Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: spitfiremkv on March 28, 2002, 05:43:27 PM
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the spit 14 is much more prone to stalling and spinning than the previous versions.also,when my engine quit while flying low and slow the nose went down and i couldn't pull up at all...does anybody know why it flies so differently?
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Heavier, more torque...
SKurj
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you're right...that sucker is much heavier than the other spitfires.still,it's a good b&z and can outturn with almost everything except his own brethrent,hen the zero,the hurricane...and sadly the 109. That's at low altitudes.
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Which 109?
As it is, from my little bits of testing, I'd say the Spit14 turns a bit worse than 109F-4, bit better than Yak-9U. 109F-4 out turns a Typh, but Typhs out turns the 109G-2 and G-6. (In the long, sustained turns of 3~4 circles or more) I think the Spit14 turns a bit better than Typhs.
So in comparison with 109s:
E4>Spit14
F4>Spit14
G2 G6 G10
The Spit14 turns better than all other planes that go over 400mph, too, deck or at alt.
True, it does tend to become unstable when it sustains turns under 250 mph, but all 109s are much more unstable under 250mph except the E4(even the F4 starts to wobble under 250mph).
If you are out turned(flat, sustained turns) in Spit14s by any other 109s than E4 and F4, you're doing something wrong.
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Remember, the Spitfire XIV turns tighter to the left than it does to the right. This is opposite of Merlin Spitfires, which turn tighter to the right than they do to the left.
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This true in AH Karnak?
SKurj
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interesting point there karnak. so if i turn left i should be able to outturn the other spitfires...hehehe,good to know. call me a dweeb but i just love turning dogfights. i can't even shoot straight anymore, only with lead deflection :)
from personal experience, i'd say spit14 definitely outturns tempests on the deck, but the temp is much faster at low altitudes. in the specs i noticed the temp and typh reach their maximum speeds at lower altitudes than the spit, so it makes sense.
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Skurj,
Don't know. I haven't tested it. That is what it did in reality though.
I did test its roll rate in AH, it definately rolls faster to the right.
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Tested it.
AH Spit14 turns considerably better to its left than right.
Now, all planes which had to deal with torque had turn rate differences I presume, but the AH Spit14 seems to be the only plane in AH I've tried that the turn rates of left and right is different enough to be noticed.
...
but really shan't expect a Spit14 to out turn other Spitfires - left or right. Methinks you're rating the Spit14 a bit high there, spitfiremkv.
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I tested the Spit14 agains other models in combat and it can definitely turn with them to the left. It stalls much quicker if I turn to the right. I don't expect it to outturn them-after all it's a much heavier plane, retaining the same overall dimensions and so it has higher wing loading and higher stick forces.
The Griffon sure generates a lot of torque ( did u see it try to roll on the ground when u apply full power on take off? :) )
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Strange that it tested out that way, because Karnak has it backwards.
The majority of planes turn better to the left, because of the rotation of the engine.
The Typhoon and Yak-9U however are the opposite and turn best to the right. The Spit XIV should also turn the best to the right.
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Verm, are you sure you don't have it backwards from what the others do? I think you're looking at it from a different angle (direction is relative to where you are).
On most aircraft, the propeller rotates clockwise (from the perspective of being in the cockpit). Rotating in this direction, it should cause you to turn better in a right turn (again, from the perspective of being in the cockpit).
However, if you were in front of the plane looking at it, this would then seem as if it was a left turn so it all depends on perspective.
J_A_B
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If there is something fishy in tests, it's probably the effect of combat trim.
I don't know the exact reason, but combat trim conditions make turning to one's right side in a tight turn(tested sustained turns at 240mph, altitude change + or - 500 feet) very stall prone in Spit14s. I don't think I can match adequate conditions to simulate a trust worthy turn rate test, but I think it's safe to say despite the absolute factor in turn rates may(or may not) favor right turns in Spit14s, one thing for certain is turning to the right in Spit14 is definately a lot harder.
Better test some more..
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Verm they have it right, the spit14 should turn better to the left than the right.
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Quotes from the AFDU Tactical Trials:
TACTICAL COMPARISON WITH SPITFIRE IX
Turning Circle
18. The turning circles of both aircraft are identical. The Spitfire XIV appears to turn slightly better to port than it does to starbord. The warning of an approaching high speed stall is less pronounced in the case of the Spitfire Mk XIV.
COMBAT TRIAL AGAINST FW.190 (BMW.801D)
Turning Circle
41. Spitfire XIV can easily turn inside the FW 190, though in the case of a right-hand turn, this difference is not so quite pronounced.
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One question about torque effects on turning.
How exactly does this influence turning?
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The spit XIV had a 5 bladed prop. Had to use something to absorb the HP from the bigger engine.
Yaw or rudder torque, commonly associtaed with taking off, was caused by a slipstream that would impact the rudder on one side but not the other. Big bladed props caused this more than anything else, other than too small a rudder/vert stab.
When the Spit XIV slows down, it has two probs:
The extra weight of the higher HP engine AND the added/combined effects of higher slipstream torque, plus the normal torque effect of the engine.
Therefore: much more snappy
But not if you turn the engine down!
Try it! Try the same tests with engines turned down somewhat.
The Double Torque effect really hurts it.
.02
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I thought the Griffon rotated opposite from the Merlin?
If it rotates the same direction, then your correct and its too the left.
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This started to bug me, and it would kill me to be wrong on something as simple as this ;)
From "World Enclyclopedia of Aero Engines", by Bill Guston
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The Griffon had cyclinders of Buzzard/R size (6x6.6 in, 2,239 cubic inches) and started off with a lot of Merlin experience built in; yet for most of the war Lovesey managed to keep the Merlin ahead, especially at altitude. The Griffon never equalled the Merlins specific output, but was nevertheless a fine engine, which transformed the Spitfire and Seafire (not least in rotating in the opposite direction, which reversed take-off procedures, though this attribute disappeared with contraprops which were common on the Griffon). Later marks gave around 2,000hp up to at least 20,000ft, maximum power being 2,540hp though in some racers........
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Realize that aircraft turn best in the direction that the torque of the engine pulls them. Because if they're turning in the opposite direction at very low airspeeds (ie near stall speed) the torque of the engine can flip the aircraft over and cause a stall.
Now go into the arena offline and do this simple test. Turn off auto takeoff and combat trim. (I just did this btw)
Load up a Spit IX, start the engine and don't touch the rudder pedals. You will veer to the left. Spit IX's (and all Merlin Spits) turn the best to the left.
Load up a Spit XIV, and repeat the test. You will veer to the right. Spit XIV's will turn the best to the right.
This can also be tested by doing consecutive 360 degree turn tests (no altitude gained or lost) in each direction with a stop watch and average the time results for each direction. But I didn't feel like spending an hour on something when I know what the results will be anyway ;) Seriously, if it doesn't work that way, something is really wrong with the Spit XIV fm.
I've been out of town this past week and today was the first chance I'd had to fly the XIV. All I can say is "WOW!", and boy am I glad this plane is perked. It would quickly become "Spitfire High" otherwise (hell it almost is already :p ). It turns as well as a Spit IX, builds energy like a bat on fire, and I didn't notice anymore adverse torque effects or high speed handling problems. Fly this plane like a E fighter, and there's nothing in the arena that can touch it 1 v 1. Not the Tempest, not the F4U-4, and none of the nonperk planes. The only problem you could possibly have with it, is if you get right down on the deck being chased by multiple La7's and you just let them run you down. If its just one or two, you can turn fight them and win easily. But then again, I'd just make sure I stay above 5k where the Spit can outrun them :)
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Looking from the cockpit the Griffon rotated CCW, the Merlin CW. The Griffon weighed ~300lb more than the Merlin.
The Giffon put out ~4700lb-ft of torque.
A net search will turn up many sites for both engines.
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Hmm, Verm is right about how they behave in AH....
With planes like the Spit 9 or P-51, if you're taking off or in flight the torque will cause the aircraft to roll left.......yet the propeller itself spins to the right...
What I want to know is why. If a plane's propeller is rotating right (clockwise), why should it cause a plane to turn LEFT. This was not what happened with R/C airplanes I've built--they always wanted to go in the direction that the prop was spinning, not the opposite.
In addition, as Karnak's real-world comparison's show, the aircraft supposedly performed as one would expect them to; that is, the Spit 9 turned better to the right and the Spit 14 turned better to the left.
Something wierd seems to be going on. Anyone care to try to figure it out?
J_A_B
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Verm,
I don't know which way it should turn better, only that in reality the RAF concluded that it turned better to the left.
Yes, it is a monster and I would fear no other aircraft in AH in one. The problem is that it always, like all perk planes, gets gangbanged. This if fine if they're below you, you can keep them below you at all times. It isn't fine when they show up above you. At that point you can't use you're climbing ability to get out and unlike the Tempest or 262 you can't dive away either, you're just not fast enough. The F4U-4 and Ta152H-1 share this problem.
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Originally posted by J_A_B
will cause the aircraft to roll left.......yet the propeller itself spins to the right...
What I want to know is why. If a plane's propeller is rotating right (clockwise), why should it cause a plane to turn LEFT.
J_A_B
It's because to turn to the right, the prop axel needs to hold itself to something. It's like if you put on a pair of rollers and help yourself to move foward by pushing on the wall. If you do the same thing but the wall is on wheels too, the wall will move backward and you foward.
This "backward movement" translates on the plane as an opposite rolling tendancy that you need to counter with your controls.
Torque is not the only think who makes the airplane want to roll, u have stuff like Pfactor, gyroscopic forces and the spiraling slip stream.
(http://home.cfl.rr.com/rauns/sig-frenchy1.jpg)
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At that point you can't use you're climbing ability to get out and unlike the Tempest or 262 you can't dive away either, you're just not fast enough.
I yet didnt fly the XIV, but Karnak i dont believe that, i did a comparative divetest once between tiffie, spit IX and FW190D9.
Both RAF fighter never compressed - even after near vertical dive from 20k - nor did they show any stress or control authority loss.
If the XIV shows the same diving chracteristics in AH like the IX, you can just push the nose down, let urself get to 500+ IAS and run away without any compression or control authority loss.
Edit: I did a quick XIV dive test, and i managed to compress it. It started at about 440 IAS at 15k and at 10k it will shake till speed falls under 505 IAS. With those speeds and the accel shown in the dive, the Spit XIV will be one tough plane to catch.
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Naudet,
I was speaking to the realities of the AH MA, where you will not be diving from 20,000ft to escape. If you are at 20,000ft, you're not in a fight and don't need to dive.
In AH you'll have maybe 5,000-10,000ft below you. The Spit XIV can dive extremely rapidly and will escape from most aircraft that way, then it has to level out and many aircraft (La-7, P-51D, P-51B, Typhoon, Fw190D-9 and Bf109G-10 {Yak-9U?, La-5FN?}) will run it down because they are faster in sustained fights.
If the fighter in question is diving from a significantly higher altitude even the great diving ability of a Tempest won't get you out of danger.
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just tried the 14 first time.
I was chased by several planes at low alt (ground was 4k) among them a 190 whom i belive was a D9 (cant be sure though). the dora closed till d800 co-alt while I was in a shallow climb 1kFTS wep on. at those conditions it couldn't catch up.
Bozon
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They way they fly in AH is the way they fly in real life in regards to torque and the other rotational effects. I'm not sure where the report that Karnak has came from, but its opposite of the historical information I've read.
Karnak, yes you get gangbanged/Suicide chased in it just like every other perk plane. Thats just the fact of a perkie. I think you would agree that it should be perked though, or it would rapidly take over the entire arena.
If you get caught with less E by enemy follow on planes, just do what you do what any BnZ plane caught in that situation has too do. Make the enemy commit to the attack and miss, equalize the energy over several gun passes, then disengage with your superior speed and acceleration. And with the turning ability of the XIV it should be relatively easy to make them miss their first few passes.
And while its true there are a few planes faster on the deck than the XIV, you only have to keep a few thousand feet under you, and your just as fast. If you dive away, you don't have to dive all the way to the deck. Keep a hard deck of 4k to 6k and you should have no problems what so ever.
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Karnak, the point about diving is not really the top speed once leveled, but the control at hi speeds. With a 190D9 I'm able to catch by speed a typh in a dive, but no way at all to follow its manouvers at these speeds. While the typh will make a hard turn at these speeds, the Dora will keep shaking and with almost no control at all. Same with spits.
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just as an interesting fact- a Spitfire survived a Mach .91 dive...well,not in mint condition but still flyable. So the fact that it performs well in a dive and isn't affected by compressibility is not an overlook from the programmers of the flight model.
Once again, Spitfires rule!!!!!!!
:D
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Originally posted by spitfiremkv
just as an interesting fact- a Spitfire survived a Mach .91 dive...
Interesting indeed as spitfire never achieved such a speeds nor did P-51s & P-47s. Near speed of sound propellers starts to act like a speed brake.
"Despite having a propeller that was designed to be more efficient at these speeds, the fact remained that the drag rise across the prop was so great that it functioned like a giant disk shaped air brake. Fisher had proved beyond any doubt that all previous claims of exceeding the speed of sound while diving a prop driven aircraft were untrue. There is little doubt that the pilots who reported speeds in excess of Mach 1 were honestly and accurately reporting what they has seen on their air speed indicator. However, due to the extreme rate of descent, the pressure differential in the static pressure airspeed indicator lags far behind the actual altitude of the aircraft. Air speed indicators of the era were not designed to cope with descents that could exceed 40,000 feet per minute. This difference between outside pressure and that within the system would indicate wildly ambitious speeds. These pilots had simply been fooled. When we stop and consider that the ultra-sleek P-80A Shooting Star jet fighter was never able to exceed Mach .94, how can anyone believe that a prop driven fighter could even come close?[/b]
P-47 achieved mach 0.83.
Check here (http://www.hitechcreations.com/forums/showthread.php?s=&threadid=26479)
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Originally posted by spitfiremkv
just as an interesting fact- a Spitfire survived a Mach .91 dive...well,not in mint condition but still flyable. So the fact that it performs well in a dive and isn't affected by compressibility is not an overlook from the programmers of the flight model.
Once again, Spitfires rule!!!!!!!
:D
It was anything but flyable. The prop shaft failed under the dynamic drag loading at around Mach 0.85, and departed the aircraft. That is the only reason it reached Mach 0.91. Moreover, the aircraft had suffered considerable structural damage and I believe it was scrapped on the spot. It's a tribute to the pilot that he survived the dive at all.
My regards,
Widewing
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As far as i know, the fastest Spit managed only mach 0.89 in a dive, and from it the entire power egg (eng+prob) ripped off.
Was some kind of reconaisance spitfire. Have the book not at hand, but will look tomorrow.
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Verm,
Oh, I absolutely agree that it needs to be perked. Free, it'd ruin the MA.
The tactics you describ are why I'd never be afraid of another AH aircraft in it, regardless of our relative start positions.
I'm just not good enough to use those tactics on 10 aircraft at the same time.;)
The Spit XIV also has one major disadvantage, it has the shortest legs of any perk plane, edging out the Tempest if I am correct.
MANDOBLE,
I rarely, very rarely, find fights at altitudes where I can reach those speeds in a dive. Most of my XIV losses have been below 10,000ft, sometimes below 3,000ft. I think I was being to agressive, but as I can only afford one now, I'm being very, very cautious.
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Most every plane in AH turns better to the left than the right, it's more noticable at high power setting and with the high torque engine planes.
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Karnak, I'm talking about 400mph or more, you only need a base of 300mph and a room of 5000 feet to achieve that.
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I veery much like our new shiny Spit XIV but this baby someday...
(http://utenti.fastnet.it/utenti/caporelli/spitmk14-1.jpg)
"A high speed low pass of a FR Mk.XIV E variant during the 1995 Ambrì Air Show"
8-)
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I'm just not good enough to use those tactics on 10 aircraft at the same time
LOL! Karnak, don't feel alone, because neither am I. :)
But its just the nature of the MA furball, and the nature of enemy perkies. Like moths to the flame!!
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AH needs He-177 !
(http://www.kolumbus.fi/staga/he177/orig_he177_a5.jpg)
Greetings Ammo :)
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widewing, when i said flyable,i meant that it managed to land and the pilot didn't have to bail out. that's a big feat, cause a P38 would have ripped into small unrecognizable pieces at that speed. However, I wonder how accurate the Mach-meter on that Spit was.