Indonesia Indonesian Navy, Tentara Nasional Indonesia-Angkatan Laut (TNI-AL)

norman88

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According to official sources, thanks to the full LIBs configuration, the Scorpene Evolved will have a total endurance of 80 days (with 78 of those submerged), an operational range of more than 8,000 nautical miles, a lower indiscretion rate, and maintain top speed longer. This can be achieved because LIBs can store and deliver more energy with shorter charging times than lead-acid batteries.

Meaning of "submerged" in this case maybe "total submerged endurance" which mean with and without snorkeling. Because it's almost impossible for non-nuclear subs can fully submerged for 78 days without snorkeling (to recharge batteries)

In comparison, KSS-III which combines AIP+Lithium-ion, only get 20+ days to fully submerged without snorkeling.

And 9 days on soryu subs lithium-ion. (Estimated)
 

Gary

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Meaning of "submerged" in this case maybe "total submerged endurance" which mean with and without snorkeling. Because it's almost impossible for non-nuclear subs can fully submerged for 78 days without snorkeling (to recharge batteries)

In comparison, KSS-III which combines AIP+Lithium-ion, only get 20+ days to fully submerged without snorkeling.

And 9 days on soryu subs lithium-ion. (Estimated)
good point
 

this is crunch

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I'm a bit skeptical towards this programme, there is just too many works need to be done to make it feasible for operational use, i think there is 2 main argument from me about this very ship.

1. Learning from the past, TNI AL couldn't afford the financial burden to operate such thirsty fuel gas-turbine engine for ships and its waterjet propeller. And also its problematic gearbox system become real nightmare if not replaced with conventional one. What's the use of having something that's not even useful to its original operator.

For the case of waterjet propeller,it's already happened with KRI Karang Tekok, on that ship, the 4 waterjet propeller needs to be replaced with conventional 2 shafted propeller to reduce operational cost. It was such thirsty machine, the quad prop-jet drinks abt 2 tonne diesel fuel per hour, compared to after refit with conventional 2 shaft propeller which they says reduce it significantly to 2 tonne fuel per day (on that very ship).


2. The mission package is very "patrol ship" than a corvette or light frigate, no hull mounted sonar, no torpedo launcher, no AShM, and no VLS for AA missile.


Unless MoD really want this very ship to fill the gap, and prepared the budget and time for those repair-refit-upgrade, then i could say less.

But if they buy it as is, i personally highly oppose that decision.
 

Anmdt

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, the quad prop-jet drinks abt 2 tonne diesel fuel per hour
Water-jets in fact is fuel-efficient if driven in lower speeds. They are fuel-hungry at high speeds that propellers can not be used (and if able to be used, would drain the fuel tanks).

There are two kind of efficiencies for hydrodynamics of propulsors.
1st, propulsor efficiency, efficiency of the lone propulsor unit, excluding integration with the vessel and mechanical transmissions, as well as shafting, it is the lone propulsor, if propeller merely propeller rotating in an open water; if water-jet assembly of stator-rotors and shrouding - inlet - outlet in open water.
1697293505199.jpeg


Then there comes overall efficiency, assuming integration with the hull (thus the velocity profile subjected on propulsor, usually increases the efficiency) accounting for mechanical losses due to the shafting etc.
1697293547726.jpeg
 

this is crunch

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Water-jets in fact is fuel-efficient if driven in lower speeds. They are fuel-hungry at high speeds that propellers can not be used (and if able to be used, would drain the fuel tanks).

There are two kind of efficiencies for hydrodynamics of propulsors.
1st, propulsor efficiency, efficiency of the lone propulsor unit, excluding integration with the vessel and mechanical transmissions, as well as shafting, it is the lone propulsor, if propeller merely propeller rotating in an open water; if water-jet assembly of stator-rotors and shrouding - inlet - outlet in open water.
View attachment 61887

Then there comes overall efficiency, assuming integration with the hull (thus the velocity profile subjected on propulsor, usually increases the efficiency) accounting for mechanical losses due to the shafting etc.
View attachment 61888
wow thats actually new insight for me, but that's also sparks another question, if naval ships, (like patrol boat, corvette and maybe frigate) rarely operate in high speed, then why don't they massively used waterjet props, which you said more efficient in slower speed than propeller?

i mean, i recall something but not recalling the source, about Indonesian Ship, idk if its the navy or the coast guard. Even if they are in dire situation, they don't go full throttle, for like 25++ knots but maintain cruising speed, for which typically 15-18 knots, (right(?)).

That means full throttle is not everyday use. I began to think that full throttle or full ships ahead is just the maximum capability of its propulion system, not necesessary used, but it's there if you need it.
 
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Anmdt

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wow thats actually new insight for me, but that's also sparks another question, if ships rarely operate in high speed, then why don't they massively used waterjet props, which you said more efficient in slower speed than propeller?
Conventional propellers are still more efficient up to 20 knots by a great margin (10% to 40% and here commercial shippers could mind even 1% efficiency), at 20 to 30 knots these systems are head to head. +20 knots are usually not preferred by commercial vessels/ferries, there are only few with topping 30 knots and at that point they value simplicity over complexity of a waterjet.

Also a waterjet are limited to a size, while propellers are not (technically, might differ practically).

In fact waterjets are common with ferries that do not exceed 30 knots too, entertainment boats (jetskis for also safety reason) etc.

It is a balance between;
  1. Initial costs
  2. Maintenance costs
  3. Operation costs (fuel - lubrication - manning)
  4. Mission profile (speed profiles of a vessel, as in how often high speed regimes will be visited)
  5. Necessity of high-speed regimes (Depends on operator if high speed regimes are required despite of 1-2-3).
  6. Design volume restrictions (waterjets occupy less volume, smaller transition, less weight, easy to include in design as rotator-stator comes with fixed geometries)
Based on these you may also see propeller using boats topping 40 knots, or waterjet using ferries not exceeding 25 knots.
 

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Conventional propellers are still more efficient up to 20 knots by a great margin (10% to 40% and here commercial shippers could mind even 1% efficiency), at 20 to 30 knots these systems are head to head. +20 knots are usually not preferred by commercial vessels/ferries, there are only few with topping 30 knots and at that point they value simplicity over complexity of a waterjet.

Also a waterjet are limited to a size, while propellers are not (technically, might differ practically).

In fact waterjets are common with ferries that do not exceed 30 knots too, entertainment boats (jetskis for also safety reason) etc.

It is a balance between;
  1. Initial costs
  2. Maintenance costs
  3. Operation costs (fuel - lubrication - manning)
  4. Mission profile (speed profiles of a vessel, as in how often high speed regimes will be visited)
  5. Necessity of high-speed regimes (Depends on operator if high speed regimes are required despite of 1-2-3).
  6. Design volume restrictions (waterjets occupy less volume, smaller transition, less weight, easy to include in design as rotator-stator comes with fixed geometries)
Based on these you may also see propeller using boats topping 40 knots, or waterjet using ferries not exceeding 25 knots.
So if i take it with a grain of salt, the waterjets on LCS Freedom is actually feasible enough when it comes to certain speed, but whats not feasible, is the gearbox system and its gas-turbine engine?
 

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So if i take it with a grain of salt, the waterjets on LCS Freedom is actually feasible enough when it comes to certain speed, but whats not feasible, is the gearbox system and its gas-turbine engine?
Gas turbine engines are not as efficient as diesel engines, however diesel engines with same power output are huge for the warships. So there is a trade-off. The vessels are also equipped with diesel engines for cruising speed.

However, Gas turbine to waterjet gearboxes are also more efficient than gas turbine to propeller reductors.

The core of the "inefficiency" is forcing such large hulls to experience high speed regime at continuous use. Even if conventional propellers with conventional engines are used for the same speed regime (40+ knots), the fuel consumption will not go lower.
 

this is crunch

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Gas turbine engines are not as efficient as diesel engines, however diesel engines with same power output are huge for the warships. So there is a trade-off. The vessels are also equipped with diesel engines for cruising speed.

However, Gas turbine to waterjet gearboxes are also more efficient than gas turbine to propeller reductors.

The core of the "inefficiency" is forcing such large hulls to experience high speed regime at continuous use. Even if conventional propellers with conventional engines are used for the same speed regime (40+ knots), the fuel consumption will not go lower.
So changing waterjet to propeller and gas turbine to diesel doesn't necessarily important need when it comes to power and propulsor efficiency. Ship doesn't always in high speed regime, so that the waterjets is more efficient than props in slow and or in certain speed, Also even if it's on high speed, Both propeller and waterjets consume fuel as high as they could.

I understand. This is very insightful discussion, i express my gratitude sire.
 

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So changing waterjet to propeller and gas turbine to diesel doesn't necessarily important need when it comes to power and propulsor efficiency. Ship doesn't always in high speed regime, so that the waterjets is more efficient than props in slow and or in certain speed, Also even if it's on high speed, Both propeller and waterjets consume fuel as high as they could.

I understand. This is very insightful discussion, i express my gratitude sire.
I have told so on basis of LCS project, that changing from gas turbine to diesels or waterjets to propeller may not have increased the efficiency for speeds above 20 knots. (20 knots is a slow speed for a vessel capable of 45 knots).

However depending on design philisophy, one of these solutions may have been more efficient than the other. It can not be simply generalized.
 

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Turkish CMS, sonar, torpedo for Indonesian type 214.
It is not valid anymore. The offer was made a decade ago in collaboration of HDW-Golcuk Shipyard, now TKMS makes the offer alone. There is no reason for Indonesian Navy to ask for Turkish CMS and electronics, there is no reason for TKMS to offer Turkish components.

However they may offer revised version built for TN called as 214TN.
 

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