OutOnTheOP

So I'm still a bit confused... if you slave SPI to a moving target, will CCRP attempt to "lead" the target? For CBU103/105? What about CBU87/97? I always assumed they didn't, so I my technique was: 1) lock moving target in TGP. Make SPI 2) set CCRP. Note time-of-bomb-fall in left side of hud. 3) Divide time in time-of bomb-hall in half. Estimate an intercept point that many seconds ahead of moving target (this point will need to be updated through the attack to ensure it remains the correct lead distance ahead). Shift the SPI onto that lead point. For CBU97, add 5-10 seconds of lead to account for time under parachute. 4) Set shallow dive; aim to release bomb at half the altitude you started at (IE, spot target and begin attack at 10K AGL and 40 seconds time-of-bomb-fall; release in a dive at 5K AGL, which means leading the target by 20 seconds). The dive is (in my eyes) somewhat important, as it reduces the time-of-fall, thereby reducing the distance the target moves while you're in a dive. 5) Profit! I've gotten reasonably good results with this technique; it's a little harder with CBU97/105 than with CBU87/103, due to the extra (and somewhat unpredictable) delay imparted by the parachute deployment on the 97/105. I really should do some testing by dropping CBU97/105 with different Height Of Function settings and time exactly how long it take the parachutes to descend. I'll get to it eventually.

1) the JTAC will direct you to targets using a 9-line request. The 15/30/45/60 is so you can tell him how long you will be available to help him. 2) Again, set by DSMS. I usually do not pre-set my profiles, because it doesn't take me that long to set them up, and I like to vary my delivery mode and settings as suited to the situation. 3) like #2, set in DSMS. If you're losing your settings, it's probably because you are selecting your weapons by using the DSMS page to select hardpoints. Instead, select with the DMS switch on the HUD (I think... again, I generally don't select that way; I prefer to set up my settings on a by-attack basis) 4) This is because you are using CBU97; the "defying gravity" bit is due to a rocket motor. This is correct behavior.... except the part where it's only destroying one target. It should independently target multiple vehicles. However, if you drop the CBU97 centered on ONE tank, it will often shoot most of the submunitions into that one tank. It's usually more effective to aim the bomb BETWEEN tanks. See for a demonstration of CBU97. 5) SEAD is put in by triggers in the mission editor, so if the mission maker forgot to put in a radio call, there just won't be one. Sorry. My experience has been that in most of the campaign missions, SEAD won't check in on station initially, but they will make all their "engaging target" calls, and they'll call when they RTB, as well as when they're BACK on station after RTB. 6) As mentioned earlier, you have to be on the right frequency. Also, you have to be close enough to the "holding area" ATC directs you to; this is where the tower AI considers you in position for landing. It's usually about 15-20 miles away from the runway, on line with the runway. I'll admit, ATC is a bit wierd for me too. 6)

Aww, sniped! I was going to point out the radome was (edit: RF-transparent) transparent. However, it is ALSO worth considering that if you have two AMRAAMs heading toward each other, in the same piece of airspace, transmitting energy on the SAME FREQUENCY, the missile might "think" the emissions from the other AMRAAM is jamming, switch to Home On Jam mode, and home in on the radiating emitter that is "jamming" them. ...but as has been said before, how a real AMRAAM would behave in this situation has nothing to do with the observed results in this case; if the programmers programmed the simulated AMRAAM to be able to see and home on other missiles, that's what they'll do.

I like the higher-threat missions because they're fun, and I like having some medium-high range threats (either air or SAM) because it forces the player to change his tactics. In missions where there's just SA-9, MANPADS, and AAA, the sortie inevitably turns into a bomb-truck milk run; straight in at 30K AGL, drop guided bombs from straight and level, turn around and go home. Snooooooore. However, it's unrealistic to make destruction of the SAM threats a success criteria, and there's certainly such thing as too many SAMs. Personally, I see 1 SA-9/13/8/15/2S6 per tank or IFV company as a reasonable ratio. 10 tanks/IFVs per mobile SAM platform. one SA-6/11 mobile medium-range battery (no more than 4 launchers) per tank/IFV battalion is about right. (and these should be farther back, nearer where the artillery positions are than the leading armor!) Missions with a dozen medium-range or long-range SAMs covering a platoon or two of armor is silly. I'm not a big fan of having fixed or semifixed sites (including SA-10) around, because they'd have been dealt with long before the A-10s were fragged to the area. *edit* I totally agree that the response time for some of the SAMs is totally ridiculous. They seem to never have any ambiguity over whether you're a valid track, whether you're hostile, or whether you're worth engaging. On the flip side, they're also pretty stupid about consistently engaging at maximum range. Older systems setting up from the march, and MANPADS are particularly bad about their too-quick responses. When I pop up over a ridgeline, it's just not realistic for an SA-18 team to spot, identify, track, and engage me in two seconds.

Fixed. :D

You mean... there's other ways to fight software piracy than shutting down the internet?!?!? .... (totally tongue-in-cheek, by the by. I have SB Pro, so I'm familiar with the dongle. And last I checked, SB isn't a heavily pirated game, despite the $150+ price tag. So it must be working for them)

Sounds about right. I reiterate; why would anyone make an interceptor primarily armed with rear-aspect missiles, then fail to make it agile enough to ever acheive a rear aspect shot? :noexpression: And I still say F8 Crusader. Classic gunfighter- now with with AIM-9 for extra fun!

As a side question, does anyone know if the new GBU-54 LJDAMs can have their laser code programmed in flight? I mean... given that they're JDAM munitions, they MUST have a data cable connection to the host aircraft....

so the verdict appears to be "possible, but shouldn't be part of the attack plan". About what I figured; it would just be SO much easier if the DSMS would allow you to actually set up ripple release options for LGBs. Estimate ground distance between targets, set ripple spacing, hit the pickle once, and then shift the TGP after the first impact.... would be SO much easier... Come to think of it, the videos I have MAY have in fact been conducted by 2-3 aircraft, with the two subsequent impacts released by seperate aircraft, guided by one of the two or a third, spotter aircraft. That would certainly allow more flexibility in the timing between impacts...

I know I've seen it done before: two LGBs are dropped, several seconds apart, with a first, nearer target lased until impact of the first weapon, then a quick shift of the TGP lazing until impact of the second. I am aware the videos I have seen are almost certainly from F-15E or other multiseat aircraft (*edit* likely F-111 as well), where the WSO can concentrate all his effort on this task. My question: is such a 2-LGB pass even possible in the A-10? For kicks and giggles I gave it a try on the "weapons training" mission, dropping (well, attempting to) on the near and far end of the two tank columns at the "Tanks" waypoint. I used markpoints as per multiple JDAM deliveries. From 20K AGL, even with such significant lateral seperation (it's got to be at least a good quarter mile between the far ends of the two columns) I found it virtually impossible to drop the first weapon, shift my SOI to the second markpoint, and line up fast enough to get the second weapon away. Usually by the time I had called up the second markpoint, the CCRP was already at -3 to -5; I was behind the release timer by quite a bit. Has anyone been able to accomplish this feat? How?

yeah, F-104 would be by FAR my last choice from that list; it has the handling characteristics of a neurotic ballistic missile, and a nasty tendency for departing controlled flight. And who the %$(@ came up with the idea of making a non-maneuverable high-speed interceptor armed with WVR rear-aspect-only weapons? I mean.... if it can't turn, how's it ever supposed to employ them? At least F-102/ F-106 was a BVR platform.... *edit* Hm, I stand corrected. I thought the AIM-4/ AIM-26 had a considerably longer range... especially considering the latter was nuclear-tipped. I know *I* certainly wouldn't want to be firing nuclear missiles with a maximum range of a mere 6 miles >.<

I like this idea. Arma 2 did something similar, with an option for faint glowing "halo" around units that directed attention to them; it fades as you get closer. In Arma 2 it was desperately needed, as the enemy had a tendency to spot you at distances reflecting "real life" (200-300 meters in the open), while the limitations of the computer screen meant you generally couldn't see them until 100-150 meters. It's something of an equalizer. Falcon 4.0 had another interesting workaround with the scaling sliders; it essentially made units larger the farther away you were, so their apparent size was still enough to spot them (IE, not a single pixel). Another way might be to include a subroutine that increases the contrast of the enemy unit the farther away you are: IE, if it is a dark green tank on a dark green field, from 5 km away it currently appears as a dark green pixel on a dark green field: instead, it could be made to appear as a LIGHT green pixel on a dark green field. I really like the sunlight glints as well. Ideally these would be calculated from the actual raycasts from sun location, but simplification would be fine.

You know what I'd like to see even more that isn't on the list? F-8 Crusader. Or MiG-21. Which would be fantastic because it's a classic... and still in use by many nations. Better yet, a paired release: F-8 versus MiG-21

Good point on runway visibility. As to masking the airbrakes, I dunno... if you're masking the airflow to the upper half of the airbrakes, you're doing so by masking it with... an even larger aerodynamic surface. And presenting a larger surface area/ flatter angle to the flap surfaces. I'm not sure I've noticed much difference in deceleration in DCS between airbrakes versus airbrakes+nose-high. I know in Falcon 4, nose high beats airbrakes every day. Can't speak for the real aircraft one way or another.

airbrakes + nose-high attitude !> airbrakes ? it's not like the F-15 has no ginormous airbrake....

Ok, so a lot of people are arguing over a question that wasn't posed. The question was "would YOU pay $500 for a flight sim?", not "would a $500 flight sim be a viable business model?" Are there people who WOULD pay $500 for the right software? Yes. I have dumped easily $350 into software, additional licenses, and updates for Steel Beasts. I have dumped a couple thousand into DCS A-10 (though this was in the form of a TMWH, touchscreen monitors, extra graphics cards et al rather than the software itself). I plan to drop a few thousand more on building a simpit. But then I also spend easily $800 a month at the rifle range on ammunition. So it would be silly for me to not be willing to spend half that on software that I can use month after month. However, if you want to argue over whether a $500 sim would be successful... well, I don't know. On the one hand, you lose a lot of "casual gamer" purchases. I would contend that you're probably not getting that many of those right now anyhow. Even with the "casual" mode in DCS, the "casual gamers" are going to go elsewhere for their purchases. They're much more likely to buy Ace Combat or Jane's Advanced Strike Fighter or similar, because those games offer multiple "cool" airplanes to "fly", a cinematic experience, and other gimmicks that attract the casual gamer. There IS a market for an expensive simulator. eSim is already exploiting that market with Steel Beasts Pro PE. Yes, it's primary market is the military sector. Funny, seems to me that's DCS's primary market as well; both DCS:BS and DCS:WH were initially developed as government purchases. Where does the price point for a successful commercial simulator end? I would say around the $150-200 price point. At $150-$190, a purchaser is likely to think along the lines of "oh, that's the cost of just two normal games". At $500, they're more likely to think "that's half a thousand dollars!" The MOST successful method, I think, would be essentially what ED is already doing (which is essentially what Rise of Flight does as well): release MODULES of individual pieces of equipment which all interoperate in a common game engine. Unfortunately, DCS has been doing so way too slowly. While ROF has been releasing modules at a pretty rapid rate, allowing them all to function together as one large game, the DCS releases are so slow in coming that there have been major changes in the game engine (or in underlying computer technology) between them, forcing major changes in the older module(s) between releases to ensure compatibility. At the rate modules are coming out, by the time we see a full virtual battlefield, DCS:BS will be so old it will be like trying to play a co-op game with one player on a supercomputer and the other on an Atari 2600. And yes, I am aware that WWI aircraft require much less programming and development than modern aircraft and equipment. The point is, if they ever want to realize the "virtual battlefield", they need to start pumping out product faster. They need to realize that then they would see a synergetic affect; people would buy modules based not only on the quality of the module they're buying, but because people WANT TO FIGHT AGAINST HUMAN OPPONENTS. Maybe ED should consider providing SDKs to select companies to start developing different "lines" of modules; like having the eSim guys develop a line of tank modules and have Sonanalyst make naval modules. (yes, I know, the game engine differences means that the eSim guys can't just directly port their already-developed software directly into DCS. My point is, get more folks aboard). Even if by doing so ED loses the opportunity to make their OWN tank/ ship modules, a 5% royalty on someone else's module is still better than 100% ownership of a product they never get around to producing.

Oh, stop already. The question he's asking is which one you want, not which one you think is next. As for me, A-4. Barely more technologically advanced than the MiG15/F-86, small, light, maneuverable, and reputedly pleasant handling characteristics, and a surprisingly large payload for it's size. Used by many, MANY countries. Multi-role (for it's time, when BVR was very hit-or-miss). F-4 is neat, but it's two-seat, which does add some issues with the simulation (particularly since unlike the F-15E, the F-4's controls are not replicated in both seats). Besides, the F-4's handling characteristics were kinda crap, it wasn't very agile, and early marks had no internal cannon. I'd love the F-111, but it's too new for me to consider it a "legend"; it was just barely entering service at the end of the Vietnam war.

I noticed that while aero braking was mentioned a couple times in this post, no one seems to have explicitly explained what it is. I may be wrong in my assumption, but I assume what you're referring to is holding a nose-high attitude with the nosewheel off the ground after touchdown for as long as possible; it turns the entire wing and stabilizer surface into a giant airbrake.

Looks like Cali's thinking along the same lines I am- I would most certainly pay $500 for the "perfect sim", but this sim would be a full virtual battlefield. Like Arma, but at a DCS level of fidelity, and a continent-sized play field. Take the Arma infantry interface, Steel Beasts Pro PE tank interface, 688i Hunter-Killer/ Dangerous Waters naval interface, DCS-level aircraft interface, a SAM operator simulation, FOPCSIM artillery/ FO interface, and put them all together into a single piece of software (or as modules to a common engine) with an enduring dynamic campaign. I would EASILY pay $500 for that. And still feel like I'd gotten a steal.

I seem to recall the old EF2000 game incorporated exactly that in the air-to-air gun mode; you locked a target, held the gun trigger depressed as a "consent", much like CCRP mode, and when the target passed the reticle, the computer automatically fired the gun. http://typhoon.starstreak.net/Eurofighter/weapons.html seems to corroborate this is also true in the real Eurofighter

well said, Brum!

Unfortunately I left most of my books stateside; I'm currently in Korea. The War Without Mercy book is much more... scholarly, in the way it reads, but has many good examples of the period propaganda and vignettes of incidents from both sides of the conflict. Going from memory, I doubt I could do either justice. I do recall the German policemen (actually, I think they were locally raised from Polish population; it's been a while since I read it) being really disturbed when they received their first order to conduct a mass execution... the officer offered to let any who wanted out leave, and the general opinion was "we don't want to do this, but orders are orders". What was striking was that they went through all the effort to plan how to make it "humane". I recall mention of things like consulting with a doctor for the quickest way, using a bayonet placed at the back of the neck as an "aiming guide" to ensure a hit resulting in instant death, and some manner of organization of the order in which family members were killed and keeping the waiting folks out of hearing range to make it less "emotionally stressfull" on the people being executed. The mere fact that they could calmly plan those kind of details in that situation is, well, really disturbing. Even worse was the description of how, after going through this routine a few times, the executions no longer horrified the policemen, and they saw the whole ordeal as a NUISANCE. By that point, the people they were executing were just things to them, and any pretense of being humane was gone- the victims were simply marched to the woods, made to dig their own graves, and then haphazardly machinegunned. There were a number of descriptions how the executors didn't bother to aim anymore, and many of the victims were only wounded by the initial shots, to be perhaps finished off with a burst from an SMG sprayed around the mass grave- or even simply buried alive. But I really can't do the book justice; you'd have to just read it... the description of the whole process transforming people from run of the mill workers into dispassionate killers is really powerful and a good cautionary tale. I think it's important to understand that evil men aren't just born evil (well, not all of them... granted, there are some that are simply psychologically damaged), they are conditioned to be evil. Germans aren't genetically predisposed to hate Jews, or to be evil, they were conditioned to. Basically, in the right (well, more like wrong) situation, ANY group of people could be made to behave as the nazis. That's a scary thought. And as far as racism goes, I wouldn't be so presumptious as to say I have none, but I generally like to consider myself fairly evenhanded as such things go; there's really no ethnic group I hate per se. I just hate the notion that there is "good" and "bad" racism; that "pro" racial statements about minority races are somehow good, while "anti" statements about minorities (or, by extension, "pro" statements about majority races) are bad. As far as I'm concerned, there's only one kind of racism, and it's all bad. ANY attempt to state that races are qualitatively different (beyond some truly minute and fairly physiologically insignificant cosmetic differences) is kind of silly. I *do* dislike the "thug culture" often associated with the young US black community, but let's be honest here: the culture, and the problems that stem from it, are the result of the socio-economic situation disadvantaged inner city black youth find themselves in. Were any other ethnic or racial group put in the same situation, I would expect a very similar outcome. And in all fairness, I hate the (at least where I'm from) predominately white raver culture just as much, and for fairly similar reasons (IE, the culture promotes illegal activity by claiming it as "cool"). I'm an equal opportunity hater? I should clarify: I don't really give a whit about the MUSIC, some of it is even pretty catchy- no, I'm talking about the subculture. I dislike any subculture that promotes outright criminal activity (particularly for personal gain!), don't care if it's the current "rap culture", white supremacists, quasireligious cults, conspiracy theorists, or soccer hooligans. I don't hate Arabs, I hate terrorists. Some terrorists are Arabs. Some Arabs are terrorists. Most Arabs are not terrorists. ... I feel like this is an inadequate explanation of my feelings on the differentiation between race and culture/ ideology... but I hope you understand what I mean. That said, some of my best NCOs have been black sergeants (including my current one, who's a great guy, and who- perhaps ironically- enjoys engaging in exactly this manner of political/ academic discourse just as much as I. I've had a similar discussion as this with him before, as it happens). I've only ever put two soldiers up for bronze stars (both for the same action); one was a meek, lanky white kid from the midwest, the other a rather outspoken inner-city new york black man (kid doesn't seem appropriate; he was about my age; joined late). Incidentally, the two were damn near inseperable, which was always hilarious since they were such diametric opposites. Still wish I had the both of them in my current unit; they were both excellent soldiers (and I hope they stayed in; the black fellow in particular was a natural leader. Would make a good platoon sergeant someday). I've also had some excellent soldiers who would probably be described by most Americans as "total hillbillies"; about as stereotypical white southerner as you get; but still wonderful guys. And if by any chance Treece is reading this; dude, you need to get back in college; you're way too smart to not have a degree! So, as you can perhaps tell, I have very strong feelings about the notion of differentiating people by race, good or bad. There's just so much better things on which to base your opinion of someone! ...but I still hate the rap and/or "thug life" culture. And that's a totally different story from hating blacks. There's plenty of white kids that buy into that culture, and I think they're idiots too. And I have TOTALLY highjacked this thread, so I'm gonna shut my gob now.

Oh! Since I posted my thoughts here full in the expectation that I will get blasted with accusations of racism, I feel I should "redeem myself" with a couple offerings of what I thought were truly GOOD works covering the subject of war and racism. So, on the subject of war and racism... if you want some REALLY insightful reading (and some truly frightful insight to the horrors humans are capable of when they allow themselves to differentiate races), I humbly suggest you check out the following books: War Without Mercy: Race and Power in the Pacific War (accounts the rampant racism on part of both the US and Japan) Ordinary Men: Reserve Police Battalion 101 and the Final Solution in Poland (this one frankly horrified me; it outlined the progression of a group of middle-aged Germans from ordinary farmers and craftsmen to the executors of the Holocaust in such a believable way that really puts in perspective how an otherwise normal person can be manipulated into a mass murderer. Truly chilling stuff; the descriptions of the first few executions in particular: the policemen tried to justify themselves/ make the murder more palatable by trying to be 'humane' by consulting a doctor to determine where to shoot so as to result in the swiftest, most painless death- as though that lessened the crime? ) Anyhow, I think these two are of value for their insight into HOW and WHY people end up committing these crimes. Be warned, though: they are thoroughly uncomfortable reads, and you'll probably totally lose hope in the inherently good nature of humanity for weeks after.

Nah, I also didn't laugh out loud. Though I did find their commentary at times hilarious, even if the button-fumbling made me cringe at times. I was there once, too.... I think they did the software justice, though. They didn't try to candy-coat how hard it can be, they commented on the feeling of accomplishment one can get from succeeding in even simple tasks in the software, and they did a decent job of showing the depth of the simulation. All in all, it was put forth in a way that will attract those who are naturally inclined to be interested in this type of software, and which won't leave the more casual gamer feeling gypped from getting conned into buying it as a result of false promises. And it was funny. Let's not forget that! (for that matter, they actually made a pretty decent showing for themselves once they got airborne! I have to say, I didn't really expect them to hit anything!)

Yeah, I just figure... it wasn't all THAT long ago since the last Tuskeegee Airmen movie came out, and it's not like the movie was bad and needed rehashing, I think. It would just be nice to see something NEW, a story we're not all already familiar with. But then, that doesn't seem to be the way Hollywood does things these days; seems like everything is a retelling of some older movie, '80s cartoon, or comic book. Very little original coming out lately. Oh.... Wind Talkers. Ugh. I guess I'll have to admit some hypocrisy; I dislike that one simply because it focused too LITTLE on the actual Windtalkers. I had the same issue with it that I did with Last Samurai: it ostensibly told the story of a group of people, but for some reason had to do so through a proxy (Nicholas Cage and Tom Cruise, respectively). If you want to tell the story of a group's contributions, tell THE STORY, don't throw in some token character just to identify with the audience. Like I said, perhaps hypocritical to my previous posts, but I saw some distinct differences in the way Wind Talkers was presented... and more than anything, Wind Talkers was something new, that most people hadn't heard about. I guess the difference is I didn't see as much of the "us versus them" subplot in Wind Talkers... I just wish it'd stayed closer to the subject matter. I don't think I'd be nearly so incensed about Redtails, if it weren't for the fact that basically the last major WW2 fighter pilot movie (well, US, anyway) was ALREADY about the Tuskeegee Airmen. I just wish Hollywood would share the love with some of the other groups out there. I mean, since the 1980s, you have Memphis Belle in 1990, Tuskeegee Airmen in 1995, Pearl Harbor in 2001 (though that one was so atrocious I don't know it should count!) and... Red Tails. That's it. Half of the WW2 aviation films made in the US since 1980 are about the Tuskeegee Airmen. Half! *edit* while looking at the list of WW2 movies on Wikipedia, it struck me that it's not just the aviation movies where one sees this! Look at US movies about WW2 ground forces since 1980: Big Red 1, 1980. Sahara, 1995. Saving Private Ryan, 1998. Thin Red Line, also 1998. When Trumpets Fade, ALSO 1998 (apparently this was the year of US WW2 infantry movies?). Band of Brothers, 2001 (miniseries, not movie, but still counts). Windtalkers, 2001. Only the Brave, 2005. The Great Raid, 2005. Flags of Our Fathers, 2006. Miracle at St Anna, 2008. Everyman's War, 2009. The Pacific, 2010. Little Iron Men, 2011. So, since 1980; 14 US-made films about ground combat in WW2. Of these, Windtalkers is about Navajo code talkers, both Only the Brave and Little Iron Men are about the Japanese-American 442d RCT, and Miracle at St Anna is a wholly fictional account, where 3 black soldiers and 1 Puerto Rican bravely stand up against a nazi atrocity- it even has the prerequisite evil racist white officer abandoning them to die. So, 4 of 14 US made films about WW2 ground combat are... about the small proportion of combat units composed of ethnic or racial minorities. Perhaps more representative than the films about WW2 aviation, but still hardly representative, and seem to me a symptom of the political correctness so rampant in the US today. (a caveat: I may have missed films; this was not out of an attempt to manipulate statistics, but simply because I just pulled the wikipedia 'list of WW2 films' instead of spending the time on in-depth study) I will never understand this fixation. Bad things happened in the past. It is important not to repeat these bad things. It's probably not neccesary (and is honestly a little contrite) for a generation that wasn't even alive at the time the offenses were committed to attempt to repent for actions by their forefathers by making film after film about the matter. I think the brilliant pre-battle speech in Kingdom of Heaven about sums it up: "None of us took this city from Muslims. No Muslim of the great army now coming against us was born when this city was lost. We fight over an offence we did not give, against those who were not alive to be offended." Much the same; the current generation is struggling to come to terms with offenses they did not commit (well, ok, there's still been racist offenses in the current generation, but I'm referring to the institutionalized racism prior to the 1960s), and the brand of "equality" driven into their head in school leads to a society-wide feeling of a crushing need for atonement; ironically, that has kept the race issue alive by continually emphasizing our differences. I guess it's not good enough to just admit we're all human? Totally aside from aviation, I really wish they'd do a film on the US pacific submarine fleet in WW2; those guys were REALLY unsung heros. All The mortality rate was unbelievable- and yet all the sailors volunteers. Makes one wonder if they realized when they signed up, just how dangerous it was. Just watched a documentary on the USS Lagarto, and it made me realize I'd really never really seen any (theatrical) films on the subject.