If you suddenly have a problem with your Saitek X52 on your Linux Computer, Check This:
Ubuntu blacklisted a couple of devices in their recent 2.6.28-15 kernel, due to some conflicts with hardware: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/300143.
Unfortunatly this change to fix things, broke the support for the X52 
As for now the only option is to use the 2.6.28-14 kernel or older.
If you are already using the 2.6.28-15 or newer you can revert back to 2.6.28-14…
To do this go to the package manager and find ‘linux-image-2.6.28-15-generic’.
PLEASE CHECK IF YOU HAVE 2.6.28-14 INSTALLED BEFORE MAKING CHANGES.
Uncheck 2.6.28-15 and click ‘apply ‘ to apply the changes.
This will remove a couple of other packages and fall back to the previous kernel.
Now the Saitek X52 will be working again as it always did! 
Hopefully the Ubuntu People will quickly find a proper solution for this problem.
(Thanks to sothis and willbe4ce, from X-Plane.org, for their info and help)
