bge Jump animation question

Hi I have a jump animation where from frame 1 to 15 is the crouch ie pre jump and I only want the character to get air borne from frame 15 onwards when the key is pressed, should I be looking into setting up a frame property or is using a delay the better option ?

ray -z (ground check)-
property jump = 0 ----and---------Jump=1
keypress space------/

if jump=min:1 max (endframe - 2)--------and--------add 1 to jump

jump=15---------and-------apply force

jump min:1 max(end frame)-------and----------action jump property mode jump

if Jump = endframe-1------and---------jump=0
if Ray -z(ground)-------------/

press spacebar, jump is now 1, jump gets 1 added to it, until it reaches the frame before the last frame
(so the actor holds the jump animation)

touching the ground sets jump back to zero (ready to jump again)

@BluePrintRandom thanks a lot for the help full info