J-20... The New Generation Fighter III

Well bro, you are the professor, he may be onto something, but as engineer said, its customary to have a few flying prototypes in case you do find something ya don't like, for example the F-35 has a laundry list of fixes needed, buffeting at high mach and median AOA's being just one example, but in the haste to get her up and running they have gotten the cart before the horse. I point out to people that we have been developing ATF since 1986, and you can imagine the engineering hours and computer modeling not to mention that we flew two prototype of YF-22 and two of YF-23. Prototypes tend to fly a little, and fix a lot so your friend could be right. The MSFS is pretty cool, and can help you stay current, mine has an accelleration pak with the F-18 and I added a YF-23 just for fun.

On the gear down issue:

On most maiden flights I've seen, aircraft leave the gear hanging. You want to start really slowly and test one thing after the other, and not parallel.

On the J-20, we're beyond that stage, as we have seen it fly with the gear up many times. Now I'd say those passes with the gear down serve to test aircraft behaviour in the take off and landing phase.
You want to know how the aircraft handles when it comes close to min flying speed, like when an engine fails or the pilot lets speed drop out of his crosscheck. Obviously it would be foolish to fly these "approaches to stall" or actual stalls during the real take off or landing, as proximity to the ground will not leave enough room for recovery.
So you climb to a sufficient altitude, establish landing configuration and fly those maneuvers.

Thats called a spin chute, the newer fighters all fly a lot better than the old century series, spins in those tended to go flat, and once in a flat spin, where the nose comes up, and you are unable to pitch it down to break the stall, they would just spin in. So they came up with the spin chute, which when deployed was something like the feathers on an arrow, slowing the rotation and placing an upward moment arm on the tail causing the nose to drop and break the stall, so you could just fly out. Then you jettisoned the chute and went home to change your pilot diaper. LOL That was one of the plot twists in the movie top gun, where they lost an engine and the low airspeed and asymetric thrust causes a spin, from which recovery is very difficult.

Scratchman, I thought you had taken another trip, and the real reason dut, da dut, da dut, is it would be really embarrassing to scratch your shiny new airplane if the gear didn't come down. If you notice aerobatic aircraft almost always have "straight" rather than "swept" vertical stab and rudder. If you notice the F-22 it has a twin vertical tails, that if my memory serves me correctly, where increased in size in order to gain more stability in yaw at high angles of attack. Someone made the statement that we settled for the F-22 over the F-23, thats simply not true, the F-22 is a very honest "pilots airplane" . Now the Pak-Fa and the J-20 also have twin vertical stabs which are somewhat smaller, likely for more stealth, although as someone pointed out the J-20 has allflying verticle stabilators for sufficient control authority. Scratch check me on F-22 mod to the verticals?

Some pictures to share... Sorry if some have been posted before but I am just too excited...! Some might be PSed!

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Well Brat, aerobatics aircraft have different requirements I'd say. Most notably, they're far slower and have less requirement for stealth, so the aerodynamic requirements can be fullfilled almost without compromise. Plus, on aircraft with a single vert stab, it's rather strange to have that canted
For all I know the vert stabs on the F-22 are actually smaller in area than they were on the prototype (and I think you can see that looking at pictures form a similar angle), though they are further back.
If you're trying to yaw in high AoA / slow speed an all moving vert stab may be more usefull to enforce that movement, as in a conventional stab you still have that fixed controll surface part wich I imagine wants the plane to weatherwane back into the wind somewhat. I can't really say if it's better for yaw stability in other flight regimes, though.
Then again, the J-20 also has those vert fins extending down below the vert stabs, providing additional controll. So in the end, the total area might no be that much smaller than that of the Raptor's vert stab.

The YF-22 was the more agile plane I think, while the YF-23 was apparently more stealthy & faster, but also considered to be more high risk, wich is I think were the believe of "having settled for the F-22" comes from.

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Sorry for mulitple posts... I do not know why the links were all broken, but is fixed now. All images were uploaded by imageshack.us.