"Sven" writes:

I found a list of transponder codes besides the 1200/7500/7600/7700:

1255 is for VFR aircraft engaged in fighting forest fires
1277 is for VFR aircraft engaged in search & rescue operations
4000 is reserved for VFR military aircraft on training missions
4400-4477 are reserved for aircraft operating above FL600
At no time should 7777 be used, as this is for military interception
procedures
(Source: 2003-2004 Iowa Airport Directory page 135)

Are there others?

Here are some Canadian default codes (uncontrolled, or no transponder
code yet assigned):

1400 VFR above 12,500 ft
1000 IFR in low-level airspace
2000 IFR in high-level airspace


All the best,


David