Reducing the cost of GPS databases
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Reducing the cost of GPS databases
For GPS databases (which nearly all originate from Jeppesen), there is a somewhat cunning and 100% legitimate method which relies on someone being happy to fly with data which is 1 cycle late: when you update your database cartridge, pass the previous one to another owner of the same GPS.
With the data being updated every month, the chance of a pilot flying "conventional IFR" (traditional airways IFR and traditional IAPs) discovering a problem (due to e.g. a deleted waypoint) is extremely small, would be detected when loading the flight plan, and could happen anyway because the updates may not be delivered the instant they become current. And even with a dead current database one sometimes gets unknown waypoints from ATC.
In this way, one could set up a group of pilots of which 1/2 flies on 1 cycle late data (and pays slightly less than 1/2 of the total cost, to keep it fair).
One could pass down the 1 cycle old data even further; many pilots - especially IMC Rated ones - have little need for the latest Eurocontrol airways waypoints and many pilots rarely if ever update their GPS databases anyway.
This technique works with most GPS/MFD products which lock the database download to a key stored on the data cartridge itself, so the cartridge can be passed to somebody else. It definitely works with the KLN94 (which uses a hacked CF cartridge with a unique key on it), with the KMD550 MFD (whose cartridge is not keyed and they just rely on the equipment to read/write it being too obscure and pricey) and I think it works with the Garmin GNSx30/W products (which use a proprietary flash cartridge with, AFAIK, a unique key on it).
With the data being updated every month, the chance of a pilot flying "conventional IFR" (traditional airways IFR and traditional IAPs) discovering a problem (due to e.g. a deleted waypoint) is extremely small, would be detected when loading the flight plan, and could happen anyway because the updates may not be delivered the instant they become current. And even with a dead current database one sometimes gets unknown waypoints from ATC.
In this way, one could set up a group of pilots of which 1/2 flies on 1 cycle late data (and pays slightly less than 1/2 of the total cost, to keep it fair).
One could pass down the 1 cycle old data even further; many pilots - especially IMC Rated ones - have little need for the latest Eurocontrol airways waypoints and many pilots rarely if ever update their GPS databases anyway.
This technique works with most GPS/MFD products which lock the database download to a key stored on the data cartridge itself, so the cartridge can be passed to somebody else. It definitely works with the KLN94 (which uses a hacked CF cartridge with a unique key on it), with the KMD550 MFD (whose cartridge is not keyed and they just rely on the equipment to read/write it being too obscure and pricey) and I think it works with the Garmin GNSx30/W products (which use a proprietary flash cartridge with, AFAIK, a unique key on it).
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How does the GNSx30 download process work? Do you put the card into the flash reader/writer, extract the key from it, enter it into the Garmin website, and download a database which is keyed to the key you entered? That's how Honeywell do it.
Agree re the 'current database' requirement; that is usual for BRNAV or for GPS approaches.
Agree re the 'current database' requirement; that is usual for BRNAV or for GPS approaches.
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The x30 series downloads work as follows
1 - Jepp subscription which you log onto using a Jepp Updater application
2 - Updater Application tells you how many downloads you have left for the current cycle (based on how many you have bought - eg. for a dual GPS configuration)
3 - Download the file (which I believe is encrypted) (you can download and save or download and programme directly. Once the download is confirmed your account balance (held online) is debited.
4 - Decrypt and programme the card, once this is confirmed the file is deleted.
You can program any card with your account and use it in any x30 GPS.
Only on very rare occasions does the process leave you with an invalid card and no credit to try and programme again.
I have not poked around in understanding the security of the data once it has been downloaded or understanding exactly how the system updates status to know that the file has been downloaded or that the file has been programmed.
1 - Jepp subscription which you log onto using a Jepp Updater application
2 - Updater Application tells you how many downloads you have left for the current cycle (based on how many you have bought - eg. for a dual GPS configuration)
3 - Download the file (which I believe is encrypted) (you can download and save or download and programme directly. Once the download is confirmed your account balance (held online) is debited.
4 - Decrypt and programme the card, once this is confirmed the file is deleted.
You can program any card with your account and use it in any x30 GPS.
Only on very rare occasions does the process leave you with an invalid card and no credit to try and programme again.
I have not poked around in understanding the security of the data once it has been downloaded or understanding exactly how the system updates status to know that the file has been downloaded or that the file has been programmed.
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IO I assume you are only talking IFR? Most VFR pilots I know update one a year or once every two years. PFMS (the system I use on my EFIS) is updated every 2 hours and updates are free with a yearly subscription so you can update as often as you like. You can update up to 4 devices (in practice) from one account. The file is tied to the serial number of the device.
Rod1
Rod1
