Keep close to Nature's heart. and break clear away, once in awhile, and climb a mountain or spend a week in the woods. John Muir Take a course in good water and air;
Chengdu ( Chinese cutting edge stealth technology ) Well not perfected to standards of American stealth engine heat masking technology, but certainly getting there as radar semi invisible design wise !
Experimental wing design that certainly is distinctive ,only flight tests will confirm its effectiveness in air combat , so if don't see design soon in service it will be obvious what result of air tests were achieved ( or not achieved )