Unpowered cargo gliders on tow ropes promise 65% cheaper air freight

https://newatlas.com/aircraft/towed-cargo-gliders/

by tomcdonnell • 2 years ago

77 77 2 years ago

What the US needs is to fix its rail system. eminent domain the whole thing, pay off the robber barons and just run it like it matters to get shit from here to there.

schiffern• 2 years ago

  >rail

Wrong niche. This is in the same market as conventional air freight.

nvy• 2 years ago

Air freight is phenomenally inefficient compared to rail.

crote• 2 years ago

How much air freight really needs to be transferred by air, though?

Air freight makes sense when you need to get something across an ocean in less than a month, or across the continent in less than a day. If the US were to invest in running the railroads efficiently, getting a package from NYC to LA in less than 72 hours should be possible - that's fast enough for regular Amazon shipping. If you electrify the railroads you could avoid an awful lot of CO2 emissions.

There are currently already container trains running from China to Europe (or at least there used to, before Russia started a war). It's a viable midpoint between ocean freight and air freight.

sarchertech2• 2 years ago

When it comes to freight rail, the US is in the top handful of countries in the world by pretty much any metric.

We’re not great at passenger rail, but we beat all of Europe when it comes to the amount of freight shipped via rail per capita, and all of Europe except Switzerland based on the percentage of total freight transported by rail.

mitthrowaway2• 2 years ago

This is a myth oft-repeated on HN. US freight rail does cheaply transport a lot of tonnage, but it is a shadow of its former self, after a half-century of digesting the investments of the past. It's squeezed out efficiency by running longer and slower trains (that exceed the length of the rail sidings!) transporting bulk goods on predictable schedules between fixed points (like grain and coal), while slashing routes and reducing maintenance. It ships a lot of freight, but it does not do so effectively, quickly, nor safely, or flexibly.

dredmorbius2• 2 years ago

This is true, and I've made the point myself previously on HN.

But US freight tonnage is dominated by cheap bulk goods, most notoriously coal, though grain and bulk liquids (petroleum, industrial).[0]

There's also a lot of intermodal / containerised freight, but this is almost exclusively long-haul "land bridge" traffic, with very little trade or viability for short-haul freight (< 500 mi) or less-than-truckload (LTL) carriage.[1]

Cross-country carriage still takes 10--14 days, despite the fact that a through-routed train travelling at 79 MPH (peak speed on most freight lines) could in theory make the distance in about a day and a half. For time-sensitive goods, including much fresh produce, this means that truck or air freight is the only viable option.

I've gone digging for any recently published research on new innovations in traditional freight technologies and ... there simply isn't any to speak of.[2] Much of the underlying infrastructure is literally a century or more old. The last major powerplant revolution was the introduction of the diesel-electric locomotive which will have its centennial next year.[3]

Given the present obsession with electrified lorry projects, it seems to me to make far more sense to look at optimising rail-based delivery to provide for far more flexible routing, dynamic trainset assembly and disassembly, higher-speed fright,[4] integration of light freight (e.g., document and high-value product delivery) with high-speed rail systems,[5] or rail-trolly systems, in which local delivery occurs via either autonomous or small-trainset convoys which decouple from a through system and reach endpoints or local distribution centres at lower speeds on local rail or dedicated roadbed routes. Similar discussion from about a year ago here: <https://news.ycombinator.com/item?id=32967216>

______________________________

Notes:

0. Some 10 year old values by modality here: <https://news.ycombinator.com/item?id=6858737>

1. Yes, there's some of each, but in general, lorry-based over-the-road haulage dominates both markets.

2. Raised two years ago here: <https://news.ycombinator.com/item?id=32611937>

3. <https://www.borail.org/collection/cnj-no-1000/>

4. At 120 mph, cross-country transit drops to just over a day, at 25 hours. At 160 mph, 18 hours, for same-day delivery as an option.

5. At 180 mph, typical of many high-speed rail systems, delivery time from San Francisco to Los Angeles is about 2h 15m, and routes such as NYC or Denver to Chicago, Dallas to Atlanta, or Miami to Washington, D.C., or Norfolk, VA, to Boston 5--8 hours.

serf• 2 years ago

eminent domain the whole thing, pay off the robber barons

let's not frame the heaps of collateral damage that would result in as only affecting 'robber barons'.

JKCalhoun2• 2 years ago

What would that be?

Not doubting you, just can't think of collateral damage.

rrrrrrrrrrrryan• 2 years ago

We're like a couple years away from having the tech to just give all autonomous electric vehicles the leftmost lane on the interstates from 10pm-6am, then raise the speed limit to 90 or 100 mph. Let trucking companies drive these vehicles a few feet apart from each other for aerodynamics. If you could book a sleeper taxi in New York and be in Chicago in the morning, or San Francisco to Seattle, for cheaper than a flight, without destroying the environment, would you do it?

etrautmann• 2 years ago

This is roughly equivalent to flying if the car is ICE

mceachen• 2 years ago

I don't know who you've talked to about this, but just because it's electric and robo-driven doesn't mean they get to skip aerodynamic drag. Air resistance increases at the square of velocity. 4 miles/kWh at 55 becomes < 2 mi/kWh at 85. 100 mph and you're measuring in kWh/mile.

earthling8118• 2 years ago

That sounds lovely. Of course, you'll never achieve that with automobiles, so we'll be needing the trains to make it possible. No tires and significantly less chances of a collision that will kill you.

Glyptodon• 2 years ago

Just add a few more gliders and it'll be a sky train.

dreamcompiler• 2 years ago

If you go to their website you'll see several members of their senior leadership have railroad experience.

https://aerolane.com/company/

jeffbee• 2 years ago

I often advocate this position! The Union Pacific is surprisingly affordable and after you gain a controlling interest it's not as if you've just torched $80 billion, because you bought a valuable asset.

For the state of California to do a hostile takeover of the UPRR, spin off an operating company for the train part, and retain the rights of way while adjusting the attitudes of the executives, would save a large amount of money just by simplifying the High Speed Rail project. It would be well worth it and we can afford it.

monero-xmr2• 2 years ago

“Just 1 simple fix”

Hopefully they bulldoze your neighborhood first. Mine? I know my neighbors would wage war…

wenebego3• 2 years ago

Who said anything about bulldozing neighborhoods? Why would you wish that on someone else?

mc324• 2 years ago

It sounds interesting…

But it’s one thing to try and win an existential war by any means necessary including downgrading safety, but I think it’s another thing when you intend to use this for civilian freight transportation.

What’s the contingency for a snapped tow rope? Or electro/hydromechanical failure on either aircraft during take off or landing? One plane involved is plenty to handle; how do you handle two?

Light glider planes with one passenger or two is one thing, but an unpiloted freight aircraft, I’d think has greater risk. I get they might have remote operators for the glider, but some situations need proximate feedback.

JumpCrisscross3• 2 years ago

What’s the contingency for a snapped tow rope?

Same as with a dead engine: fuck off to the nearest airstrip or improvise an air strip.

bell-cot• 2 years ago

IANAAE (...not an aerospace engineer), but I smell a metric boatload of utterly delusional thinking here.

...remarkably simple way to slash air cargo costs as much as 65% – by having planes tow autonomous, cargo-carrying gliders behind them, big enough to double, or potentially triple their payload capacity.

A 65% cost reduction via tripling the payload would require that costs not increase, no? Are these huge cargo gliders free to purchase/operate/maintain? And hauling them around puts zero additional load on the engines of the air freighter that's towing them, to increase maintenance or fuel costs?

...payload-carrying gliders were towed toward combat zones in World War 2, full of troops and/or equipment, then released to attempt unpowered landings in the thick of things – with widely variable results, particularly where stone-walled farms were a factor.

True, but glider losses due to mishaps (starting with broken tow ropes) were damned high even before they got to the target area. What % of cargo being lost in transit do these folks figure is acceptable, in the modern air freight business?

These "Aerocarts" will be pulled down the runway by the lead plane just like a recreational glider. They'll lift off more or less together...

Ask anyone with a pilot's license about this. Especially if he has experience with taxiways at large & busy airports, or with taking off in anything less than picture-perfect weather, or with airplanes that lack "sporty" thrust/weight ratios.

With no propulsion systems, you save all the weight of engines, motors, fuel, ...

Even if your towing airplane magically does not need larger engines or more fuel to haul 2x or 3x the weight around - what happens when you land, and the tow plane engages its thrust reversers?

lebean• 2 years ago

I am barely smarter than a five year old and also think this is a disaster of an idea.

kelnos2• 2 years ago

A 65% cost reduction via tripling the payload would require that costs not increase, no?

I think it's a cost reduction vs. shipping that 2x (or 3x) cargo using 2 (or 3) conventional planes, not somehow making it cheaper than a single plane with its normal amount of cargo (or a magic plane with 2x the capacity).

Are these huge cargo gliders free to purchase/operate/maintain?

No, but they're presumably cheaper in those metrics than running a conventional plane. If it costs $50k to run a single conventional plane, but you can tack on one of these towed gliders and it only costs $15k more, that's cheaper than running 2 conventional planes at $100k.

And hauling them around puts zero additional load on the engines of the air freighter that's towing them, to increase maintenance or fuel costs?

Certainly this will add a cost, but if the towed glider has essentially zero fuel cost, presumably you still come out ahead. And presumably the glider will have lower maintenance costs, since it lacks engines and presumably other stuff a powered, crewed conventional cargo plane would need.

Totally agree with you on the skepticism around safety and reliability, though.

euroderf• 2 years ago

Rube Goldberg is looking down kindly upon this scheme.

bjterry2• 2 years ago

The cargo a plane can carry isn't limited only by the volume of the interior, but also by the amount of weight that can be carried safely in the plane. Airlines try to balance the amount of dense and non-dense (a.k.a. volumetric) cargo to solve for the joint constraint by charging different prices for cargo depending on the greater of its weight cost vs. its volume cost.

Even if it turned out to be practical to double the volume of cargo you could carry, it seems unlikely that it would allow you to double the weight of the cargo, since the engines and the airframe have all been designed around the same set of engineering requirements. The best case scenario would be a decrease in the cost of volumetric cargo, with dense cargo staying the same.

kelnos2• 2 years ago

The article is about having a completely separate plane (glider, really) that is towed by a conventional plane. The glider gets to ride in the powered plane's wake, and presumably the fuel cost to tow the cargo plane is less than the cost of flying two independent planes.

This isn't about making a larger conventional plane that has more volume to put cargo in.

bjterry2• 2 years ago

Right, but if a plane has a maximum takeoff weight of 600k lb, I doubt if it can safely takeoff while being 600k lb AND towing another x00k lb in a glider, which is what would be required to reduce cargo costs by 65%.

londons_explore2• 2 years ago

If you're happy for your gliders to travel at 100 mph instead of 500 mph, you can glide almost fuel free, making use of thermals and winds most of the way.

However, the finances for such a business are hard to make work since, while you save on fuel, your very expensive aircraft does fewer flights per year.

The only way to make it work would be very cheap airframes, probably without humans aboard (meaning factors of safety and maintenance costs can be dropped).

But developing new airframes is awfully hard.

nradov4• 2 years ago

Only sport gliders carrying a maximum of 2 people achieve those speeds fuel free. A large, heavy cargo glider carrying a full load is just going to crash without a tow rope, regardless of winds or thermals.

londons_explore2• 2 years ago

You probably wouldn't go totally fuel free - you'd go mostly fuel free.

And yes, the craft would have to be absolutely huge for a decent payload - and it might make sense to use different construction techniques considering that - for example an inflatable fully pressurised craft.

KingOfCoders2• 2 years ago

Reminds me of the Me 321 [0]

[0] https://en.wikipedia.org/wiki/Messerschmitt_Me_321_Gigant

Log_out_• 2 years ago

And artillery if you make the glider from gun cotton.

futileboy• 2 years ago

Couldn't you also just get fuel saving benefits from multiple aircraft flying in formation? https://ntrs.nasa.gov/api/citations/20205006743/downloads/AI...

I'm surprised that companies like fedex don't do this.

Unpowered cargo gliders on tow ropes promise 65% cheaper air freight

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