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How to Drive on Sand Without Getting Stuck (2017) (offroaddiscovery.com)
152 points by luu 34 days ago | hide | past | favorite | 74 comments

Some of this might have been covered in the article.

One thing I don't think they mention is that big off-road tires are usually a bad idea on sand. You are better off with summer tires that have very little tread. Tread doesn't do anything for traction and just makes you bury your tires faster.

Having lots of clearance is important. The second you bottom out you are screwed.

These two things can also go against each other, so it's a balance. If you have a truck with good clearance already go with the road tires.

It's not a good idea to go on sand with a vehicle that has electronic stability control or any type of breaking based traction control. You will burn the hell out of your breaks on sand. You really need 4WD with locking differentials. This is true in general for off-roading.

You can get out of a partial bury by rocking the vehicle backwards and forwards. Add some gas to rock a little bit without spinning the tires, release and let the vehicle rock back the other way, on the return swing add a little more gas, keep building the momentum until you get out.

Learn to feel for tire spins. Once you start to feel a spin get off the gas immediately. I can't describe how it feels, but you can get a sense for it.

Source: Grew up driving and camping on the beaches of New England.

Anecdotally, I was out at the beach a couple years ago for 4th of July. This brings out every huge truck in the area. Half the fun is watching them all get stuck.

At one point, there were about 5-6 huge bro-dozer trucks stuck out in this super soft sandy area. Some guy with a lowered 4wd Tahoe on some big chrome rims with super wide, low profile street tires decides to drive into that same area. His truck just floated over the sand, right past all these guys with their expensive mud terrain tires. After he drove through and embarrassed everybody else, he turned around and drove through again, then stopped in the sand multiple times, and kept going.

It was very satisfying to watch. But really kinda proved that the big blocky tires, aren't the best for sand. And a lift kit won't do anything if your tires just dig themselves in.

> Tread doesn't do anything for traction and just makes you bury your tires faster.

Large textured tread is primarily about mud. When the size of the "lug" is large enough, it ejects the mud up & back, leaving the tread free to grip again. Without these, in the mud your tires become big smooth balloons with no grip.

Big tires are primarily about climbing obstacles. Loose sand rarely is a tall obstacle ;-)

One advantage large tires can have in the sand is that when you air them down, the surface area gets much larger, and that can keep you "afloat" on top of the sand better.

Specifically, I was talking about large tree on sand there, but I wasn't very clear about that with how I wrote it.

I actually understood that -- I just wanted to point out that large tread pattern is not just a "cool look".

This sounds like what I would recommend for winter driving as well (other than the braking, the electronics do a good job in the snow).

It's similar to winter driving in some ways, but different in others. For example, you don't have to worry about burrying your wheels in winter driving and tread can make a big difference; summer tires are awful in snow. I drove a car with bald tires once in the snow and it terrifying trying to go up or down hills.

I hear letting the air out of your tires can help increase surface area

If you have rugged off-road tires and you sort of know what you're doing (know how low you can go, can measure PSI, etc): yes.

If you have factory highway tires in your average passenger car, beware, you're pretty likely to tear a sidewall.

Highway tires are fine to lower the pressure on.

All tires are fine to lower the pressure on, to a point where the sidewalls don't yet start bending and twisting.

Factory (= cheap) highway tires have weak sidewalls, so if you drop PSI too low they'll tear the sidewall pretty easily, or slip off the wheel. Off-road tires have stronger sidewalls.

Many American car owners have never even put on a spare tire. Telling that crowd to start lowering their tire pressure is a recipe for damaged tires.

I would not recommend someone who can't change a tire drive on sand. Most of the time you are going to be driving a truck if you want to go on sand, which will have truck highway tires and can handle lower pressures just fine. We regularly run down at 17-18psi with standard truck highway tires when on sand.

On this topic I highly recommend the book "Libyan Sands: Travel in a Dead World" by Ralph Bagnold, an account from a British officer who led some of the first deep Sahara expeditions with Model Ts! Lots of great stories of getting in and out of trouble, and lots of digging out cars from dunes. Bagnold later led the Long Range Desert Group in the second world war.

-Oh, and anything by desert aficionado extraordinaire Tom Sheppard. (Though being the diligent chap he is, his books mostly focus on getting out of trouble, figuring most people know all too well how to get into it in the first place!)

Can we also get a guide on how to drive on a bike trail on a steep mountain without getting stuck?


Wow. That's a good way to end up as a missing skeleton in the middle of nowhere like the unfortunate "Death Valley Germans" that were discussed a few months ago: https://news.ycombinator.com/item?id=23582417

how to drive on a bike trail

Hint: don't.

Stay at home and do donuts in your Walmart parking lot instead. People like you created it. Enjoy it.

Some nice insights! I learned motorcycling on sand (and through rivers!) while crossing Mongolia, west-to-east. Key takeaways:

- recon on foot if uncertain (this is also in the article)

- always keep a positive torque on the rear wheel and let the front wheel find its way

- don't get scared, the front wheel is supposed to skid a little and the rear wheel is supposed to slip a little

Adding a few points from my own experience:

- Keep the front wheel as light as possible, that means pushing your body far back whilst standing on the pegs.

- If things start to get twitchy give it some gas - throttle heals most such situations, though is counter-intuitive and scary.

Sand needs skinny and big (radius) front wheel, that's why most offroad motorcycles have 21" front wheel. The counter point to this is harder turning in the twisties on tarmac due to increased gyroscopic effect of bigger radius wheel. Sportsbikes have 17" for this reason, tourist and soft-enduro bikes try to strike a balance with 19" wheel and hard enduros are all 21". Bigger wheel climbs up, smaller wheel digs itself in.

>> - If things start to get twitchy give it some gas

I think the exact phrase is:

"when in doubt, gas it out"

>"when in doubt, gas it out"

Worked great for Jeremy Felts...

(but yeah, it's good advice most of the time)

Who is Jeremy Felts?

Google him.

He ran over some lady at a major Jeep event a couple years ago because he throttled out when he shouldn't have (among other bad decisions that were prerequisites of that outcome) and it was all caught on video. This would have been fine, shit happens, it's a dangerous sport. But he then tried to blame everyone but himself for it which got him a substantial amount of ridicule.

> make it to coastal regions and hit the beach

just don't. beaches are for turtle nests.

In most developed countries driving on the beach is illegal, except for specific areas.

This is true, but your statement makes it sound like it's unusual. In the USA there are a lot of beaches you can drive on. When there are endangered species they usually block it for certain location or certain times of year. For example, in New England you can't drive on the beach in the summer, but you can all other seasons. All other times they have it roped of to protect the piping plover nests. In Florida you can almost all year round.

I'm about 5km inland and it's still hella sandy. No turtles for a while.

they mark a lot of the turtle nests in Florida.... also don't cut down trees on your new lot, they are for birds even if you would like to build a home... also don't boat, you might hurt the manatees.

Yeah, turtles are on every beach on the planet /s

You'd be surprised: https://en.wikipedia.org/wiki/Sea_turtle#Distribution_and_ha...

Also, many deserts are very fragile ecosystems: https://en.wikipedia.org/wiki/Biological_soil_crust (of course there are deserts which are so inhospitable that there is virtually no life to be found, like the sand dunes in the Arabian deserts - there, offroad driving may be ok)

Your probably right, though we can argue the wider point still stands:

Beaches are populated by all sorts of life, some of which probably needs protecting.

Choose your recreation spots carefully.

Enlighten me if I'm mistaken, but are there recreation spots that are not harmful to some animal life or the ecosystem? I suppose there are forms of recreation that cause less harm than others, but if you enjoy offroad driving, you're going to hurt something. Pretty much all the things I enjoy are unsustainable and generally harmful for the environment(motorsports, winter sports, eating meat) and at some point it becomes hard to care. I fear that there is no way to keep my conscience clear if I do not live in denial. I wonder how common this is.

> Choose your recreation spots carefully.

I probably meant something like: stick to the designated areas, and if you're going to trailblazer just be aware of what to avoid to at least try to minimise impact.

Fair enough. It's possible to minimize harm by making good choices, and being good isn't an all or nothing game.

Skydiving perhaps

Includes airplanes, which I hear have a terrible carbon footprint.

I guess if you optimize for avoiding a specific form of harm you can succeed. But if you want to avoid all harm it seems a very narrow tightrope.

Ah yes, the sport with the largest carbon footprint per minute of practice.

yes, but if enough people tried it without the parachute, ...

BASE jumping for the win.

This doesn't feel like sarcasm for some reason.

Modelling tyres on (even solid surfaces) is a surprisingly tricky affair, highly recommend reading into it if you like engineering and have no friends like me

Modeling vehicle dynamics as a whole is a great subject, because there are so many parts where you have to explicitly decide on how much you wish to simulate. Brakes, tires, suspension, vibration transfer... On one hand you can have a simulated vehicle in 2 hours of coding, and on the other you can spend two months on tires alone.

One related story I like is how Assetto Corsa Competizione devs bumped into "weird" behavior emerging from their simulations which seemed like a bug - but then confronted with the actual manufacturers and found out that it happens in real life as well:


Highly recommended, video is titled "A traction control bug that was a realistic feature".

EDIT: And this is before you get to aerodynamics, which is a whole different can of worms. With todays GT3 cars, how you simulate the front splitter and rear diffuser can make or break the accuracy of the simulation. It's fantastic stuff. Wish I worked on this day-to-day. On the other hand I have trouble putting it down and going to bed when doing it as a hobby, so...

This was posted on the Cherokee XJ reddit recently showing the difference suspension design and tuning can make:



This is really showing the difference between 5,000 in suspension upgrades and over 250,000 in suspension components.

The XJ sub is where all the people who have any experience off roading go after they've been driven off all the 4x4 subs.

Have you thought about trying to get a job with a race team?

I know multiple engineering folks in the industry and they constantly tell me about how much the culture sucks. Very cool problems, but it's very cutthroat as you would expect.

Source: live near many teams just outside of Charlotte

This sounds like an opportunity to work with a lower tier race team to build reputation. Cool thing about racing, to the limit of the rules, the sport as a whole is receptive to the advance of technology if it confers a competitive advantage.

Boy, have I!

Acting on it, though... :-)

Life seems balanced now, I get to scratch my itches, not unhappy at my current job, and I don't feel like I'm saying "no" and making excuses. A tiny step here, a tiny step there, worst case it turns out to be a pleasant stroll.

Huh, weird, the car starts moving backwards at ~2:05 very slowly without the wheels moving

Very interesting video of Brian Beckman talking through some of the differences between airplane simulators and racing (car) simulators and why tires are harder:


Do you model vertical solid surfaces? https://www.youtube.com/watch?v=zsQ7kjr8C9w

Where there's a slip (ratio) there's a way

The most important point here is airing down. You should be at 15 psi for soft sand otherwise you’re going to get stuck.

I’ve gotten multiple vehicles unstuck just by letting them use my deflator.

"There is Nothing Quite Like Driving on Sand" Except maybe snow? A lot of these suggestions are things I know work in snow.

Or mud ... the tips seems generall.

If they weren't all entry level and highly general they'd be for a niche audience and wouldn't make the front page of HN.

Black ice is quite the experience too, losing all friction between you and the road is quite alarming and anything done "intuitively" will likely result in a crash.

This is a good summary and I agree with the vast majority of it, with the exception of >"Beware of “wet sand”. These areas can seem bottomless and usually require assistance" sentence.

I'm no expert but I do drive on UK beaches at least once a week to launch and recover lifeboats, and I've always found wet sand to be firmer and much better for driving on that the dry, light fluffy stuff found at the top of the beach near the dunes!

Wet sand, mud, muskeg... the danger comes from them going liquid like oobleck [1].

I didn't see the event, but helped dig out a bulldozer that had been eaten by someones pasture once. To all appearances this little clearing in the valley was firm dirt with a stream running around the edge, but when the heavy equipment climbed up onto the "puck" you could see the water squeze out of the edges all the way around. The 'dozer had got about 20 yards out before the ground cracked and went fluid under it, it sank to the roof and didn't even disturb the greenery 6ft away. Guy driving it said the whole thing took seconds, just enough time for him to jump down.

[1] https://en.wikipedia.org/wiki/Oobleck

Sounds like Leda clay. The stuff can liquify under loading. Houses and barns can get carried away.

Not 100% sure but with "wet sand" the author probably doesn't mean beach sand which just got moist from the sea, but rather so-called "quicksand" (https://en.wikipedia.org/wiki/Quicksand)

Once I got stuck in dry river sand in Arizona (had a job surveying). The truck just sank down in the sand and couldn't get any traction.

It was late in the evening on Friday, almost dark and I was out of phone range. I was single at the time, my bosses and co-workers had all gone home for the weekend and no one was going to miss I was gone until at least Monday morning.

It was probably a good 8 or 10 mile hike minimum back to the road so I decided to settle in for the night and hike out in the morning and get help. So I slept in the truck.

During the night it rained and wet the sand and the next morning I drove right out. Then I kicked myself because there was water right there in the stream and I could have wet the sand myself!

If that's an occupational hazard, buy a winch and a sand anchor.

I don't really consider myself a 4wd-er (don't even own a car right now), but i couldn't help but pop in and mention one of my favourite spots, Fraser Island, the largest sand island in the world.

Yes, every year or so a tourist group kills themselves, and yes, it's probably not an option for most of you right now with covid, but man, driving and camping on it can be an awful lot of fun.

I wish I've read this before hitting the beach! Got bogged on the sand once because I've made a sharp turn and hit the gas once I've lost traction. Had to dig the wheels out and use some coconut tree leaves to make a ramp. Locked diffs, and backed up. Got out of it without further assistance, luckly.

Reminds me, one of the toughest stage rallies in the US is Sandblast Rally. http://www.sandblastrally.com/

They always need volunteers, and you get free lunch and dinner. Great community too.

Same rules for snow.

Try to pick a speed you can maintain, stopping and starting are hard, always try to stay a little bit in motion. Minimize steering input, be smooth with the inputs you need to do. When in doubt, give it some power.

And, what to do if you get stuck: https://youtube.com/watch?v=_9mmajFmVcc

I found that video from matt's off road recovery

I hope this story summons Dan Grec, he probably has an interesting anecdote about driving in sand from his travels around Africa (ref: theroadchoseme.com)

If you ever make it to Dubai, or any place with sand dunes, go dune bashing as a passenger in someone’s 4x4. It’s fun :)

Yeah. Though that's generally done by someone who knows what they're doing, in a group of several vehicles (so if one gets in trouble they can help each other out).

man they sure make this sound a little too fun...

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