More Aircraft Carrier - Scenery Questions . .

[expat]

Have not tried this yet in FSX, but this is essentially the concept I am looking for - a fixed location, hard deck CV that is created as a scenery object and can be moved. With luck, I will manage to do it using the library object placement tool in ADE which is just aim and click once it is set up right. Otherwise I can manually edit the xml file.

Now, the question is, is there a way one may convert, e.g. Javier's hi res Nimitz v.2 - which essentially is an aircraft model, not a scenery bgl for purposes of FS - into a libary object and then place it anywhere one wishes?




<HR align=center width=600 SIZE=2>



<CENTER>FS2004 (ACOF) - FS2004 Scenery Objects </CENTER><CENTER>FS2004/FSX EZ Nimitz Library Update



</CENTER><CENTER>[ Download (http://www.flightsim.com/kdl.php?fid=120818) | View (http://www.flightsim.com/zview.php?cm=list&fid=120818) ] </CENTER>
Name: ez-nimup.zip (http://www.flightsim.com/kdl.php?fid=120818) Size: 871,391 Date: 02-25-2008 Downloads: 1,565
http://www.flightsim.com/n/ez-nimup.gif FS2004/FSX EZ Nimitz Library Update (with FSX hard deck). This is a scenery object library for use with Abacus EZ Scenery or Flight 1 Instant Scenery object placer software. It will allow you to place any of eight different Nimitz class carriers anywhere you choose with a hard landable deck as well as with a wake if you choose to depict it in motion. Model by Javier Fernandez. Hard deck by Mark Harper. By R. A. Baum.

[XLR8]

Hi there, I have also been working on getting the Nimitz to work . Anyway doodling about trying to place the Nimitz , I stumbled acroos away to use the Nimitz in scenery and for the most part works . I used inctant scenery 2 . I put the model and texure in the scenery file useing the program . Everything works, but for some reason I can't hook up to the shuttle to launch. I dosen't move around . Hope this helps .

[crashaz]

See here....
Library Creator XML

http://www.fsdeveloper.com/forum/downloads.php?do=file&id=10

You can take any MDL file and compile into a BGL library object.

Then you can use a tool to place said library object.:wavey:

[expat]

You can take any MDL file and compile into a BGL library object.

Sounds good. Does it create also an XML file along with the bgl?

Thanks for the help.

expat

[roger-wilco-66]

See here....
Library Creator XML

http://www.fsdeveloper.com/forum/downloads.php?do=file&id=10

You can take any MDL file and compile into a BGL library object.

Then you can use a tool to place said library object.:wavey:

Interesting thread.

What about functions that hide in gauges or effects or animations and such? Don't know if these will work after converting the mdl to a static bgl.
In SbuilderX one can place FSX mdls directly, but I have never tested that.

Cheers,
Mark

[crashaz]

Sounds good. Does it create also an XML file along with the bgl?

Thanks for the help.

expat
xml file... are we talking for placement location?

[Helldiver]

If a Carrier is fixed in position, forget about launching or recovering aircraft. The aircraft depends on the forward speed of the Carrier in order to do both. That's why Carriers are so fast,

[crashaz]

True HD... but in the FSX world it really doesn't matter.

[Helldiver]

Then it must be in "FSX world" you can fly with one wing. You need the Carriers speed or you'll be launched in the ocean or snap every wire on the deck.

[expat]

As usual, Helldiver, you are 100% spot on. I completely agree, and in fact, all one needs to do in FSX or FS9 is set the wind the wrong way 'round at say 21 or higher knots and you won't be able to land or takeoff on a carrier without crashing just like in the real world.

Remember though, in FS9 the only carrier you could land on with a hard deck was a fixed one, e.g. like the AS Big E. The moving carriers in FSX is of course far more realistic and I regard Lamont Clark's nifty AICarriers2 program to be one of the most vaulable add ons to FSX and use it all the time. Only reason I want to have some fixed boats as well is so I can do testing more easily and save flights to use later with the plane starting on the deck. I usually once launched will use the moving AI cv's and ALWAYS make sure they are turned into the wind before attempting to "catch a wire."

Regards,

expat

[Helldiver]

I fought like hell to get the developers of FSX to make the carriers move realstically. It was part of flyng off a deck. Now I'm told that a fixed position is OK since it's just "FSX world".

[mmann]

I fought like hell to get the developers of FSX to make the carriers move realstically. It was part of flyng off a deck. Now I'm told that a fixed position is OK since it's just "FSX world".

FSX, as real as it gets right?

Mike Mann

[michael davies]

Hate to burst anyones bubble but all Nimitz and probably the previous fossil fueled carriers can launch aircraft in still air, you don't get as much payload or range but the steam cats are perfectly capable of launching aircraft at their medium weights with no wind across the deck. This was stipulated after experience in WWII where carriers where crippled dead in the water and the air wing could not take off, its a damage limitation exercise, you may loose the boat but you still save and awful lot of your air wing.

Landing is another story but launching, is possible, I've some shots somewhere, will try and dig out if time permits.

Best

Michael

[Helldiver]

Mike, since I got no experence with oil burners, or crooked decks or steam catapults, I only refer to straight deck Essex class carriers. The good kind.
It was quite a wallop when we got launched by hydraulics. What a kick in the behind it must be to be hit with a steam catapult. Make sure you went to the bathroom first and if you suffer from the "Hershey squirts", - forget about it.
Like you say, they may be able to launch them, but recovery on a still carrier presents a problem. All they can do is to pray for a hell of a head wind or head for the nearest land based airport.

[michael davies]

HD see attached, an Essex, stationary but not straight deck so the cats are steam which gave a much bigger punch. This being CV-19 USS Hancock in 1961 and granted a Spad is no where near a Whale or Crusader to launch at zero across deck wind.

BTW what did the Essex class burn ?, I always thought it was oil, surely it wasnt coal, I know some RN / US battleships burned coal but I think most had been converted to oil by WWII, but I do know what you mean by oil burners, ie Forrestal onwards.

As you say, I seriously doubt a hydraulic cat has the power to static launch an aircraft, there just isnt the expansion you get with steam.

Best

Michael


Mike, since I got no experence with oil burners, or crooked decks or steam catapults, I only refer to straight deck Essex class carriers. The good kind.
It was quite a wallop when we got launched by hydraulics. What a kick in the behind it must be to be hit with a steam catapult. Make sure you went to the bathroom first and if you suffer from the "Hershey squirts", - forget about it.
Like you say, they may be able to launch them, but recovery on a still carrier presents a problem. All they can do is to pray for a hell of a head wind or head for the nearest land based airport.

[XLR8]

I have the freeware Nimitz working in free flight now . Its stationary,and everything works,including the cat,arestor wires,elevator, steam,the vehicles move around . I was having problems launching aircraft (would not arm/disarm) . The problem was I has to put the launch arm in the right spot .

I will say its freaking fun to cat and trap .

[skyblazer3]

Congrats! Glad to hear this worked out. How did you do it?

[XLR8]

Congrats! Glad to hear this worked out. How did you do it?


I pretty much used Instant scenery library maker to put it in the scenery file. Then placed it in the area I wanted . The first time I had no textures,but that was easy to fix . I will post some screens .

[XLR8]

Heres some screens of the Nimitz .The first couple are of the elevator with the T-45 waiting for it to rise . One of the T-45 on it .If you look close there is a pic of that little truck that passed by while waiting . The 3 of the cockpit are of a trap,note the speed . Last is after I stopped after the cat .

http://i217.photobucket.com/albums/cc280/hellcat77/2010-8-11_17-28-59-545.jpg

http://i217.photobucket.com/albums/cc280/hellcat77/2010-8-11_17-29-51-615.jpg

http://i217.photobucket.com/albums/cc280/hellcat77/2010-8-11_17-30-46-656.jpg

http://i217.photobucket.com/albums/cc280/hellcat77/2010-8-11_17-32-29-146.jpg

http://i217.photobucket.com/albums/cc280/hellcat77/2010-8-11_17-32-29-626.jpg

http://i217.photobucket.com/albums/cc280/hellcat77/2010-8-11_17-32-31-6.jpg

http://i217.photobucket.com/albums/cc280/hellcat77/2010-8-11_17-32-34-86.jpg

[crashaz]

Hehehe... always recognize the Koolau mountain range. :d

[Helldiver]

Mike, we burned No 2 crude oil, but I think that it was then changed to electric power for propulsion. I'm not an expert in this matter since I was a Airdale and did not fraternize with ships company. But I have seen the hoses dripping when we refueled at sea and it was a black, gookey looking stuff and it smelled bad.

[expat]

Dumb question time (again): before the nuke era, were the Forrestal, Midway and Essex class carriers diesal-electric powered - which seems to be Helldiver's recollection on the Leyte? This seems close to the set up with modern diesal locomotives, i.e. diesal engine turns generator powering traction motors.

At the same time, I have also seen "steam turbine" power mentioned, which I expect is not the orginal "steam engine" propulsion used, for example, at the turn of the previous century powering the Great White Fleet ships etc, which would be analogous to the steam locomotive engine using boilers and steam pistons etc.

[Helldiver]

I may be way off base here but I don't think they had Deisel engines. Rather they generated steam that turned a turbine that powered the electric generators which ran the electric motors.
Like I say, I was a bit divorced from ships company. The air group is only guests of ships company and never get involved. We miss out on fun things like chipping paint and mess cooking.

[ARDVARK]

HellDiver your posts are excellent and insightful, were you a Pilot in WW2?

[michael davies]

As far as I can ascertain, all US carriers use steam turbines, these turbines are then direct connected to the prop shafts. It'd be some motor that could produce 37,000 HP, its hard to do that today with modern 3phase synronous motors but back in the 40's, it'd be a DC motor and thats one very big DC motor ! LOL, for a start it'd be too big and way to heavy, turbine is lighter and smaller by a vast margin and in a warship, size and weight are critical. Steam can produce vast amounts of power so it'd be crazy to change its format more than you had to before you had an output, ie steam/mechanical or steam/mechanincal/electric/mechanical, you just loose too much energy in each conversion.

So no, there are no steam/nuke-turbine-generator-electric motor propelled US carriers. There are ancillary turbines with generators for other ships supplies, but not propulsion. Traditionally power plants are split into main propulsion and ancillaries and that still holds true in todays modern vessels.

I will keep checking though, as I have a niggle that an electric motor was in the drive train somewhere and was maybe used for minimum steerage or maneuvering power, as y'all full well know, the Essex class could go almost as fast backwards as they could forwards, that'd be from the main turbines, but running turbines in brown water applications would be costly so its plausabe that electric was used in and near port.

Anyway, some turbine data for you.

Essex class, four turbines at 37,000 SHP each

Midway class, four turbines at 53,000 SHP each

Forrestal class, four turbines at 65,000 SHP each

Nimitz class, four turbines at 65,000 SHP each

What is a steam turbine ?, well its like a jet engine in reverse, though the blades are much shorter and a much larger piece of equipment, you'd not want one strapped to your wing LOL, typically their weight is in tons, lots of them, several hundred on large turbines in electricity generating stations.

Steam is generated by large boilers and then passed through the turbine, the output shaft is then connected to the prop shaft. Steam turbines are also the favored power plant for large merchant tanker vessels, typically VLCC and ULCC super tankers, the oil used here is cheap thick stuff so requires heating all the time to make it fluid, not only to burn in the boilers but to transfer from the vessel.

Attached a few pictures of a single reduction HP/LP turbine use in a marine application, pictures of naval installations are as you might image 'not easy to procure' so for this tutorial I'll use a merchant application, but the theory is the same and probably looks pretty much the same.The images are from the worlds largest super tanker the M/V Batillus 275,000 GRT, however the layout and set up is pretty similar for US carriers or other steam turbine powered vessels, though the Batillus is single reduction, Essex class is double reduction. On the Batillus each turbine is rated at 32,000SHP so pretty close to an Essex sized turbine.

There are two shafts connected to the main flywheel, each shaft houses two turbines, though technically the whole arrangement is called a turbine even though theres two 'actual' turbines inside. The smallest turbine is the High Pressure (HP) one, steam enters here at very high pressure, on the Essex class at 565psi and 850F, this passes through the blade sand makes them rotate, the exhaust steam still has an awful lot of energy left so it is trunked across the turbine (see the connecting tube) and into the Low Pressure (LP) turbine where more work is extracted from it, due to the LP side steam being much cooler and lower pressure, the blades are much larger to get as much energy from the steam. The large bell housing affair at the back end of the LP turbine is the exhaust, the prop shaft is connected to the large gear in the center of the box.

There does appear to be what looks like a radially fitted piston engine on the end of the LP shaft, this could be the reverse engine or some sort of pump off the LP shaft, though most pumps and ancillaries are fed from other parts of the vessel, so I suspect on first inspection that this is the reverse engine, but for a vessel this size I'd have expected something larger, the Essex class had an additional reverse turbine added to the other end of the LP shaft. I dont ahve the full spec for the Batillus so cannot be 100% sure where reverse is fed into the drive train.

Hope thats of some interest to someone LOL.

Best

Michael

Addendum, it would appear that turbo electric was used on the previous class of carriers, ie the Lexington class, this is new information to me and a class I'm not really up to speed on so will need to dig out more info, an interesting concept for such a large vessel and I suspect rather than one motor per shaft theres going to be quite a few to keep the size down. This class being derived from a battle cruiser hull and as such this form of propulsion seemed to be in vogue in the 20s as its also fitted to USS New Mexico and the Tennessee and Colorado class Battleships, now information on those I do have :).

Ok here we go, Tennessee class uses Turbo electric drive, featuring four electric motors, each motor is three phase, makes sense to keep size and weight down, but quite rare in the 20's as sycronous motors were not the norm. Supply to the motors is 6,800 volts, thats an awful lot of electricity LOL, each rated at 4,300Kw each which is equivalent to about 6,800SHP. Initial reading shows Lexington to have eight motors with a total of 212,000SHP, thats 26,000SHP per motor or 16,450kw / 16.5Mw now that is one huge motor by anyones standards LOL, and theres eight of them !.

[expat]

I don't think they had Deisel engines. Rather they generated steam that turned a turbine that powered the electric generators which ran the electric motors.


That make sense. Though this suggests that the turbines turned the propellors directly, via reduction gear.



Displacement: 27,100t standard, 36,380t full Dimensions: 872’x93’(147’5” flight deck)x28’5” Machinery: Steam-reduction: 8 Babcock & Wilcox 565PSI boilers, 4 Westinghouse geared steam turbines, 4 shafts w/non-CP 4-bladed props Max speed: 33kts Range: 20,000NM @ 15kts Complement: 2600



http://en.wikipedia.org/wiki/Template:Essex_class_aircraft_carrier_propulsion

http://webcache.googleusercontent.com/search?q=cache:JiBS98MnU4sJ:www.harpoondatabases.c om/encyclopedia/Entry1937.aspx+essex+class+steam+turbine+reduction&cd=7&hl=en&ct=clnk&gl=uk

[vora]

Very interesting indeed, thank you.
I agree that the reverse drive is most probably propelled by the radial piston engine at the LP section. In pic#2 you see that both turbine shafts are connected to the gear shafts by couplings (LP is decoupled). So for reverse drive they probably decouple both shafts, let the rotation of the gears die down and use the piston engine in reverse direction.

[michael davies]

Yup, that'd make sense, note also the two large discs on each shaft opposite the two turbines, one presumes they will be brake discs to stop the shafts turning before reverse is selected and once the main turbines are disconnected.

Best

Michael


Very interesting indeed, thank you.
I agree that the reverse drive is most probably propelled by the radial piston engine at the LP section. In pic#2 you see that both turbine shafts are connected to the gear shafts by couplings (LP is decoupled). So for reverse drive they probably decouple both shafts, let the rotation of the gears die down and use the piston engine in reverse direction.

[vora]

Indeed, brake discs and brake shoes of gargantuan dimensions... I just love such pictures :applause:

[michael davies]

You'll like these then, OT but shows a 2500T crane being winched sideways off a 30,000GRT vessel across bridging flaps and onto the quay, and an overall view from further back and the other side showing the seaside legs just coming over.

Best

Michael


Indeed, brake discs and brake shoes of gargantuan dimensions... I just love such pictures :applause:

[dswo]

The Nimitz class generates steam with an onboard nuclear reactor.

[vora]

:kilroy: Was this monster crane installed temporarily on that vessel? What for?

You know, no matter if you love planes or vehicles or something, it's the naval sector where the huge forces are handled with. A Nimitz with ca. 100,000 t displacement at a speed of 30 kn... just think of the kinetic energy of this! And the technology to control this comes directly out of an engineer's wet dream.

Guys love BIG forces, some the chaotic way (blow things up), some the more controlled way (turn a house-size wrench).
At the end of the day it comes down to this: :d
15266

[michael davies]

The vessel is a converted tanker, she has had most of the oil holds cut down to near water level, some of these vessels are semi submersible to allow floating loads to be loaded, but this one isn't. The cranes are made fully built in China, loaded onto the vessel and shipped all around the world to the terminal where they are destined, where upon they are unloaded complete and onto the quay.

Yup, have to confess to having a love or large dynamics and there forces, be it nautical or rail.

Best

Michael



:kilroy: Was this monster crane installed temporarily on that vessel? What for?

You know, no matter if you love planes or vehicles or something, it's the naval sector where the huge forces are handled with. A Nimitz with ca. 100,000 t displacement at a speed of 30 kn... just think of the kinetic energy of this! And the technology to control this comes directly out of an engineer's wet dream.

Guys love BIG forces, some the chaotic way (blow things up), some the more controlled way (turn a house-size wrench).
At the end of the day it comes down to this: :d
15266

[Helldiver]

Your very right, Mike. I don't know how electricity got in there but it's been 64 years ago and the mind does gets confused. I did go down to visit the shaft log. The shafts were 36 inches in diameter and were suprisingly held by wooden Lignam Vitae bearings.

[michael davies]

HD, the Essex as does quiet a few other warships, have very long prop shafts, the engine room being almost midships, modern ships have the engine room as far back as possible and thus much shorter prop shafts.

The low RPM does of course mean that less 'technical' bearings can be used LOL, and during war time many specialized metals that normally make up bearings would be in short supply. Interesting info there, must look up Lignam Vitae LOL, being a youngster nearly everything I know is needle or roller bearing :).

As an aside, large steam turbines don't actually have bearings in the normal sense, they float on a bed of oil, when cold they are highly pressurized to 'jack' them up, as they rotate the oil is dispersed evenly around the bearing and the shaft becomes naturally centered, not sure about Marine turbines but the Electricity ones we have here in many UK power stations have that bearing, due to the size of these turbines, pressures and temps they take nearly a week to get up to speed and temperature before they are put on line and loaded up, and then they run for months non stop. One of the down sides of there size is that the shafts bend when cold, thus when running up they wobble and as they are slowly heated they become centrifugally straight, very clever technology and quite frankly kind of scary, big bits of metal do very strange things when heated and cooled LOL.

I suspect marine turbines are much more robust and looking at the Batillus arrangement the gear box shafts look encased in roller bearings, but the turbine shafts have semi circular shells, probably oil pressure assisted, much as you'd expect due to the higher RPM involved.

Best

Michael

[Helldiver]

The lignam vitae have a natural lubricity to them. Perhaps they vacuum impregnate them with additional oil. They were segmented, about 6 or 8 inches long and six inches deep. It's the hardest wood known and they told us that it would outlast most mechanical bearings. I don't remember how many bearing stations there were. I know the engine room as being very clean, well lighted and hotter than hell. This is in the days when air conditioning wasn't used by the services. It was a time for men to be men and woman to be double breasted.
I would like to know more about the running gear about an Essex class carrier. Got any blue hats out there? Like what did they use as a packing gland to withstand so much pressure? How do the maintain extra steam when the ship goes from being still to flank speed?