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dixontj93060

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So took a look at this picture the new Chinese aircraft carrier and it seems so intuitively obvious to add the slope to the entry/exit. Searching quickly, it looks like this approach is also done by India and Russia. I don't think I have ever seen this design on a U.S. aircraft carrier (but I'm no expert)--why not?

BBAnKIp.jpg
 
The U.S. uses steam catapults, and on the newer carriers the U.S. is going with electric catapults, I know you know that. Cheaper I guess to not use them,less maintenance, and also the new Chinese carrier is not nuclear powered. Need lots of extra fuel to generate the steam or electricity for a catapult on a conventionally powered carrier. The British also use the "ski jump" method. With a catapult the options of which aircraft can be launched is much greater, and they can launch much heavier aircraft also.
 
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So took a look at this picture the new Chinese aircraft carrier and it seems so intuitively obvious to add the slope to the entry/exit. Searching quickly, it looks like this approach is also done by India and Russia. I don't think I have ever seen this design on a U.S. aircraft carrier (but I'm no expert)--why not?

View attachment 318572

IIRC its called a ski jump bow, the British have used it as well for their Harrier type aircraft. Its used for launching only, recovery is still over the tail like US carriers. The Indian carrier is actually a former Russia carrier, as is that Chinese carrier. All three are Kuznetsov-class. None of them have catapults.
 
I just find it amazing that they (air craft carriers) don't roll / tip over.. Same with cruise ships.. 30+ feet of draft and 100+ feet above the water line..
 
I just find it amazing that they (air craft carriers) don't roll / tip over.. Same with cruise ships.. 30+ feet of draft and 100+ feet above the water line..

Gyro stabilization...
 
I like the flags and ribbons. Makes everything look pretty and benign.
 
As rcktnut has said, catapults can launch much heavier aircraft. I believe the ski jump bow requires STOL aircraft so they really are limiting. Also, I think catapults can be used in rougher weather.
 
I just find it amazing that they (air craft carriers) don't roll / tip over.. Same with cruise ships.. 30+ feet of draft and 100+ feet above the water line..

Ship stability is what I did for a long time, though I've added other responsibilities since. Lots of width at the waterline helps an awful lot. In round numbers, ship stability goes up by the square of the waterline width. When you're as wide as a carrier or cruise ship, a little extra beam gets a lot of benefit. It's a tradeoff against efficiency through the water, but nothing goes fast if it's rolled over.

Gyro stabilization...

Not sure if that was a joke or not--there are gyros for smaller boats, but an aircraft carrier would take a gyro of epic proportions.
 
Little hometown newspaper in adjacent county's county seat has link to ABC News article https://www.fayettenewspapers.com/syndicated_post/why-chinas-new-aircraft-carrier-is-significant/
Both ships suffer some of the limitations inherent in the design, including a ski jump-style launching system that limits the amount of fuel and bombs its Chinese J-15 fighters can carry. Michael Chase of the U.S. think tank RAND Corporation said the carriers reflect the progress China's has made in shipbuilding and other defense industries, and future carriers will be even more sophisticated, particularly in their propulsion and aircraft launch systems.
But, yeah, your first, "Look ma! I made it myself!" aircraft carrier is cause for a large celebration.

Okay, that's why its name is hard to find, probably not going to find a thing which doesn't exist;
The as-yet-unnamed carrier joins the Liaoning, a repurposed 1980s-era Soviet ship that was bought from Ukraine and launched in 2012.
https://www.npr.org/sections/thetwo...lebrates-launch-of-home-made-aircraft-carrier
 
Hmm, doesn't seem to be anything about it on ship-technology but they seem to be more about civilian ships anyway.
This is kinda interesting, though,
China began construction of a new polar research vessel and icebreaker in December 2016. The ship will be operated by the Polar Research Institute of China (PRIC).

The PRIC placed a contract with Aker Arctic for the concept and basic design of the new polar research vessel in 2012. The shipbuilding works of the domestic-built polar research vessel started with the construction commencement ceremony at Jiangnan Shipyard in Shanghai, China, in December 2016.

Scheduled to be delivered in 2019, the ship will complement the Xuelong research vessel and icebreaker that is in service with the PRIC and will allow the country to research marine environments and resources.
https://www.ship-technology.com/projects/chinese-polar-research-vessel/

And then really off on a tangent,
Asleep at the helm: the dangerous impacts of seafarer fatigue
At the beginning of this year, maritime trade association InterManager released the initial findings of Project MARTHA, the most comprehensive study on seafarer fatigue so far. What did the industry learn about the difficulties seafarers face at sea, and who is best placed to help?
https://www.ship-technology.com/fea...angerous-impacts-of-seafarer-fatigue-5782587/

Meanwhile, back at the carrier ... let's go see if G Captain has something about it.
Nope.
But there is some rocket news;
A Long March 4C rocket carrying a new high-resolution Maritime Synthetic Aperture Radar imaging satellite blasts off at the Taiyuan Satellite Launch Center in Taiyuan, capital of north China’s Shanxi Province, Aug. 10, 2016.
https://gcaptain.com/china-launches-high-resolution-maritime-surveillance-satellites/

And ... one last tangent,
https://gcaptain.com/coast-guard-earned-iconic-orange-blue-stripe/
How The Coast Guard Earned Its Orange And Blue Stripes
April 20, 2017 by gCaptain
by Diana Honings – In the modern history of the United States Coast Guard, there has been a rapid shift from mistaken identity to a brand identity. The iconic orange and blue Racing Stripe – painted on the bow of every USCG vessel – provides a perfect example of an innovative solution to this identity problem. But where did the idea come from?
 
Gyro stabilization...

LOL
Old school Weight and Moment calculations done on every drawing that puts stuff on, takes stuff off, or moves it around. Live listing and hogging is corrected by shifting JP-5 or water from tanks on one side to tanks on the other another
 
So took a look at this picture the new Chinese aircraft carrier and it seems so intuitively obvious to add the slope to the entry/exit. Searching quickly, it looks like this approach is also done by India and Russia. I don't think I have ever seen this design on a U.S. aircraft carrier (but I'm no expert)--why not?

View attachment 318572
The difference between our "flat top" carriers and the "ski jump" type are a result of jet engine technology over time, mission profile, and economy. As the U.S. Navy moved to jet powered flight in the late 40's and early 50's--under powered at the time-- the catapult was only practical way to launch an aircraft. And at that time, no other navy had a carrier in their fleet except the Brits and the French. Ultimately they no longer could support a blue water navy let alone develop specialized naval aircraft. The U.S. carrier continued to evolve at the same time as well as it's task force. The large angle decks came along with four "cats" followed by nuclear power.
The "cat" gave the carrier the ability to launch any number of different types of aircraft since the power could be dialed up to the weight of the aircraft. The payload of the aircraft was not a concern. As an example, we would shoot fully loaded A-7's and A-6's at nearly the same pressures as an F-14. They literally "SHOT" off the deck! The "cat" also allowed U.S. carriers to launch larger aircraft such as the C-2 COD and the E-2 Hawkeye. This made the U.S. carriers effectively independent of land resources to some degree. The Navy got good at the carrier business
--REALLY GOOD--.
With the advent of the Harrier, the Brits had a marginal but novel aircraft. With vertical take off it had limited range and payload--but-- give it a ramp and a running start and it was a game changer. Newer , more modern aircraft have a lot of excess power so the ramp suites them well for taking off of a ship with a usable payload. Their land bound counter parts still have more range and payload. The fact of the mater is, they air air force planes, forced into a role they are not designed for--nothing more than a stop gap!
China,Russia,India,and the UK ,all have or are developing "ski jump"carriers. Since they are only regional players, it makes sense to them. Against each other they present a very real threat since they are on equal footing. There is no real comparison to the these carriers or their limited task forces and ours. While they do represent a level of danger to us in the case of China and Russia. In the big scheme of things they are easily brushed aside.
 
The difference between our "flat top" carriers and the "ski jump" type are a result of jet engine technology over time, mission profile, and economy. As the U.S. Navy moved to jet powered flight in the late 40's and early 50's--under powered at the time-- the catapult was only practical way to launch an aircraft. And at that time, no other navy had a carrier in their fleet except the Brits and the French. Ultimately they no longer could support a blue water navy let alone develop specialized naval aircraft. The U.S. carrier continued to evolve at the same time as well as it's task force. The large angle decks came along with four "cats" followed by nuclear power.
The "cat" gave the carrier the ability to launch any number of different types of aircraft since the power could be dialed up to the weight of the aircraft. The payload of the aircraft was not a concern. As an example, we would shoot fully loaded A-7's and A-6's at nearly the same pressures as an F-14. They literally "SHOT" off the deck! The "cat" also allowed U.S. carriers to launch larger aircraft such as the C-2 COD and the E-2 Hawkeye. This made the U.S. carriers effectively independent of land resources to some degree. The Navy got good at the carrier business
--REALLY GOOD--.
With the advent of the Harrier, the Brits had a marginal but novel aircraft. With vertical take off it had limited range and payload--but-- give it a ramp and a running start and it was a game changer. Newer , more modern aircraft have a lot of excess power so the ramp suites them well for taking off of a ship with a usable payload. Their land bound counter parts still have more range and payload. The fact of the mater is, they air air force planes, forced into a role they are not designed for--nothing more than a stop gap!
China,Russia,India,and the UK ,all have or are developing "ski jump"carriers. Since they are only regional players, it makes sense to them. Against each other they present a very real threat since they are on equal footing. There is no real comparison to the these carriers or their limited task forces and ours. While they do represent a level of danger to us in the case of China and Russia. In the big scheme of things they are easily brushed aside.

Thanks for that more detailed explanation.
 
The difference between our "flat top" carriers and the "ski jump" type are a result of jet engine technology over time, mission profile, and economy. As the U.S. Navy moved to jet powered flight in the late 40's and early 50's--under powered at the time-- the catapult was only practical way to launch an aircraft. And at that time, no other navy had a carrier in their fleet except the Brits and the French. Ultimately they no longer could support a blue water navy let alone develop specialized naval aircraft. The U.S. carrier continued to evolve at the same time as well as it's task force. The large angle decks came along with four "cats" followed by nuclear power.
The "cat" gave the carrier the ability to launch any number of different types of aircraft since the power could be dialed up to the weight of the aircraft. The payload of the aircraft was not a concern. As an example, we would shoot fully loaded A-7's and A-6's at nearly the same pressures as an F-14. They literally "SHOT" off the deck! The "cat" also allowed U.S. carriers to launch larger aircraft such as the C-2 COD and the E-2 Hawkeye. This made the U.S. carriers effectively independent of land resources to some degree. The Navy got good at the carrier business
--REALLY GOOD--.
With the advent of the Harrier, the Brits had a marginal but novel aircraft. With vertical take off it had limited range and payload--but-- give it a ramp and a running start and it was a game changer. Newer , more modern aircraft have a lot of excess power so the ramp suites them well for taking off of a ship with a usable payload. Their land bound counter parts still have more range and payload. The fact of the mater is, they air air force planes, forced into a role they are not designed for--nothing more than a stop gap!
China,Russia,India,and the UK ,all have or are developing "ski jump"carriers. Since they are only regional players, it makes sense to them. Against each other they present a very real threat since they are on equal footing. There is no real comparison to the these carriers or their limited task forces and ours. While they do represent a level of danger to us in the case of China and Russia. In the big scheme of things they are easily brushed aside.

Yes,, thank you for this Hornet,, very cool post..
I thought they had to balance the mass of the aircraft and everything on / in it,,
with the force the catapult is set to launch them at
or they run the risk of damaging the front landing gear...
Has damage to a front gear ever occurred ??
Is it a serious concern ??
Or is it possible to just over build the front gear by enough of a margin so as to eradicate the concern....

Teddy
 
I get the function of the ski jumps and how the catapults came to be. What I'm still stuck on is how carriers effectively operated before those things were developed. Were prop-driven WWII vintage fighters fast enough off the line to just make a standard take off run down the length of the deck? And how the hell did they launch 16 loaded B-25s off of the Hornet, in bad weather no less?
 
I get the function of the ski jumps and how the catapults came to be. What I'm still stuck on is how carriers effectively operated before those things were developed. Were prop-driven WWII vintage fighters fast enough off the line to just make a standard take off run down the length of the deck? And how the hell did they launch 16 loaded B-25s off of the Hornet, in bad weather no less?



There were some catapults used in WW2. The early ones were a lot less efficient than now, hydraulically, air, even powder (cordite) powered. For the heavier aircraft, they used rocket assisted take off.
 
Before one can sink a carrier one must get there and/or get the weapon there.
https://foxtrotalpha.jalopnik.com/what-it-would-really-take-to-sink-a-modern-aircraft-car-1794182843
The modern aircraft carrier is a global symbol of American dominance, hegemony, peace, even empire. But at over 1,000 feet long, and displacing more than 100,000 tons, is it a sitting duck? Is the massive emblem of American greatness just an obsolete, vulnerable hunk of steel?

There’s a lot of consternation about whether or not the United States should even have massive supercarriers anymore. Obviously, the answer here is “depends on how much explosives you’ve got.” But while sinking an aircraft carrier is difficult, it’s not impossible. The key is what it’s used for, and who it’s used against. But if you wanted to sink one, here’s what you’d have to do, and what you’d be up against.

(Professor Robert Farley is a specialist in military diffusion, maritime affairs, and national security at the Patterson School of Diplomacy and International Commerce at the University of Kentucky. He took exception to our original piece on carrier vulnerability, and seeing as how he’s an expert, we offered him a chance to do us one better. - M.B.)

https://www.lexingtoninstitute.org/wp-content/uploads/aircraft-carrier-invulnerability.pdf
The purpose of this study is to assess the severity of threats to U.S. aircraft carriers over the next twenty years. The study
reviews the tasks that an adversary would have to accomplish in order to find, target, attack and disable a carrier, and then examines whether potential enemies are in fact acquiring the required capabilities. The study concludes that, barring a major tactical blunder, aircraft carriers are likely to remain highly survivable for many years to come.

This report was prepared by Dr. Loren Thompson of the Lexington Institute staff. All members of the Naval Strike Forum
had an opportunity to review and modify the final report.
 
Prior to jets, take off speeds were much lower. The bad weather actually helped the Tokyo Raid B-25's as the ship pointed into the wind. Also, they were considerably lightened (guns removed, etc.,) for the mission.

I get the function of the ski jumps and how the catapults came to be. What I'm still stuck on is how carriers effectively operated before those things were developed. Were prop-driven WWII vintage fighters fast enough off the line to just make a standard take off run down the length of the deck? And how the hell did they launch 16 loaded B-25s off of the Hornet, in bad weather no less?
 
Prior to jets, take off speeds were much lower. The bad weather actually helped the Tokyo Raid B-25's as the ship pointed into the wind. Also, they were considerably lightened (guns removed, etc.,) for the mission.

Wikipedia does a good job of describing why a ski jump bow is used, and why WWII carriers didnt have catapults (battleships did for launching spotter seaplanes).

https://en.m.wikipedia.org/wiki/Aircraft_ski-jump
 
And how the hell did they launch 16 loaded B-25s off of the Hornet, in bad weather no less?
Well, let's see,, https://www.doolittleraider.com/first_joint_action.htm#_Toc510516197
The weather was bad in the vicinity of the carrier and most disturbing was the fact that a headwind of 24 knots could be expected all of the way to the target area.
...
This day the weather was very rough, the visibility good but the ceiling only 1000 feet. The Hornet was running into the wind at 27 knots. With the speed of the carrier, the speed of the wind and the blast of the first few B-25s running up, the propellers of the remaining ships were wind milling with the force of the combined wind. It normally requires two men to turn the propellers. Personnel moving about the deck had to do so on their hands and knees and had to clutch the deck plates to keep from being blown overboard.
...
Two sets of wheel markers had been placed on the deck. One set was at 400 feet from the bow of the carrier and the second set 450 feet from the bow. The first were intended for the first planes and when adequate space became available the second set was to be used. These wheel markers were composed of cork and sand which were to serve the purpose of preventing the wheels of the bombers from slipping on the wet deck during the engine run up. As it happened, only the first set were needed as the distance proved to be sufficient. Navy deck men were to follow each bomber with a set of wheel chocks, each of which had two long handles attached in order to prevent backslide that might be caused by the pitch of the ship

https://www.doolittleraider.com/first_joint_action.htm#_Toc510516193
The first take off runs were made with the airplane light. The distance used amounted to 800 feet but as new tricks were learned the distance decreased and the shortest take off run was that made by Lt. Don Smith in a measured 287 feet. A close observation was made on take off speeds and the lowest indicated air speed observed was 68 miles per hour. This is considered extremely slow as the normal take off speed of the B-25, at that time, was between 105 and 110 miles per hour. Normal take off was considered far less hazardous in view of the critical stall danger point during the short take off. Only one airplane was damaged during this practice and that occurred when 2nd Lt. Bates, a pilot who did not go on the raid, allowed his plane to slide back to the runway just after the take off as his wheels were being retracted.

Full load take offs were practiced by all pilots. This load included 2000 pounds of bombs, a full gasoline load, full crew of five with combat equipment, and full armament. All pilots qualified with full load take offs of approximately five to six hundred feet with a maximum ground wind of 12 miles per hour.
 
Yes,, thank you for this Hornet,, very cool post..
I thought they had to balance the mass of the aircraft and everything on / in it,,
with the force the catapult is set to launch them at
or they run the risk of damaging the front landing gear...
Has damage to a front gear ever occurred ??
Is it a serious concern ??
Or is it possible to just over build the front gear by enough of a margin so as to eradicate the concern....

Teddy
The launch bar/ hold down arrangement used these days is something of a new technique( relatively speaking). This attaches to the nose gear and showed up around the early 70's-late 60's. Prior to this a bridle was attached to the air frame. This was a throw back to the Korean war days when both prop driven and jet powered aircraft flew off the decks. Even the F-4 and F-8 used this arrangement. A point of interest, the British F-4's had and extending nose gear to get the nose up higher because of their shorter decks. This( the bridle) was a cumbersome affair. The launch bar came along about the time of the A-6,A-7. While the nose gears are quite robust it saved overall weight since the structure of the aircraft could be lightened. To answer your question, I'm sure there have been failures but I personally know of none. So, yea, you don't even think about it. Another thing to think about, With all the added thrust available these days, It's not like your launching dead weight. A fully loaded F-14D or A+ at 70+ thousand lbs had around 50,000 lbs of thrust if they used the burners. Which, by the way , are used less these days. Most shots are made at mil power(based on payload for the most part) Fuel is everything these days! Most -not all- aircraft kneel a bit these days. This runs the thrust line very close to the cat line getting every bit of energy into the shot. Prior to this , most aircraft sat nose high since they had to struggle into the air. If you watch video of older jets, they have a pretty smooth transition from the shot to flight and sort of just bank a bit and fly away. Newer air frames tend to shoot and snap up and away a bit more---it's all about the power! Fly by wire is a HUGE benefit too. So as you can see, the American carrier operation is always evolving and with decades of experience behind it. Those other guys are just learning the trade.
 
Ski ramp carriers also have a significant disadvantage: can't do simultaneous takeoff and recovery. I'd put the carrier I served on (the Ike) against a couple of ski jump carriers any day - especially given the rest of the carrier task force!
 
Ski ramp carriers also have a significant disadvantage: can't do simultaneous takeoff and recovery. I'd put the carrier I served on (the Ike) against a couple of ski jump carriers any day - especially given the rest of the carrier task force!

That's a couple of really important points. They suffer from range, deliverable payload,turn around time, just to name few. As for the task force--there is NO comparison. Madison Alum said they are just big targets. That's probably true--but they are the most heavily protected targets on the face of the Earth. Think about that next time you look at videos of the Baghdad airstrikes, claimed to be the most heavily defended air space on earth.It doesn't even compare!!Could the defenses be overwhelmed? It's possible but not likely. A nuke strike "might" take out the asset---at that point it doesn't matter.
 
That's a couple of really important points. They suffer from range, deliverable payload,turn around time, just to name few. As for the task force--there is NO comparison. Madison Alum said they are just big targets. That's probably true--but they are the most heavily protected targets on the face of the Earth. Think about that next time you look at videos of the Baghdad airstrikes, claimed to be the most heavily defended air space on earth.It doesn't even compare!!Could the defenses be overwhelmed? It's possible but not likely. A nuke strike "might" take out the asset---at that point it doesn't matter.

Like to see some footage of this. May be almost Star Wars-like :).
 
Not likely to work. If all the antimissle stuff on all the ships don't work, ask the escorting tin cans what their final mission is........
 
"That's a couple of really important points. They suffer from range, deliverable payload,turn around time, just to name few. As for the task force--there is NO comparison. Madison Alum said they are just big targets. That's probably true--but they are the most heavily protected targets on the face of the Earth. Think about that next time you look at videos of the Baghdad airstrikes, claimed to be the most heavily defended air space on earth.It doesn't even compare!!Could the defenses be overwhelmed? It's possible but not likely. A nuke strike "might" take out the asset---at that point it doesn't matter. "


Reseach Operation Crossroads Able shot, a demonstration of a atomic bomb vs. a naval fleet. Able Shot missed its intended target by nearly 500 yards (the USS Nevada) which was seriously damaged but did not sink, 5 ships were sunk ( a cruiser, 2 destroyers, and three transports), 14 ships tooks serious damage, all the ships had some fuel/aviation fuel on board for the test. Just using this example a nuclear warhead would need to get within 1000yds (probably less today) to have a chance of sinking a US carrier. Operation Crossroads consisted of Able (airburst) and Baker (underwater explosion that sank 10 ships in 1000yds).

Edit: forgot to include the quote from Hornetdriver, who as a military member is probably already familiar with Operation Crossroads. Personally my interest in the Operations Crossroads test and others, is that I work on a site where the plutonium was made and we are now cleaning up the mess from production.
 
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I believe the angled flight deck on the Kuznetsov class allows simultaneous launch and recovery.
 
.... I'd put the carrier I served on (the Ike) against a couple of ski jump carriers any day...

When were you aboard? I was in S-3 from Livorno '83 through the return to Pier 12 in '86
 
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