E L W, LM is correct; the wings are level. but inverted and the nose is above the horizon ,by the same amount it was at the bottom(lowest part) at the start of the `barrel`. If it`s not above you may end up lower and faster as you recover..
D-R; if you can maintain a constant speed around a loop,then the momentum will stay the same throughout,( if you fly an F-15/6/8,Typhoon etc). Most aircraft can`t so there is a loss of speed going up,due to gravity and Drag,mainly lift induced by pulling `G`,and then gained on the way down. If you try to maintain the `G` you will stall; ie if the stall speed is 80 kts in level flight,in a 4 G loop it is 160 kts(sq.root of load factor); practically, starting at 250 kts in a J-P,over the top ,the speed may be between 90-130 kts,but the `G` will be down to possibly less than 1,if you are trying to `shape` a vertical circle,and you will have gained about 3000 ft,depending on how hard you pull..
Now , in level flight ,starting and maintaining the same speed,the radius of turn of 1500ft,gives a bank angle of about 75-77 degrees for about 4G.
Is that good enough for a B2 ?