Bf 109 F series

[silence]

Since the F series is often regarded as the pinnacle of 109 development, are there ways in which it could have been improved?

It seems the early Gs were basically up-engined Fs; could the 601E have been further developed?

How would it have fared against the late war allied fighters?

 

[davebender]

Heinkel and Focke Wulf fighter aircraft had bubbly canopy by late 1930s. IMO RLM should have insisted on an improved canopy for Me-109F. Even Erla style canopy would be a big improvement over historical Me-109F canopy.

Me-109F was designed for a level speed of about 400mph. Might be a good time to introduce Flettner tabs to improve high speed handling rather then waiting until Me-109G series.

 

[silence]

Is that the same as a servo tab?

And how about a bubble canopy like the Spit V and IX? I would think such a change would not interrupt production and be an easy in-field modification.

 

[davebender]

If Me-109 adopts a bubble canopy it would be like He-112B and/or Fw-190 as those aircraft were familiar to Messerschmitt by late 1930s.

 

[GregP]

Improvements to the Bf 109F:

1) Bubble canopy and a windscreen with much more narrow posts or no posts. No big deal, DO it.
2) Landing gear. Move the gear outward to widen the track. Easy but would mean a production interruption.
3) Add a rudder trim tab. No real issue and not much weight.
4) Increase mechanical advantage for the control stick. Easy and NO extra weight.
5) Reduce flap span by about 1 foot per side and add aileron span. Increase aileron travel and add tabs to reduce roll forces at high speed. The 109 already had a very low stall speed and short takeoff and landing distances. These steps wouldn't affect them much.
6) I'd leave the engine alone and try a wider-chord propeller. They worked well on the Fw 190's. Why not the 109's?
7) Add ore fuel. Put in another 20 gallons at least.
8) Finally, the biggest headache for many units all during the war ... add a damned electric starter! The scrambles would be MUCH quicker!
9) Once these are done, quit messing with it and get on with the successor while producing the new Bf 109F as rapidly as possible.
10) Steal as much 130-grade fuel as you can get and make that DB hum!

 

[beitou]

Where does the battery go for the electric starter, or do you mean a externaly powered starter? If external and each aircraft needs a power cart how much quicker would mass scrambles be? Is it worth carting round the honging big battery needed to start the beast?

 

[Tante Ju]

Improvements to the Bf 109F:

1) Bubble canopy and a windscreen with much more narrow posts or no posts. No big deal, DO it.
2) Landing gear. Move the gear outward to widen the track. Easy but would mean a production interruption.
3) Add a rudder trim tab. No real issue and not much weight.
4) Increase mechanical advantage for the control stick. Easy and NO extra weight.
5) Reduce flap span by about 1 foot per side and add aileron span. Increase aileron travel and add tabs to reduce roll forces at high speed. The 109 already had a very low stall speed and short takeoff and landing distances. These steps wouldn't affect them much.
6) I'd leave the engine alone and try a wider-chord propeller. They worked well on the Fw 190's. Why not the 109's?
7) Add ore fuel. Put in another 20 gallons at least.
8) Finally, the biggest headache for many units all during the war ... add a damned electric starter! The scrambles would be MUCH quicker!
9) Once these are done, quit messing with it and get on with the successor while producing the new Bf 109F as rapidly as possible.
10) Steal as much 130-grade fuel as you can get and make that DB hum!

1) It would require a serious redesign of the fuselage and may pose stability problems. An unnceccesary risk, maybe, as the rear view was fairly good with the armored glass headrest. Introduce those immidiately. Its not hard to cut a hole in a piece of steel and insert some glass into it... also heatable panels for freezing. Thats actually useful for winter/high altitude work.
2) Negative. The landing gear track isn't a problem, its geometry is. Introduce different angle tire mountings and long tailwheels sooner to solve problems, as on 109K.
3) Probably should be done, not many seems to be complaining, but hey, it costs next to nothing to add a knob. CC that to Herr Prof. Tank, too.
4) Probably useful too, though not vital. Decreasing physical loads on the pilot may be useful on one hand (getit?), but OTOH may also impose overstressing risks and good low speed control harmony. Maybe introduce non-linear control, if thats possible?
5) Partially disagree, tabs should be added - but the aileron control and travel was just fine already.
6) Already done. Propellers got wider in chord and tailored to the needs of every new engine, until they got really very noticeable by 1944 with late war those high altitude engines..
7) Probably unneccesary. The Fw 190 was fine, the Bf 109 had the same capabilities, so, what for? But it should be an easy fix, the fuel tank could be enlarged to the rear without any problem. Maybe ask the RLM if they want it. 70-10 kg of extra weight shouldnt be an issue. Or is it.
8) No space for that, sorry, we overlooked that in 1934. But you already signed a contract for 12 000 of them. Marketing departments addendum: doesn't seem to be that much of a problem in practice.
9) That would be the Me 262, the rest simply did not have a worthwhile improvement, or even were a step back in some areas, to be produced.
10) Why steal 130-grade fuel when you already have 150 grade fuel..?

+11 but could be point Zero as well: Fire the guy at the head of the Undercarriage Aerodynamic Cover Deperatment. He was doing nothing useful between 1936 - 1944. Already the 109E (or before) was supposed to have faired-over undercarriage and a retractable tailwheel. What went wrong until the 109K?! He cost the plane already some 20 mph in top speed (and range).

 

[l'Omnivore Sobriquet]

The Russians designers were ordered systematically to take the Me-109 G2 as their goal to better, in their famous long work to raffinate existing production types.
There has to be a reason !

 

[Civettone]

I agree. If these improvements were that easy, I am sure the guys at Mtt would have introduced them.

I think we should stay humble with our all-knowing wisdom toward the Bf 109. I do not think we know the full story behind each component and aspect of this aircraft. For instance, the reason why they did not introduce a bubble canopy was because it was more difficult to produce and because it would reduce max speed (like on the P-51D vs B/C)

Kris

 

[silence]

I just read *somewhere* that even when LW craft did have landing gear doors these doors were often removed in the field.

What would be the reason for this?

As another improvement, could the supercharger be enlarged?

 

[GregP]

Hi Tante Ju,

Let's just say that if we were running the Bf 109 program, we'd make wildly different decisions. We already know what happened, but I'm trying to make it BETTER, not let it flounder along as it did. I do NOT think a serious redesign was necessary to greatly improve the canopy. The radial-powered Bf 109 prototype had such a canopy and it wasn't a major issue. The improvements I suggested would have been lighter than the Bf 109G at least.

I don't think the Germans had plently of wonderful fuel widely available or the power in the DB engines would have been better per the displacement. The octane or performance numbers cited for their fuels weren't all that damned good. Don't tell me how the fuel was better than rated. I've seen the reports in great detail and have them in pdf format.

We had a group of former Luftwaffe Bf 109 pilots at Chino when the Russell Bf 109E was initially restored. To a man (13 of them) they were adamant that having the electric starter, as was fitted at Chino, would have made their lives MUCH easier. One even said if they had electric starters, they would have won the war! I, for one, believe them that it would at least have been of great benefit.

If you don't, that's OK. They all might be wrong. Me, too. I have cranked an intertia starter and didn't like it much when pressing a button was SO much easier, especially on a cold day. The weight penalty is almost meaningless compared with the gross weight and there's plenty of room in the fuselage. I can even climb into it myself behind the ccokpit, and have ... well ... into an Hispano Ha.1112 Buchon anyway.

So, what is YOUR list of suggested improvements to make the Bf 109F better and more competitive into the late war?

The main issues to me were canopy, landing gear, short range, and high control forces when going fast. Those are the primary faults I want to correct, without leaving out any single item.

 

[pattle]

I tend to think the F model was as good as they could make the Me109 at the time. I have read that at first there were concerns in the Luftwaffe that it was under armed, but that when it went into combat it's other qualities more than compensated for it's lack of guns. I think it was certainly the perfect plane for going up against P40's and Hurricanes in, and wasn't it the F model that gave the B24's such a rotten time over Ploesti?

 

[GregP]

The Bf 109F was a good figher. Minor changes would have made it MUCH better and maybe even competitive well into the future.

The G-series was a step backward, what with the weight increase. It needed more wing and more power to handle the weight, but never got it, and they left all the basic faults in the plane!

It had potential and was pretty good as it was, but some relatively minor changes would have made it much better ... I think.

 

[Aozora]

I'm wondering how JG 26 (or was it a rear echelon conversion unit?) managed to replace the MG 17s in the upper cowling of one of Galland's "special" F-2s with MG 131s without needing the large blisters used by the G-5 series on? Did this conversion see any combat? If it could have been done on the production line the MG 131s would have been a useful modification.

 

[Civettone]

Oh boy, this is going to be thread #673 about all the things which people (wrongly) believe were bad about the Bf 109. The same outdated stories about frozen controls, narrow landing gears, light armament, short range, ...



Kris

 

[Shortround6]

As another improvement, could the supercharger be enlarged?

Possibly, the supercharger did not stay the same through all models of the engine. The later DB 605s actually got a DB 603 supercharger, I believe but could be wrong, it may have been based on the 603 supercharger.

However a bigger supercharger not only weighs a bit more it takes more power to run, meaning you have a bit less power from sea level to near critical altitude on the same grade of fuel. The gain comes higher up.

Perhaps the slightly larger supercharger fitted to the 605 could have been used. An increase of just under 6mm in diameter but I don't know if their was a change in thickness. In any case the DB 605A had a Critical altitude 700meters or less higher than a 601E and a good part of that came from the higher rpm. 200 rpm on the crankshaft is worth just over 2000 rpm on supercharger impeller.

Picking supercharger performance is always a trade-off. High altitude performance is always bought with a low altitude penalty of some sort.

 

[GregP]

Hi Civettone,

You won't get that from me. I thought the intent of the thread was to suggest improvements for the Bf 109F, not to trash it.

The controls did NOT freeze. Above 330 mph they were objectionably heavy and there was a remedy that was never implemented. Stop living with the weaknesses and FIX it. That way, the Bf 109 would not be so unmaneuverable at higher speeds.

The landing gear WAS narrow and the geometry was wrong. The intent is to fix it. By all means try the geometry fix first. If that did the trick, go with it. If it was still dicey, MOVE THE DAMNED GEAR OUTWARD AND FIX IT. Doesn't mean the 109F was bad, it wasn't. It means there was room for improvement.

I never mentioned the armament but could. It was light but effective. To avoid a heavy "solution" simply supply more ammunition for the existing armament and FIX IT.

The range WAS too short. If anyone doesn't see that as a major fault, then you would have lost just as many Bf 109's to fuel exhaustion as happened in real life. It was a crime that was preventable. FIX IT.

The Bf 109F was the pinnacle of the 109's in the eyes of many of its former pilots and was a very good fighter. My suggestions do NOT insinuate it wasn't … they are suggestions to make it better than it was in real life since that was the subject of this thread.

If you think it was as good as it could be, then you simply have no suggestions for improvement to the Bf 109F. I do have suggestions and all would have been welcomed by the WWII Luftwaffe Bf 109 pilots.

No suggestion that the Bf 109 was a poor representative of German fighters, it wasn't. It was VERY good but, like many fighers, could have been better with a few relatively minor changes that were desired by the pilots ... who never seem to get listened to by the people in command.

 

[Shortround6]

Oh boy, this is going to be thread #673 about all the things which people (wrongly) believe were bad about the Bf 109. The same outdated stories about frozen controls, narrow landing gears, light armament, short range, ...

Except they are mostly true

The controls were not as "frozen" as many people like to believe but there were problems, and the 109 wasn't the only plane to suffer this way.
Narrow landing gear, yes, but so did a few other planes (not just the Spitfire, the Wildcat had it's share of landing gear/taxiing problems).
Light armament? if we are talking about the majority of the "F" model then it WAS light. Heavy compared to a Japanese KI-43 or Italian planes with two 12.7mm guns but compared to the vast majority of western allied planes in 1941/early 1942?
Please do not point to the poorly armed Russian aircraft as justification. The had both engine power and quite possibly CG problems in trying to increase armament. They certainly trialed enough heavier combinations to show they were not happy with the armament they were using.

Range?
You can fly a P-47 (with the small fuel tank) over 800 miles on internal fuel, you just can't do it at an altitude and speed that will allow it to survive in enemy airspace. What counts is the 'practical' range/radius a plane can fly at speeds/altitudes that allow it to be effective. The P-47s 835 mile "book" range turned into a 125 mile radius when figured for "standard" mission conditions.

The 109 was short ranged. So were a number of other fighters (P-39) What really hurt is there wasn't anything to take it's place, the Fw 190 wasn't enough different to say so and the Bf 110 was??? The Americans had the P-38 in the early years (1943) to make up/cover the P-47s lack of range. BUT the P-47 had the size/bulk to enlarge the internal fuel to 370 gallons and the extra 65 gallons was worth another 100 miles radius even without drop tanks.

Sticking with the "F" it was a major improvement over the "E". There are few, if any, negatives about the "F" compared to the "E" except possibly the armament. The real problems with the 109 come with the "G" and even then it is the later ones.

Lots of WW II fighters could have been improved with very minor changes (in some cases just rearranging some of the cockpit controls).

 

[silence]

I'm wondering how JG 26 (or was it a rear echelon conversion unit?) managed to replace the MG 17s in the upper cowling of one of Galland's "special" F-2s with MG 131s without needing the large blisters used by the G-5 series on? Did this conversion see any combat? If it could have been done on the production line the MG 131s would have been a useful modification.

Good point. How would the small bump 13mm cowl - or adding the outer wing 20mm - affect performance? Could MG 151/20s or 151/15s have been fit in lieu of MG FFs?

 

[Tante Ju]

Good point. How would the small bump 13mm cowl - or adding the outer wing 20mm - affect performance?

The 13mm bumps decreased top speed by 9 kph at SL, ironically the wing 20mm gondolas - only by 8 kph. The gondolas (with ammo) also added some 215 kg weight (the HMGs only + 40 kg), which meant about -2 m/sec decrease in climb rate and ca. + 2 sec slower turns.

Kurfürst - Leistungzusammenstellung Me 109 G.

The 13mm bulges were far from ideal, the later revised cowling decreased the loss to only 3 km/h. Its amusing why they were designed so badly. The question why the solution on Gallands personal ride was not adopted is interesting, but it might have not been so ideal for feeding/aerodynamics perhaps. The reason for the cowl bulges was that the guns were not fed from outwards on the serial planes, so perhaps Gallands mod was not feeding reliably enough.

Here is a picture of Gallands modded 109F(-2/U). Note the teardrop shaped bulges for the HMG.

Another of Galland 109F he has modded with wing MG FFs and the "Galland Panzer", named after him, which placed a transparent armor glass into the standard and bulky armored headrest.

Could MG 151/20s or 151/15s have been fit in lieu of MG FFs?

There are drawings of that being proposed for 109K wings, so at least physically they would fit (with 100 rpg). They could also fit the bulkier MK 108, with 45 rpg.