Here are instructions to install them:

step 1.Copy the files you find in soldier\server\british_male_soldier in the mod folder. ( the tweak files)

And paste them here: C:\Program Files\EA Games\Battlefield Heroes\mods\tut\Objects\soldier_server\british_male_soldier

Copy the files you find in soldier\server\german_male_soldier in the mod folder. ( the tweak files)

And paste them here: C:\Program Files\EA Games\Battlefield Heroes\mods\tut\Objects\soldier_server\germanl_male_soldier

step2. Copy the sound file you find in
sound\client\West\vehicles\english\plane (wav. file) in the mod folder.

And paste them here: C:\Program Files\EA Games\Battlefield Heroes\mods\tut\sound_client\West\vehicles\english\plane

step3.Copy the folder you find in
vehicle\client (the bri_plane_pzlp11 folder) in the mod folder.

And paste them here: C:\Program Files\EA Games\Battlefield Heroes\mods\tut\objects\vehicles_client

Copy the folder you find in
vehicle\server (the bri_plane_pzlp11 folder) in the mod folder.

And paste them here: C:\Program Files\EA Games\Battlefield Heroes\mods\tut\objects\vehicles_server

Now you added the plane to your files, All you need to do now is to put the new plane on the map!

step4. let's add a plane, for example on ss.
go toC:\Program Files\EA Games\Battlefield Heroes\mods\tut\Levels\seaside_skirmish\server\GameModes\gpm_tut\16, Now open the GamePlayObjects.con in notepad.

search for bri_plane_spitfire or ger_plane_messerschmitt and replace it with bri_plane_pzlp11.
if you can't save it just drag GamePlayObjects.con to your desktop, go to setting and put of the read only. Change it, save it and replace it in your bfh folder. Start the game and enjoy your new plane.

You can also add a new plane spawner. 'more info see below)

FOR MORE INFO ABOUT ADDING THE PLANE TO THE MAP DOWNLOAD THIS TUTORIAL; http://bfhmods.ucoz.com/forum/5-9-1