Moving around in a moving vehicle - NO WAY!

To IslandHopper: The folks in my story were not ON the truck, they were IN the truck, the doors came open when the truck rolled and they were thrown out, Seat belts would have kept them IN the truck, inside the truck's roll cage and more than likely not injured at all beyond being, in the words of the king "All Shook UP" (however not as he meant them.

And to Don: Aircraft are a special case, however if I have to go to the flying head I do use the hand rail.  3 points is good in the event of turbulance.  I'd rather not dump till I'm properly located if you know what I mean (And I'm sure you do)

Or as the joke goes

Pilot "We have reached our crusing altidute of OH MY GOD... . (Stunned silence)

I'm sorry folks, the flight attendant just brought my my in-flight cup of coffee and spilled it right in my lap, You should see hte front of my pants.

(followed by a voice from the back of the plane)  "Oh that's nothing You should see the BACK of mine"

wendycoke said:

From the cockpit, "feel free to move about the cabin but when seated keep your seat belt loosely fastened."

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Next time you fly, see if there are any deadheading crewmembers on board.  They always have their seat belt snuggly fitted and rarely leave their seat because experience has taught them "clear air turbulence" can occur at any time with no warning. 

In 42 years of flying, I have seen so many serious injuries caused by clear air turbulence, that towards the end of my career I would turn on the "seat belt" sign for any sign of bumpiness and generally leave it on until well past the event.

Don

ArdraF said:

yes we do occasionally get up and walk around when the other person is driving.  But I try to make sure my hands are someplace where I can grab something in an emergency.  If I were less agile, I might not do it.

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This is a common misconception, that you will be able to KNOW a crash or turbulence is coming and have a chance to react to it.  Almost never happens.  BOOM you're flying through the air before you know it!  Even if you did see it coming, a general guideline to use for unrestrained passengers is WEIGHT x SPEED = FORCE.  This is mostly for parents who say they can reach out and hold their child in place in the event of a crash.  So for instance, a 10-pound infant in a 30mph crash (10x30) = 300 pounds of force!!  Almost nobody can restrain that kind of weight with one arm turned sideways.    Now just think of it for us adults.  A 150-pound adult (I'm being nice here) x 40mph (nobody drives 30 anymore) = 6000 pounds of force!  No human could hold on that tight, no matter what kind of advance notice or extreme strength/agility they have.  It's just not possible.  Wear your seatbelts people, they have an extremely high success rate in saving lives.

IslandHopper said:

I wear belts, and so do my kids, but I could really care less whether the person in the next car is wearing them or not.

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Your attitude will change on this if you ever know someone who dies in a crash because they are ejected.  Or if you have a job that requires you to see adults and children (strangers) needlessly die for the same reasons.  I have both.  I'm all for personal liberties and not having the gov't control everything, but laws on this are a no-brainer.

I agree Scotty, but then as I posted, I have seen more than one person dead in a crash where proper seat belt use would have either 1: prevented the death (In some cases most all injury) or 2: Prevented the crash itself.  yes, I've seen those.

So when someone thinks about the idiot in the car next to them w/o a belt on.  I know of at least one accident where I'm 100% convinced had the at-fault drunk been wearing his seat belt the crash would not have happened.  Two people (neither the drunk) were killed in that crash.  And had he buckled up as a habit (Drinks will buckle up if it is their habit to do so) the accident would not have happened. or at least would not have happened that way and the odds are everybody would have lived.

He now has to live with the knowledge he killed two people.


For the pilot who posted about flight crews keeping their belts on.. .. I find that I'm most comfortable with the belt on as well when flying,  As I said, if I got to go,  well, then you got to go, else I'm sitting with belt on, makes it easier when the sign "Fasten Seat Belt" comes on don't you know.

Took a heilcopter ride over the city oh, around 29 years ago..... When the pilot took us out over the water I was kind of glad I had that 5-point harness on (The bird went down FAST,  Thankfully it stopped short of anything dangerous,  Actually, I know exactly why it did that (And why it will always do that)

Scottydl,

Actually, your calculations are very conservative. A 10lb. baby will exert an average force of 540lbs., and the 150lb. person comes out to 8035lbs. for a 1 foot stopping distance. If the stopping distance is reduced, like if you're thrown out of a vehicle and you head hits a large tree (and they usually don't move very much), the average force increases inversely proportional to the distance. Lets say the stopping distance is only 6 inches. The forces are now 1,080 and 16,070lbs. respectively!   

But, Carl, how do you really feel about this

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Just getting back to this thread.  Wendy, it shows Carl cares about the framily.  He just wants us to stay safe.  Who knows, maybe I'll even start being more prudent about staying seated because of what he said.    Also, when seated in an airplane my belt may be loosened for comfort, but it's always on.

ArdraF

ArdraF said:

Just getting back to this thread.  Wendy, it shows Carl cares about the framily.  He just wants us to stay safe.  Who knows, maybe I'll even start being more prudent about staying seated because of what he said.    Also, when seated in an airplane my belt may be loosened for comfort, but it's always on.

ArdraF

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Thanks Ardra.   Let me make a point.  I specified a stop from 30 mph in 50 feet.  That is a hard low speed controlled stop.   The kind you would make if a car suddenly backed into a  residential street in front of you.   It was not a crash!  It was something that is in the range of normal driving.

I was brought up using seat belts, so even if there hadn't been a seat belt rule for my son, I would still enforce it.  Life became easier once Matthew could climb into his car seat.  A couple of times, however, I have assumed my wife buckled him in while she assumed I had.  Seconds after starting the car, Matthew screams (and I mean screams), "Don't move!  I'm not buckled in!"  He was actually terrified that he wouldn't be buckled in while we were moving.  That's really cool in my book.  Sorry, just thought I'd add my own little story. 

-Dave

Karl said:

Actually, your calculations are very conservative... The forces are now 1,080 and 16,070lbs. respectively!

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I believe those increased numbers without a doubt... the WEIGHT x SPEED = FORCE ratio is a kind of generic "everymans" explanation of how serious crash forces can be.  Obviously there are many factors that increase those forces dramatically, that are not accounted for with that simple calculation.  Everyone just think of all those crash-test-dummy slow motion films you've seen in the past... even the restrained dummies seem to bounce around like crazy, not to mention the unrestrained ones.  The amazing thing is that federal safety regulations for auto manufacturers only require crash testing at 30mph... that's what you are seeing, 30 MPH!  It looks so much more serious to me.  Just imagine what happens at 45-70mph where most crashes actually occur. 

cougar3514v said:

Seconds after starting the car, Matthew screams (and I mean screams), "Don't move!  I'm not buckled in!"  He was actually terrified that he wouldn't be buckled in while we were moving.  That's really cool in my book.  Sorry, just thought I'd add my own little story. 

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Same exact thing here, Dave.  My 5-year-old son is the same way with his booster seat.  He has autism and can't really understand the safety aspect of being belted in, but he's so used to the routine of being buckled that he'll exclaim "Buckle me in!  Buckle me in!" if the car is in gear before his seatbelt latch clicks. 

scottydl said:

I believe those increased numbers without a doubt... the WEIGHT x SPEED = FORCE ratio is a kind of generic "everymans" explanation of how serious crash forces can be.  Obviously there are many factors that increase those forces dramatically, that are not accounted for with that simple calculation. 

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Actually the formula for deriviing force is MASS x ACCELERATION = FORCE. [ f = ma ]  Weight is actually the force on the mass of a body caused by gravity which has an acceleration of 32.2 ft/sec2.  Without digging into the math of the thing the numbers work out like about so:    If your motorhome is doing 60 mph (88 fps)  and comes to a halt in 10 ft. (ie crashes), a person with a mass of 150 lb. walking back to the kitchen for a cup of coffee will be subjected to a horizontal acceleration 387 ft/sec2 which is 12.1 times the acceleration of gravity.    That 12.1g acceleration will impart a force of 1815 lbs when the person hits whatever is now the front end of the motorhome. 

Splat!

Good point Carl, it is not Mass Times Speed but works out to Mass Times Speed Squared when you stop instantly (And the person will stop instantly in the case you cited)

This also figures into breaking (Stopping distance)

All wheels locked you get a kenetic force of Mass times Speed squared.  The stopping force is mass times friction times gravity Times time, When the second equals the first you have ZERO speed.

Well, as you can see mass cancles out so be it a motorcycle or a semi truck  Wheels locked, the skid distance is the same (KEY PHRASE, WHEELS LOCKED)

Now, add in a trailer or towed with out brakes and you now have

Mass(a) speed speed + Mass(b) speed speed = Mass(a) friction gravity time  It's gonna take a lot longer to stop.

Good point Carl, it is not Mass Times Speed but works out to Mass Times Speed Squared when you stop instantly (And the person will stop instantly in the case you cited)

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Actually what you cite is energy which equals  one half the mass times the square of the velocity (speed).   (E = ?MV2)    Our poor soul walking back for a cup of coffee when the motorhome executes that stop in 10 feet from 60 mph develops a energy of 0.5*150*(88)2/32.2 = 18,037 ft-lbs..  My 338 Winchester Magnum rifle, a bear gun, develops only 4,000 ft-lbs.   LIke I said....

SPLAT!

Yup. SPLAT is the word all right

And think about the jerk who was speeding up the freeway in his convertable,,, No belt, ran off the left and skidded down the median wall a ways, rolled over on his roof, coming half out of his car and draping over the windshield.

Now even in a convertable these days you are protected by a roll cage, the top bar of the roll cage is the top frame of the windshield and he was draped over this when the car rolled to upside down and continued to skid for many yards down the freeway.

Poor guy ended up with a long smear and split personality.