Yeah I agree , i thought at first i ' d like reds the most <| sep |> That one was thanks to megatroll uViolatingNDA . <| sep |> I want a partner yoga buddy so bad . <| sep |> Maybe not on the east coast . It ' s really more of a California thing . <| sep |> I believe it was that the forward sweep design had two basic problems . The first was that you needed an extremely strong forward tip to prevent warping , and the second was that it was finicky . It was more agile and performed overall better than the traditional sweep wing design , but was abanoned in the west due to a lack of expected gains compared to the RnD costs . The fact that the Su 47 didn ' t pan out into a fullfledged fighter and is being superseded by a traditional deltawinged T 50 , I ' d say the Russians agreed in the end , especially since you ' d have to throw out so much of the old aerodynamics data out and discover all the new data to replace it to make the forward sweep design to work out . It ' s sad too . I love the style of both the X 29 and the SU 47 .