Simultaneous catch and momentum
 

NFHS

Team A is on their own 2 yard line 1st and 10. QB A1 throws a forward pass to A2 at the 4 yard line. It is tipped into the air by defender B2. A2 and B2 struggle for possession and have a simultaneous catch on about the 3 yard line before their combined momentum carries them into team A's end zone where the ball becomes dead and still in simultaneous possession. What call do you have and why?

If you have simultaneous possession then the ball is dead at A3. Don't have my books on me so I can't cite the rule number.

Canadian Ruling
 

CANADIAN RULING:

Team A forward progress at the A-3 yard line. 2D/9 from there.

In NFHS it is 7-5-4. Ball is dead when simultaneously caught and momentum does not enter into the equation.

So in NFHS, the ball is dead simultaneously caught even though neither player may be down? Or was this a typo?

(Excuse that fact that I do not have a NFHS rule book as I officate Canadian football.)

Not a typo. And that's no excuse. :D

RULE 7-5-4: A forward pass, legal or illegal, is complete and the ball may be
advanced when caught by any player of A or B. If a forward pass is caught simultaneously
by two opponents, the ball becomes dead and belongs to the passing
team.

7.5.4 SITUATION: Airborne A1 and B1 simultaneously gain possession of a
legal forward pass near the goal line and return to the ground where: (a) they
alight in the field of play inbounds; or (b) they alight in the end zone with the ball;
or (c) A1 lands in the end zone and B1 in the field of play inbounds; (d) B1 comes
down in the end zone and A1 lands in the field of play; or (e) A1 lands in the end
zone and B1 lands out of bounds. RULING: In (a), the ball is dead and belongs to
A at the yard line through the foremost point of the ball when A1 and B1 contacted
the ground inbounds. It is a touchdown in (b). In (c) and (d), the ball
becomes dead and the pass is complete at the yard line through the foremost
point of the ball when the players contacted the ground inbounds. If the ball has
penetrated the plane of the goal line in either (c) or (d), it is a touchdown. In (e)
incomplete pass. COMMENT: In order for there to be a simultaneous catch,
opposing players must have simultaneous joint possession, and both must be in
contact with the ground inbounds. The players’ contact with the ground does not
have to be exactly simultaneous. If A1 and B1 jointly possess a forward pass
while airborne and both land inbounds, it is a completed pass, the ball is dead at
that point and belongs to A. If there is simultaneous recovery of a fumble, the ball
becomes dead and belongs to the team which last had possession. If there is
simultaneous recovery of a free kick or scrimmage kick, the ball becomes dead
and belongs to the receiving team. (4-2-2c; 7-5-4; 8-2-1)