I have a full ironman scheduled in 2018 and will therefore be doing a lot of mileage next year. My question is, if I get a flat during the race, is it basically race over as it is unlikely that I or mechanic will be able to fix at roadside or is there a quick fix solution to get me to the end of the 180k race? PS - I am a female and not good at changing tyres quickly at the best of times
It is a matter of personal preference. Triathlons generally have to be self supported (with some exceptions) so getting a full wheel swap like in Pro Bike races is not an option. I run clinchers mainly for this reason as they are easier (for me) to swap out on the side of the road. However, depending on your rim/tire this can still be pretty tough sometimes.
So if you are running tubs you would have 2 options:
Carry a spare tub tire & CO2. You would need to be able to peel off the old tire, re-seat the new one, and re-inflate. This can be pretty hard. Also, usually when you glue on new tubs at home you use fresh glue and let then set awhile to make sure they are well adhered. However, in this case on the side of the road you will be re-using the old glue or you could try tube tape (never used it personally). This is a bit dangerous as now your tire is not as secure onto the rim and you risk "rolling" it off in hard cornering ...
Carry a sealant like Vittoria Pit-Stop. This might seal & re-inflate your tire but if it doesn't then you are out of luck.
Consider clincher and go with puncture resistant. In the 28 or 32 width to resist pinch flat. Not adding much weight. A benefit is you don't need to change out from training to race tires.
Most races you are not going to flat. You may go the whole season with no flat.
Practice changing flats. You may be out of contention for the win but you can still finish the race.
If you have not bought wheels and want to go tubular then that is certainly an option.
Don't cut the last 6 inches of the corner as that is where most debris is.