FSDreamTeam forum
General Category => Unofficial F/A-18 Acceleration Pack board => Topic started by: Voodoo on November 11, 2009, 08:38:45 pm
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Javier has released an updated version of his Carrier pack. The description says he's added, amongst other things, steam catapult effects. Yea!
http://www.flightsim.com/kdl.php?fid=140822
P.S. Take care, it's a 124mb download!
Here's the description:
"FSX Acceleration USS Nimitz and USS Eisenhower, v2.0. New version of AI moving aircraft carriers USS Nimitz and USS Eisenhower for FSX Acceleration. New features include catapult steam, new animations and underway replenishment (oiler ship model inluded). Features a working elevator, four cables and catapults. Includes multiple deck configurations. Aircraft on the deck include SH-60, E-2C, T-45 and four variants of F/A-18 of CVW7 and CVW11. Recommended usage with Lamont Clark's AIcarriers2. By Javier Fernandez."
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Thanks for the heads up! It looks great from other people's screenshots too :).
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Here's a couple of stills.
(the effect unfortunately only triggers once per cat, but it's verra nice anyway!)
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Much thanks for posting Voodoo... Going to install tonite and mess around with it. The steam cat shots look great.
Also, good and bad news. The VRS Superbug is going for 50 bucks. However, it wont be ready til late January at the earliest. Didnt mean to ruin anybody's Veterans Day.
Check out the screen shots though, can you imagine the Superbug with this new carrier? Damn.
http://www.vrsimulations.com/forums/phpBB3/viewtopic.php?f=1&t=2071
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Wow that looks awesome.
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Only once per cat per flight? That sounds odd to me. Wonder why...
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Yeah, I ran into exactly the same problem when I did the steam effects for the default carrier, Orion.
If the steam effect is given a lifetime, once the effect has expired, it just doesn't trigger again. At least not on the same attachpoint.
On the other hand if you make the effect run continuously, it triggers, stays on until you try triggering it again at which point the effect stops, and immediately does trigger again.
I just don't know enough about the effects engine to know why it works like this. Be nice if someone could explain it though.
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only works in single p;layer, correct?
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Yeah, I ran into exactly the same problem when I did the steam effects for the default carrier, Orion.
If the steam effect is given a lifetime, once the effect has expired, it just doesn't trigger again. At least not on the same attachpoint.
On the other hand if you make the effect run continuously, it triggers, stays on until you try triggering it again at which point the effect stops, and immediately does trigger again.
I just don't know enough about the effects engine to know why it works like this. Be nice if someone could explain it though.
I wonder how the default effects avoid that behaviour... Maybe someone should go study them :P.
only works in single p;layer, correct?
It only works as AI :P. You need to use the SDK or 3rd party software if you want to be able to use it in any flight :P.
I'm currently working on a mission to get the carrier working in multiplayer (see here: http://www.fsdreamteam.com/forum/index.php?topic=2224), and I've only got a few more things to do and it'll be released. I'd expect it to be ready in the next month or so ;).
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I gotta give this a try. It looks great and Im hoping that the Flight1 UT2 product doesnt interfear with the ships. I know it does interfear with the ai.carriers1 package. Thanks for the dwnload Voodoo. ;D
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Thanks for the link VooDoo
I finally got it to work yesterday
and it works with the Windows 7 operating system too ;D
Took me three tries to land your Herk on the deck though,,Lol, ;)
Nice to have a carrier moving,,instead of stationary
Big difference
Thanks again for the referral
Randy
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Hey Fellers...
Just uploaded and was trapping with the new HUD and realized that these new carriers are slower than the default Acceleration Carriers. The only reason I make note of this is that, if you are a By-The-Book Navy Pattern flyer (as I try to be), then using this carrier is much better in that respect. From my analysis the AC is steaming at 35 kts and takes on average :26 from 3/4 final (.7nm) to touchdown. Whereas Javier's carrier steams at 26 kts and takes on average :21. Now, this is still about 3-4 secs slower than real life (18 secs), but at least its closer to realistic.
If you want to compare, I had a fun game of carrier chicken, then lined them up side-by-side to give people a visual of the speed difference.
Enjoy.
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Sludge, thanks for info - those graphics are a bit TOO DARK! for me. Get a bit of daylight. Works wonders. ;D
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Yeah, I might come back to the light someday?!
Do you know how to modify the carrier speeds? Would love it if I could tinker with their speed to about 15-20 kts and see what happens then?
Anybody... Bueller... Bueller....
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Sludge, Sorry I have no idea how to modify carrier speed. What Wind are you using?
One thought - you could make the carrier steam downwind with the wind coming back up the angle a bit to nullify some forward carrier speed? Sum (of all fears) would be whatever it is? Yeah I'll stop the jokes.
SHOW ME THE MONEY! It is my (Bueller's) day off. ;D
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Take a look, for example, in your "SimObjects/Boats/veh_carrier01_high_detail_sm" folder. (This is the default AccPack carrier.)
There's a file called SIM.CFG which contains the speed parameters in the [DesignSpec] section.
Default speed is 50. Try something like 35-40 to slow her down a bit.
I've no idea what the units are, but if you want your carrier to run like a power boat try: max_speed_mph = 200. You'd be hard pushed to keep up with her in a Hornet...LOL...but you get the idea!
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Thanks Voodoo, I'd like to see a video of that '200' power boat setting. :o ;D Beuhler? Anyone?
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Haha, you'd have to use afterburners to land on this thing at 200, and no need for tailhook - you can land like a helicopter, no need for angled deck either... just one helipad above the nuclear reactor ;D
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Haha, you'd have to use afterburners to land on this thing at 200, and no need for tailhook - you can land like a helicopter, no need for angled deck either... just one helipad above the nuclear reactor ;D
That would ba a video worth watching ;D ;D
Ya would have to replace the landing gear with Talons to keep the bug on the deck at that speed ;)
Randy
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So make a FUNNY video? No? ;D PuhLease.
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Thanks fellers...
Yeah, late last night, I finally did that stuff and it worked. I even got to the point of slowing down the accel carrier to the point where the steam cats look like the four attachpoints with some smoke puffs coming out, so thats a bit too slow. Might just have to drop them about 10 mph and settle for a balance between look and realism. I think setting a max speed of 30 gets it down to Javier's carriers, round 25 kts. Good enough for me, with 0-5 kts of headwind.
Different tastes
Later
Sludge
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If you like, Sludge, I can work you a set of steam effects that will look fine at slower speeds? (or at least what I would do is check out which parameters to alter in the effects files so you can alter them to suit yourself at any time).
I'll go and have a look tonight and see what steam settings work ok at max_speed=30.
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Voodoo...
Sure that would be cool. Only if you have nothing else on your plate, though, and you dont mind. Its a fun visual to have.
Since we are kinda on topic, has there been any progress with Javier's carriers, regarding the one time only steam shots?! Or is that something that would be tough to make look like the acceleration carrier? As I dont mind the steam coming out from the cats, once youve used them. Even if they never stop.
Anyway, thanks for the offer and let me know how it progresses!
Later
Sludge
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No worries, it's great fun tinkering with these things! :D
Re. Javier's carriers...I think that he has done the hard work of putting in the attachpoints so it should now be very possible to alter his effects to make them work like the default carrier. I shall have a look at that after I test out some steam variations for the default boat.
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No worries, it's great fun tinkering with these things! :D
Re. Javier's carriers...I think that he has done the hard work of putting in the attachpoints so it should now be very possible to alter his effects to make them work like the default carrier. I shall have a look at that after I test out some steam variations for the default boat.
VooDoo ,,
I have as yet to look at those effects files,,so if this suggestion is out there, no laughing,, is it possible to put a time limit on that effect of let say a minute or so then have the effect re-set?
Randy
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Voodoo...
Thanks much, man. I like the Javier's carriers better as a whole (the details, the flight deck people, the planes and vehicles), but like the steam of the default, so if you were able to combine the two that would rule!
All in all, this fall has seen some of the best progress/work done on the acceleration hornet and carriers in a long time!! Now can you imagine that once the SuperBug gets done (seen the detail on those guys?!), how immersive the experience will be. I think when its all said and done by February, there will be some happy flight simmers out there, especially us military guys who have enjoyed the Hornet and Accel carrier since it came out.
Thanks again, amigo!!
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Anyone know how to get a the carrier to move up and down with the waves in FSX, to simulate a pitching deck scenario?
I understand this could make the IFOLS information incorrect since the IFOLS is not stabilized in FSX, but I saw this video of a tugboat in FSX and it is definitely pitching up and down so I assume it is possible, I just don't know how to do it. Here is the video http://www.metacafe.com/watch/1204166/fsx_smit_rotterdam_heavy_tug/
Thought this would make for some challenging approaches. 8)
Also, on a separate note, anyone know how to add a tanker flight to a mission. I use the TogGun sim daytraps mission and would like to add a tanker AI using the KC-135 I have, flying near the carrier for some "trick and treat" ops. Has anyone added a AI flightplan to a mission before? Any help here would be great.
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There is definately pitch as in the Helicopter TRG mission involves a pitching deck.
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OK, peepses, here is the steam effect for Javier's carriers. It works in exactly the same fashion as the steam effect for the default carrier (i.e. the effect triggers when you launch from the cat, and basically keeps going).
Just drop the attached file into your main Effects folder, and that's all that's required!
Please remember to to take a backup copy of the original file before you replace it.
(N.B. if any of you are using the "fx_catapult.fx" effect file for Javier's carriers that I posted on Voodoo's Hangar, please rename that, or delete it. You won't need it anymore, but Javier has left that attachpoint in his models so it will look weird if you continue to try and use it!)
@Intrepid,
Yo Randy, your idea is good, but that's what Javier himself tried to do with his original effect, and for some reason, if the effect is allowed to expire, it just don't seem to trigger again!
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Thanks Voodoo...
Downloaded and will try out tonite and get back to ya with results.
Later
Sludge
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I'll try as well. Thanks
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Cheers, Sludge (and Wily).
If this works ok for you, Sludge, I may not bother to rework the default carrier effect for slower speeds, unless you still have a desire for it. If so, just shout.
All the best,
- Voodoo
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Voodoo...
Much thanks to you. Yeah, that mod worked perfectly, dont even worry about the default Ill just use this one.
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Anyone know how to get a the carrier to move up and down with the waves in FSX, to simulate a pitching deck scenario?
Since you ask..... yes, it is possible. Here's a clip of a video I'm working on:
And, believe it or not, the ball actually IS stabilized. :o I know, I was shocked too!
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Anyone know how to get a the carrier to move up and down with the waves in FSX, to simulate a pitching deck scenario?
Since you ask..... yes, it is possible. Here's a clip of a video I'm working on:
And, believe it or not, the ball actually IS stabilized. :o I know, I was shocked too!
PLEASE! Share how to do this or a download, there was a smile on my face as soon as I saw the first F/A-18 coming in to the end of the video!
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Microbrewst, bravo! :o
That is exactly what I am talking about. Great video by the way, very impressive!
I know several of us would like to know how you got the CV to pitch like that, is it a sim.cfg change. I would love to be able to fly pitching deck, especially if the ball is stablized, which is good to hear.
Thanks for sharing!
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Microbrewst, Agree with others - great video. Nicely done. Great to know that the ball is stabilised. If that is the case then having the option of a pitching deck would be a nice edition to FSX for sure.
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Cant wait til this mod is shared with the fellas...
Looks really cool, and even more immersive! If thats possible.
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These guys CANUCKS need the carrier pack for some Carrier Landings eh: ::)
http://www.aircombatzone.com/2007site/corphome.html#video
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These guys CANUCKS need the carrier pack for some Carrier Landings eh: ::)
http://www.aircombatzone.com/2007site/corphome.html#video
I have been there, Wicked experience, 8),I agree, the carrier pack would be a great addition
Randy
P.S. I am happy about the amount of activity on this site lately
thumbs up to all involved with this UPGRADE
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Good post Spaz...
Thats almost to Naval Aviation museum quality. Have you been to the flight sims there? They took old Tomcat and Hornet cockpits and made some hella sims out there! Alot of fun and realistic!
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Sludge I'm in OZ (Australia) not likely to get to Canada anytime soon. ???
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Am I right in saying that the reason the ball is stabilised is because the boat is rocking around the midship section close to the meatball where there is relatively little motion as opposed to the bow and the stern which are moving a lot in relation to sea level?
just curious to know if i am reading this right?
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sonofabeech, I gather you refer to the real world as well as the flightsim? Can't comment how any mirror stabiisation is achieved in the flightsim - I have no idea. In real world what you are saying helps minimise the mirror stabilisation problem by having the mirror (almost) at the centre of the front and back going up and down, however.... Several of the online PDFs mentioned in related threads deal with this issue, I'll refer to them now and get back to an answer later. "Heave" is one aspect possibly not mentioned about ship movement including 'hogging' and 'sagging'. Heave is the up and down vertical motion as the carrier traverses swell for example, whilst the latter is caused by the metal bending in the sea state. Remember that a carrier is LONG with the effects you have described at front and back causing other secondary effects. One aspect perhaps forgotten is that it might seem that the movement of the ship is regular, when likely every now and then it is not; in an unanticipated way it will stop moving in a regular cycle to reverse what it is doing - SUDDENLY - just to make carrier landings that much more exciting....
Not to forget that the ship is rolling in the sea state that in itself is less 'predictable'. Imagine now how the glideslope is projected some distance from the ship in an ever expanding cone of light. Any movement at the source is exaggerated the further one is from that source. Mirror stabilisation helps minimise the 'far reaching effects' of any ship movement. ;D As Sludge says: 'later'.
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One particular online PDF (available from many websites) has a lot of explanatory information amongst a lot of info irrelevant to answering the question above but bear with me to read the text to get an idea of the 'carrier landing problem'. Other specific PDFs such as the LSO NATOPS MANUAL give more specific info with diagrams. However I'll post the material below because I think it is useful... [GS=GlideSlope]
REVIEW OF THE CARRIER APPROACH CRITERIA FOR CARRIER-BASED AIRCRAFT PHASE I; FINAL REPORT 2002
http://www.robertheffley.com/docs/HQs/NAVAIR_2002_71.pdf (2.8Mb)
Quotes below from pages 43-65 approximately:
"Stabilization
FLOLS stabilization is provided from signals from the ship’s stable element to provide a stabilized GS with respect to the horizon, under moving deck conditions. Two modes of stabilization are available:
a) Line Stabilization: Used as a backup, this mode stabilizes the FLOLS display for pitch and roll motions of the ship to maintain a predetermined line in space at the intersection of the FLOLS light plane and the true vertical plane through the centerline of the angled deck. This stabilizes GS without compensation for ship’s heave.
b) Inertial Stabilization: The inertial stabilization mode is the primary mode of operation for the FLOLS. This mode adds compensation for ship's heave to the line stabilization."
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THE CARRIER LANDING
The task of landing aircraft at sea on the pitching decks of CV’s has long been recognized as being among the most difficult of aviation's tasks. The environment is certainly among the most demanding encountered anywhere. Advances in technology, reflected in the engines, airframes, control systems, and displays have transformed the hazards. The operational challenge for the technologist is to further improve the safety of landing at sea while increasing the likelihood of successful arrestment on the first attempt.
Designing for CVS entails far more than merely landing on a small dynamic runway at sea.... Several engineering constraints dominate the landing problem. The aircraft must land: 1) in the desired spot in order to engage a CDP, 2) with no lateral drift to stay within the landing area during the run-out, 3) in the proper attitude to set the hook properly in the wires, 4) at an appropriate speed so as to not overstress the arresting gear engine, and 5) within the sink rate limitations of the landing gear. Additionally, the LSO wants to see the aircraft cross the fantail of the ship with a specified margin above the round-down to confidently avoid hitting the ramp ("H/R clearance"). Finally, the combination of flight condition and power response has to be such that full power can be rapidly achieved for successful waveoff or bolter.
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Hook touchdown amidst the wires does not guarantee successful arrestment. Although the hook is heavy, the violence of impacting the deck at such speeds can cause the hook to bounce off of the deck and over any wires. Hydraulic or pneumatic actuators or dampers may resist this phenomenon, but the aircraft must still be close to the appropriate touchdown attitude for them to be effective.
"Hook-skip bolters" commonly result from a last-second nose-down correction intended to save an "over-powered at the ramp" condition. This “play” for the deck succeeds in guiding the aircraft into the wires, but lowers the attitude such that inadequate pressure is applied to the hook-point to keep it low to the deck.
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WOD is the vector addition of the natural wind, and the ship's forward velocity. The WOD is commonly between 25 and 30 kt, thereby significantly lowering the closure rate an equal amount. This represents a substantial decrease from the kinetic energy of the aircraft in the inertial reference frame.
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The modern approach to an angled-deck carrier entails a stabilized GS at constant speed from no less than ½ mile aft of the ship to arrestment. The stabilized GS ensures satisfaction of the touchdown, drift, and H/R constraints.
Flying at a specified approach AOA (in lieu of speed) ensures that the aircraft is in the proper attitude for CDP engagement, and that the approach speed and sink rate are within bounds. Flying a specified approach AOA also provides the pilot and LSO with a consistent sight picture.
Consequently, every aircraft specific approach looks identical, regardless of its weight or external loading. From the LSO platform, or from the cockpit, the picture looks the same day-to-day, regardless of the other variables. Finally, the stabilized approach maintains a moderate nominal throttle setting, permitting fairly rapid response to MIL power in the event of either waveoff or bolter.
The landing task may be made more challenging by the presence of the ship's burble. The source of the burble is the interference of the structure of the ship with the relative wind, and its influence is felt mainly in the last half mile of the approach to the ship. The ship structures that contribute to burble are primarily the island, the bow of the flight deck, and the corner formed between the end of the angle deck and the rest of the flight deck (the "crotch"). Burble consists of random, periodic, and steady components. The random component is chiefly caused by turbulence in the lee of the ship's island structure. This turbulence is worse when WOD are predominantly aligned with the ship's centerline (axial winds), which place turbulence in the lee of the ship's island structure at the in-close position of approaching aircraft. The periodic component of burble is associated, in part, with the cyclic pitching motion of the ship. The steady components of burble consist of a reduction in the steady wind and a predominant upwash aft of the ship that are functions of the magnitude of the WOD, and the range from the ship....
Burble is not considered a major factor in routine shipboard operations, but rather an ever-present feature of the task. Pilots adapt quickly to each ship, subconsciously anticipating the aircraft's reaction to their nominal experience. In rare cases, such as naturally gusting surface winds or large, rapid ship motion, the burble can have a dramatic effect on the pilot's ability to fly a precise approach. Safety of flight can quickly be compromised, which will result in either a higher accident rate or lower boarding rate.
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PILOT PERSPECTIVE
The pilot is the most unpredictable component of the shipboard landing system. "Fatigue" means something completely different to the aircraft than it does for the pilot. The aircraft flies the same on its 5th shipboard landing as it does 200 later. The aircraft does not care whether the sun is up or down. All of these issues, among others, profoundly affect pilot performance, and consequently system performance. Aircraft features and attributes can limit the variability of the performance of the pilot. This section addresses these topics beginning with the pilot as a multivariable sensor and feedback control system.
The human part of this pilot-aircraft system is limited in the ability to control multivariable problems. A human with sufficient control authority can control one dynamic variable very precisely, two variables precisely, three variables passably. The pilot’s performance deteriorates severely trying to simultaneously control more than three. Fortunately, the multiple constraints of a CV landing are satisfied by the pilot's control of just three variables – GS, lineup, and AOA. Pilot performance is affected by the allowable tolerance of the accepted deviations, the dynamics of the particular variable, the responsiveness of the aircraft to control inputs, the environmental conditions, and the quality of the information used to determine GS, lineup, and AOA error. It is important to note that tactical Naval Aviators, in the context of CV landings, speak interchangeably about speed and AOA. Though they are reading AOA in their indicators, they refer to themselves as either "fast" or "slow"....
SENSORY INFORMATION
Since the pilot is trying to simultaneously close the loop on three states, the quality of the information provided is vital. GS is provided by the FLOLS that is stabilized in pitch and roll to compensate for pitch and roll movements of the ship. As every aircraft has a different H/E length, the lens is adjusted for each aircraft model, such that if the pilot maintains the central light in the lens aligned with the reference lights ("datum"), the hook will touchdown midway between the second and third CDP. Because the GS information is displayed in a radial fan of light cells, the resolution of the vertical displacement from GS improves with the inverse of distance from the ship.
The centerline stripe and lights provide lineup information, as do the drop lights. AOA is provided internal to the cockpit in a variety of displays. These are the primary sources for the three control states.
It is significant to note that GS, lineup, and AOA in and of themselves only provide displacement error. The best closed-loop performance is achieved feeding back error rates rather than displacement errors themselves. Error rates for GS and lineup can only be assessed by monitoring the change in the error over time. For example, a glance at the lens will identify one's location relative to the GS, but will not identify whether the error is increasing or decreasing. Periodic sampling over some finite time is required to discern whether the GS is improving. The same is true for the lineup. In darkness, LSOs contribute significantly in that they can usually detect developing error rates before the pilot.
Heads-Up Displays (HUD’s), such as that found in F-14D and all F/A-18 models have dramatically transformed the landing problem. First, an Inertial Navigation System (INS)-driven velocity vector precisely displays the projected flightpath of the aircraft. Ashore, the velocity vector permits a pilot to superimpose the symbology directly on the intended point of landing and achieve very precise results. At sea, since the ship is typically moving relative to the inertial frame, the velocity vector does not reliably indicate the point of touchdown. It does, however, provide very precise rate information with respect to GS, with some small bias term. The typical habit for F-18 Hornet pilots is to place the Velocity Vector near the intersection of the decks (“crotch”) of the ship, and then gauge the GS trend. In doing this, the pilot is effectively leading the ship by placing the velocity vector at some point out in front of the wires where the ship and aircraft trajectories will intersect.
This initial placement ensures that the flightpath will very nearly hold the aircraft on GS. The precision of the FPA data also means that the effect of an input correction is immediately assessed in a variable that is very nearly GS rate (the state information necessary for the pilot to attain the elevated performance). As the aircraft approaches the in-close to at-the-ramp position, the velocity vector is allowed to drift aft to the point of touchdown. The fielding of HUD’s largely bears the responsibility for the improvement in boarding rate demonstrated by F-18 Hornets and F-14D model Tomcats over the aircraft that preceded them. One method to reduce pilot workload during the approach task is to improve pilot cueing. Because of the beneficial impact of HUD cueing on pilot workload during the approach task, it is recommended that HUD considerations be a primary consideration in designing for the approach task.
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LINEUP
Many of the historical carrier-based accidents are caused by lateral excursions from the landing area during some part of either the landing rollout or a bolter. Since the most common foul-line excursions result in Class 'B' or 'C' (i.e., no loss of crew or aircraft) damage, and lack the dramatic effect of a ramp strike, they do not receive the same attention. Moreover, if the aircraft lands within the wires (within the acceptable GS error band), a successful landing is fairly insensitive to errors in GS rate (sink rate). While the nominal sink rate of 14 fps is prescribed, aircraft loads are certified to sink rates in excess of 20 fps. With respect to lineup, it is not sufficient that an aircraft touchdown within a specified distance of the centerline; it is also vital that the aircraft touchdown with little lateral drift to keep the wingtips within the bounds of the foul line throughout the rollout. Carrier aviation has a lengthy history of aircraft touching down directly on centerline, but then impacting parked or taxiing aircraft with a wingtip during a rollout. For this reason, the backup LSO's principal responsibility is to monitor the lineup of each approaching aircraft. As mentioned previously, lineup control is significantly aggravated by the erosion of sensory information at night, requiring the pilot to devote more attention to lineup to the detriment of the control of the other aircraft states.
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Conclusion: The multiple constraints of CV landing are satisfied by the pilot's control of just three variables - GS, lineup, and AOA. Addition of error rate information improves closed-loop performance. The best closed-loop performance is achieved feeding back error rates rather than displacement errors themselves."
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This next lot of quotes from a recent LSO NATOPS MANUAL found online is perhaps again sometimes not relevant to the initial question but 'context' is required. I would encourage any interested to download these PDFs to see the text in context with many excellent illustrations (only some may be shown in this thread - if any). Enjoy.
NATOPS LANDING SIGNAL OFFICER MANUAL 17 June 2004
http://www.vaw120.navy.mil/NATOPS/UE_Instructions/LSO%20NATOPS.pdf (2Mb)
4.2.5 Stabilization Modes
The position of the SOT assemblies for any given ship’s pitch, roll and heave is calculated from a series of stabilization equations in the stabilization software. The result is a stabilized glideslope with respect to the horizon under moving deck conditions. The following modes of IFLOLS stabilization are employed.
4.2.5.1 Inertial Mode Of Stabilization
The Primary mode of operation for the IFLOLS. This Mode is line stabilization with additional correction for ship’s heave motion. It essentially stabilizes the glideslope regardless of carrier motion. The pilot must be on the centerline of the angle to see a properly stabilized display. During heavy sea states (5/6) in inertial mode, the hook to ramp clearance and touchdown point indicators will occasionally display a negative or aft touchdown point respectively.
The dynamic touchdown point varies more in inertial mode than it does in line mode. This is the sacrifice for a more stable light beam/glideslope for the pilots. A pilot on a perfect pass may hit any of the four wires, the ramp or bolter, depending on ramp motion and heave. At the moment of touchdown, the hook touchdown point will be displayed by the dynamic hook touchdown point indicator for a centered ball pass.
4.2.5.2 Line Stabilization
Used as a backup to inertial mode, this mode stabilizes the IFLOLS display for pitch and roll motions of the ship maintaining a predetermined line in space at the intersection of the IFLOLS light plane and the true vertical plane through the centerline of the angled deck (Figure 4-5). This provides a completely stabilized glideslope referenced to the carrier deck, (glideslope moves with deck heave motion) as long as the pilot is on centerline of angled deck.
Line mode is not stabilized for ship’s heave(vertical displacement). Pilot perceived ball movement is because of ship’s heave. Mode 1 should be flown using line stabilization mode, inertial is acceptable. IFLOLS Line mode should be used when aircraft are landing using ACLS Mode I. The aircraft chases the deck in Mode I approaches. For Mode I approaches IFLOLS Line mode provides a steadier ball to the pilot than inertial. With moderate and higher ship motion the pilot will still see some ball motion in the situation. Inertial mode should be used for ACLS Mode IA, II, III and all other approaches.
4.2.5.3 Stabilization Limits
Lens stabilization limits for the MK 13 MOD 0 are ±1.62 pitch, ±8.19 roll. It should be noted that in any discussion of deck motion and its associated effect on IFLOLS, rate of pitch is just as important as amount of pitch. A moderate amount of pitch, normally within the stabilization capability of the IFLOLS, can result in an unstabilized glideslope if the rate is rapid enough. The ballscrew assemblies simply cannot move to the required position quickly enough when the deck excursions are rapid.
4.2.6 Effects of Deck Motion
Using basic geometry, each 1-foot aircraft vertical deviation from optimum glideslope moves the hook touchdown point forward or aft in the landing area by the following distances:
Basic Glideslope Angle Distance in Feet
3 19.1
3.5 16.4
3.75 15.3
4 14.3
4.2.7 Effective Glideslope Due to Wind and Deck Motion
The glideslope angle, referred to as the Basic Angle (BA) aboard ship, is the fixed pitch angle around which the lens assembly stabilizes. A BA setting of 3.5 is most commonly used, with 4 used for higher wind-over-deck conditions (38+ knots) or on the small decks when Hook-to-Ramp (H/R) clearance is near the 10-foot minimum. In moderate wind-over-deck conditions (32 to 37 knots), a 3.75 BA may be desirable. In Figure 4-6, note that decreased closure rate of aircraft to ship caused by wind-over-deck reduces the actual glideslope flown (effective glideslope).
WIND OVER DECK (KNOTS) BASIC ANGLE (DEGREES) EFFECTIVE GLIDESLOPE*
35 4 3.2
30 3.5 2.8
*Based on a 130-knot approach speed
Aircraft landing stress limits are predicated on moderate deck conditions. Extreme deck motion may significantly increase these landing stresses; the ramp coming up at touchdown increases relative sink rate. Additionally, 1 of ramp down is the same as adding 1 to the glideslope as far as aircraft landing stresses are concerned. These deck motion factors are among the most critical to consider when landing aircraft on carriers.
During pitching deck conditions the aircraft hook may not engage the crossdeck pendant at the optimum angle. This may result in an apparent increase in the frequency of hook-skip bolters.
4.2.8 Roll Angle and Hook-to-Eye
IFLOLS Unit 1 has 12 light tables, one behind each lens (cell). These light tables are moved in unison to stabilize the source light plane for ship motion and to change the Basic Angle (BA) and set different aircraft Hook-to-Eye (H/E) values. To accomplish this the source light plane is rotated about two horizontal axes at right angles to each other, one axis called lens pitch and the second axis lens roll. While the IFLOLS Unit 1 does not have an actual pitch and roll axis, the source light plane rotates as if both axes were located within Unit 1. The lens pitch axis is perpendicular to the angle deck centerline and the lens roll axis is parallel to the angle deck centerline. The tilt in pitch, referred to as the basic angle, is seldom changed during a recovery. Typical basic angles are 3.5 or 4.0. See Figures 4-7 and 4-8.
Rolling (rotating) the source light plane, on the lens roll axis, causes the glideslope along the centerline of the landing area to be raised or lowered. This compensates for the various H/E distances to provide a constant hook path for all aircraft (Figure 4-9). H/E distance, which varies between aircraft types, is the vertical distance between the hook path and the pilot’s eye path relative to the carrier (see Figure 4-10). Aircraft Recovery Bulletin No. 62-12 provides H/E values for all aircraft and aircraft configurations. These H/E values, along with BA, desired hook touchdown point, and ship’s static pitch/roll miss trim, are used by IFLOLS to calculate and set the proper static lens roll angle. The static roll angle range of IFLOLS is approximately 8. Static roll changes do not account for stabilization of the source light plane for ships motion. A 0 roll angle is a source light plane that is level in roll. Increasing the roll angle raises the source light plane along the angle deck centerline. The roll angle is increased when changing from an aircraft with a small H/E to an aircraft with a larger H/E. Positive roll angles are roll angles that raise the source light plane above level over the angle deck centerline. For IFLOLS on 68 class carriers a H/E of approximately 16.5 feet with a 3.5 BA and 230 ft HTD results in a source light plane level in roll (zero roll angle). The static roll angles of current fleet aircraft (April 2007) vary approximately 1.5 except for the T-45 which has an approximate −3 roll angle.
For the CVN-76/77, 3 wires HTD 212 ft, the nominal roll angles are all approximately 0.75 more negative with respect to 4 wire 230 ft HTD ships. The CVN-78 will be approximately 1.5 more negative. The selected BA will not change when the lens roll angle is increased or decreased.
CAUTION
Because of roll angle pilots observing a center ball, but flying an extreme
off-center approach, may have hazardous hook to ramp clearance.
No roll angle or BA settings are used for MOVLAS as the LSO manually controls the ball to establish the proper glideslope. Most field optical landing systems change only basic angle (3.0 or 3.25); no roll angle adjustments are made, and each aircraft type will have a different touchdown point based on its H/E value.
All published lens settings are intended to provide optimum hook glidepath, with a hook touchdown point halfway between the number two and three crossdeck pendants (4 wire ships). Roll angle places the visual glideslope some distance above the hook glideslope that corresponds to each aircraft’s H/E distance. H/E (in feet) is determined for each aircraft while properly configured; flying on speed, optimum attitude, and with a centered ball. For many aircraft, a change in configuration will change H/E distance. H/E values for various configurations are specified in the Recovery Bulletins. If no preconfigured H/E pushbutton is available for the aircraft, IFLOLS has a Non-Standard H/E adjustment to provide the desired glidepath and hook touchdown point.
Failure to maintain optimum aircraft attitude to touchdown may result in engagement of other than the targeted wire even with the aircraft on the visual glideslope (i.e., pilot sees a centered ball) at touchdown. Additionally, pilots flying an optimum aircraft attitude and on a centered ball may also engage other than the targeted wire if there is appreciable ship motion.
Deck centerline camber (i.e., the centerline is higher than the deck edge) is for water drainage. On most decks it is approximately 4 inches. All lens settings in the Recovery Bulletins compensate for deck camber.
4.3 IFLOLS STABLIZATION INPUTS
IFLOLS receives ship’s pitch and roll information from either the ship’s gyros or SPN-46. IFLOLS receives ship’s heave information from either an IFLOLS generated ship’s heave signal or SPN-46. The IFLOLS signal is generated using the IFLOLS unit 5 accelerometer. The IFLOLS can use either ship’s pitch and roll gyro source with either heave source. When aircraft are landing using ACLS, any mode, IFLOLS should use the same stabilization inputs as SPN-46. Typically SPN-46, SPN-41, and IFLOLS will all use the SPN-46 gyro for pitch, roll, and heave information when aircraft are landing using ACLS.
7.3.7 Excessive Deck Motion
The decision to continue flight operations during periods of excessive deck motion must be made after considering many factors. These factors include but are not limited to the following: amount and rate of pitch, associated heave and roll, day or night, visibility and horizon, air wing and LSO proficiency, tanker and divert availability. Although there are no hard and fast numbers to define excessive motion, as a general rule, deck motion in excess of 20 feet of pitch in anything less than 5 seconds of periodicity should be viewed as an emergency situation. MOVLAS is the primary method of recovering aircraft during excessive deck motion, depending on other factors previously mentioned. LSO workload will be very high in these conditions. The LSO will most likely be required to make nearly continuous voice transmissions during pitching deck operations regardless of whether MOVLAS or IFLOLS is utilized. The LSO will most likely be required to utilize a steeper than normal glideslope as well as to ensure adequate hook-to-ramp clearance during extreme pitch cycles.
CHAPTER 8 Extreme Weather Condition Operations
8.1 DECK MOTION
The decision to conduct flight operations during periods of excessive deck motion must be made after considering many factors. These factors include, but are not limited to the following:
1. Operational necessity
2. Day or night
3. VMC or IMC
4. Amount and rate of pitch, roll, and/or heave
5. Visibility and horizon
6. Air Wing pilot and Staff LSO proficiency
7. Tanker and divert availability
Any number of these factors can combine to create a wide spectrum of operational risk. Measuring operational risk can be difficult, and there are no hard and fast numbers that define “excessive deck motion.”
The staff LSO, in conjunction with the Air Officer, shall inform the CV/N Commanding Officer when pitching deck limits are exceeded. The decision to continue flight operations will lie at the discretion of the Commanding Officer.
Flight operations with ramp movement exceeding 20 feet total is extremely hazardous. Flight operations in these conditions should be avoided.
Flight operations should not be conducted with deck movement in excess of 35 feet total due to zero hook to ramp clearance with the 4.0 degree glide slope.
Recovery of fixed wing aircraft with a pitching deck significantly increases the risk of hard landings, ramp strikes, off-center engagements and in-extremis low fuel states airborne due to the inherent decrease in overall boarding rate.
Note
The presence of dutch roll increases the risk associated with the recovery of fixed wing aircraft when compared to pure pitch, and should be taken into careful consideration prior to conducting flight operations.
8.1.1 Flight Operations in Pitching Deck
When deck motion exceeds the stabilization capabilities of the IFLOLS as determined by the Staff LSO (approximately 8 feet of total deck movement in less that 4 seconds), utilization of MOVLAS should be considered for fixed wing aircraft recovery. If the deck is steady for extended periods between deck swings consideration should be given to leaving the IFLOLS rigged and utilize LSO talk-downs during deck swings. This will maximize boarding rates.
Note
IFLOLS Stabilization capabilities are approximate and may vary depending on CV/N.
8.4 EXCESSIVE DECK MOTION
Recovery operations under conditions of excessive deck motion are discussed in Chapter 7 of this manual.
8.5 EXCESSIVE WIND-OVER-DECK OPERATIONS
Turbulence and ramp burble increase significantly with RHW values in excess of optimum, resulting in an increased frequency of high landing gear loading.
Excessive crosswinds adversely affect recovery operations. If the recovery crosswinds exceed 7 knots, rates of descent 3 to 6 feet per second in excess of those experienced during normal operations can be expected, even with corrective pilot technique.
Shipboard aircraft recovery operations with recovery crosswinds in excess of 7 knots require the approval of the CV/N commanding officer.
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This highly detailed LSO Reference is no longer where it was found online:
LANDING SIGNAL OFFICER REFERENCE MANUAL (REV. B) 1999
CHAPTER 17 ENVIRONMENTAL FACTORS
17.1 GENERAL
An analysis of past carrier landing mishaps has shown that over 25% of causal factors were environmental in nature. Pitching deck was the single most influential factor, involving 15% of all mishaps.
17.2.8 Pitching Deck. Deck pitch due to sea state is difficult to predict and causes numerous safety concerns for the LSO and pilot. Care must be taken to ensure that aircraft are waved off in a timely fashion if out of phase with the deck approaching the waveoff window. As the deck pitches, it dwells longest at its maximum up/down excursions. Deck pitch normally has a characteristic ten second cycle, however, occasional hesitation or random periods of steady deck may occur.
17.2.9 Heave. Natural heave occurs as result of variation in the force of buoyancy from greater to less than that of gravity; the ship bobs up and down. Heave is less predictable than pitch but rarely exceeds 5.5 feet.
&
Improved Fresnel Lens Optical Landing Aid System (Mk 13 MOD 0 IFLOLS)
2.1 GENERAL
IFLOLS will replace FLOLS on all Navy carriers and selected field carrier landing practice (FCLP) sites by the year 2002. It is a derivative of the Vertical/Short Take Off Landing (VSTOL) Optical Landing System (OLS) used aboard LHA and LHD class ships....
2.2 ADVANTAGES
The main advantage of IFLOLS over FLOLS is that it allows the pilot to receive more accurate glide slope information from one mile out to touchdown. This is done by increasing the height of the lens from 50 inches to 72 inches, while making the same range of glideslope information as the "old' Mk-8 FLOLS thus increasing sensitivity, making the lens twelve vertical light cells tall rather than five. This gives the pilot a more accurate and earlier visual cue of ball movement, allowing him to correct quicker since the ball movement is more pronounced than in the present system.
Other improvements that enhance IFLOLS capabilities are internal stabilization so that only the lens moves as it compensates for ship's movement rather than the entire platform, it uses fiber optics, is less sensitive to temperature, has printed circuit boards, and increases visual range due to improve optics. (Useable 1 1/4 - 1 1/2 miles out at night.) IFLOLS stabilization algorithms are digitized form of FLOLS algorithms with approximations replaced by "look-up" tables and known data points.
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Thank you spaz, that is very informative reading for me. Thank you for posting and I've copied for notes to re-read.
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Going back in the thread just a little,
@Microbrewst
Just wanted to say, great movie microbrewst! Hope you do some more of this!
I'm trying to discover how to make the carrier pitch and roll the way it is on your vid. I have to say I've got nowhere trying to figure out how to do it.
That's Javier's carrier, am I right? But have you got it running in a package like "Carrier Ops" or Abacus "Flight Deck" or something, or is this an FSX tweak that you know of? Any clues as to how this is being done, Micro'.
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Sorry for not responding fellas. I'm out of town right now. When I get back home I'll try to give a good write up of what I'm working on. I say "working on" because I haven't gotten everything to work yet. Will report back in a few days.
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Spaz
I think thats the longest answer to a question posed in a flighsim forum in the history of forums.. ;D
Very interesting reading, amazing what technology has produced. My question was directed at FSX as I realise IRL.there is no way in heavy seas that the
meatball is going to bob neatly at the same height as all hell breaks loose around it there are far too many forces at work ie heave, swell, roll, pitch etc...
Are there any known procedures , tips tricks etc... to landing on a pitching deck that you know of ? would make some interesting reading ...I really hope
That Microbrewst manages to get this working , with all the realistic improvements to this sim in the area of carrier ops for us naval enthusiasts christmas really has come early this year.
Now all I need is Varmints FSX VRS Superhornet and I can die a happy man!! thanks to everyone that has contributed to the upgrade of this sim.
SonofaBeech out
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sonofabeech, the long answer was necessary because really there was no short answer unless I knew that you knew that I knew that you knew... oh forget it. ;D My research/answers are also helpful to me (making the 4.4GB PDF available online that is regularly updated). By answering questions often that answer goes into the PDF. Anyway I find it interesting to get to know what carrier ops are like today with the Hornet / Goshawk.
It is not clear (to me) from your question above whether you would like an answer specific to FSX or a real world answer OR both. ;) I always claim that they are one and the same if one is using FSX; and after all that is what we are doing. UNLESS there is something specific in FSX that needs to be addressed. In any event I cannot know what you are doing in FSX unless you are very specific about conditions etc. All I can do is give a general answer that most likely applies to both - BWDIK (But What Do I Know?). ::)
Whatever the carrier is doing becomes irrelevant if you are using 'meatball, lineup and airspeed'. Nothing else matters. However in the real world apparently - if conditions are really bad - the LSO can use the MOVLAS (manual mirror) to guide the pilot. The LSO actually moves the meatball, often leading where the aircraft is going, to get a better response from the pilot. Also the LSO will talk more to help the pilot (usually he says nothing). Another solution is: 'don't fly' or 'bingo to the BEECH'! Runways don't move. ::)
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Thanks SpazSinbad
As always your answers make really interesting reading.
Thank goodness FSX and IRL are not exactly the same thing otherwise instead of 600 ft a.s.l with a cold beer at my right hand calmly guiding the hornet towards the carrier i would be sweating in terror crapping myself over my impending death :o
Now I know that you knew that I know that you knew that i kn.......
AAANyway it seems the gap between real life and the sim seems to be getting smaller as each day
passes..... what on earth will the sim be like two years from now :o
SonofaBeech out