On most airshows in UK for photos of planes taking off or landing less than 300mm will be ok (providing you would be able to get through the crowd and get nearer to the barriers), for single planes flying display - 300mm will be not enough to get nice pic without heavy cropping. On the other hand if you photograph formations then sometimes much less will do (sometimes I use 60mm ish for this).
Your other limitation when using Pentax kit will be AF speed of the camera and lens, if you get jet taking off in front of you, and you will track it with your camera trying to shot pics on the way, expect rather low number of "in focus" ones, having said that - I haven't tried K5, but I'm still not sure if there is any long lens for it that would focus quick enough (Canon users will hav no problems at this stage - saying that Canon is better than Pentax (at some bit) is not a crime here John? ).
I.e. if you look at pic no.7 in here:
https://www.pentaxuser.com/forum/topic/piotro---farnborough-24th-sat-21631

I possibly tried to take 4-5 while this F16 was taking off, on 3 occasions AF was too slow (unfortunately for a very nice closeups), but again, this was using 60-250mm which is rather slow focusing lens.

Of course there are websites on IPv6 already (existing for some time now), I would say again, why so small number of them (after so many years of "trying" to implement IPv6)? - becasue it causes so many new problems and world doesn't want it .

And of course it is a long way down the road, as I said earlier, it is so many years now when people believe IPv6 will take over and what, even with more and more realistic threat of IPv4 space depletion nothing happened yet .

What is incorrect (such a simple calculations), as I mentioned earlier, design decision made for IPv6 (and IPv4) are causing quite a significant wastage of IP space, quite similar that happen with current IPv4 years ago, just on a bigger scale now, as people were hurraoptimistic with size of IPv6, also you would have to take into account special bloks of IP space not available for direct allocations, special ones, etc, actual space available for ISPs is lower.

Hehe, another year when they announce tht IPv6 will finally get implemented on a bit wider scale, how many years this story goes on for now ? 10 or something, don't remember now.
Funny thing is that IPv6 doesn't actually sort out much of todays problems, but introduces a lot of new problems, and in fact world doesn't want it, otherwise it would be implemented by now.
I also like the way they make good PR for IPv6 by showing how big 128bits number is, of course not really understanding that in reality it is not that straightforward, and some decisions made while designin it really restrict this space significantly, apart of creating even more problems .
"users don't need to do anything special to prepare for World IPv6 Day" - well, we will see..., but their ISPs surely a lot...

Great, well done, creative, fun (and sort of tragic ) picture.

Coker, your sharpened one is slightly oversharpened, see jaggies on slants.
Here my very quick try (with my usuall, well a bit more than my usual sharpening, although I have feeling I could do it even more with this pic) using your source picture attached here.
[IMG]http://img408.imageshack.us/img408/6735/salisburycathedral003.jpg[/IMG]

More technical info presented in a clear form can be found here:
Sensorgen

Apparently it is taken from DxO (refactored).

70-400mm SSM G, seeing number of photos taken with this lens (as well as with TC added) I must say it looks good and sharp.

As other guys said, it is not true.
Pics 3 and 4 in this thread (and actuallly a lof of mine pics with 60-250 in moderate light)
piotro---farnborough-24th-sat
were taken with 60-250mm, f/5.6 at 250mm, check the bigger pics for sharpness.

Outdoor, but in a shadow between trees, hence even with bird well exposed background came out dark. Only problem was to avoid too much shake (shutter was 1/20sec), hand supported on some small fence.