Dodgy weather threatens Atlantis launch The weather forecast is not looking too bright for the launch of space shuttle Atlantis on Friday, with NASA predicting just a 30 per cent chance the venerable vehicle will get off the ground. The agency reports: "The concern is for showers and thunderstorms, flight through precipitation, and cumulus clouds." The crew of …
Florida is a particularly unfortunate choice of launchpad, for a machine whose entire exhaust plume acts like a gigantic lightning conductor with an exploding tip, don't you think? New Mexico, say, might have been more practical, but the crowds of spectators would have been smaller, and I sometimes feel the shuttle has been more about the spectacle, than what's practical.
Couple of reasons: firstly, Earth's angular velocity is greatest at the equator, giving a rocket launched in the same direction an extra kick. Florida is nearer the equator than New Mexico. Second there's lots of handy sea nearby for malfunctioning and/or exploding hardware to fall into without making a mess of any populated areas.
Of all the things that have hamstrung the Shuttle, PR considerations are among the least.
It'll be ironic if this final launch gets delayed for reasons that aren't technical: 135th time's the charm, eh?
Except a wayward rocket headed to the real Mexico at a good rate of knots in 1949, and understandably, they asked us to stop that.
Anything on the equator near a coastline is going to have crap weather, and you want to launch from the equator to the east, for orbital mechanics reasons. The best thing about KSC is that there's very little to the southeast for rocket parts to fall on, except some small islands on which you can put tracking stations. Similarly, there's nothing due south of Vandenberg except Antarctica.
Plus the conductive trail thing wasn't really known until Apollo 12, long after KSC was established.
Plus I like being able to watch rocket launches from my backyard. Pbptttbpt!
It's not a criticism of Kennedy Space Center, as such, but the fact that shuttles, specifically, are launched there (owing to their extra sensitivity to lightning risk, compared to most rockets). Weather has been one of the constant factors in delaying shuttle flights over the years. Tanking of propellant isn't even begun if there is a more than 20% chance of lightning within 5 miles of the launch pad.
White Sands is only 4° north of Canaveral, and both are more that 28° north of the equator, so the orbital velocity argument isn't that strong for Canaveral over White Sands, or some similar inland desert location.
One of the main reasons the Shuttle was less successful than promised was that turn around time between launches was much higher (meaning that there have been about a quarter, the number of flights, than were originally predicted), and reliability of launch time was much lower. Turn around times (among other things) could have been greatly helped if the things had been launched from the same site, they are often landed at, while reliability of launch envelope could have been improved by launching from a site with much less interesting weather.
However, as you say, you do get to watch them from your backyard, and who in their right minds would chose to live amidst cactus, when you can have palm trees?
Oooooo, There are many strong reasons why the Shuttle wasn't more successful. Saying that 'less missions caused the shuttle to be less successful' is a cause-effect reversal. Somehow, the planners for shuttle never anticipated the troubles with the contractor's tiles, launch costs and lower-interest in sending a 'truck' to LEO many times each year. 135 missions since April 1981 isn't bad, it is better than Soyuz manned-mission counts in the same timeframe: Soyuz T(16), Soyuz TM (34) and Soyuz TMA (21).
Saying that turn around time was _one_ of the primary factors in making the shuttle uneconomic is is not a cause and affect reversal, at all. It was a very strong contributory factor, as was stated. Turn around times were high because the launch site was hundreds of miles from the landing site, and the landing site would actually have made a better launch site.
135 launches over that time frame is pretty poor, for such a hugely expensive ship, given that the commercial sector, alone, has managed somewhere near 70-80 launches, a year, over the same timeframe. There's no way of comparing like with like, here, but 135 launches is a pretty poor record for a 'reusable' space ship.
If you want to erect a straw man, then I wish you luck in sustaining your erection, but I'm not in that picture.
What I meant by cause-effect reversal was that 'initial Shuttle successes' weren't so-good and that caused a diminished expectation for mission count. You may recall that there were quickly issues with reusing the Launch fuel tanks as well tile-robustness and burgeoning launch-costs.
My guess is that all-of-this PLUS the reduction of Soviet pressure caused its prime co-project (Reagan's Space Station 'Freedom' of 1984) to be dropped. Suddenly, the Shuttle was a space-truck with nowhere to go.
It was past-its-peak when the ISS started happening (1998+). In 1996, the shuttle was intended to operate until ~2010 with the ISS being de-orbited by 2015.
Given all of this 135 manned missions IS more aggressive than the Soviets were. They certainly logged more time in space with their Salyuts. At least two (if not three) of the five had no scientific pretenses, being totally dedicated to classified intelligence missions.
I don't really know what you were trying to do with your wiener-litany. Good luck with that.
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