Drawing of a mouth - side view - draw a straight line to see the angle/slant nose to chin; also look for negative space to get the form of the mouth.
Proko drawing tutorials
P-38 Lightning! LOVE this plane :D
F-18 Super Hornet
North American F-100 Super Sabre
Thunderbirds' F-100 Super Sabre
NASA Super Guppy...jonbeau