Cheat 
In the Ultima 9 directory there is a file called default.kmp. 
When opened in a standard wordpad or other text editor
you will find the following text line: 

[Cheat Commands] 

Simply add the following lines underneath it: 

alt+shift+i = toggle_avatar_invulnerable 
alt+shift+l = toggle_avatar_fly 

During game play the corresponding keys (alt+shift+i & 
alt+shift+l) will activate the cheat functions. 

You may also bind the following codes just as you did
the ones above: 

pass_one_hour 
unpass_one_hour 
sunrise_sunset 
pass_one_minute 
unpass_one_minute 
toggle_sun 
toggle_wind 
toggle_storms 
toggle_avatar_fast