UAV for the new OPV's?

[The real Jack]

I'll eat my hat when a kite manages to pull a few thousand tons of steel and saves fuel in the process.

[DeV]

Yep and that article is from 2014 - haven't seen any pictures or reports of trials as of yet.

http://www.seai.ie/News_Events/Press...-SeaFest-.html

[pym]

http://www.seai.ie/News_Events/Press...-SeaFest-.html

Cheers, a land based stationary demo - that's what I meant.

[DeV]

I know but that's all I have to offer

[ancientmariner]

Cheers, a land based stationary demo - that's what I meant.

There is a long way between laboratory theory, and display testing, with real time use at sea. Such systems will be very much subject to weather conditions and the breaking strain of the launch wire and the capacity of the winch to reel it in in a sudden squall. the weather at 300m is often different to sea level conditions. Have any of the frontline Navies tried it or do they prefer Blimps and MPA's with the Mark 1 eyeball.

[pym]

I don't that at all - which makes the turnaround time in the DARPA project all the more impressive.

The variable of course is the funding.

[morpheus]

few more articles from around june / jily that i found and a discussion on reddit which i havent bothered reading.

http://www.irishtimes.com/business/h...osts-1.2296224

http://www.irishtimes.com/news/crime...ites-1.2297873

https://www.reddit.com/r/ireland/com...g_fuel_saving/

[ancientmariner]

few more articles from around june / jily that i found and a discussion on reddit which i havent bothered reading.

http://www.irishtimes.com/business/h...osts-1.2296224

http://www.irishtimes.com/news/crime...ites-1.2297873

https://www.reddit.com/r/ireland/com...g_fuel_saving/

This sail away story is detracting from various uses of sails. The usual visual horizon, stated by The Irish Times, is not ever 200 miles.According to my Tables the sea horizon at 10 metres, height of eye is 6.57 miles away, and at 300 metres is 36.02 miles away. Seeing 3000 miles away is poppycock giving the curvature of mother Earth. The articles in general are an offence to genuine research and are in the same category as Turlough Hill electricity generation. There are NO free lunches.

[Sparky42]

It's been a while but an interesting article on something the DARPA is working on:
https://chuckhillscgblog.net/2017/02...oot-container/

[Graylion]

I'll eat my hat when a kite manages to pull a few thousand tons of steel and saves fuel in the process.

Enjoy! http://www.skysails.info/english/ Want some mustard with that?

[The real Jack]

They're not pulling much mustard in one tech demonstrator, for such a world saving technology it's odd they've transitioned to flogging performance management software for non kitey ships. I can't find any recent news about the project either.

[ancientmariner]

They're not pulling much mustard in one tech demonstrator, for such a world saving technology it's odd they've transitioned to flogging performance management software for non kitey ships. I can't find any recent news about the project either.

.

all this Kite stuff is a long way from UAV's, which at least are controllable and can do specific observational or interdiction tasks. Kites will only work if the wind suits the direction in which the ship wishes to travel. The idea of kite sails on ships has a certain merit but also introduces hazards and inconveniences that add to the shipboard burdens for crews.

[Jetjock]

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all this Kite stuff is a long way from UAV's, which at least are controllable and can do specific observational or interdiction tasks. Kites will only work if the wind suits the direction in which the ship wishes to travel. The idea of kite sails on ships has a certain merit but also introduces hazards and inconveniences that add to the shipboard burdens for crews.

It's mooted use as a sensor platform within the NS is also dubious, as you would end up with an expensive system with certain weather limitations that is usable only some of the time. The technical aspect of sensor integration is mind boggling to say the least.These kites fly figure of eight patterns to stay in the sky. The processing capability needed to come up with any usable information from a kite mounted array is huge.

If you need better situational awareness and on board systems are insufficient, build the ships with aviation capability. Simply put there are no vessels anywhere near the size of the P60 worldwide being built without a flightdeck and hangar. A kite is not the answer.

Then there is the absolute ridiculousness of an overt kite on a supposedly covert platform. It's going to light up on even the most basic radar. The function of a NS vessel is not to save fuel. The cynic in me wonders if given the long lead time for this project, that this is all just an effort to be seen to be proactive about cost saving.

[DeV]

It's mooted use as a sensor platform within the NS is also dubious, as you would end up with an expensive system with certain weather limitations that is usable only some of the time. The technical aspect of sensor integration is mind boggling to say the least.These kites fly figure of eight patterns to stay in the sky. The processing capability needed to come up with any usable information from a kite mounted array is huge.

If you need better situational awareness and on board systems are insufficient, build the ships with aviation capability. Simply put there are no vessels anywhere near the size of the P60 worldwide being built without a flightdeck and hangar. A kite is not the answer.

Then there is the absolute ridiculousness of an overt kite on a supposedly covert platform. It's going to light up on even the most basic radar. The function of a NS vessel is not to save fuel. The cynic in me wonders if given the long lead time for this project, that this is all just an effort to be seen to be proactive about cost saving.

It's an R&D job

[ancientmariner]

It's an R&D job

The bottom line for all Naval packages aboard ship is that the derivation of New concepts should come from Naval Sources, or it's allied industries. Such improvements should make the equipped vessel a better fighting platform. We can help out Marine Industry in certain projects but remember we are NOT an adjunct of Industry or it's R&D. There are many out there think the Naval Service is a free platform for their projects.

[DeV]

The bottom line for all Naval packages aboard ship is that the derivation of New concepts should come from Naval Sources, or it's allied industries. Such improvements should make the equipped vessel a better fighting platform. We can help out Marine Industry in certain projects but remember we are NOT an adjunct of Industry or it's R&D. There are many out there think the Naval Service is a free platform for their projects.

It is Government, DoD, DF and NS policy to engage with Irish enterprises and educational institutions.

It is not as if the "Writer" class are being delivered with BFO kites permanently attached

[ancientmariner]

It is Government, DoD, DF and NS policy to engage with Irish enterprises and educational institutions.

It is not as if the "Writer" class are being delivered with BFO kites permanently attached

Yes, Engage where possible for our benefit such as professional equivalency between Service grades and courses run by 3rd level Institutes. Looking at kites ,such as SKYSAILS demo videos, it is clear they are unstable and uncontrollable by nature. They sheer and oscillate from Port to Starboard and back again in the following wind as seen. I do not see how it would also provide a stable electronic observational platform with accurate positional information of distant targets.

[pym]

Yep there are a whole variety of issues with the sails, but hey if nothing else, I guess it would be a nice HF antenna

If they do find their way on to a NS vessel, I'll take a wild guess and say it will ultimately just be for a trade mission to China or the like as a R&D demo - for operational purposes though... just too many issues.

[danno]

For a radar to see out 3000 miles or whatever is being claimed a fair bit of watts would be needed to power the system.

[Jetjock]

For a radar to see out 3000 miles or whatever is being claimed a fair bit of watts would be needed to power the system.

Most likely square miles. Then there's the computer processing required to decipher anything useful from a radar platform that is moving rapidly in 3 axis relative to the platform below and the sweep area of the radar.

[Archimedes]

Yes, Engage where possible for our benefit such as professional equivalency between Service grades and courses run by 3rd level Institutes. Looking at kites ,such as SKYSAILS demo videos, it is clear they are unstable and uncontrollable by nature. They sheer and oscillate from Port to Starboard and back again in the following wind as seen. I do not see how it would also provide a stable electronic observational platform with accurate positional information of distant targets.

The figure of 8 that the SkySails kite performs is done deliberately to keep the kite flying in the middle of the power zone. At launch and recovery, the kite is put into 12 o'clock mode where it points straight up until it is flying stably almost directly overhead. If it were to have a radar onboard, you would switch to this mode every few minutes to do a few sweeps and then revert to power mode.

The system currently being developed will use a much smaller kite, not designed for power which will be stable all of the time and not do figure of 8s. The radar will have a range of 40nm as compared to about 12nm from the mast of a ship. This is limited by the size and power or the radar rather than the height of the platform.

The point about a warship not wanting to fly a big sign saying "here I am" may be valid in certain scenarios but not when you have a handful of ships searching the vast expanse of the Irish EEZ for needles in a haystack.

[ancientmariner]

Radar horizon and radar range are dependent on the radar antenna height, and crucially the nature and height of the target. For example if radar is at a height of 15metres, then horizon range is 8.5 nm. To achieve 40nm the antenna would have to be at a height of 328metres. If the target in the first case was land at 30metre height then it could be picked up at 8.5nm+12.1nm giving a total of 20.6 nm for the mast based antenna on a normal ship.Assuming a ship with about 9metres height was your target , then an aerial height of 230metres would be required to see it at 40nm ie 6.6 + 33.5 or 40.1 nm. I think all in all, a ship launched drone might be more useful in operational surveillance.

[DeV]

Radar horizon and radar range are dependent on the radar antenna height, and crucially the nature and height of the target. For example if radar is at a height of 15metres, then horizon range is 8.5 nm. To achieve 40nm the antenna would have to be at a height of 328metres. If the target in the first case was land at 30metre height then it could be picked up at 8.5nm+12.1nm giving a total of 20.6 nm for the mast based antenna on a normal ship.Assuming a ship with about 9metres height was your target , then an aerial height of 230metres would be required to see it at 40nm ie 6.6 + 33.5 or 40.1 nm. I think all in all, a ship launched drone might be more useful in operational surveillance.

Kites don't need to return to the vessel to refuel

It isn't the only tool in the box it will/would give the commander more options

[Graylion]

as regards processing power - a masthead is not exactly holding still, so the issue is not unique to a kite. Amplitude and frequency may both be higher, but it is a solved problem and the computing power should be easily provided by a modern PC - of the more powerful variety.

[Medsailor]

Kites don't need to return to the vessel to refuel

It isn't the only tool in the box it will/would give the commander more options

Its more a question of what you are actually mounting on the kite. The radar antenna only, the antenna and transceiver, antenna transceiver and signal processor? If its only the former then the losses in 250+ metres of waveguide/coax will be wicked, if the latter then weight becomes an issue and the kite starts to get pretty big.