# Bf109 - why no bubble canopy ?



## vinnye (Aug 19, 2013)

Given the length of time that the Bf109 was in service and development, why did they not go to a bubble type canopy and lower rear fuselage?
I have seen interviews where pilots often said that the visibility out of that cockpit was not good. If this is correct, why did the LW not make changes to rectify this?


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## norab (Aug 19, 2013)

I don't think the Germans had the technology to mold a true bubble canopy until too late in the war to interrupt production


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## stona (Aug 19, 2013)

norab said:


> I don't think the Germans had the technology to mold a true bubble canopy until too late in the war to interrupt production



Fw 190 ?

Steve


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## Kryten (Aug 19, 2013)

FW190 canopy was made in two halves I believe, with a joint along the top running front to back?


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## stona (Aug 19, 2013)

Kryten said:


> FW190 canopy was made in two halves I believe, with a joint along the top running front to back?



The early flat sided versions, which I suppose makes them clear vision (no frames) rather than bubbles, had a hinge running back from the front edge about 1/3 the length. This was to allow the canopy to flex as it was opened and closed. It needed some movement as the width at the front changed from 66cm to about 53 cm.
Later "blown" canopies were made in two halves for the same reason. These were actually easier to produce and improved pilot vision further.
Cheers
Steve


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## bobbysocks (Aug 19, 2013)

i dont know how much you want to ( or even can ) lower the turtledeck..or area behind the canopy. the 109 has one of the slimmest fuses of ww2 ac. i fear a malcolm hood canopy would do the same as the bumps on the later 6 series. give you more drag as a trade off for a little better vision.


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## tyrodtom (Aug 19, 2013)

I'm sure i'll be corrected if i'm wrong. But I can remember reading the Malcolm hood actually increased the airspeed slightly on the Mustang Is when the RAF installed them.

The airstream is already being moved outward by the windscreen returning it to parallel with the gentle curves of the Malcolm hood might cause less turbulence than the sudden change the airflow has to undergo when going from the windscreen to the flat side canopy, on the stock P-51B canopy.
British pilots claimed the Malcolm hood gave them better overall vision than the bubble canopy on the P-51D.


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## Crimea_River (Aug 19, 2013)

Not a true bubble but the Me 309 was planning on a low back fuselage with a framed 360 degree view canopy.


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## Airframes (Aug 19, 2013)

The later, Czech-built Avia '109' had what was probably the nearest to a 'bubble' canopy. To achieve a full 'bubble', for example similar to a Typhoon or P-51D, I think would require some major re-design of the fuselage, which was built in two halves. Lowering the rear fuselage of the Spitfire and Mustang was 'relatively' simple, in engineering terms, compared to the construction of the '109.


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## The Basket (Aug 19, 2013)

The radial engined 109 had a better canopy. But the fuselage looks a lot fatter and wider.

Might be a trick of the eye to fit the radial.


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## bobbysocks (Aug 19, 2013)

i think to get the full effect of a bubble canopy you would have to raise the height of the pilots seat in a standard 109.


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## davebender (Aug 19, 2013)

Heinkel He 112 - Wikipedia, the free encyclopedia


> He 112B had a completely redesigned and cut-down rear fuselage, a new vertical stabilizer and rudder, and a completely enclosed cockpit with a bubble-style canopy. The canopy was somewhat more complex than later bubble designs; instead of having two pieces with the majority sliding to the rear, the He 112B's canopy was in three pieces and the middle slid back and over a fixed rear section. Even with the additional framing, the He 112 still had excellent visibility for its day. Armament was also standardized on the B model with two 7.92 mm (.312 in) MG 17 machine guns in the sides of the cowling with 500 rpg, and two 20 mm MG FF cannons in the wings with 60 rpg. For aiming, the cockpit included the then-modern Revi 3B reflector gunsight.
> 
> The first B series airframe to be completed was V7 in October 1936









Semantics of "true" vs "untrue" bubble canopy don't matter. Germany obviously had ability to make a canopy with excellent all around vision during 1936.


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## Airframes (Aug 19, 2013)

The German clock industry were also moulding 'Perspex' domes in the 1930s, so presumably the technology and knowledge were there.


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## GregP (Aug 19, 2013)

How about the all-round vision canopy on this Bf 109 with a radial engine?






If they could do it for a prototype like this then why couldn't they do something similar for the production line? And the windscreen has been changed for the better, too. So here's a "fix" that was tried but never incorporated. Unbelievable.

Not a true "bubble" but better than the stock Bf 109 canopy.

Sorry to post this again so soon after last time, but it seems appropriate for the thread title.


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## davebender (Aug 19, 2013)

Focke Wulf and Heinkel fighter aircraft both had good canopy during late 1930s. I'm surprised RLM didn't insist Me-109F have something comparable when introduced during late 1940.


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## Tante Ju (Aug 19, 2013)

tyrodtom said:


> British pilots claimed the Malcolm hood gave them better overall vision than the bubble canopy on the P-51D.


 
I would like to have some of the stuff they were smoking...


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## GregP (Aug 19, 2013)

Good one Tante Ju!


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## tyrodtom (Aug 19, 2013)

Tante Ju said:


> I would like to have some of the stuff they were smoking...



The Malcolm hood bulged out 7 inches on each side, just like a lot of observation aircraft. That meant they could lean out and look behind and down, they may not have been able to look straight behind as well as a bubble canopy ( even with a bubble you can't see thru the armor plate) but with the Malcolm hood they could see down better, and around the nose better .

There's more than one way to check your 6, it's called S turning.


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## GregP (Aug 19, 2013)

Yes, you are right, but the bubble canopy DID give better all-round vision.


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## vinnye (Aug 19, 2013)

Thanks for posting that prototype up Greg, I had not caught it previously.
Can not understand why that was not used more widely?


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## tyrodtom (Aug 19, 2013)

That prototype radial powered Bf109 may appear to have a regular Bf109 wings and tail, but the fuselage is completely different, much wider, even in the cockpit area.

Look at the angle between the canopy sides and fuselage, compare it with a V12 powered Bf109.


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## GregP (Aug 19, 2013)

It was a prototype powered by a captured Pratt WHitney R-1830 as far as I have found out. I understand the fuselage was modified ... and that's the point. 

It didn't seem all that hard to make major changes for the prototype, so why not make some changes that would have been relatively minor for the production planes? If they can cut down the rear fuselage for a prototype, why not on the line?

I'm sure there were reasons, possibly even valid ones, but the result could have been better for the Luftwaffe pilots had they purseued some of the fixes for the Bf 109.


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## tyrodtom (Aug 19, 2013)

I'm surprised they didn't at least try something like the Malcolm hood. It would have required no redesign of the aircraft itself, probably could have been fitted to aircraft in the field after production.

Maybe Willy Messerschmitt was more interested in selling his new designs (Me209, 309) to the RLM, instead of improving his old products to where the new ones wouldn't be needed.


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## norab (Aug 19, 2013)

making a cut and fit change on a single aircraft is one thing and ties up only a few men and a machine shop. Changing a production line complex machine requires the changing or resetting of hundreds if not thousands of machines in the supply train. If production facilities are at maximum output (like The German war industry was) you have to shut down other projects to divert the resources needed. There are delays while the new parts are designed, logistic systems are set up and the supply system is filled with the new parts. Personnel have to be trained on the new assembly techniques and the bugs worked out to get a smooth rapid assembly system up and running, and during that time you are not producing the aircraft you desperately need


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## bobbysocks (Aug 19, 2013)

i am surprised they didnt at least put a rearview mirror so the pilots could do a quick check of their six every so often without having to kick rudder or turn.


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## davebender (Aug 19, 2013)

I doubt Messerschmitt had any say in the matter. RLM probably looked at the price tag for development and production of Me-109 bubble canopy and declined to fund the project.


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## tyrodtom (Aug 19, 2013)

I've heated and vacuumed Lexan into molds myself, in my garage, it ain't rocket science.

The plexiglass they had in that era, isn't that different.


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## GregP (Aug 19, 2013)

Hey norab,

They made the Bf 109A, B, C, D, F, G, and K. There were three rather complex airframe changes in that series. Putting in a few fixes could NOT have been all that much more difficult, could it?

I think Willy was just stubborn, but have no proof of it other than seeing it in writing in some possibly-questionable publications. So I don't really know, but the changes we're talking about are much easier than going from a Bf 109E to a Bf 109F.


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## Aozora (Aug 19, 2013)

tyrodtom said:


> I'm surprised they didn't at least try something like the Malcolm hood. It would have required no redesign of the aircraft itself, probably could have been fitted to aircraft in the field after production.
> 
> Maybe Willy Messerschmitt was more interested in selling his new designs (Me209, 309) to the RLM, instead of improving his old products to where the new ones wouldn't be needed.



My guess would be the redesigned 'Erla' canopy with Galland armour was considered to be enough of an improvement; interesting though that the Czechs developed a frameless blown canopy for the Avia S-199












speaking of frameless...


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## The Basket (Aug 19, 2013)

I douht a rear view mirror will do much good in a heavily vibrating machine

If an aircraft is in the rear view mirror then he is right behind you and got you. The wingman system was designed so he is looking after your 6. Maybe the 109 was accidently continued so real efforts to improve were never planned.


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## tyrodtom (Aug 19, 2013)

So it could be done, Messerschmitt just didn't take the time to do it.
I wonder if Avia developed that on their own, or if it was in Messerschmitt's plans, but they just didn't get the time to do it?


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## GregP (Aug 19, 2013)

Nice find there Aozora, even though not warbird colors. A bikini is nice but I lean toward the gownless evening strap, myself.


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## GrauGeist (Aug 19, 2013)

Messershmitt did in fact work on a bubble canopy and it was tried on the Me309 prototype. The canopy still opened to the side like the Bf109 models, but it was never adopted.

In order to put a bubble canopy (like the Me262 or Me309) on a Bf109 airframe, you would need to do extensive airframe changes much like they did with the P-51 or P-47 when converted from the "razorback" design.


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## tyrodtom (Aug 19, 2013)

A true bubble canopy would have required major redesign of the fuselage, but just a Malcolm hood design, like the Avia, could have been done with no redesign of the fuselage.
And much better than the Erla version.


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## Aozora (Aug 19, 2013)

tyrodtom said:


> A true bubble canopy would have required major redesign of the fuselage, but just a Malcolm hood design, like the Avia, could have been done with no redesign of the fuselage.
> And much better than the Erla version.



Note that the canopy did slide backwards, so it could have been opened while taxiing or in flight - the inability to even crack open the canopy in those situations was sometimes a complaint of 109 pilots, especially those who had flown Fw 190s. See also: Avia S-199.178 walkaround by Norman Graf
Canopy, starboard 
 Canopy, port 

The head armour was redesigned to be less obstructive on the S-199 and it was, of course, fixed.


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## tyrodtom (Aug 19, 2013)

The original Bf109 had a sliding section on the side, or both sides, but only half of the framed part.

I don't remember if the forward part slid back, or the rear half slid forward. But if you look close at some pictures, you can see the plexiglass grip.


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## Milosh (Aug 20, 2013)

The front panels , sides and top, were movable on non Erla canopies.


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## GregP (Aug 20, 2013)

On the Hispano, it is a small window that pulls in and slides back.

It is the same on our real Bf 109G-6.


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## vinnye (Aug 20, 2013)

I have just read about the Czech built Avia s 199's - and the pilots who flew them did not like them at all.
They could not open the canopy whilst in the air - it had to be jettisoned to bail, the propeller was frequently shot by its own guns, and the narrow landing geart track caused lots of problems.


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## GregP (Aug 20, 2013)

The Jumo made more power at low altitudes than the DB, but less at altitude. So the torque at takeoff was worse than for the BF 109 while the power fell off more quickly as you climbed. 

There were several other aircraft that also could not open their cockpits in flight, including the Fw 190. The Germans fitted the cockpit framing with two blanks 20 mm cartridhes that coiuld be fired to push the canopy to jettison it for bailout. That wasn't the only one, either. Our (museum) Bell YP-59A Airacomet had a standard-looking sliding canopy, but it can't be opened in flight any more than about 2 inches. If you do, you can't close it until you land. There were more ...


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## cimmex (Aug 20, 2013)

GregP said:


> The Germans fitted the cockpit framing with two blanks 20 mm cartridhes that coiuld be fired to push the canopy to jettison it for bailout.


Sorry, there was only one cartridge for jettison the hood at the Fw 190.
cimmex


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## GregP (Aug 20, 2013)

Thanks Cimmex. Can I assume it was located at the top center, or was it located at the bottom near the rail on one side? I have never seen the cartridge location shown on a cutaway and the description I read was 20+ years ago.


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## cimmex (Aug 20, 2013)

Found a pic
cimmex


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## bobbysocks (Aug 20, 2013)

The Basket said:


> I douht a rear view mirror will do much good in a heavily vibrating machine
> 
> If an aircraft is in the rear view mirror then he is right behind you and got you. The wingman system was designed so he is looking after your 6. Maybe the 109 was accidently continued so real efforts to improve were never planned.



a lot of mustang pilots had rear view mirrors. had they been a waste of time i doubt they would have left them on.


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## GregP (Aug 20, 2013)

Thanks Cimmex. Can I assume the cartridge is #15?


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## FLYBOYJ (Aug 20, 2013)

bobbysocks said:


> a lot of mustang pilots had rear view mirrors. had they been a waste of time i doubt they would have left them on.


Depends who you talk to - some liked them, some put them on then removed them.

http://www.ww2aircraft.net/forum/technical/rear-view-mirrors-fighters-1315.html#post66041


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## Milosh (Aug 20, 2013)

GregP said:


> There were several other aircraft that also could not open their cockpits in flight, including the Fw 190. The Germans fitted the cockpit framing with two blanks 20 mm cartridhes that coiuld be fired to push the canopy to jettison it for bailout.



The 20mm blank was used to break the 'suction' that held the canopy in place even after the jettison lever had been engaged.

The 20mm is located between #11 and #16.


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## Aozora (Aug 20, 2013)

GregP said:


> Thanks Cimmex. Can I assume the cartridge is #15?



Looks more like #14 which fired into the base of 16; from memory an MG 151 cartridge was used?


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## alejandro_ (Sep 3, 2013)

I have read the whole discussion. I haven't been able to find much information on this subject. Some captured Messerschmitt documents can be found at the NA at Kew, but no comment is made on bubble canopy. In other forums I read that Willy Messerschmitt did try a few but nothing came out of it. I can think of a few reasons:

- There was a fuel tank behind pilot. If bubble canopy is added it has to be trimmed, reducing an already low fuel capacity. You could make up by installing a modified fuel tank, or adding new ones, but then you can have issues with CoG. 
- Time, which Germany did not have.
- Effects in directional stability. P-51C/D needed some modifications after bubble canopy was installed.

Finally, I had a look at Stepanets' book on Yakovlev fighter aircraft. He was a designer for the company in WW2 and provides many details on the fighter development. He does comment on the Yak-1 with improved visibility but it did not seem to be very complicated.


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## zoomar (Sep 3, 2013)

Germans had all-round vision canopies since the He 112, but these - as well as later canopies on the Me 262 and Me 309 were not true bubbles. They were framed with the center section hinged for pilot access. Was the entirely clear view canopy on the Fw 190 V1 or early Fw 187 true bubbles in manufacture? Actually, is the bubble canopy really that much better than a clear-view canopy merged into a built up rear fuselage? It's worth noting that the final Lavochkin piston engined fighters reverted from an all-round vision canopy in the La-5 and 7 series to a canopy tailored to a raised upper fueslage, probably with no better all-round visibility sported by the Bf 109K. Of for that matter, the He 100 that followed the He 112 abandoned the all-round clear vision cockpit.


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## stona (Sep 3, 2013)

The fundamental problem for the Bf 109 hood was that it hinged rather than sliding. It was a simple task to fit a blown hood to a Spitfire, not so a Bf 109.
Cheers
Steve


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## spicmart (Sep 3, 2013)

Until the E-model the 109 sported another kind of canopy than the later versions.
Why did they change it? Which canopy had more room? 
It appears to me that the earlier ones roomy.


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## paradoxguy (Sep 3, 2013)

A tangential question--why did Messerschmitt persist with hinged canopies that opened to one side or the back with their fighters and zestorers, even the Me 410 and Me 262? Did hinged canopies have an inherent functional advantage over sliding ones, or were they just simpler to manufacture?


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## GregP (Sep 4, 2013)

Hi Steve,

That's simple ... change the hinges to slides. No big deal. If you're going to modify it anyway, make it easier on yourself.


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## GrauGeist (Sep 4, 2013)

spicmart said:


> Until the E-model the 109 sported another kind of canopy than the later versions.
> Why did they change it? Which canopy had more room?
> It appears to me that the earlier ones roomy.


The cockpit of the Bf109 was always cramped and on the border of being claustrophobic.


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## GregP (Sep 4, 2013)

I can tell you from experience that if you're in it face first working on the lower firewall ... it is VERY claustrophobic and also tough to get out of! I needed help from two guys. 

We were attaching new landing gear brackets and it was quite unconfortable being upside down trying to tighten the nylocks.


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## stona (Sep 4, 2013)

GregP said:


> Hi Steve,
> 
> That's simple ... change the hinges to slides. No big deal. If you're going to modify it anyway, make it easier on yourself.



But again that's not as easy to do as to write! It could be done of course. I don't know what modifications would be required to the fuselage/sills, apart from the obvious runners. You'd have to alter the rear section, at least to move the radio mast. It would be a lot simpler than developing a low back 

There doesn't seem to have been any will, either at the manufacturer or the RLM to make such changes.

As someone has pointed out Messerschmitt persisted with hinging hoods on several types. Maybe that's just the way their canopy guys did it. Some allied types had some odd means of access too....."car door" Typhoon springs to mind. 

Cheers

Steve


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## Rufus123 (Sep 4, 2013)

I know these numbers would be impossible to come up with but I wonder how many planes and pilots were lost due to lack of visibility?


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## stona (Sep 4, 2013)

Rufus123 said:


> I know these numbers would be impossible to come up with but I wonder how many planes and pilots were lost due to lack of visibility?



No way of knowing, but a substantial percentage of pilots were shot down by an assailant who they never saw, for one reason or another.

Steve


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## Shortround6 (Sep 4, 2013)

Nobody knows and there is no way to find out, but it obviously was enough of a problem that _many fighters_ were converted to have better reward vision and many/most new ones had canopies offering good reward vision. Exceptions usually being the "interceptors" which were tasked with making one or two firing passes at bombers ( early 1950s jets) and NOT engaging in fighter to fighter combat.


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## tyrodtom (Sep 4, 2013)

We seem to think those pilots sat in those aircraft with no rear visibility and did nothing.
It probably didn't take them long to think of S turning to check their tail, plus they always tried to operate in at least pairs.
Most pilots are quite capable of seeing the faults in their aircraft, and thinking of ways around those shortcomings.


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## tyrodtom (Sep 4, 2013)

We seem to think those pilots sat in those aircraft with no rear visibility and did nothing.
It probably didn't take them long to think of S turning to check their tail, plus they always tried to operate in at least pairs.
Most pilots are quite capable of seeing the faults in their aircraft, and thinking of ways around those shortcomings.


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## Rufus123 (Sep 4, 2013)

tyrodtom said:


> We seem to think those pilots sat in those aircraft with no rear visibility and did nothing.
> It probably didn't take them long to think of S turning to check their tail, plus they always tried to operate in at least pairs.
> Most pilots are quite capable of seeing the faults in their aircraft, and thinking of ways around those shortcomings.



While this may be true it sounds like S turning would be more work, use more fuel, and might be troublesome when doing things like attacking a bomber.

Anything that made it easier would have to help. If large numbers of planes when down where the attacker was never seen this alone might not have been enough.


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## tyrodtom (Sep 4, 2013)

If you read accounts from most fighter pilots, they made it a point to do very little flight in combat areas in which they were not turning, banking, anything but fly a predictable course.
Some even flew out of trim, in a skid, or slip. Just to make themselves a harder target.
Survival in a combat enviroment is always about doing things that may seem troublesome, when you're not getting shot at.

And just because you have a bubble canopy doesn't mean you don't have to s turn in a combat area. A bubble canopy only enables you to see behind and above, you still can't see behind and below, without s-turning.


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## razor1uk (Sep 4, 2013)

When it came to gun/cannon/aimed projectile dogfighting, fooling the enemy if only of a split second was a skill self taught after many engagements. 

If making the enemy thought your going in a slightly different vector, track and angle and or speed, it could get him to miss-target you, and in such close quarter aerial fights, every advantage and slight of stick (ne hand,) gives you another chance - to what is/was of death, life, wounding, etc, if only to live 1 second longer.


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## vinnye (Sep 4, 2013)

Can't completely trust my memory, but I think Hartmann said in one interview that he regularly attacked from below and behind. 
This goes a long way to negate the extra visibility gained from bubble canopies etc.


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## Rufus123 (Sep 4, 2013)

vinnye said:


> Can't completely trust my memory, but I think Hartmann said in one interview that he regularly attacked from below and behind.
> This goes a long way to negate the extra visibility gained from bubble canopies etc.



I thought the visibility was more of an asset for the defensive than it was the offensive. Makes it easier to see who is behind you.


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## tyrodtom (Sep 4, 2013)

While on the subject of Hartmann, it should be noted he shot down all his victims with a Bf109, and never lost a wingman.
Though he did get shot down himself, many times, it was usually from flying through his victim's debris.

When you think of all the exposure he had to getting shot down, he and his wingmen evidently though of some way around the lack of rearward vision..


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## Rufus123 (Sep 4, 2013)

tyrodtom said:


> While on the subject of Hartmann, it should be noted he shot down all his victims with a Bf109, and never lost a wingman.
> Though he did get shot down himself, many times, it was usually from flying through his victim's debris.
> 
> When you think of all the exposure he had to getting shot down, he and his wingmen evidently though of some way around the lack of rearward vision..



He might have, but what about all those others that did get shot down not seeing who was shooting at them.


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## Milosh (Sep 4, 2013)

tyrodtom said:


> While on the subject of Hartmann, it should be noted he shot down all his victims with a Bf109, and never lost a wingman.
> Though he did get shot down himself, many times, it was usually from flying through his victim's debris.
> 
> When you think of all the exposure he had to getting shot down, he and his wingmen evidently though of some way around the lack of rearward vision..



It also should be noted that the only alternate single engine fighter available to him was the Fw190.


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## tyrodtom (Sep 4, 2013)

I'm sure all of us have read many accounts where the victim was flying around in the sky like he thought he was the only aircraft for miles.
Better rearward vision will help nothing if you're not using it.
That's why so many pictures of WW2, and WW1 pilots show them with silk scarves. Without those scarves their necks would be raw from their jacket collar, from their constant neck movement. 
The smart ones knew they needed all round vision, everywhere, not just behind and above, and did what they had to do to get it, or they had short flying careers.


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## tyrodtom (Sep 4, 2013)

double post


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## Rufus123 (Sep 4, 2013)

tyrodtom said:


> I'm sure all of us have read many accounts where the victim was flying around in the sky like he thought he was the only aircraft for miles.
> Better rearward vision will help nothing if you're not using it.
> That's why so many pictures of WW2, and WW1 pilots show them with silk scarves. Without those scarves their necks would be raw from their jacket collar, from their constant neck movement.
> The smart ones knew they needed all round vision, everywhere, not just behind and above, and did what they had to do to get it, or they had short flying careers.



I thought the whole point of a bubble canopy was to looking around a lot but have an unobstructed view when doing all of this head turning, it does not stop you from doing S turns as well.


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## Shortround6 (Sep 4, 2013)

Maybe your S turns don't have to be as big?


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## bobbysocks (Sep 4, 2013)

i read an account where the mustang pilot was chasing a couple 109s. he said you could see them kicking rudder into a mild slips. they did that so they could see behind them. they would slip quickly from one side then the other. you arent going to want to make big turns if there is a decent chance someone closing in on you from a distance you or else you will be setting yourself up as the target for a great deflection shot when they cut inside you.


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## The Basket (Sep 4, 2013)

It seems that bubble canopies were introduced for a reason.

Therefore...it was because somebody thought it was a jolly good idea to see behind you.

The mirror issue was a quote from none other than Gunther Rall who said he had a mirror in his 109 in the beginning but if he saw someone in the mirror then it was too late as he was about to be shot down! He did mention the poor vision in the 109 hence the mirror.


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## tyrodtom (Sep 4, 2013)

A bubble canopy only fixed one part of the vision problem, big areas of the sky is still blanked out by the fuselage, wings, and horizontal stabilizer of a low wing fighter.
You still have to manuver around to clear those areas.

Flying with you "head up, and locked " is still the main factor in mid air collisions, in civilian aviation.


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## GregP (Sep 4, 2013)

Sort of common knowledge but, in a combat zone today, you don't fly straight and level for longer than 30 seconds, even with RWR and all the bells and whistles.


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## Rufus123 (Sep 5, 2013)

tyrodtom said:


> A bubble canopy only fixed one part of the vision problem, big areas of the sky is still blanked out by the fuselage, wings, and horizontal stabilizer of a low wing fighter.
> You still have to manuver around to clear those areas.
> 
> Flying with you "head up, and locked " is still the main factor in mid air collisions, in civilian aviation.



Of course it is not going to solve all vision problems. The pilot also still has to do his job. Maybe I am misunderstanding but your posts made it seem to me that the you think the bubble canopy was a waste? Would you want them to get rid of the bubble canopy?


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## stona (Sep 5, 2013)

Any means of ensuring better vision gave an advantage. Even a small advantage could be important. The story of the Malcolm Hood and it's rapid adoption or copying by other air forces and manufacturers (Vought) is a good example.
You can have the best 360 degree vision in the world, but it is pointless if you don't use it.
Cheers
Steve


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## tyrodtom (Sep 5, 2013)

I'm not saying the bubble canopy is a waste , but I think we might be overstating the need.
A good example of a single engine aircraft with outstanding rearward visibility is a IL-2, it had a rear gunner facing backward, with nothing to do but scan the sky to the rear.
But because a lot of IL-2 pilots were inexperienced, flew steady flights, trusting their rear gunner to see anything coming from the rear. Not thinking of the big area blanked out by the rear fuselage and tail.
The more experienced Luftwaffe pilots, seeing a IL-2 would just close the range in that blind spot, from below.


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## vinnye (Sep 5, 2013)

That is what Hartmann said he did.
Maybe too much was made of the WW1 saying "Beware of the Hun in the Sun", maybe it should have been adapted to the catch phrase used in children's pantomimes - "He's behind you!"


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## GregP (Sep 5, 2013)

When we have thought the bubble canopy was overrated, the next -generation conflict reminded us it wasn't.

We got the bubble canopy in WWII and kept it in Korea (SOON after WWII). Then we went to the first-generation supersonic planes like the MiG-21, F-8 Crusader, A-4, F-4, F-105, etc. Some LOOK like bubbles until you actually try to look out of the back and see the fuselage is rasied so you can't see behind you. The enemy in Viet Nam reminded us of it, and the next-gen (F-14, D-15. F-16) HAVE bubble canopies. So does the Raptor. 

The Soviets had an entire generation without bubbles. Think MiG-25, MiG-27, Su-25, Su-24. etc. The new Russian fighters all have bubble canopies.

I don't think they were overrated at all. Giving the pilot the option to look behind him is imperative for survival. Whether or not he USES it is another question.


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## Shortround6 (Sep 8, 2013)

to be fair some of those 1950s jets were never intended to be dog fighters. Like the F-102 and F-106. They were intended to intercept bombers that had no escorting fighters. The F-105 has an "F" number but it was a bomber (primary role was nuclear attack platform, air to air was a secondary capability). No air to air fighter needed an internal bomb bay that could later house a 325 gallon fuel tank. 

the "perceived" need (not actual) to hit mach 2 or close to it drove aerodynamics to override reward vision.


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## GregP (Sep 8, 2013)

The "whys and wherefores" don't matter.

The simple fact is when we abandoned the bubble canopy, we were rudely reminded that we shouldn't have done that. There are NO top-line fighters without them today. So ... we must have learned that along the way, and SHOULD have learned it very well indeed in WWII.


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## N4521U (Sep 9, 2013)

Besides the Germans probably thought the pilot looked like he was in a clear Joo Joo Bee.


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## alejandro_ (Sep 9, 2013)

I have been looking at diagrams of aircraft that received bubble canopy in latter version. None had a fuel tank behind pilot:

- Spitfire had main fuel tank in a section between cockpit and engine.
- Yakovlev aircraft had them in the wings.
- P-47s had them below pilot in the lower section of the aircraft (can someone confirm?).

If fuselage in Bf 109 is trimmed, you lose the fuel capacity and you have to lose range (which was already short) or relocate somewhere else (CG issues).

Another -more simple- reason pointed out in other forums was that Bf 109 was supposed to be phased out of production, thus it made no sense to develop time consuming improvements.


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## Tante Ju (Sep 9, 2013)

alejandro_ said:


> If fuselage in Bf 109 is trimmed, you lose the fuel capacity and you have to lose range (which was already short) or relocate somewhere else (CG issues).



I don't think so, the fuel tank top ends somewhere at the lower canopy line, so if you trim down the real fuselage it would probably not effect the fuel tank much. And if it looses a bit in the top, you can always make it stretch a bit more towards the rear.

Besides after restoring the previous rear view with the fitting of the Galland Panzer, I do not think they would though that a further redesign and associated risk would be warranted. The Me 109 also had weak directional stability, perhaps this was a concern.

It would be interesting to know if this question was discussed at company meetings though, but lets not forget that - apart from Fw 190 - there were not many examples of bubble canopies until 1944. I am not sure when Typoon got one.


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## paradoxguy (Sep 9, 2013)

alejandro_ said:


> I have been looking at diagrams of aircraft that received bubble canopy in latter version. None had a fuel tank behind pilot:
> 
> - Spitfire had main fuel tank in a section between cockpit and engine.
> - Yakovlev aircraft had them in the wings.
> ...



What about the North American P-51 Mustang? It did not have a bubble canopy fitted until the D-series, and I recall the B- and C-series (and later) had a large fuel tank behind the pilot's seat.


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## stona (Sep 9, 2013)

Tante Ju said:


> I don't think so, the fuel tank top ends somewhere at the lower canopy line, so if you trim down the real fuselage it would probably not effect the fuel tank much. And if it looses a bit in the top, you can always make it stretch a bit more towards the rear.



This is exactly what I mean when I say people write "just" do this or that without really knowing what the ramifications might be.
I'm not picking on you Tante Ju  It happens a lot in all sorts of threads. 
I only caution against it because my research into various aircraft shows that modifications are never as simple to do as to write and are often extremely difficult. They often need months of development and testing before they appear in production aircraft. It's why places like Rechlin and Boscombe Down existed. 
Cheers
Steve


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## Tante Ju (Sep 9, 2013)

No problem at all stona, we are guessworking here. I _guess _  so did the engineers in the 1930s - I wonder how many 'oops' were uttered by observing engineers when the test pilot was seen descending on a parachute... many times their calculations could not account for unseen problems like mach flutter, harmonic vibrations and so on..


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## stona (Sep 9, 2013)

Absolutely correct. I've just been reading about problems with the elevator/elevator control circuit that led to the tail breaking off early Typhoons at the transport joint. It took several fatalities before finally the real cause was found. Oddly enough harmonic vibrations was one of the possibilities discussed, and eventually discounted  In the meantime Hawker engineers kept going over their structural calculations and reporting that the structure was sound.

I appreciate you taking my post in the spirit in which it was intended!

Cheers

Steve


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## Kryten (Sep 9, 2013)

stona said:


> Absolutely correct. I've just been reading about problems with the elevator/elevator control circuit that led to the tail breaking off early Typhoons at the transport joint. It took several fatalities before finally the real cause was found. Oddly enough harmonic vibrations was one of the possibilities discussed, and eventually discounted  In the meantime Hawker engineers kept going over their structural calculations and reporting that the structure was sound.
> 
> I appreciate you taking my post in the spirit in which it was intended!
> 
> ...




I can shine a little light on this as I had a discussion with an old gent I knew who worked for Hawker and was part of the team trying to solve this!

He claimed the real problem was the elevators going into compression, you could move the elevators as much as you liked, once over the threshold they had no effect, the pilot then would throttle back trim out and pull like hell on the stick trying to recover from the dive, once the airspeed fell below the threshold the elevators suddenly regained authority and sent a huge load reversal through the fuselage breaking the transport joint!

It only happened in those circumstances, which was why they had such trouble finding the cause, he said they only really got to the bottom of it after the war when compressibility became understood!

Or that's the story I was told anyway!


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## stona (Sep 9, 2013)

The official cause of the accidents was a failure of the elevator mass balance mounting brackets. The unbalanced control surface would flutter uncontrollably and impose unanticipated and enormous loads on the entire tail unit which then broke at the weakest point, the transport joint.
The cure was complicated. The following is from Mason.
1) The mass balance bracket was strengthened immediately as an interim measure that was retained.
2) Needle bearings were fitted in the elevator counter shaft. This enabled circuit tension to be increased without increasing control friction. Control backlash was virtually eliminated.
3)A correlation between the elevator mass balance moment and the tendency of the aircraft to tighten up in a turn was also established. A series of tests were flown with different elevator mass balance weights and varying inertia weights applied to the control column.
4) An 8lb elevator mass balance and a 16lb control column inertia weight were fitted.
5) The geared balance tab was changed to an ordinary adjustable trim tab and the damping cords were removed on the rudder.

Squadron Leader Beamont (NOT Beaumont!) then did diving trials up to 500 mph and pull outs in an effort, in his own words to "see if the tail would come off". They don't make them like that anymore. It didn't, luckily for him, and he also found that turns up to 61/2 g could be pulled at 5,000ft with no tendency to tighten up.
Strain gauges recorded that even in "harsh" pull outs at the highest attainable speeds no excessive loads were produced in the elevator mountings or transport joint.

Cheers

Steve


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## Ivan1GFP (Sep 11, 2013)

alejandro_ said:


> I have been looking at diagrams of aircraft that received bubble canopy in latter version. None had a fuel tank behind pilot:
> 
> - Spitfire had main fuel tank in a section between cockpit and engine.
> - Yakovlev aircraft had them in the wings.
> ...



The later versions of the Spitfire Mk.IX and Mk.XVI actually gained fuel tanks behind the cockpit often along with a bubble canopy though in the Pilots Manual, it states NOT to fill that particular tank.

- Ivan.


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## Ivan1GFP (Sep 11, 2013)

This thread has explored a lot of different ideas.

Way back in the beginning of the Me109 Improvements thread, I proposed that the tail be lowered to improve the ground angle. At the time, I was also thinking that it would help visibility a bit. 

I have never seen a flying Me109 in person, but some of you probably have. Does the 109 fly a bit nose down like the FW 190? If so, then the tail would still block a lot of the view aft even if a bubble canopy were installed.

Here are a few other considerations:
The framing on the 109G and later was made thicker so that the cockpit could be pressurised even though most of the aircraft were not so equipped. The Germans were willing to lose even more visibility in ALL of their 109s with the heavier framing so that a few could received pressurised cockpits. A hinged canopy would also be simpler to seal than a sliding canopy.

With the original hinged canopy, no one is really inclined to taxi the aircraft with the canopy open. With a sliding canopy, perhaps this would be done. If this were done, with a heavy armoured canopy, perhaps the rails would need a fairly sturdy structure to be bolted to and this would be difficult with the design of the 109 aft fuselage.

Just a few different ideas.
- Ivan.


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## stona (Sep 11, 2013)

Rear view was, and remained until the sliding one piece hood, a serious problem on the Typhoon. It was a _major_ consideration for the RAF. Why the Luftwaffe was prepared to sacrifice this only it would know.
Cheers
Steve


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## Tante Ju (Sep 11, 2013)

Ivan1GFP said:


> With the original hinged canopy, no one is really inclined to taxi the aircraft with the canopy open. With a sliding canopy, perhaps this would be done.



Or perhaps this was the reason why sliding wind panels were present on the hinged canopy?  The Erla type of course, could not be opened this way, but also had only marginal framing.


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## bobbysocks (Sep 11, 2013)

GregP said:


> I don't think they were overrated at all. Giving the pilot the option to look behind him is imperative for survival. Whether or not he USES it is another question.



i agree and have never read a pilot complain or one state he didnt like a bubble canopy. even at that they installed a rearward radar on later 51s ( and probably other ac too ) to give advance warning if someone was closing in on you. my dad said there were a couple problems with it to his way of thinking. 1) like the mirror comment made by rall ...once the bell went off the EA was probably already too close. 2) it was turned off most of the time because guys were flying in formation and the bell would constantly be going off. in the heat of battle most pilots forgot to turn it on....hell a lot of them didnt remember to flip on their gun switches until they pulled the trigger and nothing happened. but the thinking i guess was if it saved a few pilots it was worth it. and that is the way i look at a better canopy on a 109....


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## stona (Sep 12, 2013)

The Typhoon, canopy saga culminated in a report of actions by the Duxford wing on 19th August 1942. The Typhoons were bounced from above an behind three times, twice by Fw 190s and once by Canadian Spitfires. 
There was a "clamour" for a better canopy. The current Stage B canopy incorporated flat windscreen quarterlights and did away with the small clear panels let into the structure behind the armour in favour of Perspex. The car door was retained. It was an improvement over the earlier type(s) but pilots reported that whilst straining to look over their shoulder and around the armoured head rest, vision through the rear Perspex at such an acute angle was so distorted that any aircraft within a 40 degree cone in the rear hemisphere was scarcely visible and impossible to identify, even if seen.
The new "tear drop" one piece sliding canopy was _already being tested _at Langley, but fitting it required such extensive alterations, including removing the car door, that it would be months before it appeared on production Typhoons and others were retro fitted.
It is important to note that the poor rearward vision from the early Typhoon canopies was considered a problem both by the pilots that flew it and the manufacturer who went to great lengths (and expense) to address the problem. It entailed major structural alterations at every stage of the progression towards the one piece sliding canopy of the late war versions.

Why the Luftwaffe appears to have had a different attitude I know not. I would imagine a pilot flying a Bf 109 after having flown a Fw 190 would at least comment on it, but it seems they just got on with it. Maybe they knew that the RLM would not authorise major surgery on the Bf 109 mid production.

Cheers
Steve


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