Seafire Vs SpitV (2011)

[Urchin]

The charts would seem to be misleading to me if they don't represent the same configration for every plane across the board. If a given weight for the chart doesn't match a 'stock' configuration for a plane I would call that chart misleading, even if it is accurate for the given weight.

[dtango]

The charts would seem to be misleading to me if they don't represent the same configration for every plane across the board. If a given weight for the chart doesn't match a 'stock' configuration for a plane I would call that chart misleading, even if it is accurate for the given weight.

So are real life climb rate and speed charts misleading since they don’t represent the same configuration for every plane?

[Krusty]

If Republic had promoted the P-47N as having a climb rate of 6000 fpm because they tested it with only 5 minutes of gas onboard and no ammo, they would have been sued, fined, and lost a lot of business. You'll find most official WW2 test charts were some standardized loadout, mostly full fuel (except where expressly noted in clear text because it was rare not to) and these could be compared to each other.

A baseline is that, something you can compare. If you have to start discussing debating "But what if he had an uplift in that climb test? What if there was a headwind slowing him down 25 mph?" the chart is frakking useless. Same goes for weights. The charts are useless without some standardization of weights, or at least choosing a real possible weight from the hangar loadout screen (rather than some fictional weight part way between 75% gas load and 100% gas load, as on the Fw190F8).

Once you HAVE that baseline, you can compare and consider "What if I flew it lighter" and so forth, but you need the common ground to begin with IMO. What good is a photo finish showing identical winners without the fact that one of them started the race 5 minutes late? (hypothetical, related to the Fw190f8 identical charts though)

[Urchin]

Krusty answered it before I could, Dtango.

But I believe that most charts reflecting performance ARE standardized - for the reasons that Krusty outlined.

[Guppy35]

That's what I remember hearing from the spitdweebs back when the V and the Seafire were still running high boost.  That otherwise they were as good as identical in all respects.

What folks never seem to get about the old LFVc we had, was that it's performance was that good at the alts folks were flying it at.  The Spit FIX we have was geared for better performance at higher altitudes, so the LFVc actually had better performance up until about 12K feet over the IX.  Figure it's lighter too, and it was going to be a beast in the AH low alt air combat where folks like Lev and others did their best work.

[moot]

Yep.  Found out the hard way dragging a Spit IX all the way to 35 kft in a 152 back when it'd just come out.  Stayed 3.5 out the whole time.

[BaldEagl]

The charts would seem to be misleading to me if they don't represent the same configration for every plane across the board. If a given weight for the chart doesn't match a 'stock' configuration for a plane I would call that chart misleading, even if it is accurate for the given weight.

Agreed.  I find it hard to believe that most players playing the game even know what a specific aircraft's weight is.  I always thought the charts were based on some standard configuration.  As it is I'd say they are pretty much useless.

[dtango]

Seriously guys, to suggest real life WW2 flight tests followed some weight configuration "standard" so that you could easily pick up any flight test data and compare airplanes is revisionist history at it's finest.  But I acknowledge this isn't your main argument on the concept which does have strength.

Your main argument is about how to have fair comparisons.  I'm in absolute-heart-&-soul-city-of-brotherly-love-math-geek agreement with you when comparing things the only way to truly compare is to normalize all the variables.  When you compare apples & oranges this can prove challenging.  So I see the validity of finding common denominators for comparisons among very unlike things.  I accept having AH charts based on a common fuel load %'s in AH is one way of doing this.  This is because we can't truly normalize to the degree we would like.  

But in our specific case of SpitV/SeafireII or 190A-8/F-8 we're not talking about apples & oranges, it's more like an apples to apples Red Delicious to Honey Crisp comparison.  You don't have to find common denominators among the uncommon to compare.  You can truly normalize the variables like, *gasp*, comparing them by the same weight.  

It might be from a pilots perspective you're not thinking about plane to plane comparisons via a specific weight like this.  However when you enter the realm of evaluating flight models you're in the world of aerodynamicists involving many more maths and many more realities to account for.  So if someone's going to bring a claim that the flight model is wrong they better have accounted for the myriad of realities before they say something is wrong.  And when they haven't done so proving their FM injustice to be mythology to say that the chart "made me do it" is just silly to me.

Peace out 

[Urchin]

I'm not saying you are wrong when you say the two planes will have the same performance at the same weight. You either seem to think that will be a common occurance or (which I think is more likely) you are tweaking Krusty for the simple sake of tweaking him.

I know if someone comes up to me and says "Hey, I'd like to test this bullet to make sure it is ballistically matched with this other bullet" one of the first things I am going to check is the weight of the bullet. I don't give two craps if the two bullets are ballistically matched when bullet A is 4 squares if the standard weight for bullet A is 2 squares. Sure, if both bullets weighed 2 squares you wouldn't have to adjust your aim point, but the simple fact of the matter is they aren't going to be 2 squares.

Granted, that is ballistics and not fancy pants aerodynamics... but I think the principle is the same .

[dtango]

I'm not saying you are wrong when you say the two planes will have the same performance at the same weight. You either seem to think that will be a common occurance or (which I think is more likely) you are tweaking Krusty for the simple sake of tweaking him.

I know if someone comes up to me and says "Hey, I'd like to test this bullet to make sure it is ballistically matched with this other bullet" one of the first things I am going to check is the weight of the bullet. I don't give two craps if the two bullets are ballistically matched when bullet A is 4 squares if the standard weight for bullet A is 2 squares. Sure, if both bullets weighed 2 squares you wouldn't have to adjust your aim point, but the simple fact of the matter is they aren't going to be 2 squares.

Granted, that is ballistics and not fancy pants aerodynamics... but I think the principle is the same .

No issues from me with your statements Urchin.  2 squares, 4 squares???   I have no clue about lead stuff flying out of metal pipes with holes in 'em so that's like quantum mechanics to me .
 
But c’mon now, you don't actually expect me to believe that someone who’s intelligent enough to provide expert critique of HTC’s FM, able to dissect & skewer the flaws in them would be so easily tripped up by a couple of charts?  I find that very implausible; therefore, I’ved called Krusty out on it to hold him accountable for future intellectual honesty.  Don't make a claim you can't back up, & don't make lame excuses when you screw up.  Nothing more, nothing less.

[RTHolmes]

I just reread the first page again, and Krusty was absolutely spot on with his anaylsis. tango your 1st post is the one with the flawed logic, as I pointed out. you seem confused over who was correctly "called out" here.

[dtango]

I just reread the first page again, and Krusty was absolutely spot on with his anaylsis. tango your 1st post is the one with the flawed logic, as I pointed out. you seem confused over who was correctly "called out" here.

First logic 101 - an argument that is "absolutely spot on" in it's logic is still wrong if any of it's premises are false.   2nd I was hoping you would sort it out RTHolmes.  I fear chasing White Rabbits down various rabbit holes into aero la-la land but if you must here are responses for your shotgun blast of protests of my flawed logic.

1) The SeafireII is heavier than the Spitfire Mk V.
Using Pyro's words, which is heavier, a pound of lead or pound of feathers?  6622 pounds of Seafire or 6622 pounds of Spitfire Mk V?  Just because the Seafire II could be heavier than the Spitfire Mk V doesn't mean it is at a given instant.  It is called aeroDYNAMICS for a reason because the variables are changing.  Make faulty assumptions about these changing variables at your peril.

2) The CoG is further back.
Please tell me, how does this effect speed or climb performance in our specific case?  Really, I can't think of why moving CG horizontally with respect to the thrust line would make a difference.

3) The SeafireII is draggier (sling points & hook assembly).
I left this one for last because this is the most rabbity-hole of the rabbit-holes .  First the specifics.  Are the sling points removable (the "catapult spools" appear to be)?  HTC could have simply modeled the SeafireII with them off.  Bye-bye draggy catpult spools.  What about the arrestor hook assembly?  The arrestor hook looks like it's stowed and not flapping out in the wind when not deployed.  Could I be wrong?  You bet.

But this is where it really gets good.  Let's say I'm wrong & we do need to account for the drag they add.  Just exactly how much impact would the drag have?  10%? 1%? .1%?  To claim it's wrong because we've left them out of the physics without knowing the quantifiable impact of leaving them out leads us down a path of aero infinite regress lala land.  All our fundamental aero maths are based on reasonable approximations where stuff get's left out all the time.  Just because something is left out doesn't mean we don't have a reasonable approximation.  Otherwise we might as well go back to cave drawings in aero because none of our aero science is any good.

Cheers,

[moot]

Tango if the Seafire and SpitV are no different except for CV eqpt, then aren't the odds on any given SpitV or Seafire you encounter such that the Seafire will be heavier by that small amount?  
Ergo the Seafire's chart ought to reflect it:  The aerodynamics would be the same but the Lead Seafire probably doesn't weigh as much as the Feather SpitV.

I screw around with planes' "default" characteristics when I want to make straight dogfighting (as opposed to historical mission/design) comparisons, e.g. reducing all compared planes' ammo (dump all but 10 kills' worth) and fuel (20min at WEP or nearest MIL/WEP), etc, but that's not what the AH charts are about.  They're about giving the players a gist of each plane's characteristic performance.

And a Seafire is characteristically heavier than a SpitV.  I don't think it's a big deal either way, but where does the above logic's premise go wrong?

[RTHolmes]

if it was a shotgun blast it was a slug, not birdshot

2 planes with the same weight, same engine and similar airframes except one is a little draggier than the other. the cleaner plane will be faster. I cant state it any simpler than that.

how much difference? not alot, my guess <5mph. the 4 sling/catapult points are not big but they do protrude (spindles were screwed into them when required.) the hook does stick out a few inches below the fuselage, right into what should be clean airflow and its wide and shaped like an air dam. the door has a pretty sizeable gap all around it, not great for drag. most of the strengething plates for the fuselage were riveted to the frame on the outside of the skin, not internally. you can see the main datum one clearly - looks like badly fitted car trim line. also round the radio hatch.

[dtango]

moot- I'll get back to you.  Thinking about how to be concise & clear in a reply.

RTHolmes- slug vs. birdshot, what's the difference?  They're both painful!   Just don't shoot me on accident like Cheney, deal?

If you think the Seafire II is draggier, bring some data to HTC to have them change it.  It's one thing to speculate about it, it's another to have the data that shows it.  I'm all for fixing it if you've got it.  You won't find me griping about airplane data .  There's a big difference between that vs. making faulty claims about how the physics FM engine is crappy in my book.