Hurricane & Spitfire control characteristics

[NZtyphoon]

According to test pilot Jeffrey Quill:
"By this time I was bitterly blaming myself for not having thumped the table much harder about the aileron problem...in May 1938....However production problems at the time made any design changes almost impossible to embody.

The aileron problem was further compounded by what could be described as 'non-repeatibility' or variations in manufacturing accuracy. On first take-off a new production Spitfire would usually be found to be flying severely one wing low, sometimes to the extent that it was almost a two-handed job to hold it. The aircraft would immediately be brought in to land and a trimming strip, comprising a piece of cord sewn inside a length of fabric, would be attached to the upper trailing edge of the aileron on the 'wing low side'....Usually, but not always, if the aircraft had been successfully trimmed at cruising speed it remained in trim at very high diving speed. But sometimes it would develop a strong bias one way or the other. In these circumstances an aileron had to be changed and discarded or tried again on another aeroplane. Thus very small production variations in the hinges, the slotted shrouds in the wing, the profile of the aileron nose balances and the aileron profile aft of the hinge could have a spectacular effect on the lateral handling of each production aircraft.

So the ailerons virtually had to be individually 'tuned' by the test pilot (who had to know what he was about) and it usually took several flights to achieve this. Sometimes if an aileron had been discarded as untrimmable on one aeroplane it could be refitted to another....If, however, after delivery to the Service, an aileron was changed, the whole matching process was destroyed and the aeroplane might fly very badly indeed. There were frequent reports from squadrons of so-called 'rogue' aeroplanes and it usually transpired that an aileron had been changed or that someone had monkeyed about with the trimming arrangements.

The reports which floated into the A & AEE and RAE through HQ Fighter Command on these so-called 'rogue' aircraft did much to confuse the issue during our early efforts to deal with the problem. Provided the ailerons were correctly 'tuned' and the aeroplane correctly flown, there was only one central problem - the ailerons were much too heavy at speed." (Jeffrey Quill Spitfire: A Test Pilot's Story John Murray, 1983, pp. 180-181)

The reports shown by Kurfurst in his second and third postings are some those reports of 'rogue' aircraft as described by Jeffrey Quill, and are not representative of a properly trimmed Spitfire with fabric ailerons, so they should not be used to change the flight characteristics for the game.

Originally Posted by 41Sqn_Stormcrow

Mh. I have some concerns if the report should be taken as a basis for FM development.

It clearly says that the authors of the report have some doubts about their finding as it does not entirely fit with reports from pilots.

The very first page says that both the Hurricane and the Spit were reported to be heavy on ailerons at high speeds while the Hurricane was measured to make the bank of 90° in 2 secs while the Spit's roll rate was measured to 8sec. It is obviously a discrepancy between pilots' complaints about the heaviness of BOTH aircraft and the measurements made on two individual aircraft with one being considerably lighter than the other.

The authors encouraged to contact Fighter Command in order to find out if the Hurricane used for measurement was too light or the used Spit too heavy.

I think this report is not a good base for any FM modelling and more consolidated data is needed.

Spot on - to take these reports as being typical of the flight characteristics of the Spitfire or Hurricane is drawing a very long bow.

Quill went on to write:
"I have mentioned how badly I felt about the ailerons of the Spitfire at the time of the Battle of Britain. In October 1940 I flew a captured ME109E; to my surprise and relief I found the ailerons control of the German fighter every bit as bad, if not worse than, at high speed as the Spitfire I and II with fabric-covered ailerons. It was good at low and medium speed but above 400 mph and above it was almost immovable. I thouught the Me 109E performed well, particularly on the climb at altitude, and it had good stalling characteristics under g except that the leading edge slats kept snapping in and out; but it had no rudder trimmer, which gave it a heavy footload at high speed; while the cockpit, the canopy and the rearward vision were much worse than that in a Spitfire." (183)

[Crumpp]

it had good stalling characteristics under g except that the leading edge slats kept snapping in and out;

That is a rather unusual statement.

The leading edge slats snapping in and out is what gives the Me-109 its very good stall characteristics and virtual immunity to spinning.

[fruitbat]

Originally Posted by Crumpp

That is a rather unusual statement.

The leading edge slats snapping in and out is what gives the Me-109 its very good stall characteristics and virtual immunity to spinning.

With respect, I'll take Jeffrey Quill's opinion over yours all day long.

Just finished reading 'Spitfire, A Test Pilots Story' by Jeffery Quill, and is is a very good read.

[Osprey]

Originally Posted by Crumpp

That is a rather unusual statement.

The leading edge slats snapping in and out is what gives the Me-109 its very good stall characteristics and virtual immunity to spinning.

When they snap in and out they snatch the air on the stalling wing and make the aeroplane harder to handle at those border speeds. This is well documented from test aerobatic flights. This at low speeds and heaviness at high speeds meant that the 109 was not good aerobatically, or rather far worse than the Spitfire.

"Immunity to spinning" - brilliant Biff, I guess you learned that type of engineering quote from your records of early 20th century shipbuilding and will stick with it. "She is unsinkable sir"

[VO101_Tom]

Originally Posted by Osprey

"Immunity to spinning" - brilliant Biff, I guess you learned that type of engineering quote from your records of early 20th century shipbuilding and will stick with it. "She is unsinkable sir"

There are aircrafts, which more difficult to take a spin, especially the school planes, for example. It is known, if you can maintained the airflow on the wingtip, the aircraft remains stable even near to stall speed, with high angle of attack. Furthermore, very difficult take a spin. The assets of the air flow maintaining the leading edge flap and the mechanical and aerodynamic wing twist...

[Osprey]

Originally Posted by VO101_Tom

There are aircrafts, which more difficult to take a spin, especially the school planes, for example. It is known, if you can maintained the airflow on the wingtip, the aircraft remains stable even near to stall speed, with high angle of attack. Furthermore, very difficult take a spin. The assets of the air flow maintaining the leading edge flap and the mechanical and aerodynamic wing twist...

Oh yes of course. Likewise there are ships that are harder to sink than others, but none are unsinkable nor is the 109 immune from spinning.

@Manu, I know what slats are for but regardless of that when they pop out the wing snatches. In a sustained move I suspect that this is useful for an aircraft with such a high wing loading, but in sudden moves I wouldn't expect it to make things smooth and predictable. Don't ask me though, just read pilot accounts and test flights, there are plenty of them. As for the Spitfire, the wing design stalls at the roots before the tips so it is very controllable. The Spitfire is a far superior aerobatic machine to the 109, you'd have to be a fanboy not to realise that. If I picked my moment everytime I'd rather have the 109 characteristics, but you can't. What then? Would you prefer to move better if you cannot run? Ceteris Paribus the Spit has more important advantages, without diving away and not fighting at all that is.

[von Brühl]

None of them say that when the slat deploys it makes it less manueverable like you suggest, nearly all of them state its the bang that makes it an unsettling experience.

I suggest you guys back off Osprey, clearly he's still in a state of aggravation from the Spit II's FM's being brought back to reality, further degradation of the wonderful properties of the Spitfire are just a bit to handle right now, especially since it seems that the devs backed the Spitnerf with a bit more oompf to the 109.

I can remember flying against Osprey on ATAG, he's an excellent pilot, any time he got shot down, was simply due to undermodelling the Spits and Hurri's, and the continued undermodelling of said craft will force an undue burden of learning upon those who's planes clearly cannot keep up with their skill.

[/sarcasm]

This is a bit OT (when talking about the slats): Personally I believe if the slats had posed a big problem without providing sufficient advantage they would have eliminated it from later models.

To my understanding some unexperienced pilots were afraid of going to points were slats would open. The reason I imagine is linked to what was said by a previous poster: It was very likely not smooth. So an unexperienced pilot might have been surprised by the rather sudden change in lift and may have reacted wrongly. Someone with experience would have learned to do the right moves at the moment the slats opened.

Another issue was perhaps that for symmetric opening one would have to avoid side slip and there also experience comes in, an experienced pilot likely being more automatic in maintaining symmetric flight than an unexperienced one.

I think I have read some pilot tales that said that the real manoeuvering for them started when the slats opened as the plane then could provide enough lift for tighter turning.

[Robo.]

Originally Posted by von Brühl

None of them say that when the slat deploys it makes it less manueverable like you suggest, nearly all of them state its the bang that makes it an unsettling experience.

I suggest you guys back off Osprey, clearly he's still in a state of aggravation from the Spit II's FM's being brought back to reality, further degradation of the wonderful properties of the Spitfire are just a bit to handle right now, especially since it seems that the devs backed the Spitnerf with a bit more oompf to the 109.

I can remember flying against Osprey on ATAG, he's an excellent pilot, any time he got shot down, was simply due to undermodelling the Spits and Hurri's, and the continued undermodelling of said craft will force an undue burden of learning upon those who's planes clearly cannot keep up with their skill.

[/sarcasm]

Yes you're right, he is an excellent pilot, not so much in Spitfire Mk.II but Mk.I fighters most of the time (just for the record ). What you say has nothing to do with anything. The truth is, even now, pre-patch, the Spitfire Mk.I is performing worse than it should be and it seems it will not be fixed, quite the opposite.

The issue has been commented and backed up with data - it seems that Spitfire is rolling too fast at given speed. The problem with fabric ailerons should be modelled in the sim (along with 100 octane fuel and correctly operating wingslats on the 109 etc etc ) if we want to pretend we're fighting in the Battle of Britain era.

What is the point of this argueing anyway?

[Osprey]

Originally Posted by von Brühl

None of them say that when the slat deploys it makes it less manueverable like you suggest, nearly all of them state its the bang that makes it an unsettling experience.

I suggest you guys back off Osprey, clearly he's still in a state of aggravation from the Spit II's FM's being brought back to reality, further degradation of the wonderful properties of the Spitfire are just a bit to handle right now, especially since it seems that the devs backed the Spitnerf with a bit more oompf to the 109.

I can remember flying against Osprey on ATAG, he's an excellent pilot, any time he got shot down, was simply due to undermodelling the Spits and Hurri's, and the continued undermodelling of said craft will force an undue burden of learning upon those who's planes clearly cannot keep up with their skill.

[/sarcasm]

Well I didn't mean to upset you about the slats von Bruhl. My comment was driven by Biff stating that the 109 couldn't be stalled. Had he said it about the "Spitnerf" (thanks for demonstrating your level of parity to us) then I'd have called him up on that too.

Is this a standard post you put up with a parameterised name though? Go check my stats on ATAG, I have no problem with that, you won't find many probably but you will find I that I don't get shot down very often. You're very unlikely to find a single Spitfire II sortie though, a few Spitfire I (2 stage) and Hurricane Rotol but that's it. My main gripe is putting a ton of lead into some 109 driver only for him to run away back home when he should be going in really. I'm not sure why you needed to attempt a character assassination when you could've just provided some examples though.

Do you fly as Von Bruhl? I'll have a look, I'll wager you can't live without mineshells.......