Will a high wind flip a parked trailer?

[Kai in Seattle]

Maybe! But also maybe not.
From an article online, a mathematical way to tell:

The wind force on your RV is:
Wind force = Lenght x Height (wind resistance) x F
W=L x H x F
where F is:
20 at 90 mph
29.8 at 110 mph (I rounded to 30)
41.8 at 130 mph (I rounded to 42)

If W < Gross Trailer Weight, then you are unlikely to flip.
If W > Gross Trailer Weight, then you are likely to flip.

For example, a 30 ft RV 8 ft high (the main body sheeting only) will have a 7154 lb force pushing on it in a 110 mph wind (gust, not average). If this is more than the weight of the RV it will likely flip over.

You should have, at least, a 50% safety factor, so that RV should weigh at least 10,731 lb to be safe.


These forces go up as the square of wind speed, so a 130 mph wind will produce a 10,000 lb force. This is the worst case scenario with the wind hitting the RV square on; if the wind is at a 45 degree angle reduce the force by 30% (cosine of the angle).

I calculated Peanut's odds of being flipped.

Size: (main body) 13 x 7 feet=91 square feet of wind resistance.

At 90 mph: Wind force= 91 x 20 W=1820. Peanut weight loaded: 2150 - 2250 so we're probably safe at 90 mph.

At 110 mph: Wind force=91 x 30 W=2730 Peanut's weight: 2250 at most. Whoops! over she goes!

At 130 mph: W=91 x 42 W=3822. Peanut's weight 2250 at most. Rolling, rolling, as the winds are blowing...

Solution: hitch Peanut to the van, which weighs 6050 lbs. empty. And it won't be empty. Problem solved.

Whew! I feel a lot safer!

Now for the real danger: falling tree limbs and, apparently, large cold iguanas! But that's another calculation.

BEST
Kai

[mary and bob]

Even hitched the trailer can pivot on the ball. You can find some videos where a camper trailer flipped over but the tow vehicle stayed upright. I once saw the wind flip a pop-up camper on to it's side. That was on the Outer Banks NC, Oregon Inlet campground.

[LyleB]

I assume these calculations are assuming a squared off rig, not the eggs most of us have. Rounded corners mean a fairly substantial portion of the wind force is hitting at an oblique angle, thus with reduced force, similar to your 45 degree scenario.

[ShelbyM]

Very cool and useful info. Thanks!

[Kai in Seattle]

Hitched may not be perfect, but it's gotta help some.

The rounded eggs are much more aerodynamic than the straight...I feel better knowing it would take quite a blow before we'd need to worry about rolling over.

[Darwin Maring]

I used a more simpler way of calculating: The other day the wind turned over several cars. The wind has been known to turn over campers and tractor trailers. During a Huricane it turned over a train, engine and all in Florida Keys so calculating using the above formula my answer is "YES".

[Kai in Seattle]

Darwin-- of course you're right, sufficient wind will tip over/blow away/wreck anything, including carving mountains down.


The article said at 180 miles an hour pretty much everything will roll over. But luckily, 180 mile winds are rare! I think the tree branches would get you long before the wind would...though the wind would still be responsible.


May we all have calm skies and clear sailing!


BEST
Kai

[Glenn Baglo]

Caution. Coarse language.

https://www.youtube.com/watch?v=S7Fu-v490-c

[Kai in Seattle]

We always enjoy Ron White. Thanks for the clip.


BEST
Kai

[Bobbie Mayer]

Where do you get F for lower speed winds? This happened to my Escape in what was probably a 70 mph gust. (Didn't turn over, just moved on the driveway; it does have a front wheel on the jack.)

[Kai in Seattle]

2 at 50 mph?
11 at 70 mph?
20 at 90 mph?
30 at 110 mph?
42 at 130 mph?
54 at 150 mph?
66 at 170 mph?


Guesstimates...apparently your trailer wasn't "stuck" to the hard surface; light enough to skew but aerodynamic enough for the wind to only skew it and not push it over. Hope it wasn't damaged!


And I thought of something else...with all of us inside, Peanut weighs a lot more than 2250. Add another 496 pounds for 2 pugs and 2 people. Never mind who weighs what! Says the chief ballast.
So 2746. Our margin of safety grows with every pound I put on! I believe I'll have another nut log, Jeeves! Gotta keep the trailer with the sunny side up!


BEST
Kai

[Bobbie Mayer]

It is 15' long, 8 1/2 high (but really only 8 for the bulk of it.) Probably would take F=15 to tip it. The front wheel allowed it to move isntead. I'd gone upstairs to look across at the waves and noticed it moving down on the driveway and ran out and blocked the front wheel. (It had been blocked only from rolling forward). We do get gusts that high on occasion. It's safely at my friend's house now until I get the garage door height increased.

Interestingly, though, driving along the Oregon coast I felt less force from the wind than I do pulling the Campster. It may be that it has more rounded corners or bigger tires.

Remember you need to subtract the tongue length. So I forgot that. 12 feet long, 8 feet high, only 96, so it would take a 20 to knock it over. Campster, 10', 7' high, 70, but weighs about half as much so a 15 could have knocked it over- so it makes sense the Escape felt more stable in the wind.

[steve dunham]

Since the gray , black and fresh water tanks sit low in the trailer , would filling the tanks with water before a storm lessen the chance of tipping over ?.

[ZachO]

Those calculations make me feel a bit better about the closest I've ever felt to flipping over, which was in my old motorhome. It was pretty scary. Desert wind storm. Nothing like hurricane winds but pretty darn windy. I got sandblasted and my solar panel and some other stuff were damaged. It really felt like the wheel lifted off the ground a couple times.

But a motorhome has the stout frame of a truck, plus the engine and transmission, so knowing what I've seen from going to the dump in my current pickup, it weighs around 4,000 pounds. So I have to figure the motorhome was heavier than that, and has a lot less surface area than my current trailer, which weighs a lot less. Wouldn't want to have been in those same winds with my Bigfoot, that's for sure.

[ZachO]

Originally Posted by steve dunham

Since the gray , black and fresh water tanks sit low in the trailer , would filling the tanks with water before a storm lessen the chance of tipping over ?.

Seems like even just the weight of them at all would help by making the trailer heavier overall. But yeah, the lower the center of gravity the better. I'd have a hard time believing they wouldn't help.

[Bobbie Mayer]

One thing to remember, looking at my photo- the wind may not tip you over, but it might push you sideways to cause a lot of sway or even to make a less-aware driver veer off the road or into another lane.

[Wayne Collins]

Just like a ship at sea, If you can head into the wind, you present a smaller sail to the wind.
Do any campgrounds have tie down anchors? If so, you need some long straps to throw over the rig. Or, if you have some of those corkscrew type pegs screw them in good and attach your straps. Maybe connect them to the rear bumper and front frame.

[Kai in Seattle]

Steven,
I'd say, yes, having the low-sitting water, gray, and black tanks full would ballast it and make it safer in a wind...but then again, consider rolling over with a full black tank?


Hmmm. We don't have one, never have had, so don't know if there's a stop to prevent spillage in such an event.


BEST
Kai

[Carl V]

I've posted this before, but on the occasions when we camped in Outer Banks' Oregon Inlet CG with the popup, due to the wind, I always put some guy lines on each corner post, pinned with 24" stakes. It stopped the roof from constantly moving and shaking and made the camper much more quiet.
Now when the first big thunder cell got right over us, boy I was glad to have them!
They may not have resisted a microburst, but we've seen a few storms where the wind blew pretty hard and nothing moved, and we felt much more secure.
See the wind pushing the canvas:


Storm coming!:


Next time we head down there will be with the Trillium!

[Kai in Seattle]

Carl,


That open campsite looks almost exactly like the Pacific Beach State Park in Pacific Beach, Oregon. We stayed there for the first time last fall, after trying to get a reservation off and on for 20 years!
The guy wires are a good idea. It wouldn't be that big a deal to carry a set.


BEST
Kai