In my experience, I have never come across Ada in the spaceflight domain.
Among the big players in spacecraft flight software, there seems to be a divergent east-coast/west-coast preference for C and C++, respectively. In my estimation, this is the reason: there is a wide variety of target hardware and OSes and the need for FSW to be reused across all of them (embedded linux, VxWorks, QNX on PowerPC, SPARC, intel architectures). In terms of development environments and compiler toolchains, only ISO C (and to a slightly lesser degree C++) is supported by all of them.
Edit: Various instruments on spacecraft may be programmed in Forth or other nifty languages, for example, and there's a growing effort to make some of the more "interesting" challenges in spaceflight (autonomy, fault management, guidance-and-control, etc..) to be coded in custom domain-specific languages or other scripting languages like Lua.
Among the big players in spacecraft flight software, there seems to be a divergent east-coast/west-coast preference for C and C++, respectively. In my estimation, this is the reason: there is a wide variety of target hardware and OSes and the need for FSW to be reused across all of them (embedded linux, VxWorks, QNX on PowerPC, SPARC, intel architectures). In terms of development environments and compiler toolchains, only ISO C (and to a slightly lesser degree C++) is supported by all of them.
Edit: Various instruments on spacecraft may be programmed in Forth or other nifty languages, for example, and there's a growing effort to make some of the more "interesting" challenges in spaceflight (autonomy, fault management, guidance-and-control, etc..) to be coded in custom domain-specific languages or other scripting languages like Lua.