When does the U blow his whistle?

[Line_Judge]

I worked with a different crew as a LJ last week and I noticed differences when the U blew his whistle.

I very seldom hear a whistle from our U- only when a play is directly at his feet, on the try, maybe for a foul that needs to kill it at the snap.

What is standard for U's on blwing the whistle?

[tomes1978]

I'm a new U and just learning. But I hardly ever blow my wistle on a scrimage play. I did blow one Friday that was at my feet, I saw 100% that he was down and nobody else could see it. My R told me it was a good wistle. I will blow it on a kickoff of course if the returner is downed in my area. And the others like you said a deadball foul (snap infraction or false start). I'm not experienced so will also be interested in reading the responses to this thread.

[jTheUmp]

I've been U for 4 years now... you're pretty much got it right.
The other one I would add: after the play ends when you've got a foul to report (to let your WH and the rest of the crew know).

Spit our your whistle at the snap, and from then on use your voice primarily. Things like "that's it" or "he's down" or "it's over" can do a great deal to avoid any late/unnecessary hits, and lets players know that you're there and that you're watching them.

I rarely blow my whistle more then a few times a game.

[Line_Judge]

Where can u find the whistle mechanics for each position?

[HLin NC]

Page 14 of the NF Officials Manual

[BktBallRef]

I whistle if:
1- the runner is down at my feet.
2- there's a foul.
3- the wing offiicals have whistled forward progress stopped and we're trying to get the players to stop play.*

*Personally, I think too many wing officials wait to long to blow this whistle.