Bf109 success, balanced fighter, or superior fighter?

[Soren]

Soren - I don't claim to know why the German engineers didn't provide boosted controls for the 109 but I am reminded that Lockheed did exactly that for the elevators on the P-38 to 'solve' compressibility dive recovery issue'.

Boosted elevators worked in the sense that control forces were manageably 'light' - but the airframe somehow lost it's tail in the process. I suspect without proof that neither the 109 aft structure or perhaps the wing structure were designed for high speed asymmetric load conditions that boosted controls would exacerbate.

I do know that Mustang designers provided REVERSE boost to rudder to INCREASE rudder pedal force requirements in dive and slow rolls - as the Mustang controls were too light, relatively speaking for those manuevers - and resulted in overstressing the airframe in certain assymetric load conditions.

The wings could take it, but the aft fuselage I aint sure about. So you could be right.

 

[Timppa]

the "1.8X" factor was a figure you regurgitated with no knowledge of the practices of German engineers, or, it is obvious that airframe structures engineering is not your core knowledge base but you wished to sound knowlegable??

I would have like to continued on this interesting topic, but , OK, whatever..

 

[drgondog]

I would have like to continued on this interesting topic, but , OK, whatever..

I could take it from the above comment that a.) you were interested as a non practitioner trying to learn something, or b.) a practioner debating specific points based on your own experience and different POV, or c.) just being contentious and now retiring from the debate because you are over your head and know it?

While you may not have intended to be obnoxious in your comments you managed (successfully) to irritate the hell out of me with what seemed to be condescending and ill informed snide remarks about a subject you didn't appear to have any knowledge.

If the first description fits you need to go to 'charm school' and ponder more on polite communication. I have to occasionally take a refresher course myself so I apoloogise if I mis interpreted your remarks..

Regards,

Bill

 

[davebender]

Was the Me-209 simply too late to matter? It makes little sense to mass produce a new piston engine fighter aircraft at the same time the Me-262 is entering mass production.

 

[vanir]

I'm making a habit of starting posts with "from what I've read" in a similar way on philosophy forums I start them with "in my opinion"

From what I've read the Me-209/309 development was found to provide no significant performance gains over the current Me-109G in production (I assume based on the presumption the DB-605D would soon be available for it). It was a terrific upset for the fighter industry for almost no immediate benefit. Also the DB-603 engine had not entered production yet (for the 309) and so maximum performance versions had not even been bench tested (part reason for the RLM backing of the Jumo engine for 190D/Ta152 initial projects, if Tank had his way the 603 would've been available and the 190D would've been a Ta152C from the start).

Essentially the Me-209 was passed over for the Fw190D.

The development of jet fighters versus piston engine fighter production was a separate issue. Jet engines were relatively untested and had not been service tested in combat conditions, as it turns out their serviceability rates and combat damage sustainability are extremely low. They were a sign of the times, but not a replacement as yet.

 

[Shortround6]

While the 109 started it's career as a day fighter ( in 1936-38 there wasn't much else) the availabilty of engines did hurt it's further development. THe Jumo 210 may have been a decent enough engine for it's time but the decision to go for max performance with this engine did rather affected the the entire history of the fighter. Imagaine a Hurricane or Spitfire designed around a Kestrel instead of the Merlin.
While in the Spain the 109 did a rather good job it was competing against (or with) other aircraft with engines in the 600-700hp neighborhood. Most fighters had 2-4 rifle caliber MGs and had similar range.
That the 109 could take the DB 601 engine was fortunate and good planning. With it the 109s utility grew, Heavier armament, better performance (even if range didn't change much) and the ability to be used as a fighter bomber with a 250kg load. The Plane can now do fighter bomber missions and with the wing mounted 20mm cannon it makes a good (for the time) bomber destroyer. It has become a multi-mission aircraft. Drop tank on bomb shackles doesn't hurt either.
However it is at this point that the 109 design begins to peak. The "F" model with aerodynamic refinement and higher power engines does show much improved flight performance. However armament is considered by some to take a step backward. Range improves only by the lower drag of the new airframe and bomb load doesn"t change. It is now a better fighter vrs fighter aircraft although against bombers it might be less effective. Fighter bomber and long range fighter haven't changed much. The 20mm mg 151 does help later "F"s.
The "G" models start a reversal of the 109s utility. A larger engine means more flight performance but it also means shorter range on the same sized fuel tank. As heavier armament is added ( and one 20mm and 2 7.9mm mgs are no long adequate) the weight goes up and the performance from the larger engine goes down. Bomb load stays the same.
As later "G" models show up the limitations of the 109 become apparent. It is no longer a general purpose fighter. It has become specialized. It's armament is too light for bomber interception. One 20mm and two 13mm MGs just won't cut it. changing to the 30mm Mk 108 helps for anti-bomber missions but the low velocity of the 30mm doesn't do much for deflection shooting against fighters. Special "anti-bomber" versions are fielded with under wing guns. While more effective against bombers they mark the end of the 109 as a general purpose fighter. TWO squadrons of 109s are needed, one squadron without underwing guns to engage the escort fighters while the more heaviely laden "gun ships" attack the bombers. Bomb load hasn't changed although I doubt the "gun ships" carried bombs very often.
Even later models of the DB 605 can't help the "utiltiy" much. While they do improve straight line speed, climb and perhaps sustained turn (as opposed to a turn that bleeds off speed) they can't do anything for the higher wing loading and detoriating handling.
Many allied fighter planes on the other hand could (even if it wasn't smart) change roles from day to day. While many of the "modifications" to the 109 were supposed to be "field kits" I rather doubt that a squadron did bomber intercepts on Monday, bombing missions on Wednesday, and performed the anti-fighter role on Friday. While the 109 'type' fighter could perform all of these roles the individual fighters could not. The small size of the 109 (inherited from the jumo 210 models) ment that the 109 could only succeed in one role at a time. The small size also ment that the 109 never advanced in the ground attack/fighter bomber role either. While the 1100hp versions could carry a 250kg bomb the 2000hp versions couldn't carry anything bigger. And give the 605's appetite for fuel the likeily hood of getting very far with bomb wasn't very good.
The 109 by wars end had devolved back to a day fighter or short ranged interceptor and a rather tricky one for a low time pilot to fly at that.

 

[davebender]

That the 109 could take the DB 601 engine was fortunate and good planning

I am under the impression the Me-109 was designed for the DB600/601/605 engine. However early model aircraft had to make do with whatever engines were available while the new DB engine factory was being constructed at Genshagen.

 

[Shortround6]

Considering that metal was cut for the first prototype 109 in late 1934 and that a DB 600 powered 109 didn't fly until the spring/summer of 1937 I think that "fortunate and good planning" holds up. Good planing in that the airframe was designed to take the DB engine without modification and fortunate that the DB engine did "eventually" turn out to be a suitable fighter engine. Something that was by no means a sure bet in 1934

If the Jumo 210 had been developed in line with the 211 it might have been good for 900-1000hp. So if the DB 600/601 had been a failure there was least some hope of back up. I don't think that there was such a plan, just pointing out that designing a plane to take alternative engines might be a good idea. Considering that without the Jumo 210 the 109s service in Spain might have been both little and late.

 

[davebender]

1930.
RLM request to develop an 800 hp liquid cooled V12. This eventually produces the DB600.

1933.
RLM request for a single engine fighter.
RLM request for a heavy fighter.
RLM request for a tactical bomber.
RLM request for a medium bomber.

1934.
DB600 engine prototype.
Some other firms like BMW had engines in this competition. If the DB600 doesn't work then one of the other engines will win.

1934.
RLM specification to develop the Jumo 211 aircraft engine.
I assume this was insurance in case the 1930 specification which produced the DB600 is a failure.

1935.
RLM request for a heavy bomber.

1936.
DB600 wins the engine competition. Since DB has no suitable production facilities (destroyed by Versallies Treaty in 1919) there was a delay of about a year while building a new factory at Genshagen.

1936.
Me-109 approved for mass production.
Me-110 approved for mass production.
He-111 approved for mass production.
Do-17 approved for mass production.
Ju-87 approved for mass production.

 

[DerAdlerIstGelandet]

I am under the impression the Me-109 was designed for the DB600/601/605 engine. However early model aircraft had to make do with whatever engines were available while the new DB engine factory was being constructed at Genshagen.

The original requirement from the RLM stated that the aircraft was to be powered by the Jumo 210. This of course was before the 109 was actually designed. It was called the Rüstungsflugzeug IV and was laid out in 1933.

The original Bf 109V-1 was powered by a Rolls-Royce Kestrel VI due to the lack of the Jumo engines at the time. The V-2 was then powered by the Jumo 210. It was not until the Bf 109V-10 that the DB 600 was introduced. In fact the Bf 109A and B and C were all powered by the Jumo 210. The Bf 109D was powered by the DB 600 was powered by both the Jumo 210 and the DB 600. The Bf 109E was powered by the DB 601.

 

[Sweb]

It was a good gun platform and could be used successfully by experienced pilots. It's weaknesses were it's range and armament which translated to short combat durations and air-to-air competitiveness with heavier armed and longer ranging opposition. When it had to break off combat due to fuel/ammo shortage the opposition could still linger and chase it down. Better pilot visibility could have been incorporated earlier in its design evolution. These shortcomings were never resolved. The Galland hood still left a blind spot in the 6. It should have gone the way of the Hurricane and been replaced with another more suitable design like the evolved FW-190D variant and later.

I always saw the BF-109-Series as having lost air superiority with the introduction of the long ranging and heavily armed Allied fighters. They soldiered on but there was no way the airframe could compete as experienced pilot attrition gave the Axis green horns that couldn't successfully use the BF-109 to its design limitations against superior Allied designs. The same holds true for the PTO in regard to losses of experienced pilots flying older designs.

 

[davebender]

The Me-109 was at it's best during 1939 to 1940 when almost all the Luftwaffe pilots were rookies.

 

[DerAdlerIstGelandet]

The Me-109 was at it's best during 1939 to 1940 when almost all the Luftwaffe pilots were rookies.

I would not go as far as saying that. Remember that a lot of pilots had experience in the Spanish Civil War.

 

[Shortround6]

A 109E even with 4 MGs was still an 1100hp airplane with retracting landing gear compared to what the Poles could put in the air. Against the French the MS.406 was rather low powered (860HP?) and once the 60 rounds for the cannon ran out down to 2 RCMGs. THe D.520 was a 920-960HP aircraft. The Curtiss Hawk was actually one of the better fighters the French had in any real numbers and the Germasn did lose several hundred fighters against the French didn't they?
This provided the LW with quite a number of pilots who had seen some combat before the BoB.

The Hurricane's airframe was too dated to make full use of the 1400-1600HP Merlins that were lated fitted.
The Spitfire could make better use of the power.
While more powerful engines could and were fitted to the 109 it was too small to have it's armament increased in proportion, and too small to hold larger fuel tanks.
Didn't the MK VIII Spitfire (used in other theaters than europe) have fuel tanks in the wing leading edges and late model MK IXs have rear fueslage tanks? This might not have given a large increase in range over the earlier SPitifres but may have kept the range from falling becasue of the lhigher powered, thirstier engines.

 

[syscom3]

Don't know if its true, but didn't Galland himself want Germany to drop production of the -109 in favor of the -190?

 

[Kurfürst]

Imagaine a Hurricane or Spitfire designed around a Kestrel instead of the Merlin.

Actually, they were, they just evolved on paper before the Kestrel versions were put into production.

Even later models of the DB 605 can't help the "utiltiy" much. While they do improve straight line speed, climb and perhaps sustained turn (as opposed to a turn that bleeds off speed) they can't do anything for the higher wing loading and detoriating handling.

I guess you can say that to all late war aircraft - they were all greatly increased in weight, and thus wing loading, since wing area remained the same. Stall speed and turning circle as a result increases with wing loading, but as noted this is pretty much true for all major fighter designs of WW2.

Many allied fighter planes on the other hand could (even if it wasn't smart) change roles from day to day. While many of the "modifications" to the 109 were supposed to be "field kits" I rather doubt that a squadron did bomber intercepts on Monday, bombing missions on Wednesday, and performed the anti-fighter role on Friday. While the 109 'type' fighter could perform all of these roles the individual fighters could not.

Nope, you are wrong in this. One of the most important improvements of the G model was its versatality, and standardized kits, and the wiring etc. provided in each airframe. The basic field kits - bombs, droptanks, 21 cm rockets, gunpods - could be applied to any generic fighter of the 109G/K genre*. Say a G-10 could - and towards the end of the war, it sometimes did - fight with a droptank one day, gunpods the other day and bomb troops the third day. Technically, nothing was preventing it, though it probably not effective because the pilots did not have experience in all those roles, esp. given late war training.

* The only exceptions are some very specialized, limited production subtypes, such as the G-1/R2 lightweight high alt. fighter which IIRC couldn't carry gunpods because the GM-1 system was in its place in the wings.

The small size also ment that the 109 never advanced in the ground attack/fighter bomber role either. While the 1100hp versions could carry a 250kg bomb the 2000hp versions couldn't carry anything bigger. And give the 605's appetite for fuel the likeily hood of getting very far with bomb wasn't very good.

I agree it wasn't particularly exceptional in that role, but it could fulfill it reasonably. It was about avarage on those roles, worser than some, better than others.

Actually, the early 601 versions (ie. E model) could carry an 500 kg bomb, but it wasn't used because there was very little clearance under the fuselage. 1000 HP and airframe strenght was quite sufficient already. With the long tailwheel introduced, the 109K could take the larger sized 500 kg bomb (and most likely those late Gs with a long tailwheel, even if officially it was not listed).

There were G versions (ie. G-1/R1) that could cope with an 1000 kg load (one 500 kg under the fuselage, and two droptanks weighting around 250 kg each), and I guess there wouldn't be much in it hang an 1000 kg bombload if it would be really neccessary, but the FW 190 was already filling in the Jabo role nicely.

Mentioning the 605s apetite strikes me as an oddity, since one of its fortes were its very good fuel economy relative to others, and the good effiency of the powerplant as a whole.

The 109 by wars end had devolved back to a day fighter or short ranged interceptor and a rather tricky one for a low time pilot to fly at that.

Actually as far as the 109 range issue goes, the early Jumo ones had reasonable range, the Emil, for some reason, despite the increased fuel capacity was much shorter ranged, but the later ones were again a great improvement in that field. All 109F/G/Ks had very similiar range, ca 8-900-1000 km on internal, and 1600-1700 km with a droptank. The 109K could be the longest ranged (not counting some special long range recce variants, ie. G-4/R3, G-6/R3), since the rear 'booster' MW tank could also double as a aux. fuel tank of 115 liters capacity. Tricky flying, I don't think there was especially difficulty flying the late ones, not anymore than the challanges faced by all pilots with those 1700-2000 HP monster engines.

 

[Civettone]

Don't know if its true, but didn't Galland himself want Germany to drop production of the -109 in favor of the -190?

Galland was a soldier and had a limited view. The main advantage the Bf 109 had over the Fw 190 was that it was much easier/faster to produce* while it performed as good as the Fw 190. Sure, the Fw 190 had advantages, and Galland was one of those who preferred the FW but then again, there were several pilots who preferred the Bf.

* You'll often read that the Bf 109 could be produced in 5,000 manhours but in fact at the end of the war they needed only half of that. I don't know the manhours for the Fw 190 but it's probably safe to say you could build at least 1,5 Bf 109 for every Fw 190. And that is what really matters at war. We aircraft enthusiasts can all go and on about a couple of mph more or less or roll rate seconds and stuff like that. But in the end, it's numbers and pilots. Americans realized that and that's why they won the war. (And because they had the Andrew Sisters...)

Kris

 

[Waynos]

Actually, they were, they just evolved on paper before the Kestrel versions were put into production.

No they were not. The Spitfire and Hurricane were both designed around the Merlin, their predecessors, the Type 224/ early type 300 and Fury Monoplane were designed around the Goshawk. The Kestrel was never considered for either type.

I guess you can say that to all late war aircraft - they were all greatly increased in weight, and thus wing loading, since wing area remained the same. Stall speed and turning circle as a result increases with wing loading, but as noted this is pretty much true for all major fighter designs of WW2.

From sources I have read the Bf 109 always had a higher wing loading relative to its rivals and this meant that it suffered a greater degradation in its handling as a consequence of the ever increasingh power installed. Also, measures were taken on later marks of Spitfire to address the deterioration in handling (such as the new wing on the mk 20 series. I am unaware if any steps were taken to address this with the 109?

 

[Shortround6]

"I guess you can say that to all late war aircraft - they were all greatly increased in weight, and thus wing loading, since wing area remained the same. Stall speed and turning circle as a result increases with wing loading, but as noted this is pretty much true for all major fighter designs of WW2. "

True as far as it goes but it is the small size of the 109 that makes the problem worse for the 109. comparing it to a Spitfire for example the Spitfire can carry a 90imp gal drop tank for the same increase in wing loading as a 109 carring a a 66imp gal tank. A plane with a 300sq. ft. wing could carry 115imp gal of drop tanks.
I am using drop tanks as an illustration. Thinking of it another way, adding a fixed amount of weight say, 250 kilos, increses the wing loading of the smaller plane by a larger percentage and thus affects it's handling more.

"Nope, you are wrong in this. One of the most important improvements of the G model was its versatality...."

Some of those "field kits" were factory installed and I rather doubt that ALL 109s were fitted/wired to carry ALL the kits. And I think you missed the point. The point was that the Allied aircraft didn't have to have a number of fitters/mechanics altering the planes from one configuration to the other. Hang bombs or fuel tanks yes but detach and attach gun pods? Wouldn't they have test fire the under wing gun pods to check alianment?

By the way, was the 109G2/R1 ever used in service? and no it wasn't the longer tail wheel on late Gs and the K. It was (in addition to other modifications) a seprate oleo leg attached to the first rear fuselage frame that seperated from the aircraft by explosive bolts and parachuted back to ground for re-use.

"Mentioning the 605s apetite strikes me as an oddity, since one of its fortes were its very good fuel economy relative to others, and the good effiency of the powerplant as a whole."

It may have had good fuel economy and effiencency compared to other 1500hp engines but compared to a 1100-1200hp engine I betting it used more fuel per minute. Considering that the fuel tank wasn't changed in size from the 1100HP version that doesn't sound like more range. While the higher power settings don't have to be used all the time taking off and climbing with a 250kg bomb isn't usually done at cruise power settings. Bombs also decrease range in two ways. one is the drag of the bomb itself. The other is that for a given speed and weight there is ONLY ONE angle of attack for the wing that will give level flight. flying at the same speed with an increased load means a higher angle of attack is needed which means more drag which means a higher throttle setting. Or a lower speed (range) for the same throttle setting.

"All 109F/G/Ks had very similiar range, ca 8-900-1000 km on internal, and 1600-1700 km with a droptank."

OH, Really? at what speeds and altitudes? and going from 800 to 1000 is a 25% improvemnent all on it's own. While you might be able to fly a 109 1000km on internal fuel are you even flying at 330kph?

at least one account of the 109 describe it's handling as "malicious" and most claim that it was dangerous to low time pilots. Again it is a matter of size and balance. stuffing a 1700-2000hp engine in a 7000lb airplane is going to give you a more difficult plane to control than 1700-2000hp in a 9-10,000lb plane in general. Rearward shifts in gravity don't help either and few allied planes had rather severe restictions on manuvers and allowed aiespped when rear fuel tanks were full.

 

[Kurfürst]

No they were not. The Spitfire and Hurricane were both designed around the Merlin, their predecessors, the Type 224/ early type 300 and Fury Monoplane were designed around the Goshawk. The Kestrel was never considered for either type.

You are right about that they were designed for the Goshawk, not the Kestrel. Still, their design history is analouge to the 109s in that originally a smaller engine was planned, and then when a larger, more powerful engine was available, they re-designed them to use the newer, bigger engine.

I do not see much difference, really. Besides, an aircraft not like a human, that once it is born, it has a rather fixed set of attributes that you cannot really changed. Once you re-design it, it will simply become a different aircraft; it can be adopted, the centre of gravity can be altered, the structure strenghtened if needed etc. etc.

From sources I have read the Bf 109 always had a higher wing loading relative to its rivals and this meant that it suffered a greater degradation in its handling as a consequence of the ever increasingh power installed.

It depends to what do you compare it to. The Spitfire, or Zero for example, had relatively low wing loading, but Russian and US Army types tended to have similiarly high wing loading as the 109. The P-47 for example, had a much higher one, but IIRC from the handling POV it was quite okay, despite the fact that it had much higher wing loading than *any* 109 version..

The second thing to be remembered that the 109 did not take so much weight increase as some others during the war. The early E version weighted 2610 kg, the last versions, 3362 kg (+28%). It was not particularly outstanding increase, Spitfires, for example, went from something like 2746 kg to 3859 kg (+40,5%) and over 4 tons (4176 kg, 52%) if you include the Mk 21) between the start and end of the war.

Also, measures were taken on later marks of Spitfire to address the deterioration in handling (such as the new wing on the mk 20 series. I am unaware if any steps were taken to address this with the 109?

Hmm, what the basically complete re-design of the wings in 39/40 (109F)? Revised slats, flaps, new Frise ailerons, revised wing planform.. it was quitea substantial redesign, and they seem to have fixed the existing handling problems (which had little to do with the wing loading anyway, but things like aileron snatching etc). The slats design was also changed on the G version, and there were of course small fixes like larger tail units to compensate for the increase in engine power and speed. There were also steps taken to improve its ground handling, the only real vice in the handling of the aircraft, for as far as I have read, in the air it was an extremely fogiving one, being nearly impossible to entered into a flat spin, for example. I have read Beauvais on this, and he literally struggled to do it by employing absolutely crazy manouvers.. it was not easy to do, even wantonly.

AFAIK the redesign on the Mk 20 was address other issues (amongst others, the poor rigidity of the oringal wing under load), but they ran into some serious (directional) handling problems. The new winged one from what I have seen had incomparably better roll rate at high speed, but at low speed it was inferior. I would rather say the new wing on the Spit was to be tailored for different requirements.