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ImpStarDuece
04-30-2005, 01:42 AM
I have just finished reading Book 1 of the Osprey Aviation Elite serise and was suprised to find this paragraph in the book;

Top of p.76

"Re-equipment with the Bf 109F meant that the Gweschwader was more than holding its own against the RAF's new Spitfire Mk V, but the intergrity of the Friedrich's aerodnamically refined airframe had long been suspect. And despite early problems with its tail unit being resolved by the addition of external stiffeners, unexplained losses continued to occur. The, on 28 June, the wing of a JG 26 machine collapsed during a dogfight, killing 31-victory Expert Oberleutnant Gustav Sprick.

Four days later late FG2 was celebrating the award of the Oak Leaves to their Kommodore for his achieving 40 comfirmed kills. But the very next afternoon, at 1525 hours on 3 July, Hauptmann Wilhelm Balthasar was to lose his life in almost identical circumstance to 'Mickey' Sprick. The wing of his F4 reportedly sheared off when he attempted an evasive spiral dive manoeuver during combat with a group of Spitfires."

End of quote.


Does anyone else have additional information on wing failures in the 109 F2 or F4? None of my other sources have mentioned this and it is the first I have heard of it.

F19_Ob
04-30-2005, 03:48 AM
Hello mate.
I have no source to this piece of info but it atleast comes from several books I have read during the years.

It was about an 109 F pilot who lost his wing in such an above described spiral dive.
The pilot died but his wingmates thought he had taken some hits in the wing in an earlier sortie and perhaps that had caused structural damage.


cheers

LeadSpitter_
04-30-2005, 07:21 AM
Bf 109 F-4 W.Nr. 7066 was the aircraft Hauptmann Wilhelm Balthasar lost his life in.

mynameisroland
04-30-2005, 07:55 AM
This problem is quite well documented I am at work now so i dont have sources but the 109 F series initially did suffer from structural failures.

I have only ever heard about this one here, I can only assume the author has confused the tail with the wing?

The failures relate to the redesigned tail plane. The struts that supported the earlier 109 series tail were removed on the F series onwards. The refinement was stressed to absorb the correct amount of stresses during manuvers ect but unfortunately there was a problem which only arose at certian airspeeds which buffeted the tail. These buffets corresponded exactly to the vibrations from the Me 109's DB 601 E unit at certain HP settings and caused the tail unit to sheer off !

Not very good if you are trying to evade a Spitfire. 109 F fighters were ground if i recall until this problem was identified and rectified by the introduction of two wleded strenghteners just forward of and below the tail plane. There were no subsequent problems associated with the design after that modificication.

Rgr

LeadSpitter_
04-30-2005, 08:02 AM
Originally posted by mynameisroland:
This problem is quite well documented I am at work now so i dont have sources but the 109 F series initially did suffer from structural failures.

I have only ever heard about this one here, I can only assume the author has confused the tail with the wing?

The failures relate to the redesigned tail plane. The struts that supported the earlier 109 series tail were removed on the F series onwards. The refinement was stressed to absorb the correct amount of stresses during manuvers ect but unfortunately there was a problem which only arose at certian airspeeds which buffeted the tail. These buffets corresponded exactly to the vibrations from the Me 109's DB 601 E unit at certain HP settings and caused the tail unit to sheer off !

Not very good if you are trying to evade a Spitfire. 109 F fighters were ground if i recall until this problem was identified and rectified by the introduction of two wleded strenghteners just forward of and below the tail plane. There were no subsequent problems associated with the design after that modificication.

Rgr

But that was the tail being reinforced a completely different incident, as you know this happened to many gustav varients as well which theres records of and as the document ImpStarDuece posted. It also happened to the fredrick after the tail reinforcements were made.

So how can you say There were no subsequent problems associated with the design after that modificication when in fact there was and on G varients as well both wing structural failure and different incidents of the tail sherring off of the 109 in north africa from british and american pilots.

Theres many pilot claims of this happening to the the g6 as well as the k4

ImpStarDuece
04-30-2005, 08:08 AM
The book refers to two seperate wing failures and specifically mentions that the problems with the tail plane had already been fixed.

I highly doubt that the author is confused if he refers to the tail problem and then goes on to note two WING failures.

What got me interested in this was the amount of stuff written about the Typhoon and its structural failures. If you read a lot of the things published you might be forgive for thinking hundreds of Typhoons were lost because of tail failures. I was HIGHLY suprised when I learnt that there were just 24 know failures and many of these were attributed to the fact that the Typhoons were often diving above 540 mph.

I was mostly looking for more information on the wing loss problem and there are some pretty knowledgable 109 drivers here.

mynameisroland
04-30-2005, 08:10 AM
The book i am reffering to which is Messershmid 109 F - K series or something like that covers the design and prodcution aspects of the series from F 1 onwards. They tested the 109 in terminal velocity dives diving repetedly to over 900k and found there to be no structural problems. I think this book has info from one of the actual 109 designers so and has origional test data. I will try to post some of it on mondy perhaps.

The strenghtener was sufficient for the problem associated with the tail falling of. Now as for structural failures for the G series - why not ? Reduction in build quality (sabotage also) and the fact that aircraft of the period always had their unknowns - even todays planes are tested to death but problems can mysteriously arrive. I dont think the 109 had any more structural problems that arose to flying accidents than other WW2 fighters. Remember of 35000 of them flew on 100,000's of ops so there was always going to be unaccountable losses.

Rgr

LeadSpitter_
04-30-2005, 08:18 AM
I have that book as well and its pretty unaccurate BF109F/G/K

You notice there is not original graphs but recreated ones which dont so source or ID# of the original test charts.

This is the same book so many in orr post information from but dont look at the whole picture or many other books especially romanian polish finnish italian etc

Every book seems to have different charts values of the same ac some sourced some not.

3.JG51_BigBear
04-30-2005, 08:41 AM
For what its worth, this is from JG26 Top Guns of the Luftwaffe by Donald Caldwell

A second structural problem did not appear until the aircraft had actually entered combat. Airplanes began returning from missions with ripples in their wing skins, indicative of hidden damage to the wing structure. Apparently neither the factory nor the RLM though the problem was serious, but after the wing spars of several aircraft collapsed in flight, trapping the pilots in their cockpits, Oblt. Schroedter, technical officer of the Third Gruppe, borrowed some straing gauges from Rechlin and ran his own experiments. The weak areas in the wing were identified, and local stiffeners were designed. These could not be applied in the Geshwader shops, however, and Schroedter was given the job of flying obviously damaged aircraft to the repair facility in Antwerp to have their wings replaced.

How would you like to be the TO that had to fly the "obviously damaged aircraft."

LeadSpitter_
04-30-2005, 08:59 AM
great point bigbear, and I agree thats probally what happened.

Same reason why aluminum airframes have certain life expectantcies today before they become fatigued and loose structural strenght after time.

Post that to kurfurst btw bigbear http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

I seen a video of a p-38 tail booms bent like a bananna in speed tests trying to break the sound barrier, the buffeting would throw them into a voilent flopping stall and recovery would bend both booms, some crazy stuff.

You have to admit the 109 airframe was very weak similiar to the ki43s aluminium construction fuselage and wingspars. The 190s wings as well were not built to take hits and spars are very wide apart.

In the hundreds of guncamera footage clips of 190s wings blowing off from a short burst 2-3 second of .50 cals. Its from the api's hitting the 20mm casings which is what causes the wings to be sherred off in 10-12 strikes, the oxygen tanks being hit caused the same thing to happen.

Back to the 109F i think oleg should have never added the additional 200-300kmph extra dive speeds to almost all the ac. The game was much better before when yaks broke up at 650, 109s 750-800.

Theres really no noticable dive advantages still just max breakup speed as the only advantage which was limited significantly.

I think they should add the same wing snap like the mustang has as low as 560 to all ac to stop the extreme stick yanking in online play. Maybe do something like janes wwii add a creaking metal fatigue sound before its going to happen to make simulate structural fatigue.

Who knows maybe they are working on these issues in 4.0 but i somehow doubt it.

JuHa-
04-30-2005, 09:31 AM
Kesselring (commander of Luftflotte 2) sent out on 1941 a 25-point list of known problems, and
it states that:

a) Tail structure should be enforced as a plane has lost it's tail in flight

b) Deformation of the wings is experienced and the wings require constant maintenance.

c) The main bolts that hold the wings to the
fuselage are prone to come off.

(and 22 other things)
W. Messerschmitt replied that these issues are already known and solved at factory. Moreover,
the subcontracting companies were to blame on
part of the issues...

Unfortunately I don't have the dates of these letters, so can't really say what models were
affected. I'd suspect that early F4 would be.

Another thing is, that early E models did have a real problem with their wings, and some
restrictions ordered by high command is documented.
(Genst. 3.Abt.L.In 5 Nr. 335/39 geh. 15.2.1939)

These problems were rectified too, but
the legend lived a very long life in wartime propaganda.

I remember too that there is one or two often quoted instances about F losing its' wing, but
not like it was a common occurance. Also, the letter states the deformations as a known
issue, but not the total failure of the wing.
Ie. if service wasn't properly done, the F really could break up.

And too, this quoted failure happened at diving
turn, which is the perfect place to put maximum
G on the airframe.

So I say yes, wing could snap off in specific conditions: already deformed wing and
neglected maintenance.

In game, the policy was to have factory-spec
machines, right? Not war-weary or worn out ones?

F2 with it's tail coming off at high stress would be justified, IMHO.

p1ngu666
04-30-2005, 10:27 AM
Originally posted by JuHa-:

c) The main bolts that hold the wings to the
fuselage are prone to come off.



http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

the tails falling off typhoons was due to vibrations, not any lack of structural strength. tiffy was very strong and juglike http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

ViolentVolVo
04-30-2005, 11:52 AM
the tails falling off typhoons was due to vibrations, not any lack of structural strength


eeeeh if the plane breaks up due to vibrations isnt that a structural problem???????

http://forums.ubi.com/images/smilies/35.gif

Aztek_Eagle
04-30-2005, 06:05 PM
it was what killed molders aswell, those idiots!

LEXX_Luthor
04-30-2005, 08:58 PM
ViolentVolVo::
eeeeh if the plane breaks up due to vibrations isnt that a structural problem???????
http://forums.ubi.com/images/smilies/35.gif
pingu said Structural Strength, which in this case probably had no effect on the vibration effects which were probably not expected, or designed for. Its like getting a boby builder drunk and then taking his money purse while he sleeps like Baby in diapers, the athlete's Structural Strength won't help him, the alchohol goes around the Strength, like unexpected vibrations can. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Well, that's my best parable for this.

PBNA-Boosher
04-30-2005, 09:40 PM
It's what happens when too much of the same metal is used in a building project. If it reaches its natural frequency, it will shake itself to its own breaking point. It's like a singer matching the frequency of a crystal glass that's been hit with a fork. The glass will shatter, as would the plane in this case. The problem can easily be corrected by adjusting the alloys in the metal, or adding different types of metal into the components.

Ruy Horta
05-01-2005, 03:44 AM
Originally posted by Aztek_Eagle:
it was what killed molders aswell, those idiots!

M├┬Âlders was killed as a passenger in a He 111, through a combination of bad weather and engine failure.

On the off chance that your were serious

p1ngu666
05-01-2005, 07:09 AM
Originally posted by PBNA-Boosher:
It's what happens when too much of the same metal is used in a building project. If it reaches its natural frequency, it will shake itself to its own breaking point. It's like a singer matching the frequency of a crystal glass that's been hit with a fork. The glass will shatter, as would the plane in this case. The problem can easily be corrected by adjusting the alloys in the metal, or adding different types of metal into the components.

yep, u can shake a structure to pieces, problem hawker had was planes could dive very well with no problems, but under certain conditions they would fall apart.

test pilots found they hadto do set routines, at set times. if they found the problem it was expected they would die, so ppl on ground would look and say, 12.05, diving then turning engine off (which was one of the tests)

iirec there was some vibration from the elivator that was the main reason

ImpStarDuece
05-01-2005, 07:42 AM
Structural tests were carried out on the Typhoon by the Royal Aircraft Establishment (RAE) the Aeroplane and Armament Experimental Establishment, the RAF, the Ministry for Aircraft Production and Hawker itself to try and establish the cause of the failures.

The structural failures themselves changed in nature during the course of the war. The first serious accident with the Typhoon was the death of J.F. Deck from carbon monoxide poisioning on November 1, 1941. The upshot of this was that Typhoon pilots wore oxygen masks from engine start to shutdown!

Problems with the tail appeared in very late July 1942, some 9 months after the first Typhoons were delivered to No 56 Squadron. On July 29th a Typhoon crashed on a familirisation flight, a similar incident occured two weeks later and the wreckage was recovered. The tail unit had completely seperated from the rear fuselage at the transport joint and the elevator mass balance had been snapped off. Initially vibration was the suspected cause, but excessive yaw, elevator flutter and fuselage overstress were also considered.

Mod 286 was introduced in late 1942 to attempt to solve the problem. It involved sighting 12 'fishplates' around the suspect joint. However, accidents continued even with the modifications, averaging about 1 a month up to May 1943, by which time it was decide to fit the Typhoon with the Tempest tail unit and a 4 bladed Rotol prop. Combined with changes to the elevator mass balance and the intertia weight on the control collum these were expected to solve the problems. In addition modifications were made to the engine bolting arrangements. The new mods fixed the problems until March 1944, when 2 Typhoons were lost to structural filures, one of which was during a very heavy RP dive pullout (and may of been from flak) while the second was in a gentle port turn at 27,000 feet. Interestingly, undercarriage failures were observed in subsequent structural mishaps. Gear door dropped in dives on at least two occasions and some Typhoons returned home after gear had dropped on its own!

There were 26 recorded structural failures of Typhoons during and after the war, the last of which occured during August 1945

Kurfurst__
05-01-2005, 02:38 PM
I see LS added his agenda filled posts... lol, Radinger-Otto is 'very inaccurate' etc. Make 109 weaker! Make the 190 weaker ! Boring.

Now back to the subject, keep in mind that in the `30s engineers did not have enough knowladge on structural strenght yet... light metal airframes were knew, even aluminium was a relatively new material. They got the right structural strenght by trial and error, many phenomenons, like behaviour at high Mach numbers was not well understood, experience was gained on the field. Many planes went down until then, few of the major types was an exception. Some had a few accidents, others had a particularly bad record. Now the tail problems of the early 109Fs is known, caused by a factor they could not foresee or calculate yet, engine vibration. The wing issue was a different one, perhaps the new wing of the 109F had some problems, perhaps it was just wear (I got some German docs on how wear effects sustainable G-loads of the airframe, it`s pretty interesting). It could be the pilots exceeded the presribed G-limits imposed on the airframe (usually set at 6-7 Gs at full load, though the actual break limit was closer to 10-12Gs). Balthasar could have easily done that, flying an unarmed 109F at the time he was jumped by enemy planes and he tried to evade them.

Whatever the problem may, there were only a handful of accidents occurring, and not a large serious of such, so Mtt was probably right when it said problems by the sub-contractors or airframe wear. In any case, documents on the 109G-1 subtype I have show they reacted as developers reacted at that time : if something breaks, reinforce it, if it still breaks, reinforce it even more. The 109G type card notes reinforced spars, ribs, and plating, perhaps not only because of those accidents that occured, but because the 109G also carried heavy strores under it`s wings, unlike the 109F. BTW, the 109 dive test that succeeded 850, then to 906 kph TAS in the Radinger/Otto book, was made with a hybrid 109F type, that had the new wings and tail of the 109G.. practically a G-standard a/c, and demonstrates quite well about those 'structural problems' some are so emotional about.

ImpStarDuece
05-02-2005, 12:14 AM
Originally posted by 3.JG51_BigBear:
For what its worth, this is from JG26 Top Guns of the Luftwaffe by Donald Caldwell

A second structural problem did not appear until the aircraft had actually entered combat. Airplanes began returning from missions with ripples in their wing skins, indicative of hidden damage to the wing structure. Apparently neither the factory nor the RLM though the problem was serious, but after the wing spars of several aircraft collapsed in flight, trapping the pilots in their cockpits, Oblt. Schroedter, technical officer of the Third Gruppe, borrowed some straing gauges from Rechlin and ran his own experiments. The weak areas in the wing were identified, and local stiffeners were designed. These could not be applied in the Geshwader shops, however, and Schroedter was given the job of flying obviously damaged aircraft to the repair facility in Antwerp to have their wings replaced.

How would you like to be the TO that had to fly the "obviously damaged aircraft."

Interesting that after 'several' wing failures the RLM and the Messerschmidt factory didn't react quickly. In fact it fell to an offiecr in the field to do something about it. Interesting comment on how the LW felt about its pilots.

For comparison, after the first structural failure on the Typhoon Hawker, the MAP, the A&AEE and the RAF all launched investigations that continued until the close of the war. Granted that the trouble with Typhoons was more persistent but I think it says something about the warring parties.

Aaron_GT
05-02-2005, 09:24 AM
"I was HIGHLY suprised when I learnt that there were just 24 know failures and many of these were attributed to the fact that the Typhoons were often diving above 540 mph."

And the problems were largely fixed anyway.

Aaron_GT
05-02-2005, 09:25 AM
" Airplanes began returning from missions with ripples in their wing skins, indicative of hidden damage to the wing structure."

This could also occur in Spitfires and was attributed to the skin rather than the internal structure.

jugent
05-02-2005, 12:36 PM
Dont make the mistake to think that this game is 100% alike how it was in real life.
Much behavior that would make this game to hard to play is taken away.

For example: The mustang had such a large propeller that the pilot kept the tail to the ground until takeoff otherwise where there a great risk that the prop hit the ground. This prop make a great drag when the engine was at low RPM. A prop A/C without automatic pitchcontrol had a bad glideslope.
Another example; propellertorque is reduced to almost nothing.
When the Hawker tempes and typhoon came the took away a hangar because the planes run into it because of the horrible torque.
And the very good aeronautic engineers of luftwaffe would never have accepted such flight characteristics as the FW Me shows in this game.
After all they constructed the Me-262. The wing design was genious. Only early Migs and SAAB:s understood it. It payed out in Corea.
The weapon-engineers would never have accepted the performance of the MG/Cannons shown in this game.
This game is as it is.

p1ngu666
05-02-2005, 01:06 PM
Originally posted by jugent:
Dont make the mistake to think that this game is 100% alike how it was in real life.
Much behavior that would make this game to hard to play is taken away.

For example: The mustang had such a large propeller that the pilot kept the tail to the ground until takeoff otherwise where there a great risk that the prop hit the ground. This prop make a great drag when the engine was at low RPM. A prop A/C without automatic pitchcontrol had a bad glideslope.
Another example; propellertorque is reduced to almost nothing.
When the Hawker tempes and typhoon came the took away a hangar because the planes run into it because of the horrible torque.
And the very good aeronautic engineers of luftwaffe would never have accepted such flight characteristics as the FW Me shows in this game.
After all they constructed the Me-262. The wing design was genious. Only early Migs and SAAB:s understood it. It payed out in Corea.
The weapon-engineers would never have accepted the performance of the MG/Cannons shown in this game.
This game is as it is.

109 had worse torque problems than typhoon and tempest. the gear was narrow, angle and cambered ment that if u got into a turn, it would carry on or sharpen the turn.

ive heard of one case of typhoon going way ofcourse, guy had put on full trim... in the wrong direction http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

190 would be good, wide track...

p1ngu666
05-02-2005, 01:08 PM
oh and 262 had swept wing, to restore cog and col iirec
like swordfish and il2 and other planes before http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Aaron_GT
05-02-2005, 03:48 PM
oh and 262 had swept wing, to restore cog and col iirec

That's a bit off, as the Germans had been doing high speed research for a few years before using a windtunnel capable of (taking into account Reynold's number) transonic research. The wing sweep was for high speed performance, not COG, and other sweeps for high speed performance were tried including forward sweep (good for bombers as it helps with low speed stability but with some benefit at high speed). Swept wings were also being looked at in the USA, but Germany was ahead of the game at the time. Luckily, with troops rolling to them overland and insufficient alloys for engines it didn't help!