Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: funked on October 18, 2000, 03:08:00 AM
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I took a N1K2-J with 100% fuel and did some climbs using the default autospeed setting. Everything looked OK until I got near 20,000 feet.
Altitude (ft), MIL RoC (fpm), WEP RoC (fpm)
20,000, 2250, 2500
25,000, 1500, 1700
30,000, 700, 850
At this altitude the plane only had about 90% fuel so the numbers might be inflated a little.
But if you check out the official chart (below), the plane should climb the same with MIL or WEP settings above 18k or so. But in my test I found a climb rate increase with WEP.
The difference is not nearly big enough to support some of the fantastic claims by the wh... uh players (like N1K2-J outclimbing P-38L at 25k) but it looks like the arena performance doesn't match the charts.
(http://www.hitechcreations.com/images/charts/n1k2climb.gif)
[This message has been edited by funked (edited 10-18-2000).]
[This message has been edited by funked (edited 10-18-2000).]
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Punt!
So much N1K2-J whining but nobody's interested in facts...
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I am funked. I also know that Pyro may pay attention to your tests, where the general whining has no chance at all. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif) And rightly so.
Thanks for being one of the few who actually took the time to test something instead of just endlessly whining about the perceived problems. Cheers, I appreciate that you took the time to test it. If only more folks would do the same!
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Lephturn - Chief Trainer
A member of The Flying Pigs http://www.flyingpigs.com (http://www.flyingpigs.com)
(http://tuweb.ucis.dal.ca/~dconrad/ahf/lepht.gif)
"My P-47 is a pretty good ship, she took a round coming 'cross the Channel last trip.
Just thinking 'bout my baby and lettin' her rip, always got me through so far."
- Steve Earl
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What about the 1C?
Although Im not sure this particular test would be of any relevance to my observations
about energy retention in the Hog beast.
Im also beginning to wonder if automatic trim is playing any role in enhanced energy retention in extended high G manoevers. Especially at high altitude where the air is....you know......thinner.
Just a thought, a silly thought.......
Lep, whats the best method for testing energy retention? Is there any material pertaining to the real ships for cross referencing?
Yeager
[This message has been edited by Yeager (edited 10-18-2000).]
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Any reason not to do these tests in the TA where fuel burn is not an issue?
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Mino
The Wrecking Crew
"Anyway, more golf..."
Humble
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TA? He would have done them offline at 1:1 fuel burn Minotaur...
Yeager, pick a speed, pick a G load, pull flat 360º turns and read the exit speeds.
FWIW: The -1C climbs about 100fpm better than the -1D. Third time I've posted that now.
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Juzz, what Mino means is that the TA uses a really tiny fuel multiplier (like .01) so that fuel burn is negligible. I'll do that, but if the results are more than 5% different I'll eat my hat.
But the problem here is that the N1K2 is getting extra thrust from WEP above 18k when the charts say it shouldn't. That result wont change.
PS One reason to use a realistic (1.0) fuel multiplier is that the result will be comparable to real life flight tests. They didn't have fuel multipliers in real life, and they sure as hell didn't tow the N1K2 up to 20k then start the engine to get a climb speed reading. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
Yeager, Wells has already dealt with the energy retention subject in detail. It seems you breezed through the thread in question without noticing this so you might want to read it again: http://bbs.hitechcreations.com/smf/Smileys/default/Forum1/HTML/005416.html (http://bbs.hitechcreations.com/smf/Smileys/default/Forum1/HTML/005416.html)
[This message has been edited by funked (edited 10-19-2000).]
[This message has been edited by funked (edited 10-19-2000).]
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Yeager,
I would test depending on what you want to demonstrate. If you want to test 180 degree flat reversals or 360 degree turns, that will give you some idea about energy retention in maneuvers. What wells has done is great stuff, but I think some testing on how much speed is lost in a flat turn would be useful.
The setup is the tricky part, but here is one suggestion:
Log into the TA.
Grab a plane, 100% fuel, most common ordinance load, but clean config.
Pick a big flat area with some visible landmarks, a 0 alt. main base works well.
Stay within 1k of the ground, a few hundred feet is better, as close as you can.
Trim the aircraft to a particular speed that all of the aircraft you test can reach in level flight, say 250 mph.
Line up with a landmark, then turn 360 degrees pulling a constant G load, say 4 G's, or whatever is most appropriate.
Record the times to make that 360 and the exit speeds.
FILM the tests so you can show Pyro if you find something. Also, you could skip recording any numbers in the tests this way, and just go back and look at the film after if you like. The film updates may not be fast enough for the accuracy you need though.
You could do these tests with and without combat trim if you have time, or just one way as long as you are consistent.
BTW, about the fuel multiplier issue. Your 1:1 fuel multiplier is not really correct. These planes would fly for MUCH longer in the real world, we burn fuel much faster in AH to account for the terrain being smaller. It has to be this way or it would take to long to find a fight. We can't have 5 hour combat sorties in the game. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif) I'd test in the TA to eliminate this issue all together. In addition, this way the tests are done online, so it's real in-game conditions with the real host instead of using the client side mini-host.
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Lephturn - Chief Trainer
A member of The Flying Pigs http://www.flyingpigs.com (http://www.flyingpigs.com)
(http://tuweb.ucis.dal.ca/~dconrad/ahf/lepht.gif)
"My P-47 is a pretty good ship, she took a round coming 'cross the Channel last trip.
Just thinking 'bout my baby and lettin' her rip, always got me through so far."
- Steve Earl
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Lephturn, unless something has changed (in 1.04) the terrain scaling and fuel burn rates at full throttle settings are dead on (somewhat off at reduced throttle settings, according to Funked).
The terrain is built so that 1 mile in the terrain corresponds to one "performance" mile in the aircraft.
And the fuel burn multiplier works as advertised.
IMO the reason it feels to most people like our planes dont' fly as long as the real ones, is two factors.
The 1st is the obvious one, the fuel burn multiplier.
The 2nd is that in RL pilots used cruise settings to extend mission ranges, while in AH 90% of the people firewall the throttle and leave it there (oh except for the times they hit WEP (http://bbs.hitechcreations.com/smf/Smileys/default/wink.gif) ).
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Vermillion
**MOL**, Men of Leisure
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Yep, cruise settings are waaaay porked. For example at the maximum continuous cruise setting for the Lancaster; 2650 RPM and +4lbs boost - the aircraft just falls out of the sky. It's supposed to be doing about 230mph! (http://bbs.hitechcreations.com/smf/Smileys/default/frown.gif)
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FWIW measuring speed lost or altitude lost is the same thing. Energy is energy. So whatever is easiest for the test pilot is the way to go.
The beauty of Wells' method is that you are measuring the energy loss in a steady-state situation instead of a transient maneuver like the 4g turn at a constant altitude. So if you want to compare with a theoretical prediction, you only need a steady state model, which you can do with pencil and paper, instead of a transient model which means you have to build your own sim. Also you can record your data over a longer period, reducing error.
[This message has been edited by funked (edited 10-19-2000).]
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To back up what Verm said, it's the fuel burn rate multiplier that is causing the reduced endurance in the Main Arena. The multiplier is not set to 1.0, it's set to 2.0 or 2.5. If you set it to 1.0 the endurance at full throttle is pretty darn close to the real deal.
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BTW Thx Lephturn. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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Sooooo, that GEORGE has cheaty-boost WEP over 18k, eh? Hmmmm... (rubs chin)
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Off topic a little. Here the results of my testing performed for the P-51D.
I tested in the TA with 100% fuel, no DT's. For Wep testing, I lowered altitude 2k after Wep quit. I let the Wep reset fully, then re-engaged Wep to obtain data pionts.
Actual Mil and Wep climbrates
(http://my.ispchannel.com/~jfaries/p51dmilwep.jpg)
Actual Wep vs AH Wep (chart) climbrate
(http://my.ispchannel.com/~jfaries/p51dvschart.jpg)
AH Chart for P-51d climb
(http://my.ispchannel.com/~jfaries/p51d-ah.jpg)
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Mino
The Wrecking Crew
"Anyway, more golf..."
Humble
[This message has been edited by Minotaur (edited 10-19-2000).]
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You're right Funked. The current George chart is out of date because I made some changes to the low alt performance back in the beta and never updated the chart. However, there still should not be a wep boost at that altitude and yet there is. I don't know how that got there so I'll have to do some research in our version control to see what happened. I'll make some time before this next version to check the web charts against the game and get things the way they're intended.
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Doug "Pyro" Balmos
HiTech Creations
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Wow... did you guys see that!
All whiners please take note. Funked just demonstrated how you actually get a change made. He did tests and posted the results, and Pyro responded right away. Cool huh? Just think about all the things you could get changed if you use your time testing instead of writing BBS posts! (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
<S> funked.
WTG Pyro and HTC for being the most responsive game developers I've ever heard of.
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Lephturn - Chief Trainer
A member of The Flying Pigs http://www.flyingpigs.com (http://www.flyingpigs.com)
(http://tuweb.ucis.dal.ca/~dconrad/ahf/lepht.gif)
"My P-47 is a pretty good ship, she took a round coming 'cross the Channel last trip.
Just thinking 'bout my baby and lettin' her rip, always got me through so far."
- Steve Earl
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Mino, what are the Y and X axis representing? Best I can figure is climbrate in ft/min divided by 10. The X axis is altitude. My experiences in the p51 would tell me that this is the case. With 50% fuel I can climb out at about 3400 fpm, which rapidly drops to about 2800 fpm at 10k. At 20k I can climb at about 2k fpm.
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bloom25
THUNDERBIRDS
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Thanks Pyro!
<S> Leph. (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
Cool charts Mino!
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Question for a few of the mathematical folks out there:
The Butterfly flaps on the George are AFAIK an automatic combat flap system that engages when the lift over the wing drops- correct?
Now we know this is represented in the model but what I am wondering is how much extra drag those flaps are going to creat per wing.
The data on it I have indicate that the flaps engaged when lift dropped under X amount, I figured in some testing I was doing on flat turns that when speed in the turn came to the point the flap extended the plane would start decelerating at a different rate. Since the info I have indicate it extended at mid to low speeds I figured the rate would change around 250-200 mph.
However I cannot find the change! In flat turns at 3G SL the rate of deceleration is constant to stall. Can the flap really not affect the rate enough for us to pick it up?
ALSO: I see some oddities in how high AOA is being treated in regards to drag. I cannot pin it down but some things are happening I don't think are correct. I put some planes into high angled zooms to see how they handled E retention in zoom climbs and sometimes it wasn't working. The A6M5 is a best example: the plane can hold itself at 37 degrees and achieve <1000 fpm at around 92mph. I did not think any WWII plane could generate enough thrust to hold itself at this angle. However most of the good E retention planes in the game can literally hold a semi cobra position right up until stall speed. BTW I measured by going to external view, putting a ruler along the rear horizontal stab and prop hub and a protractor on the water horizon. Some planes need to be going quite fast to get them into position- then hit auto angle and see where they will stay stay flying.
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Sorrow,
I don't think those flaps are modelled. Last time I checked, you had to put them down yourself. that might have changed though...was a few versions ago. At stall speed, you can add a good 15 degrees to the climb angle. If you are measuring 37 degrees pitch angle, the climb angle is probably more like 20.
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Originally posted by wells:
Sorrow,
I don't think those flaps are modelled. Last time I checked, you had to put them down yourself. that might have changed though...was a few versions ago. At stall speed, you can add a good 15 degrees to the climb angle. If you are measuring 37 degrees pitch angle, the climb angle is probably more like 20.
The manual flaps don't help turning signifigantly. They do add drag however.
Those wing flaps were pretty big. Anyone got a aspect shot above the N1K2? In AH, the flap hinge on the wing only comes half as high as the alieron hinge...it should be the other way around if, I remember right. They trailed off the wing when deployed fully, like the Stuka's alierons set up, or for a modern example, the 747's flaps. That is, however, within AH.
- Jig
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Originally posted by bloom25:
Mino, what are the Y and X axis representing? Best I can figure is climbrate in ft/min divided by 10. The X axis is altitude. My experiences in the p51 would tell me that this is the case. With 50% fuel I can climb out at about 3400 fpm, which rapidly drops to about 2800 fpm at 10k. At 20k I can climb at about 2k fpm.
Oops sorry, I should have pointed something out.
Bloom, it is climbrate divided by 10. This is so that I can get all the data, from 0 to 30k altitude, all on one page of my spreadsheet.
I stated my testing conditions above the top chart. They were 100% fuel, no DT's with the test being done in the TA.
To read my chart turn the HTC chart sideways or vice versa.
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Mino
The Wrecking Crew
"Anyway, more golf..."
Humble
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Mino, one thing about 51 is that full fuel is an overload condition. In AH, it's set up to have full wing tanks at 75% and no fuel in the fuselage tank. So the normal gross weight would be at 75% and that's what the chart will correspond to.
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Doug "Pyro" Balmos
HiTech Creations
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Originally posted by Pyro:
Mino, one thing about 51 is that full fuel is an overload condition. In AH, it's set up to have full wing tanks at 75% and no fuel in the fuselage tank. So the normal gross weight would be at 75% and that's what the chart will correspond to.
As it is though, at 75%, the wing tanks are full, and 25% is in the fuselage tank. Which should be perfectly alright, because once the fuselage tank has been half-emptied, the CoG issue is corrected. (Least that how I remembered it)
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Originally posted by Pyro:
Mino, one thing about 51 is that full fuel is an overload condition. In AH, it's set up to have full wing tanks at 75% and no fuel in the fuselage tank. So the normal gross weight would be at 75% and that's what the chart will correspond to.
Pyro;
I was not really doubting your chart vs actual performance. I was more just checking the relative curves between the two graph shapes. I found it interesting, that is all.
What I did not say, but quite please me, was how well the curves matched up. My curve is a little wavy in places. I only did the test once, where I should have ran it a few times and averaged my data. The VSI can be difficult to read accurately. I can only break it down into 50fpm increments.
My assumption was that somehow I had ran the test under different conditions and for my test the plane heavier than yours on the HTC climb chart.
Thanks! (http://bbs.hitechcreations.com/smf/Smileys/default/smile.gif)
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Mino
The Wrecking Crew
"Anyway, more golf..."
Humble
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You're right Jigster. Back in the beta I had it set up as I described because the 85 gallon fuselage tank was later placarded to a max of 45 or 55 gallons. That was a postwar stipulation so I changed it back to 85 gallons in the beta.
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Doug "Pyro" Balmos
HiTech Creations