*Groans at Holloway's joke*
Actually, this is a pretty tough question - much harder than you'd have thought it would have been. There are several issues:
- What is the legal limit for flying in bad whether?
- What is the limit of bad weather in which it's safe to fly?
- What restrictions does your club place on you?
- What other obscure restrictions are there?
- When does it stop being fun?
All the above answers are good, and I think between them they probably cover most, if not all, of the above. I'm sure there are other things that I've forgotten, too!
Legally, there are a number of different limits, and you'll need to learn them all for your PPL exam. Broadly, though:
- There are legal restrictions on minimum visibility and minimum seperation from cloud for VFR flying in the UK. These vary, depending on what class of airspace you're in, how high you're flying, and how fast you're flying.
- As a PPL without any further ratings, your license will include a restriction to always fly in sight of the surface (i.e. you can't go above a layer of cloud unless there are holes in the cloud), and with a minimum visibility of 3km, even if the airspace you're flying in allows other pilots to fly in lower visibility.
- There are several different low-flying rules. If the cloud base is low, you won't be able to get high enough to be able to comply with the low-flying rules.
- There are other conditions where it's illegal to fly, but these aren't very relevant. For example, it's illegal to fly in known icing conditions if your aircraft isn't equipped with anti-icing or de-icing equipment. However, you probably wouldn't want to fly in most icing conditions anyway if you don't have an IMC rating.
And there are probably other rules I can't think of right now. Note that there are no restrictions about flying in rain, for example. Heavy rain will probably reduce the visibility to below the legal minimums, but plenty of people fly light aircraft through small showers regularly. It's probably not fun in an open-cockpit aircraft though!
Of course, what's legal and what's safe are not always the same. For example, very few low-time PPLs (myself included) would be happy flying any kind of distance in 3km visibility. What you're happy with will depend largely on what you're used to. If you've done all your flying in the beautiful clear post-thunderstorm air of Florida, you'll be a lot less capable of handling a misty English morning than if you've done all your flying on misty English mornings!
There are some conditions where it's never safe to fly, regardless of how much experience you have. Thunderstorms are the most obvious example - if you see thunderstorms in the forecast, and you're not confident you'll be able to steer around them, stay on the ground.
Clubs often place restrictions on minimum visibility and cloud base which are in excess of the legal minimums. For students, they'll usually be much lower if you're solo. The restrictions might be lifted once you get your PPL, or once you get a certain number of hours - ask your club what their restrictions are.
A few people have mentioned cross-wind limits. There is no legal requirement to comply with any cross-wind limit. In fact, just because an aircraft has a maximum demonstrated cross-wind, it doesn't mean it's not safe to fly in higher cross-winds. It's only a maximum
demonstrated crosswind - it might be that the test pilot couldn't find any higher winds to test the aircraft in. Having said that, you will probably find your insurance company will be unhappy if you're flying above the demonstrated limit. And it's certainly not something you want to be trying by yourself for the first time. Remember the old saying about old pilots and bold pilots.
Everything so far describes when it's legal and safe to fly. But of course there are conditions when it's legal and safe, but it's simply not fun. Moderate turbulence, for example. Or in rain. If you're only flying for fun, it simply doesn't make sense to fly in these conditions. Except that, from time to time, you might like to fly just so to make sure you've got the confidence to deal with the conditions if you encounter them unintentionally.
Well, I can't think of anything I've missed, but I'm sure someone else can! Hope that answers your questions.
FFF
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