A newbies impression of the 109 and spit

[Catseye]

Originally Posted by gimpy117

It just makes me wonder how I held so much energy from that hard turn, where as the ME-109 seemed to bleed a crazy amount, and be a sitting duck for me to come around and fill him with lead. The Spit should turn better yes, But my question is...does it bleed energy as fast and is this historic?

Gimpy117,
Not having your realism settings set accordingly can initiate unrealistic performance as you describe.

Here is a pic of the realism settings FYI - check your Engine settings and Atomosphere and Handling.

S!

[Kurfürst]

The real 109E could do sustained turns in 18.92 secs at 1.3ata at SL, we have the 1.35ata version so probably it can be marginally better than that.. anyway, I did a quick test and got about that much, so I don't there's something wrong there.

I don't know how fast Hurris and Spits turn though. They should be better, but by how much? If they would do a sustained turn in 11-12 secs I'd say something is definietely stinking (that's a biplane only zone), but 15-16 secs would sound about right.

[BlackbusheFlyer]

Sorry Kurfurst but you are wrong about the spit elevators, they were sensitive yes but can in no way way be classed as ultra sensitive. I am a real world aerobatic pilot generally flying a Pitts special, and have flown many aerobatic types. The elevator on these aircraft IS sensitive, much much more so than the Spit. The Spitfire that went into service was and always has, been described as having well balanced controls (a twitch elevator would not accord this distinction!).

It is a well known fact that the British aircraft types were much more forgiving than the German equivalents, a factor in itself in the supremacy of the Spitfire over the ME109 during the Battle of Britain. You had 'green' pilots on both sides, but the Spitfire was markedly easier to fly for those pilots allowing inexperienced pilots to get more out of the machine than was typical of the Germans.

[Crumpp]

Sorry Kurfurst but you are wrong about the spit elevators, they were sensitive yes but can in no way way be classed as ultra sensitive. I am a real world aerobatic pilot generally flying a Pitts special, and have flown many aerobatic types. The elevator on these aircraft IS sensitive, much much more so than the Spit. The Spitfire that went into service was and always has, been described as having well balanced controls (a twitch elevator would not accord this distinction!).

It is a well known fact that the British aircraft types were much more forgiving than the German equivalents, a factor in itself in the supremacy of the Spitfire over the ME109 during the Battle of Britain. You had 'green' pilots on both sides, but the Spitfire was markedly easier to fly for those pilots allowing inexperienced pilots to get more out of the machine than was typical of the Germans.

Longitudinal Instability and the Pitts elevator are not comparible. There is a huge difference between the minimal stability exhibited by a Pitts and a dangerous instability exhibited by the Spitfire.

The Bf-109 is much more forgiving than any straight wing high aspect ratio design without LE slats. Think of the slats just like training wheels. An elliptical wing on the other hand exhibits very harsh stall characteristics because of its shape.

[bongodriver]

dangerous instability exhibited by the Spitfire.

OMG...you really do believe this crap!

An elliptical wing on the other hand exhibits very harsh stall characteristics because of its shape.

Yet the spitfire is well documented as having benign characteristics.......

[NZtyphoon]

Originally Posted by Crumpp

Longitudinal Instability and the Pitts elevator are not comparible. There is a huge difference between the minimal stability exhibited by a Pitts and a dangerous instability exhibited by the Spitfire.

Yeah Right, the Spitfire was so dangerous that pilots dreaded flying the machine and it was roundly condemned by the A&AEE, the RAE and by Supermarine test pilots, and has since been banned by the FAA and other aviation authorities worldwide.

No doubt Kurfurst will bring up the Spitfire V crashes described in Shacklady and Morgan...pp 160-161 (I think)

Or he'll post the attached paper and claim that this proves how dangerous and unstable the Spitfire was because so many of them broke up in flight.

So, to save all our time from his predictable arguments here's what Supermarine Chief Test pilot Jeffrey Quill had to say about the "dangerously unstable" Spitfire (Spitfire:A Test Pilot's Story. John Murray, 1983):

"In a high-performance fighter, lack of stability can be exceedingly dangerous in the course of manoeuvring at high speeds...Therefore, in aeroplanes such as the Spitfire, which were entirely manually controlled, any inherent instability was unacceptable and potentially dangerous....

There were other factors which affected the aerodynamics of the stability of the Spitfire. For example the aerodynamic characteristics of the elevator itself (as opposed to the fixed tailplane) also had a major influence on stability and at Supermarine we exploited this and increased the stability margins as we moved from one mark of Spitfire to another. (229-230)

In general configuration the Mk I and Mk II production aeroplanes were almost identical to the prototype and so there was no problem with their stability. (231-232)

The Mk III Spitfire did not go into production, but the success of the bobweight experiment in curing its instability...opened up the possibility of its use for later marks of Spitfire....which was just as well as we had to...respond to a nasty situation which developed in 1942.

The Mk V aircraft was...in full service with Fighter Command and,...a fair amount of additional operational equipment had gradually crept into the aircraft, most of it stowed within the fuselage. The aftmost acceptable position for the aircraft's centre of gravity had been fixed in the normal course of flight testing by the firm and by the A & AEE....Any rearward movement of the centre of gravity in service, for whatever reason, would begin to destabilise the aircraft. Therefore, for each sub-variant of the Mk V detailed instructions for the correct loading of the aircraft were issued to squadrons....However the importance of these loading instructions was not generally appreciated in squadrons and in the daily round of operational activity they tended to be disregarded." (pages 232-233 -Quill goes on to describe 65 Sqn's Spitfire Vbs which were found to be dangerously unstable)

There was thus a real chance that, as of that moment, in almost every squadron in the Command Spitfires were flying in a dangerous state of instability....Up to that time there had been a distressing and increasing incidence of total structural failure of Spitfires in the air, which was causing great concern in the MAP and especially at Supermarine. (pages234-235)

....our aerodynamicists at Hursley Park thought that an even more effective answer could be obtained by enlarging the horn balance of the standard elevator and this we did in stages. The effect was astonishing.

At last a way had been found to improve the basic stability of the aeroplane, thus giving more flexibility in centre of gravity movement, without our having resource to any enlargement of the fixed tail surfaces....The enlarged horn balance of the elevator produced a slightly unpleasant 'feel' of the aeroplane at low speeds...This effect was trivial by comparison with the gains in stability margins." (p 237)

Once the bobweights had been introduced and, in later marks, the modified mass balances on the elevators...it was statistically established that, as soon as the longitudinal stability of the Spitfire was thus brought under control, the problem of the unexplained breakings-up of aircraft in mid-air,...'softly and suddenly vanished away'. (page 238 )


Note the comments that stability margins increased over the course of Spitfire production; with the introduction of the Griffon engined Spitfires, and especially the five bladed propellers of the 65 series the size of the tail surfaces were increased to help cope with the bigger blade area and extended nose - there were some marginal instability problems, but not enough to make the aircraft dangerous. There were problems with the early Spitfire F. Mk 21's control characteristics, but these were ironed out with further developments in the elevator balance weights and configuration. The Mk Vs breaking up in flight were badly loaded with extra equipment in squadron service, with their cg pushed too far back, thus they were dangerously unstable, but this was not an inherent problem with the airframe.

No doubt Crumpp will try to claim that with his vast aviation experience he knows better than Jeffrey Quill and there'll be other smokescreens by another Spitfirephobe who has posted here but the fact is that All claims about the Spitfire being inherently dangerously unstable are quite false and not worth bothering with.

[NZtyphoon]

And here's what Alex Henshaw, Chief Test Pilot at Castle Bromwich, says about the flight characteristics: Spitfire demo flights:

"...The Spitfire would then continue with a series of loops and half-rolls to gain height over the airfield to between 4,000 and 5,000ft. Depending on the precise position of the aircraft in relation to the airfield, the usual procedure was to dive to 450-470 mph in front of the flight shed and then pull out and complete an upward roll to the left, one to the right and a half-roll left. This manoeuvre might be repeated or continued with a vertical dive with aileron turns...Considering how often this was demonstrated with all marks of Spitfires I am surprised that it should ever be suspected that wings might suffer structural failure in such a situation when excessive aileron loads were used in high-speed dives.

From the Mk I Spitfire up until the Mk 21 the Vne was set by the Supermarine technical department at 470 mph IAS at a height assumed to be between 5,000 and 10,000 feet....At no time did the Supermarine test pilots reduce the Vne from 470 mph to 450 mph....If ever any doubts existed within our own test pilots as to the structural risks of diving the Spitfire they were dispelled when reports were received from combat units to the effect that some of their pilots complained of excessive engine revs when diving under extreme conditions....The basic pitch setting of the de Havilland propeller was set to give 3,000 rpm at 9lb boost on take-off, and would remain in the constant speed range up to full power and not exceed 3,000 rpm up to its Vne of 470 mph...it was decided to investigate the problem to its limits.
A standard Mk V without calibrated instruments or modifications was taken up to 37,000 ft. A maximum speed run at full power with engine revs at 3,000 was carried out for 2 minutes before peeling off with a half-roll to dive down to near ground level. Up to the Vne of 470 mph the propeller constant speeded with engine revs at 3,000, and then as the speed increased the propeller came up against its basic pitch setting stop and engine revs climbed rapidly. The ASI indicated what might be assumed to be some degree of accuracy within the normal range, but as the speed progressed beyond the these limits the needle climbed so far into the region beyond the 450 mark that it was obvious that no further notice should be taken of it. We were not certain that the machine had in fact reached its terminal velocity point...it was decide to carry out another dive with greater concentration on the rev counter....This final dive proved two factors. With the single-stage blower Merlin, the Spitfire could not be dived faster, and at 3,700-3,800 rpm in those conditions the basic pitch setting should be readjusted." (Aeroplane Monthly September 1995, 55-56)

Yep the Spitfire was so dangerously unstable that Henshaw flew it like a maniac and crashed and died several times.

[NZtyphoon]

Originally Posted by BlackbusheFlyer

Sorry Kurfurst but you are wrong about the spit elevators, they were sensitive yes but can in no way way be classed as ultra sensitive. I am a real world aerobatic pilot generally flying a Pitts special, and have flown many aerobatic types. The elevator on these aircraft IS sensitive, much much more so than the Spit. The Spitfire that went into service was and always has, been described as having well balanced controls (a twitch elevator would not accord this distinction!).

Henshaw: "Compared with the Compar Swift, de Havilland T.K.4 or the Mew Gull the elevator controls on the Spitfire were quite heavy. To the young pilot trained on Tiger Moths or Magisters, however, the Spitfire elevators would indeed feel light, so that time and experience would be needed to get used to the feel." (AM September 1995 p. 55)

Quill on the prototype:
"The A&AEE pilots remarked also that the elevator was too light and too powerful and they recommended reducing the gear ratio between the elevator and the control column. I suspected at the time, and later with more experience and understanding of the problem I became quite convinced that they were wrong in blaming the elevator for being too light. This was much too simplistic a conclusion. The aeroplane was on the borderline of instability and making a heavier elevator, or even a smaller one, would have been no solution." cf his comments about further development increasing the stability margins. (Spitfire:ATPS p. 231)

Originally Posted by Crumpp

An elliptical wing on the other hand exhibits very harsh stall characteristics because of its shape.

As this phrase, as it stands here, is to my knowledge right, it does not apply to the spitfire. The spit had cranked wings with a reduced angle of attack at the outer parts of the wing (where the ailerons were). This meant that if, for a given speed, the angle of attack became too high on the inner section of the wing to generate lift it was still small enough on the outer sections. Hence while the wing stalled first on the inner section it stalled later on the outside section.

This was a security measure installed by supermarine because they were aware of the problem of the elliptical wing that you just mentioned.

When you read raf pilot accounts they repeatedly mention that they got buffeting shudder on the brick of a stall warning them about an imminent stall. This situation occured when the inner section stalled but not the outer section where the ailerons were, allowing the spit to be still controllable around the roll axis.

Of course cranking the wing also meant to deteriorate the aerodynamical properties of the elliptical wing so that it was less optimal aerodynamic wise. The induced drag was hence bigger than with an uncranked wing. As the advantage of the elliptical wing was later found to be minimal with respect to a trapezoid wing it was abandonned in aviation as the disadvantages in terms of production outweighted its minimal benefits. That's why I definitely think that the elliptical form in itself had nothing to do with the great performance. What supermarine however probably managed to pull off was to design a wing with a large surface which however created more drag but allowed for high lift which was still light weight and in particular very thin.

[Kurfürst]

[QUOTE=BlackbusheFlyer;419116]Sorry Kurfurst but you are wrong about the spit elevators, they were sensitive yes but can in no way way be classed as ultra sensitive. I am a real world aerobatic pilot generally flying a Pitts special, and have flown many aerobatic types. The elevator on these aircraft IS sensitive, much much more so than the Spit. The Spitfire that went into service was and always has, been described as having well balanced controls (a twitch elevator would not accord this distinction!).

I would have respectfully disagree with you assessment, particularly about control harmony. It was a weak part of Spitfire control, as the elevator indeed touchy, while. One Spitfire pilot described the phenomenon as 'touching the elevator with a light fingertip, while arm-wrestling the ailerons'. I would suggest you to study the Spitfire II pilot notes on control aspects, basically they all about instability in pitch and poor control harmony, here: http://forum.1cpublishing.eu/showpos...17&postcount=4

It particularly challenging thing to do when flying near the stall, NACA for example found that the stall boundary on the controls was very small, just 3/4 inch of stick movement having been found between the first sign of stall and actual stall. This was offset party of course by ample stall warnings and otherwise good stall characteristics, but it took an experienced pilot to fly the aircraft to its limits.

It is a well known fact that the British aircraft types were much more forgiving than the German equivalents, a factor in itself in the supremacy of the Spitfire over the ME109 during the Battle of Britain. You had 'green' pilots on both sides, but the Spitfire was markedly easier to fly for those pilots allowing inexperienced pilots to get more out of the machine than was typical of the Germans.

Again, an urban myth. British reports from the time readily admit the opposite. See:
http://kurfurst.org/Tactical_trials/...ls/Morgan.html

5. Fighting Qualities of the Me. 109. – 5.1. Dog-fights with Spitfire and Hurricane.

Mock fights were staged between the Me. 109 and a Spitfire, both flown by pilots of the R.A.E. In addition a number of fighter pilots, all of whom had recent experience of operational flying, visited the R.A.E. with their Spitfires and Hurricanes in order to practice combat with the Me.109 ; during these fights the Me.109 was flown by an R.A.E. pilot who had completed the handling tests described earlier in this report, and was thus thoroughly familiar with the aircraft and could be expected to get the best out of it. A brief account of the information provided by these fights has already been publishedlO. The following notes summarise the results obtained.

The arrangements were for the aircraft to take off singly and meet at about 6,000 ft. The Me.109 then went ahead and commenced to turn as tightly as possible to see if it would out-turn our own aircraft. After doing three or four tight turns in both directions the Me.109 was put into a dive, followed by a steep climb. The aircraft then changed position and repeated the above programme, after which the pilots engaged in a short general fight.

When doing tight turns with the Me.109 leading at speeds between 90 m.p.h. and 220 m.p.h. the Spitfires and Hurricanes had little difficult in keeping on the tail of the Me. 109. During these turns the amount of normal g recorded on the Me. 109 was between 2½ and 4 g. The aircraft stalled if the turn was tightened to give more than 4 g at speeds below about 200 m.p.h. The slots opened at about ½ g before the stall, and whilst opening caused the ailerons to snatch ; this upset the pilot's sighting immediately and caused him to lose ground. When the slots were fully open the aircraft could be turned quite steadily until very near the stall. If the stick was then pulled back a little more the aircraft suddenly shuddered, and either tended to come out of the turn or dropped its wing further, oscillating meanwhile in pitch and roll and rapidly losing height ; the aircraft immediately unstalled if the stick was eased forward. Even in a very tight turn the stall was quite gentle, with no tendency for the aircraft to suddenly flick over on to its back and spin. The Spitfires and Hurricanes could follow the Me.109 round during the stalled turns without themselves showing any signs of stalling.

The good control near the stall during these turns at full throttle contrasts with the results obtained from the ADM. 293 tests (section 4.42)) for when gliding the aircraft becomes unsteady at 10 m.p.h. above the stall. Slipstream thus appears to have a steadying influence on the behaviour of the Me.109 near the stall.

After these turns the Me.109 was put into a steep dive at full throttle with the airscrew pitch coarsened to keep the r.p.m. down. It was found that both the Hurricanes and the Spitfires could keep up with the Me.109 in the dive; the aircraft with constant speed airscrews could do this more readily than those with two-pitch airscrews. The ailerons and elevator of the Me.109 became so heavy in the dive that rapid manceuvring was impossible, while, as explained in section 4.22, banked turns could be done more readily to the right than to the left because of the absence of rudder bias.

The Me.109 was then pulled out of the dive and climbed at a very low airspeed at an unusually steep attitude. The aircraft was under perfect control during the climb, and could be turned with equal facility in either direction. Under these conditions it outclimbed our aircraft in most cases, since most of our pilots climbed at a higher airspeed and a flatter angle, keeping below the Me.109 and waiting for it to come out of the climb.

However, other pilots who chose to climb at very low airspeeds, mainly those with constant-speed airscrews, succeeded in keeping on the tail of the Me.109, although the Me.109 pilot thought they would have difficulty in keeping their sights on him steadily, as he was at a steeper attitude than their sights could " line ".

In most cases this steep climb at low airspeed was the only manceuvre whereby the Me.109 pilot could keep away from the Hurricane or Spitfire. During the general fighting which folIowed the set programme, one other feature of advantage to the Me.109 emerged. If a negative g is put on the aircraft for a short time, the engine does not cut as it is of the direct injection type; whereas on the Spitfire or Hurricane the engine immediately splutters and stops when negative g is applied, because the carburettor quickly ceases to deliver petrol under these conditions. Hence the Me. 109 pilot found that a useful manceuvre when being chased was to push the stick forward suddenly and do a semi-bunt, if our fighters followed him their engines cut giving the Me.109 a chance to get away ; this was particularly useful against the Hurricane, as its top level speed is less than that of the Me. 109 so that once the Me. 109 had escaped in this way it could avoid combat. The Spitfire, on the other hand, soon caught the Me.109 after this manceuvre.

When the Me.109 was following the Hurricane or Spitfire, it was found that our aircraft turned inside the Me.109 without difficulty when flown by determined pilots who were not afraid to pull their aircraft round hard in a tight turn. In a surprisingly large number of cases, however, the Me. 109 succeeded in keeping on the tail of the Spitfire or Hurricane during these turning tests, merely because our Pilots would not tighten up the turn suficiently from fear of stalling and spinning.

The oversensitiveness of the Spitfire I elevator and its tendency to flick over fall entering a spin was also noted by earlier British trials (April 1940) involving a Curtiss Hawk and by German trials in the summer of 1940, and by NACA in 1941 on Spit VA (metal ailerons):