Crashes on landing are less likely to burn than taking off.
All it really is is a car with wings and some really flammable fuel.
Planes are no more likely to burn on a takeoff crash than they are on a landing crash. Yes, there is more fuel on board during takeoff, generally, but that doesn't mean they are more likely to burn. A half full fuel tank is actually more dangerous than a full one because there is more likely to be fuel/air vapor in the tank which is highly flammable and potentially explosive. However, most modern fuel systems have mechanisms to vent this kind of thing to minimize the risk. Also, all fuel systems are "crash worthy" these days. They have cut off valves, rubber, self-sealing, fuel tanks and other safety features. They can and do rupture and burn in major crashes, but it takes a whole lot of smashing for that to happen (or a system failure).
Jet fuel is technically less flammable than car gas. It's just highly filtered diesel. It has a higher flash point than car gas so is less likely to ignite from a spark than gas (petrol if you're across the pond).
Modern reciprocating engine airplanes use something very similar to car gas, but again, it's better filtered and has other additives. But it's no more flammable than car gas.
I'm no great expert on planes, but my guess is the following happens. As long as the part touching the ground keeps skidding, the plane stays upright. If the part touching the ground grabs or buries in the ground, the part causes that part to stop, while the rest of the plane wants to continue moving. Result is a flip. Speed is also a factor here, as the faster the plane is going, the more likely a snag will be to cause it to flip.
Yes. A single gear failure is dangerous because of the drag on that side and the risk of catching the wing tip causing the airplane to violently rotate and possibly start the tumbling flips. I'd much rather have a nose gear failure than a main gear failure. In practice, if you know one of your main gears is not down and locked, the pilot will opt for a belly landing (landing gear retracted) rather than try to land on one main gear and the nose gear.
A plane's center of gravity is lower than a car's with a wider area, so I think a plane is less likely to flip.
Probably not.
CG varies per aircraft just like it will per car. It depends on configuration, cargo and weight. An airplane's center of gravity is much more sensitive longitudinally than a car's because of it's center of lift vs 4 tires on the ground, but vertical CG is going to be roughly similar.
Anyway, if the pilot does not know they have a problem with a main gear, the landing can go very badly. A tumble is pretty likely in this case. The gear will probably collapse on contact with the ground and the pilot won't be ready for it. The wing on the Gulfstream is a low wing configuration with no engine pod on the wing. The wing tip will contact the ground, if it snags, the plane can potentially flip.
Hope this helps.
