Yeh I know, it seemed a bit wierd ... I suppose there is just a greater chance of an accident with an aircraft around with no comms! And, crucially, it was probably just to give the fire crew something to do/training exercise ... I can't imagine they are excatly rushed off their feet

Yes, they definatley have lights there, its an Intl airport with regular 737 arrivals etc. It was just as I entered the Control Zone that it went, leaving me unable to transmit, but still could hear the other end. The guy on Radar transmited blind and said to squawk Ident if I could hear him, so I basically flew a normal approach but was just not able to confirm/read back any instructions! No biggy

I misread your post... if you could hear them, of course the light gun wouldn't be necessary. Stupid of me.

Maybe they alerted the crash crew because they know that plane well...

I am quite unimpressed with the civilian world of aviation after a year flying with the RAF in a University Air Squadron. It does all seem very cowboyish and in retrospect the standard of training is extremely low. On the other hand, things like those cracks (check the ducktape on the rear of the canopy also!) don't concern me too much, but as mentioned ... I just hope its not indicitive of the overall standard of maintanance!
That repair looks OK to me... I've seen worse!

It looks like a typical case of civvie flight schools' corner-cutting (that bubble is probably very expensive to replace)... but usually the engine, rigging, etc. is not neglected as much as glass, instruments, interior, etc.
But you never know... so remember, no matter what happens, just fly the airplane first and foremost.