Many models have had rear impact relays since the introduction of the airbag. A significant impact from either end could set you to swallowing your whistle. Perhaps if they made the airbag like a doughnut with a large hole in the center… 
… Or if what if we had collapsible whistles, that telescope like the steering column does?
I’ve also heard of homemade whistles made out of flexible plastic tubing.
Hmm. There may be a market for “safety whistles.” I wonder if any of our whistle makers will serve this niche?!
Never thought than playing the whistle could be such a dangerous hobby ! 
Here I often drive 1hour or 1hour and a half when moving around to go to meetings. I’m used to play at the stop lights and also in really big traffic jams, when the car is stopped for a couple of minutes. This is a playtime for me and I can’t imagine stopping that.
So between being for sure bored to death, or being possibly impaled to death, I will choose the second option. 
Given the choice, I’ll take “bored to death”. 
Chris, no eating apples in cars either! Remember that one? 
I often ride my bicycle instead of drive. For a while I attempted to play my whistle while riding as soon as I reached the bike path where it was straight, flat and no cars. I figured I could do that no-hands ok. The problem was breath control. I actually have to breathe more while riding my bike making it hard to play.
So now instead I sneak extra time to play by getting my lunch to go and heading over to a nearby park to play at lunchtime.
I used to be in the marching band in high school, and marched
several parades while playing clarinet or sax. Fifteen years later,
I was walking in a parade with the RenFaire and I tried to play the
whistle, and I could only get through a jig once before giving up.
I don’t know whether it was me getting out of shape or whistles
being hard to march with…
I’ve played whistle while walking on the beach. Breathing did seem more difficult than when seated, but it’s probably good lung exercise.
But whistling on a bike? Wow, that strikes me as suicidal!
lift your knees higher
O’Brien makes telescoping whistles. 
Let’s all drive to his house to test them out!