The ‘Caspian Sea Monster’ rises from the grave(cnn.com)
cnn.com
The ‘Caspian Sea Monster’ rises from the grave
https://www.cnn.com/travel/article/caspian-sea-monster-ekranoplan/index.html
62 comments
Every time I read about these (rather cool) devices, I wonder how they would fare in rough seas.
As any sailor will tell you, it is seldom as smooth as the water that you always see in photos of these birds under flight.
It's like tourism photos of Ireland, where green fields are always under clear skies.
As any sailor will tell you, it is seldom as smooth as the water that you always see in photos of these birds under flight.
It's like tourism photos of Ireland, where green fields are always under clear skies.
I'm curious why the bay area doesn't have an ekranoplan ferry service. One could imagine longer routes like okl-mtv or okl-rwc or even okl-sjc becoming reasonable. Would it just be a regulatory mess?
Probably because it would take a lot of work, money, and time to validate the ferries, and someone would also have to make them; which would entail its own set of regulatory hurdles.
A more reasonable approach might be hovercraft ferries, like they have in Dover, UK. At least the equipment already exists.
A more reasonable approach might be hovercraft ferries, like they have in Dover, UK. At least the equipment already exists.
That's why it's the Caspian Sea Monster and not the North Sea Monster. They don't work that well in rough seas.
Think of these vehicles as floating on a layer of "thick air" above the ocean. They bounce through that air like a boat on the waves. If the layer is rough enough they will bounce more deeply into it the same way a boat will sink the bow deeper into large waves. If the sea is rough enough they go through the ground effect layer and hit the wave below. Bouncing off the waves without crashing necessitates a reduction in speed that kind of makes these vehicles useless compared to boats.
Think of these vehicles as floating on a layer of "thick air" above the ocean. They bounce through that air like a boat on the waves. If the layer is rough enough they will bounce more deeply into it the same way a boat will sink the bow deeper into large waves. If the sea is rough enough they go through the ground effect layer and hit the wave below. Bouncing off the waves without crashing necessitates a reduction in speed that kind of makes these vehicles useless compared to boats.
They said it could “fly” in up to 2 meters. I would’ve expected any size wave could topple it.
Caspian sea monster had a static ceiling around 3000m. Just enough for a rebase to Mediterranean Sea.
Others like the orlyonok were able to fly way higher, at an efficiency cost.
A big issue they all share, with all other seaplanes, is that taking off in rough seas is terrible, and very stressful on both passengers and superstructures.
A big issue they all share, with all other seaplanes, is that taking off in rough seas is terrible, and very stressful on both passengers and superstructures.
Badly, because uneven distance between body and surface will make it more and more unstable. It can't even turn banking properly like a plane, because outside wing will be higher from surface than inner wing. It had to make turns of gigantic radius staying horizontal during the turn. Waves will make all even worse.
You can design a ground effect vehicle to also be able to fly. 90+% of the time you get fuel savings utilizing ground effect, and when the sea’s rough you can just increase attitude at a significant increase in fuel usage.
You have put your finger on exactly the reason why they failed commercially in the real world.
The problem is that just one monster wave is disaster. The bigger you make the device, the bigger the wave it can take. But to justify a bigger machine, you need to have it transporting a higher volume of people. Which means that you only hit the break-even point for ground effect vehicles where lots of people want to quickly get from point A to point B over relatively calm seas. And ideally a relatively short distance so you can pick up lots of fares for your time spent over the water.
However wherever you have those conditions, you have the perfect economic conditions to build a bridge or a tunnel. That may be more expensive, but solve the problem better.
They do have limited military use. There you only want to use it once, the people you are transporting can accept higher risk than civilians would, and being able to ignore mines is a huge win. But again, only some military theaters benefit, and getting the machine where it needs to be can be a challenge.
The problem is that just one monster wave is disaster. The bigger you make the device, the bigger the wave it can take. But to justify a bigger machine, you need to have it transporting a higher volume of people. Which means that you only hit the break-even point for ground effect vehicles where lots of people want to quickly get from point A to point B over relatively calm seas. And ideally a relatively short distance so you can pick up lots of fares for your time spent over the water.
However wherever you have those conditions, you have the perfect economic conditions to build a bridge or a tunnel. That may be more expensive, but solve the problem better.
They do have limited military use. There you only want to use it once, the people you are transporting can accept higher risk than civilians would, and being able to ignore mines is a huge win. But again, only some military theaters benefit, and getting the machine where it needs to be can be a challenge.
It should be exhibited alongside the Spruce Goose, Buran, and Stratolaunch, other huge craft which flew once or twice but were never used for anything useful.
I'm not disagreeing with you in the long run, but for now the Stratolaunch company is prepping a hypersonic vehicle to be launched from their carrier.
https://twitter.com/Stratolaunch/status/1319342246186020866
https://twitter.com/Stratolaunch/status/1319342246186020866
It would fit in nicely with a Buran, it is quickly approaching it's current condition :) . Also reasons for building Buran and SM are rather similar.
If you’re ever in the Rhineland, there’s a Buran glider there:
https://speyer.technik-museum.de/en/spaceshuttle-buran
Mayors — add this to the list of cool things you are able to do when your city is situated on a massive navigational river: buy up old stuff and make an awesome technical museum.
https://speyer.technik-museum.de/en/spaceshuttle-buran
Mayors — add this to the list of cool things you are able to do when your city is situated on a massive navigational river: buy up old stuff and make an awesome technical museum.
I wonder how this was worth it. At 550km/hr it's slower than a plane and with 8 turbofans it's certainly more expensive than one.
But it's certainly cool!
But it's certainly cool!
This particular model was designed and built to determine how practical such a system would and could be.
Furthermore, if the Soviets did manage to build a practical, mass-producible design it would have been hell for radar systems (at the time). It "flies" too low for air search radar to pick up due to algorithms and methods used to eliminate false targets from ground clutter. It moves too fast for a surface search radar to register, again because of false target mitigation techniques. It occupies the same blind spot that sea-skimming cruise missiles were designed to exploit, except with much longer range and the ability to spring a half-dozen supersonic Sunburn missiles at the last minute. In a hectic theater it could have been a very effective coastal defense platform and a good complement to the Tu-16/Tu-22 long range missile carriers.
Furthermore, if the Soviets did manage to build a practical, mass-producible design it would have been hell for radar systems (at the time). It "flies" too low for air search radar to pick up due to algorithms and methods used to eliminate false targets from ground clutter. It moves too fast for a surface search radar to register, again because of false target mitigation techniques. It occupies the same blind spot that sea-skimming cruise missiles were designed to exploit, except with much longer range and the ability to spring a half-dozen supersonic Sunburn missiles at the last minute. In a hectic theater it could have been a very effective coastal defense platform and a good complement to the Tu-16/Tu-22 long range missile carriers.
Something like this would be great for ferries. For instance the ~200km Busan-Fukuoka ferry connection is about 2-3 hours with a hydrofoil. With an ekranoplan 550km/h like the Caspian Sea Monster that'd be cut down to like 20 minutes.
it flies in under the radar and hits you at a distance with hypersonic cruise missiles. I think it would be a fearsome weapon even today.
For one thing, it was a (perhaps fanciful) new cold-war weapon intended to give the upper hand in a full-scale invasion of the U.S., so it didn't need to be particularly economical.
For another, only (IIRC) two of the engines are used during cruise. The other six are only used to build up enough speed to break free of the water, and accumulate hours at a much lower rate.
For another, only (IIRC) two of the engines are used during cruise. The other six are only used to build up enough speed to break free of the water, and accumulate hours at a much lower rate.
> new cold-war weapon intended to give the upper hand in a full-scale invasion of the U.S.
This is not true. For one, the Soviet Union never had any plans for the invasion of the U.S.
One thing they did better in the cold war was understanding the political results of potential military actions.
Because of this, they never had any misconceptions of a major conventional war directly between superpowers that lasts more than two weeks before either being resolved or going nuclear. This informed everything about how they built up their military, from the tiniest piece of equipment to overall doctrine. Once you understand this, a lot of their equipment and thinking is a lot more sensible. (For example, the way their logistical organization is set up. A tank division, and the tanks in it, are supposed to give maximum possible effort for about two weeks after which it doesn't matter what shape they are in.)
Any concept of a Soviet invasion of the US is fanciful to the point of being stupid. Just because if the Soviets somehow attain the necessary conventional superiority to attempt it, and then push it, why exactly wouldn't the Americans just nuke them?
This is not true. For one, the Soviet Union never had any plans for the invasion of the U.S.
One thing they did better in the cold war was understanding the political results of potential military actions.
Because of this, they never had any misconceptions of a major conventional war directly between superpowers that lasts more than two weeks before either being resolved or going nuclear. This informed everything about how they built up their military, from the tiniest piece of equipment to overall doctrine. Once you understand this, a lot of their equipment and thinking is a lot more sensible. (For example, the way their logistical organization is set up. A tank division, and the tanks in it, are supposed to give maximum possible effort for about two weeks after which it doesn't matter what shape they are in.)
Any concept of a Soviet invasion of the US is fanciful to the point of being stupid. Just because if the Soviets somehow attain the necessary conventional superiority to attempt it, and then push it, why exactly wouldn't the Americans just nuke them?
The US military maintains plans for invading Canada, defending Puerto Rico against alien attack, and flooding the Netherlands to deny them to the militant Tibetan Buddhist cult which has discovered an effective indoctrination-hypnosis video and is conquering Europe. Plans are just plans. Lots of them are stupid. Planning officers often make strategic plans as simple exercises in considering all factors. You can be assured that Soviet invasion of the US mainland was hardly one of the more farfetched ones, as such things go, though the conditions never came close to presenting themselves.
Nuclear weapons make most military plans "fanciful to the point of being stupid". We've been in a state of unavoidable mutually assured destruction since the late 1960's. This hasn't stopped weapons development. Being able to move large amounts of soldiers and weaponry around at high speed is a generally useful thing.
Nuclear weapons make most military plans "fanciful to the point of being stupid". We've been in a state of unavoidable mutually assured destruction since the late 1960's. This hasn't stopped weapons development. Being able to move large amounts of soldiers and weaponry around at high speed is a generally useful thing.
But you do not develop a new weapons system just to run a speculative planning exercise. If this was not just a military-industrial complex boondoggle - which I suspect it was - I imagine there were some somewhat realistic plans around what it might actually be useful for.
I'll give you one right off the bat where something like this might be useful, in antiship or transport roles:
https://en.wikipedia.org/wiki/Turkish_Straits_crisis
Russia has a lot of inland lakes, and has always defined its empire with non-negotiable geopolitical requirements for blue-water ports on all sides. The countries that pose a threat to those ports generally have a lot of vulnerable coastlines. Fly an ekranoplane empty to a staging area, fill it with a regiment, fly it in boost mode over any land obstacles, and you can rapidly drop significant troop numbers at any point on the coast without control over the body of water.
Larger ekranoplanes that can operate higher off the water are more useful as transports, and things plausibly get much bigger than the KM.
Russia has a lot of inland lakes, and has always defined its empire with non-negotiable geopolitical requirements for blue-water ports on all sides. The countries that pose a threat to those ports generally have a lot of vulnerable coastlines. Fly an ekranoplane empty to a staging area, fill it with a regiment, fly it in boost mode over any land obstacles, and you can rapidly drop significant troop numbers at any point on the coast without control over the body of water.
Larger ekranoplanes that can operate higher off the water are more useful as transports, and things plausibly get much bigger than the KM.
Incompetent bureaucracies do exactly this - "you do not develop a new weapons system just to run a speculative planning exercise". One of significant reasons why USSR failed as a state.
There is no way this would’ve be useful the cross the Atlantic or pacific oceans to invade the continental US.
The only area where this might be useful is in the Great Lakes, at that point the USSR already had to invade Canada at the least and establish a sufficient presence to support these things, and even then it’s not clear if it would be more useful than traditional transport.
These things are cool from an engineering point of view but are quite useless in real world applications.
The only area where this might be useful is in the Great Lakes, at that point the USSR already had to invade Canada at the least and establish a sufficient presence to support these things, and even then it’s not clear if it would be more useful than traditional transport.
These things are cool from an engineering point of view but are quite useless in real world applications.
Probably not across the ocean, but how about having a carrier (like an aircraft-carrier) to carry them across said ocean and then launching these for the last few dozen kms? (This is maybe a dumb plan, because the slow carrier can be easily detected, and the sea might still be bad a few km close to the coast...).
I wonder if cruising over the Arctic ice would've worked...
I wonder if cruising over the Arctic ice would've worked...
I don't think an aircraft carrier can launch the second biggest plane in history, which is also a boat.
Alaska is only 55 miles (88km) from Russia.
"THE BERING SEA, near the chain of the Aleutian Islands, is one of the most intense patches of ocean on Earth. Strong winds, freezing temperatures, and icy water are normal conditions. The combination makes for some of the most ferocious waves on the planet, where the water can rise and fall 30 feet on a normal day."
https://www.nationalgeographic.com/photography/proof/2017/03...
Definitely not the place for these.
https://www.nationalgeographic.com/photography/proof/2017/03...
Definitely not the place for these.
> full-scale invasion of the U.S.
I don't think that's realistic nor has it been the goal of Soviet military doctrine, more likely targets for the Ekranoplan would have been Western Europe and Scandinavia (via the Baltic Sea), Turkey (Black Sea) and Iran (Caspian Sea).
I don't think that's realistic nor has it been the goal of Soviet military doctrine, more likely targets for the Ekranoplan would have been Western Europe and Scandinavia (via the Baltic Sea), Turkey (Black Sea) and Iran (Caspian Sea).
I don't believe you are correct about a full scale invasion of the U.S.
There are two reasons.
The Caspian Sea is a sea and not an ocean. The waves are a fraction of the size of those in the Atlantic. If 'waves were roads' then you would need a four wheel drive equivalent of the 'sea monster' to make it an 'ocean monster'. Ground effect isn't ground effect in quite the same way if you have to fly 50m above the water instead of 5m.
The other reason is that the Soviet Union did not have any realistic ambitions to invade the United States. Their thinking was much more defensive than Western Cold War thinkers were allowing their paranoia to believe.
There are two reasons.
The Caspian Sea is a sea and not an ocean. The waves are a fraction of the size of those in the Atlantic. If 'waves were roads' then you would need a four wheel drive equivalent of the 'sea monster' to make it an 'ocean monster'. Ground effect isn't ground effect in quite the same way if you have to fly 50m above the water instead of 5m.
The other reason is that the Soviet Union did not have any realistic ambitions to invade the United States. Their thinking was much more defensive than Western Cold War thinkers were allowing their paranoia to believe.
Ekranoplanes function better the larger they get. The Caspian Sea Monster was not the endpoint of ekranoplane engineering. It deals well with ~1m wave height. For the Black Sea / Mediterranean sea or the Baltic, a larger version would be required, and for the Atlantic or Pacific, larger still. You could plausibly even fly it over Arctic sea ice fields without bergs.
Boeing was throwing around proposals for a ground effect aircraft several times this large in the early 2000's, with the largest bumping up against the weight range of naval destroyers at ~5000 tonnes.
https://en.wikipedia.org/wiki/Boeing_Pelican
Boeing was throwing around proposals for a ground effect aircraft several times this large in the early 2000's, with the largest bumping up against the weight range of naval destroyers at ~5000 tonnes.
https://en.wikipedia.org/wiki/Boeing_Pelican
It is not getting back in use, kt is only being moved to a new destination:
> After lying dormant for more than three decades, the Caspian Sea Monster has been on the move again. One of the most eye-catching flying machines ever built, it's completing what could be its final journey.
> In July of this year after 14 hours at sea, a flotilla of three tugs and two escort vessels maneuvered slowly along the shores of the Caspian Sea to deliver their bulky special cargo to its destination, a stretch of coast near Russia's southernmost point.
> After lying dormant for more than three decades, the Caspian Sea Monster has been on the move again. One of the most eye-catching flying machines ever built, it's completing what could be its final journey.
> In July of this year after 14 hours at sea, a flotilla of three tugs and two escort vessels maneuvered slowly along the shores of the Caspian Sea to deliver their bulky special cargo to its destination, a stretch of coast near Russia's southernmost point.
The second half of article lists a few new companies who are building new ground effect vehicles.
This is the machine that William Gibson has Hubertus Bigend resurrect and fly to Iceland at the very end of Zero History
A much more technical description of the craft
http://www.hisutton.com/Russian-Navy-Ekranoplan-WIG.html
http://www.hisutton.com/Russian-Navy-Ekranoplan-WIG.html
I wonder how the Airfish is progressing. I haven't seen an update in ages. https://www.wigetworks.com/
I wonder if such solutions are cost effective. Unless they are marketing these services for a very limited (ultra-rich) clientele, in which, it doesn't make any sense. Why buy an airplane that you can only use over sea, and in good conditions? You can use a boat at a fraction of the cost for large numbers of people (purchase, maintenance), or a helicopter for a smaller number of people.
And on planet earth we do get bad weather (even at sea level). It's not as bad as in Interstellar ("these are not mountains"), but it can certainly render this useless.
Unless they target VERY SPECIFIC region (specific parts of Arab peninsula), then we are limiting the use so much that it can only survive as a niche company and not expand much.
And on planet earth we do get bad weather (even at sea level). It's not as bad as in Interstellar ("these are not mountains"), but it can certainly render this useless.
Unless they target VERY SPECIFIC region (specific parts of Arab peninsula), then we are limiting the use so much that it can only survive as a niche company and not expand much.
Helicopters don't tend to like the kinds of conditions that result in the kinds of seas that these ground effect aircraft don't like. Ground effect seaplanes could potentially fill the same niche as helicopters for the offshore oil industry (or anyone else who operates helicopters in coastal waters).
You need something the size of the KM or larger for the sort of waves you get on the calmest day in the Gulf of Mexico. Small ekranoplanes don't work so well in actual oceans.
I reckon they'd be great flying in small-island states that depend heavily on tourism (inter-island travel). AFAIK they are very cheap to run, using gasoline rather than avgas/jetfuel. Think Hawaii, Fiji, the Caribbean nations, Seychelles, Maldives, etc.
Charlie Stross has an interesting story, Missile Gap where nuclear powered ekranoplans are used for long range exploration of "Earth":
https://en.wikipedia.org/wiki/Missile_Gap
https://en.wikipedia.org/wiki/Missile_Gap
And it's an excellent match for this technology, because of the lower power-to-weight ratio sensitivity in ground effect.
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I wonder about the fuel efficiency of such a thing. Jets get to altitude as fast as they can, using a small fraction of their fuel just to take off and land. Thinner air at altitude.
This thing is always 'taking off' at sea level, in the thickest air possible. Fuel efficiency has to be miserable.
This thing is always 'taking off' at sea level, in the thickest air possible. Fuel efficiency has to be miserable.
Flying 5m from the water at 550km/h seems like it would be a hazard to shipping.
> Its intended mission was to conduct lightning sea-borne attacks with the six anti-ship missiles it carried in launch tubes placed at the top of its hull.
Being a hazard to shipping appears to be the purpose of it.
Being a hazard to shipping appears to be the purpose of it.
I assume the parent means "to crash on it", not to sink it with a missile.
I will also say that at 5m from surface, good luck "seeing" it with on a radar. Also, at night and/or with mist.. you don't even see it coming.
I will also say that at 5m from surface, good luck "seeing" it with on a radar. Also, at night and/or with mist.. you don't even see it coming.
Boats use radar to see other boats just fine. As the dramatically faster object it’s job is to avoid other ships not the other way around. As such it can just use forward looking radar and never hit anything unintentionally.
I will go ahead and assume that they see the Transponder signal and not the actual boats.
If by boats you mean warships, then yes, they may cause a blip in a proper radar.
If by boats you mean warships, then yes, they may cause a blip in a proper radar.
No, the current generation of small boat radar are surprisingly capable in both harbors and the open ocean. Decent systems can reliably see a 20’ boat over a mile away in reasonably calm water. Transponders are frequently turned off in harbors for various reasons and are simply not that reliable even in the open ocean.
That said, at longer distances or rough seas things significantly degrade unless you’re talking about a big boat.
That said, at longer distances or rough seas things significantly degrade unless you’re talking about a big boat.
Every time these things are mentioned, I always wonder about that. Now that someone is building a modern equivalent (https://www.wigetworks.com), I wonder what they are doing about avoiding collisions.
Normal aircraft typically spend long periods in autopilot, whereas these things would presumably require a constantly vigilant pilot. And not just to avoid big ships, there are plenty of things floating in the ocean that could destroy one of these things: small boats, buoys, debris. The mast of a small sailing dinghy would be enough to cause a catastrophic crash.
I like the idea of this kind of craft, but I can't see it working at scale.
Normal aircraft typically spend long periods in autopilot, whereas these things would presumably require a constantly vigilant pilot. And not just to avoid big ships, there are plenty of things floating in the ocean that could destroy one of these things: small boats, buoys, debris. The mast of a small sailing dinghy would be enough to cause a catastrophic crash.
I like the idea of this kind of craft, but I can't see it working at scale.
On the KM, the rear engines are the ones used in flight, and they're mounted well above the ground. The front engines are more of a booster to get it airborne, but they are indeed incredibly vulnerable.
You might be able to get it airborne without as much boost if you had the help of an intermediate phase of acceleration as a hydrofoil. The Orylonok uses a ski in this vein.
You might be able to get it airborne without as much boost if you had the help of an intermediate phase of acceleration as a hydrofoil. The Orylonok uses a ski in this vein.
Smaller "Class B" Ekranoplans (like the Orlyonok [1]) could also fly like an airplane, I wonder if "hopping over" ships would be an option also for the bigger ones if avoiding traffic is a design goal (I guess since the Lun was a cold-war weapon system, avoiding civilian traffic wasn't all that important).
[1] https://en.wikipedia.org/wiki/A-90_Orlyonok
[1] https://en.wikipedia.org/wiki/A-90_Orlyonok
What was the deal with the Soviet obsession over contra-rotating coaxial propellers? Was there just one senior designer in the USSR with this obsession and a lot of influence?
I guess in this case the reason is that the Orlyonok simply used the engine of the Tu-95 bomber, this was the most powerful turboprop engine at the time (probably still is).
As for the Kamov helicopters, no idea, but apparently coaxial rotors are more efficient (e.g. better climb rate) than the traditional helicopter design. The "next generation" Sikorsky–Boeing SB-1 also uses coaxial rotors:
https://en.wikipedia.org/wiki/Sikorsky%E2%80%93Boeing_SB-1_D...
As for the Kamov helicopters, no idea, but apparently coaxial rotors are more efficient (e.g. better climb rate) than the traditional helicopter design. The "next generation" Sikorsky–Boeing SB-1 also uses coaxial rotors:
https://en.wikipedia.org/wiki/Sikorsky%E2%80%93Boeing_SB-1_D...
> I wonder if "hopping over" ships would be an option
Yes, at the cost of forward speed. It would be similar to a parabolic climb in an aircraft.
Yes, at the cost of forward speed. It would be similar to a parabolic climb in an aircraft.
It wouldn't be that hard to put a scanning radar at the front of the thing and look 10 miles ahead so you have time to steer around others.
At about 10m height the horizon is only ~11km away - fine for a ship but if you are going 550km/h in something that doesn't look wildly manoeuvrable it might be quite exciting.
Still gives you a full minute to steer around something. But probably requires some automated system to decide on "collision or not" because that would be hard to do on time manually at such a distance.
If you start steering 30 seconds after detecting an object you would still be 5+ km away, so assuming a ship is at most 200m long you would only need a 3 degree course change to miss it by more than a ships length. Maybe make it 5 degrees to miss it by 400+ meters.
If you start steering 30 seconds after detecting an object you would still be 5+ km away, so assuming a ship is at most 200m long you would only need a 3 degree course change to miss it by more than a ships length. Maybe make it 5 degrees to miss it by 400+ meters.
The noise in the cockpit from all those engines very close must have been deafening.
> Today, the Ekranoplan–the only Lun ever built—lies stranded off a beach in the Caspian Sea. This summer, the craft was in the process of being towed from a nearby naval base to a museum when something appeared to have gone terribly wrong. Instead of making it to its new home, the Ekranoplan ended up stranded in shallow water, where it's drawing visitors. https://www.popularmechanics.com/military/aviation/a33808381...
However, this article today claims that the beach was the intended destination:
> "Lun" will be the star of Derbent's planned Patriot Park, a military museum and theme park that will display different sorts of Soviet and Russian military equipment. Construction of the park is expected to start later in 2020. For the time being, Lun will sit alone on the beach.
Checking the famous photo article that was already linked from that article two months ago, it seems that the “something appeared to have gone terribly wrong” was just speculation by Popular Mechanics:
> This summer, Russian urban explorer Lana Sator, 31, read about the ekranoplan being towed by sea to Derbent, a city in Daghestan, where it is due to be moved into a "patriotic park” and put on permanent display. https://www.rferl.org/a/photographer-sneaks-inside-the-legen...
Derbent is on the west shore of the Caspian Sea, close to Azerbaijan: https://www.openstreetmap.org/search?query=derbent%2C%20dagh...