Though I wonder why high powered rockets are not launched at a slight angle? They could go up a few hundred feet off course, then if the parachute fails then it will land a ways away, and if the parachute goes correctly, it can drift back to where it launched.
Sometimes they are, but its fairly rare (at least up here). The reasons are pretty simple:
1) High-powered rockets are both heavy (compared to consumer-types) and can have extremely high thrust. So stabilising a pad at anything other than vertical can be a challenge. Back in my EX days I had an angled pad tip during a launch - not cool.
2) Surface winds seldom flow in the same direction as winds at altitude. as such, a "good" angle can be hard to figure out (especially when engine performance is not entierly known; often the case with experimental rockets).
3) People often shoot for max altitude; so anything other than vertical takes them away from their goals.
As for safety, its common to place the launch areas up-wind; this generally keeps things quite safe. But you do get the odd launch that goes haywire, at which point there is no "safe" place, only vigilance keeps you safe.
Bryan
---------- Post added at 04:02 PM ---------- Previous post was at 03:54 PM ----------
Has anyone ever tries a hydrogen-fueled rocket? I've thought about it, but I'm not sure how to pressurize hydrogen and an oxidizer that much... How about liquid or gaseous fueled rockets?
Liquid/gas rockets are extremely complex, and have quite complex engines. As such there is not many experimetal/hobbiest types using them. That said, hybrid rockets - gas oxidizer (usually nitrous) with a solid fuel - are becoming more common. These take advantage of the fact that its pretty easy to build a tubing/orifice system that can provide nitrous at a useful rate, while vastly simplifying rocket design by avoiding the difficulty of having to do the same for a liquid or gaseous fuel.
As for the fuel, different people use vastly different mixes. I've seen sugar-fuel like mixtures (minus the nitrates), epoxy-metal mixes, and many others. ISP's tend to be better than sugar-KNO3, but less than AN-based propellants.
Bryan