airnavsystems.com/

Rockwell/Collins
"Toulouse Commercial Avionics"
http://www.rockwellcollins.fr/gb/avionics/key.htm


Each of the measurements has a different source for information,
indicated below:
1.	winds aloft: the Flight Management System (FMS) or global
positioning satellite (GPS) information
2.	outside air temperature (OAT) – OAT gauge
3.	icing conditions – visual observation
4.	ceilings – visual observation 
5.	turbulence – pilots observation
6.	thunderstorms – weather radar
7.	visibility – pilots observation

Google search strategy:
ARINC + avionics
ACARS + avionics
weather + "Boeing 747" + avionics


If this answer is not sufficiently clear, please request a
clarification before rating it.

Best regards,

Omnivorous-GA

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Request for Answer Clarification by alihg-ga on 15 Mar 2003 06:12 PST

Hi,

Thank you for your answer. However I need some clarifications.
Q-Are you saying that there is no obvious format by which the data is
collected, and that there is no onboard system that we can use to
store the data and then process it later; for example, displaying it
to passengers on the screen or using it for any other useful purpose.

regards.
Alihg

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Clarification of Answer by omnivorous-ga on 15 Mar 2003 07:15 PST

Alihg –

First, as you can tell from the answer, the systems aren’t integrated
to provide complete information.  However, the ACARS system can be
used to provide at least position and air temperature information. 
The vendors’ sites (in particular Airnav Systems) have detailed
information on data and format.

You may have seen position/altitude/outside air temperature
information in wide-body planes on international flights.  The video
display provided passengers on these flights is Rockwell-Collins
Airshow 420.  It’s an in-flight entertainment system that uses
CD-ROMs.  It has a moving map and has the ability to display safety
information at the start of the flight too.

A more complete description of the system and technical details are at
the Airshow website:
Rockwell-Collins Airshow
http://www.airshowinc.com/
http://airshowinc.com/ws_display.asp?filter=company.products 
 

Best regards,

Omnivorous-GA