Spitfire mk XIV

[Badboy]

Hi,

I notice that the Spit14 is now free in the MA, so here is how it stacks up against the other Spitfires. The curves in the first diagram show both the sustained turn rate and turn radius based on MOSQ's data, for a two circle fight. The second diagram shows the radius and rate in a one circle fight for just the Spit14 v Spit16.





This next chart compares Spitfire speeds at all altitudes and is based on the speed charts on the ingame clipboard, not flight tests.



Hope that helps.

Badboy

[bustr]

How about including the WEP speed chart?

I'm constantly being dived on by spit16 on WEP from 3k out who seem to have paid the extra $2.95 for the long range airframe identifying radar package. Or all spit16 drivers in the game are still suffering from XIV envy and haven't gotten used to it being unperked and want to show it aint chit. So every spit they see these days is an XIV regardless. The lower the better. The small alt difference starting point very quickly negates any low level speed advantages on MIL and climb advantages on WEP of the XIV. The spit16 climbing on WEP after a shallow dive is an instantaneous vertical 3000ft warp12 crotch rocket.

The XIV is not at it's best trying to respond to such spit16 attacks like the rest of the spit stable is notorious for. Defensively it's a bit more like a pony when caught lower except the pony can still dive away from a spit16 with some air under it. I find the madhatter 16 driver on WEP sticks to the XIV like glue in dive aways or climb aways and turning needs a well practiced overshoot with kill to get rid of the spit16, or it's stuck to your 6. I'm often inclined to return in a spit8 to dispatch the spit16 who seems self appointed to rid the world of XIV.

Since the XIV has been unperked, I've come to appreciate what kind of wonder weapon the spit16 really is in this game. Reminds me of the La7 of old before the graphics makover.

[Bruv119]

Hi Badboy,

we've had some good discussions so far on the limits of the Spit 14's capabilities within our squad and after doing some dueling in it the most frustrating thing about flying the 14 is the crazy torque and overall sloppiness in the stall compared to other spits. 

I appreciate it is designed for speed but in your opinion would you not say that a Spit 14 even with the longer airframe to compensate the extra power should still have a fighting chance against say a 109K4 in a knife fight?

[bustr]

Bruv,

Sardonicism aside, how do you fly your XIV to leverage it's strengths and alleviate it's weakness? Especially with the critical fuel amount that allows it to be flown like a spit8 is very close to the RTB point once you reach it and use WEP a few times.

[Bruv119]

we use our custom arena set fuel to unlimited at 25%  and then knock the crap out of each other.   We can probably do >30 fights in an hour and really push the limits of the aircraft at varying altitudes with air spawns.  

The K4 with its throttle cut slow can still roll against torque but the Spit 14 just will not roll.   The last time I checked it still had ailerons!  

[Badboy]

Hi Bruv119

we've had some good discussions so far on the limits of the Spit 14's capabilities within our squad and after doing some dueling in it the most frustrating thing about flying the 14 is the crazy torque and overall sloppiness in the stall compared to other spits.  I appreciate it is designed for speed but in your opinion would you not say that a Spit 14 even with the longer airframe to compensate the extra power should still have a fighting chance against say a 109K4 in a knife fight?

The Spitfire Mk XIV is certainly different from the other Spitfires, it had a bigger more powerful engine, different propeller, a basic Spitfire airframe with a longer nose and local strengthening, and a bigger rudder to offset the greater forward keel area and revised vertical tail surface. The different configuration resulted in different dynamic stability and it was known for pronounced torque effects at very low speed. It was also known to give less warning in the stall and the different pitch dynamics would have influenced recovery. All that makes it sound like a very different animal. Does all that add up to what you have described? I haven't done enough work on the Spit XIV to be sure, but my initial reaction is that it all sounds right. Not to mention that over the years, I've learned to trust the Aces High modeling, because whenever I've done a full analysis, I've always been amazed at the degree of accuracy. Kudos HTC. 

What that means at the moment in Aces High is that the Spit XIV can still win a flat turn, but the K4 is superior in the vertical and at very low speed. Add that to the fact that we have several generations (in AH terms) of players who have cut their teeth in the K4, and it sounds to me like it all adds up to almost exactly what you have discovered in your squad dueling sessions.

Of course the Me109 v Spitfire match up is of special interest to me (and most British/German players) so I plan to do some more work on this, but based on early indications I'm not expecting any surprises

Hope that helps...

Badboy

[Midway]

Hi Bruv119

The Spitfire Mk XIV is certainly different from the other Spitfires, it had a bigger more powerful engine, different propeller, a basic Spitfire airframe with a longer nose and local strengthening, and a bigger rudder to offset the greater forward keel area and revised vertical tail surface. The different configuration resulted in different dynamic stability and it was known for pronounced torque effects at very low speed. It was also known to give less warning in the stall and the different pitch dynamics would have influenced recovery. All that makes it sound like a very different animal. Does all that add up to what you have described? I haven't done enough work on the Spit XIV to be sure, but my initial reaction is that it all sounds right. Not to mention that over the years, I've learned to trust the Aces High modeling, because whenever I've done a full analysis, I've always been amazed at the degree of accuracy. Kudos HTC.  

What that means at the moment in Aces High is that the Spit XIV can still win a flat turn, but the K4 is superior in the vertical and at very low speed. Add that to the fact that we have several generations (in AH terms) of players who have cut their teeth in the K4, and it sounds to me like it all adds up to almost exactly what you have discovered in your squad dueling sessions.

Of course the Me109 v Spitfire match up is of special interest to me (and most British/German players) so I plan to do some more work on this, but based on early indications I'm not expecting any surprises

Hope that helps...

Badboy

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.

Rate of Roll
19. Rate of roll is very much the same.


Conclusions
23. The all-round performance of the Spitfire XIV is better than the Spitfire IX at all heights. In level flight it is 25-35 m.p.h. faster and has a correspondingly greater rate of climb. Its manoeuvrability is as good as a Spitfire IX. It is easy to fly but should be handled with care when taxying and taking off.

GENERAL CONCLUSIONS

68. The Spitfire XIV is superior to the Spitfire IX in all respects.


http://www.spitfireperformance.com/spit14afdu.html

  

[Bruv119]

that is a very alarming article if it were fact Midway.  Do you have any other sources to support said claims?

With Thrila flying the 14 and me in a 9 he can indeed make a high G / speed turn and match the first turn of the 9 but as soon as the speed drops off for a second / third merge I find myself easily inside his turn.  If he continues to turn after that first merge he is a dead man.   

As for shooting,  it is extremely difficult for the 14 to hold steady for a precise snapshot against a hard manoeuvring opponent and then not be dead in the very next turn. 

I think maybe the torque thing is over done a little and the 109 K4's torque effects too gentle.   

[Midway]

that is a very alarming article if it were fact Midway.  Do you have any other sources to support said claims?

With Thrila flying the 14 and me in a 9 he can indeed make a high G / speed turn and match the first turn of the 9 but as soon as the speed drops off for a second / third merge I find myself easily inside his turn.  If he continues to turn after that first merge he is a dead man.    

As for shooting,  it is extremely difficult for the 14 to hold steady for a precise snapshot against a hard manoeuvring opponent and then not be dead in the very next turn.  

I think maybe the torque thing is over done a little and the 109 K4's torque effects too gentle.  

Why would it not be fact?  This comes from a classified "secret", at the time, June 15 1944 extensive report from a unit of the RAF whose reponsibility was evaluating aircraft at the time for the RAF. http://en.wikipedia.org/wiki/Air_Fighting_Development_Unit

[Slate]

  Perk the Spixteen. For it is faster than a speeding bullet. 

[Badboy]

http://www.spitfireperformance.com/spit14afdu.html

 

Hi Midway

The problem with the information in that report is that it can be interpreted in different ways, and there isn't enough detail provided to know how to interpret it correctly. Without knowing the conditions used during the turn circle experiments, the statement quoted below is worse than worthless from an aerodynamic/scientific perspective, and I'll qualify that in a moment.
 

Turning Circle
18. The turning circles of both aircraft are identical.

For example, suppose the test was begun at 200mph and at 3g... under those conditions almost every allied/axis aircraft will have identical turn circles. There are a wide range of conditions under which you would expect that to be true, and without knowing what was actually done, it isn't possible to tell if they were comparing instantaneous or sustained turns, turns above or below corner velocity or how close to the edge of the envelope they were going, and all of that makes a big difference. It is also entirely possible that they were simulating combat conditions and comparing break turns from cruising speeds for only long enough to determine if a guns tracking solution was possible, if so turning for short periods would not be enough to show any significant difference in turn circles. Considering how rare protracted turn fights were, holding an identical turn circle for as many seconds as it took to fire enough rounds for a kill, may have been all that was needed for the author of the report to make that statement, after all from his perspective it may have been true under the only conditions he felt were worth considering. Without more detail, we can't say.

I said the information was worse than worthless because without sufficient detail to reproduce the results, the report while factual, is not scientific, it is anecdotal. As such it will fuel more arguments than it will settle and is of little value to anyone trying to model the aircraft, or predict its performance.

Hope that helps.

Badboy

[bustr]

I had an opportunity to fly the XIV against a K4 in the MA in a WW2 style encounter. We started from 25k working down to 5k.

This was due to I never allowed us to enter into an AH signature synchronized airshow aerobatics competition. It was an extended series of large descending vertical scissors punctuated with rocketing high YoYo's and low YoYo's. The XIV kept equal pace with the K4 forcing the constant loss of alt due to being able to turn inside at will at the speeds we kept. The K4 could not out climb the XIV from a co E high speed energy fight due to catching rounds in the 400-500 vertical spacing. Thus the constant lowering of the fight level in a series of quick interactions, then either another attempt at a vertical rope, then loosing alt to a descending scissors. The XIV is not a friendly gun platform during aerobatics. Even at speed closing, it can have a gyroscopic mind of it's own path if you need to make a micro adjustment.

The XIV unlike other spits in that vertical moment just before you and the K4 stall and float off. Is not controllable like the K4 to really manage a vector change for a finishing shot. That giant gyroscope in the nose has it's own ideas. It also has a bad habit of stalling flat of it's back and holding you there. Sometimes if I timed it right, flaps just before the stall would make it stall as expected in a spit8. But, as soon as you have it nose down, the flaps have to come up before attempting an increase in throttle or the plane spins nose down with no control authority.

The XIV is a high speed interceptor in WW2 terms. It does everything well at it's designed combat speed range against it's primary advisories the G6 and FW-A family. It was not designed with 1940 acm in mind. The pilot report from 1944 uses combat terms understood by the concerned parties of the time relative to the expected advisaries. In 1944 air combat was not the airshow aerobatical "My kungfu is stronger than your kungfu dancing" we perform in the arenas. While the last Bf109 with regimented piloted testing results numbers was the G14. From what I can find on the Internet, K4 testing numbers were majority engineering projections. The current performance graphs at Spitfire Performance for the XIV and K4 in climb is a lot different than the current AH graph.

Charts of 18lb boost versus 1.8 ata climb.

Source: http://www.spitfireperformance.com/spit14v109.html

[Midway]

Hi Midway

The problem with the information in that report is that it can be interpreted in different ways, and there isn't enough detail provided to know how to interpret it correctly. Without knowing the conditions used during the turn circle experiments, the statement quoted below is worse than worthless from an aerodynamic/scientific perspective, and I'll qualify that in a moment.
 
For example, suppose the test was begun at 200mph and at 3g... under those conditions almost every allied/axis aircraft will have identical turn circles. There are a wide range of conditions under which you would expect that to be true, and without knowing what was actually done, it isn't possible to tell if they were comparing instantaneous or sustained turns, turns above or below corner velocity or how close to the edge of the envelope they were going, and all of that makes a big difference. It is also entirely possible that they were simulating combat conditions and comparing break turns from cruising speeds for only long enough to determine if a guns tracking solution was possible, if so turning for short periods would not be enough to show any significant difference in turn circles. Considering how rare protracted turn fights were, holding an identical turn circle for as many seconds as it took to fire enough rounds for a kill, may have been all that was needed for the author of the report to make that statement, after all from his perspective it may have been true under the only conditions he felt were worth considering. Without more detail, we can't say.

I said the information was worse than worthless because without sufficient detail to reproduce the results, the report while factual, is not scientific, it is anecdotal. As such it will fuel more arguments than it will settle and is of little value to anyone trying to model the aircraft, or predict its performance.

Hope that helps.

Badboy

I understand what you're saying, but I was keying in on a couple of things.  The word 'circles' is plural, so I assume they meant under more than one condition, but you're right, that's not very scientific.  Also, the roll rates being very much the same, seems to indicate there were no material differences that were worth noting.

But the most important part to me was them saying it maneuvers as well as the IX and outperforms at all heights, and is easy to fly.  Our Spit14 does not equal the Spit9 (close turn fights / reversals) in maneuvering, and is certainly the most difficult to fly of all the Spitfires.

So, I'm guessing Bruv is right in that the torque is overdone.  Also the roll rates are probably too slow and it gets too unstable at slow speed turns.  It snap rolls so quickly and violently in either direction by just pulling on the elevators a little too much and with a little bit of rudder either way.

  Badboy


PS: Our MK XIV also doesn't feel nose heavy on taxi.

PSS: I know nothing of what I speak...
... and am just offering my 1st grade elementary school level opinion of what little I think I know.

[Badboy]

The word 'circles' is plural, so I assume they meant under more than one condition, but you're right, that's not very scientific.

Yes, the report mentions that there were tests at different altitudes, but we have no idea what test was carried out or under what conditions so there simply isn't enough information to interpret the statements correctly.

Also, the roll rates being very much the same, seems to indicate there were no material differences that were worth noting.

That's not surprising... same wings, same wing span, same controls, very little difference in the moment of inertia in the roll axis, you wouldn't expect much difference in roll. 

But the most important part to me was them saying it maneuvers as well as the IX and outperforms at all heights, and is easy to fly.

The catch is that in this report when they refer to maneuvering, they are also talking about how well the aircraft responds to control commands in terms of pitch rates and roll acceleration and how the aircraft responded to the controls, not only how well it turned, and there is nothing to quantity it. Also when they refer to performance, they typically mean linear speed or acceleration, not how well it turned, and again, not quantified.

So, I'm guessing Bruv is right in that the torque is overdone.

I would guess otherwise, because the torque can be easily calculated, it is high school physics and depends on the engine and prop configuration. Also the engine and prop data is far easier to find than flight test data so I think it is very unlikely that HTC would get that wrong.

Also the roll rates are probably too slow and it gets too unstable at slow speed turns.

Again, that report doesn't provide enough information to quantify either the roll rates or low speed stability. 

Is the Spitfire Mk XIV correct? As I said before, I haven't done enough work on the Mk XIV to be sure. But one thing I am sure of, is that the report linked to above will be of very limited help. 

Regards

Badboy

[bozon]

Pretty much all of those reports in the style of plane X versus Y are useless.

Example:
"18. The turning circles of both aircraft are identical."
But then they also say the 14 turns worse to the left. So, does that mean that the spit 9 also turns that much worse to the left? They probably played "follow the leader" and eased into a tight sustained turn with some significant speed - nothing like a sudden max-rate turn like we do in the game or fighting the stall at 90 mph and full throttle.

So, I'm guessing Bruv is right in that the torque is overdone.

If anything, the other planes are underdone. As Badboy said, calculating the torque is relatively simple. However, I feel that the way it is applied to the FM is forgiving in some way. I mean, in most normal flight conditions it is fine, but in more extreme conditions, when these effects are important perhaps not. There is absolutely no problem stalling a plane, nose high to near 0 air speed while at full throttle and remain in full control. What exactly counters the torque? the ailerons? with almost no airflow at the wingtips? In some planes it was said that the throttle had to be advanced gradually on the ground to prevent ground loop before there was enough regular airflow on the rudder to counter it. Very few planes develop strong yaw at low speeds and full throttle.

HT once mentioned (I think when AH2 was in beta) that they model the prop wash and how it interacts with the wing-roots. The effect is supposed to counter the torque by increasing the lift on the wing that is being "pushed down" due to prop torque. Perhaps this effect is exaggerated in most FMs (but is modeled weaker in the 14?). Perhaps it needs to be dependent on the flight conditions. Perhaps it is something else entirely. I really don't know. HTC is doing a great job with the FMs, really the best of any flight sim, but modeling all the effects at the extremes of the envelope is far from trivial.