Calculate fccc dp turning radius from wheelbase

[Contender]

CALCULATE DP TURNING RADIUS FROM WHEELBASE - FCCC - SINGLE REAR AXLE
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INDEPENDENT FRONT SUSPENSION - 60 degree wheel cut:
wheelbase in inches / 0.866 = turning radius in inches (eg. DSDP @ 242”WB / 0.866 = 279.445” : 279.445/12 = 23.28ft. turning radius
STRAIGHT AXLE FRONT SUSPENSION - 55 degree wheel cut
wheelbase in inches / 0.819 = turning radius in inches (242” / .819 = 295.482 :295.482/12 = 24.62ft. turning radius

will almost make it from my 22' street into my 22' driveway !!

[Rotten-Red]

If your street is 22' wide and your driveway is 22' wide and at a 90 degree angle you have all kinds of room to make the turn in. Turning radius is the amount of room needed to make a complete 180 degree u-turn.

[valentob]

Thank you Contender!

That would make the New Aire's turning radius 206/.866=237.875" or 19.82'!

[willipaul]

just make sure your front axle turning radius numbers are accurate....

what FCCC shows for specs, and what they actually are on built coaches, can be different...due to the way newmar builds the house....

[Contender]

Radius = half-circle, like turning into driveway / U-turn is full circle right?

[TonyDi]

Originally Posted by Contender

Radius = half-circle, like turning into driveway / U-turn is full circle right?

U-turn is 180 degrees. 1/2 circle. Turning into a driveway is 90 degrees 1/4 circle.

[KenSherwin]

Remember that there are several different 'turning radius' numbers to be concerned about.
1) The radius swept by the outside front corner of the body (or possibly the mirror), useful for clearing trees and other big obstacles.
2) The radius swept by the outside front tire, useful for clearing curbs and potholes outside the turn.
3) The radius swept by the inside rear wheel, useful for clearing inside curbs and small decorative rocks.
4. The radius swept by the body above the single rear axle or somewhere the rear axle and tag axle. This is useful for clearing stop signs and large decorative rocks.


Which one did you calculate and what are the others?

[willipaul]

Originally Posted by KenSherwin

Remember that there are several different 'turning radius' numbers to be concerned about.
1) The radius swept by the outside front corner of the body (or possibly the mirror), useful for clearing trees and other big obstacles.
2) The radius swept by the outside front tire, useful for clearing curbs and potholes outside the turn.
3) The radius swept by the inside rear wheel, useful for clearing inside curbs and small decorative rocks.
4. The radius swept by the body above the single rear axle or somewhere the rear axle and tag axle. This is useful for clearing stop signs and large decorative rocks.


Which one did you calculate and what are the others?

if you are clearing the stop signs and large decorative rocks, everything else takes care of it self...

[BBelanger]

I parked my rig in a parking lot. Cut the wheels all the way to the left and turned 180 degrees. I measured from the right side steer tire across the diameter where that tire stopped and got 99 feet. I actually paced it because that's what I will do to determine if I can make a turn or not. I'm not gonna run a 100 foot tape across the road.

I would swear that my FL 4018 turned much tighter than that, but I didn't measure it. In any case, this rig turns like a battleship.

[Woodman018]

Ok, I don't want to cause problems here, but, if you turn 180 degrees you will be measuring the diameter not the radius. The radius is from the center of a circle to the outside of the circle, the diameter is from outside of circle to outside of circle passing through the center. But now look at the OPs wheelbase being at 242 inches which is 20' 2'', if you could turn the front tires at 90 degrees (which you can't) and the inside rear tire simply spun (which it can't) you would need 40' 4" to make the 180 degree turn plus you have to add in more distance for the width of the coach. Then you have to add in the fact that your front tires are back from the front of the coach so that needs to be allowed for as well when it comes to missing objects. Also, you don't want to forget about the tail swing. I don't think the formula used allows for the width of the coach, front overhang or tail swing. With all that being said, the best way to really know is the large parking lot method to find out how much space is really required. My wheelbase is 250" plus a tag axle and the county road in front of my place is probably around 22' wide but my drive is narrower than that and I have no problem turning in with my toad following along. My coach has a solid front axle which I think is advertised as 55 degrees. When you allow for everything you will probably need at least 100 feet to make a u turn but turning into your drive should not be a problem.
Dave

[Rotten-Red]

Originally Posted by BBelanger

I parked my rig in a parking lot. Cut the wheels all the way to the left and turned 180 degrees. I measured from the right side steer tire across the diameter where that tire stopped and got 99 feet. I actually paced it because that's what I will do to determine if I can make a turn or not. I'm not gonna run a 100 foot tape across the road.

I would swear that my FL 4018 turned much tighter than that, but I didn't measure it. In any case, this rig turns like a battleship.

I did the exact same thing you have done with my 252" WB Spartan MM IFS chassis. I need 75' from outside of circle to outside of circle to make a u-turn. I use 3' as a pace, so I use 25 paces to see if I can make a u-turn before attempting one with the toad attached if the space is questionable. The last thing you want to do is make a u-turn with the toad and find out you don't have the room to complete the turn. Toad's don't unhook easily when put in a tight turn.

[BBelanger]

Originally Posted by Rotten-Red

I did the exact same thing you have done with my 252" WB Spartan MM IFS chassis. I need 75' from outside of circle to outside of circle to make a u-turn. I use 3' as a pace, so I use 25 paces to see if I can make a u-turn before attempting one with the toad attached if the space is questionable. The last thing you want to do is make a u-turn with the toad and find out you don't have the room to complete the turn. Toad's don't unhook easily when put in a tight turn.

Do you mean with traffic backing up and the horns beeping on a rainy day just after dark?

[Rotten-Red]

Originally Posted by BBelanger

Do you mean with traffic backing up and the horns beeping on a rainy day just after dark?

Yeah, something like that! Plus at that point you're so nervous you can't remember how to unhook it.

[Rotten-Red]

Originally Posted by Woodman018

Ok, I don't want to cause problems here, but, if you turn 180 degrees you will be measuring the diameter not the radius. The radius is from the center of a circle to the outside of the circle, the diameter is from outside of circle to outside of circle passing through the center. But now look at the OPs wheelbase being at 242 inches which is 20' 2'', if you could turn the front tires at 90 degrees (which you can't) and the inside rear tire simply spun (which it can't) you would need 40' 4" to make the 180 degree turn plus you have to add in more distance for the width of the coach. Then you have to add in the fact that your front tires are back from the front of the coach so that needs to be allowed for as well when it comes to missing objects. Also, you don't want to forget about the tail swing. I don't think the formula used allows for the width of the coach, front overhang or tail swing. With all that being said, the best way to really know is the large parking lot method to find out how much space is really required. My wheelbase is 250" plus a tag axle and the county road in front of my place is probably around 22' wide but my drive is narrower than that and I have no problem turning in with my toad following along. My coach has a solid front axle which I think is advertised as 55 degrees. When you allow for everything you will probably need at least 100 feet to make a u turn but turning into your drive should not be a problem.
Dave

My road is 20' wide and my drive is 22' wide. I can also turn my 252" WB in with toad attached. No problem.

Toad's don't really add much in the amount of space needed to make a turn. Tag axles don't add space needed also. The pivot point in a turn will always be the drive axle since it's the heaviest by far. Now if you were talking about a semi tractor with tandem drive axles where the weight is equally divided between the axles then the pivot point would be the center of the two axles.

As for extra room needed to turn with a toad. If you measure the distance from the center of your drive axle to the center of the hitch pivot point, then measure the distance from the hitch pivot point to the center of the rear axle on the toad. If the distance from the hitch pivot point to the center of the rear axle on the toad is equal to or less than the distance from the center of the drive axle to the pivot point of the hitch the toad will follow the MH without any extra needed space.