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Transmitting to Earth

Transmitting to Earth:  Map files can be inexpensively and reliably transmitted from Air Attack planes to the ground using existing standards based fire radios.

 

AFF (Automatic Flight Following) is required on all Federal wildfire aircraft.  The S-200 box from Latitude used to transmit AFF pings every 2 minutes over the Iridium satellites can also send serial data in the other minute and 59 seconds between pings.  Latitude has created a computer applet that will transmit files to a pre-defined email address.  This email address is best defined as a group email distribution list, thus allowing any number of people to receive Air Attack files simultaneously.  Transmissions over this Satellite link are extremely slow by internet standards, but does work reliably, even in the most remote areas.  Files should be just 1 or 2 KB, and the Latitude software intelligently breaks large transmissions into chunks allowing the AFF ping to always be sent as a first priority.

 

Implementation is very inexpensive, but sending data does cost.  Fire perimeters can transmit in less than a minute, while photos may take many minutes.  The S-200 has a serial port (9 pin RS232 also used for diagnostics) that needs to be connected directly to a Windows PC with a normal serial cable or USB-Serial adapter.  If the S-200 is outside the plane’s cabin, then a port or cable should be wired into the cockpit.  Older and brand new S-200s work the same, but older units will likely need upgraded firmware from Latitude. 
 
Serial ports: Computers used to always include serial ports, but now it is rare.  Simply add a USB - Serial port adapter.  

 

The Latitude Messenger applet is installed and runs on a Tablet PC attached by serial cable to an S-200.  First install the USB-Serial port adapter, and notice what serical port is assigned.  After installing Latitued Messenger, the correct serial port will need to be configured. Once installed place the Messenger in an easily accessable menu or right in the Tablet's startup directory.  Also in the Tablet'startup directory it is convenient to place the sub-directory from where files will be located for transmission.
 
For example: A Tablet PCs startup directory could contain several items for auto startup every time the Tablet boots up.
1) CloudCap ViewPoint software with fresh GIS fire map overlay
2) Latitiude Messenger (shortcut)
 
Creating a Startup directory shortctut:
Windows XP, Windows Vista and Wnidows 7 are all different in their directory structures.  Here is one method that works on all versions of Windows:
- Click/touch Start on the bottom left of the Windows destop
- Follow into All Programs, and find the Startup folder
- Right-click (hold the stylus button and touch) the Startup folder, choose Open. Let this dialogue box sit in a visible place for a moment
- Click/touch Start on the bottom left of the Windows destop
- Follow into All Programs. Find the DeLorme folder click it, and then click XMAP 7. Right-Click and hold down  (hold the stylus button, touch and hold down) on the XMAP 7 startup icon. Drag this over to the previously openned Startup Folder and drop it inside to create a shortcut.
- Be sure there is only one XMap project in the Startup directly.  Two project files will cause failure to load.
 

 

Cell phones: EVDO (Verizon) and GSM (ATT) both sell hi-speed air cards that provide very fast internet communications. When these work, they are great, fast and inexpensive.  Unfortunately they are designed for the ground in urban areas.  Signal is often lost at altitudes of more than 1000 feet or over rural areas.   When possible attach an external antenna to the card.  This might mean the installation of a new antenna on the outside of the airplane. 
 
Another possibility is a signal booster can be placed in the plane, especially if connected to an antenna outside the plane, but this is not FAA approved, and is the affect on flight instruments is unknown.   Also computers unlike cell phones, like to have continuous connections called a “session”.  When an air card jumps to a new cell towers or momentarily looses signal, it can drop the session.  Re-connection must be started over and can be slow, sometime not reconnecting before the session is again dropped. 
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