Flutter...

Should we be able to observe fluttering at higher ( 750km/h + ) speeds ?

I can dive past that speed in the K-4, and the stick forces ( and rudder too ) increase considerably, and, at limiting speeds I start "losing parts", but there is never an hint of flutter, the stick never shakes either ?

Finnish pilots at least described flutter not to happen up until very high speeds. Here are two examples. I guess the rotating part of the second Interview is well modeled, since you cant compensate roll in very high speed dives with ailerons/rudder anymore.

Me 109 G:

"-Someone asked of the top speed of the Me. Mr Väinö Pokela told earlier it's 720 km/h, when I interviewed him.

Normally we flew the Me at 500 km/h, but at a tough spot we could go some 600 km/h. But the absolute speed limit is found in dive. I had to do some over 900 km/h dives. The speedometer scale ends at 900, and at that you feel the flutter effect in the wings. Guess it was very near the top speed, when the plane felt like falling apart."

- Edvald Estama, Finnish fighter pilot. Source: Recollections by Eino and Edvald Estama by Finnish Virtual Pilots Association.

Me 109 G:

"The maximum speed not to be exceeded was 750kmh. Once I was flying above Helsinki as I received a report of Russkies in the South. There was a big Cumulus cloud on my way there but I decided to fly right through. I centered the controls and then something extraordinary happened. I must have involuntarily entered into half-roll and dive. The planes had individual handling characteristics; even though I held the turning indicator in the middle, the plane kept going faster and faster, I pulled the stick, yet the plane went into an ever steeper dive.

In the same time she started rotating, and I came out of the cloud with less than one kilometer of altitude. I started pulling the stick, nothing happened, I checked the speed, it was about 850kmh. I tried to recover the plane but the stick was as if locked and nothing happened. I broke into a sweat of agony: now I am going into the sea and cannot help it. I pulled with both hands, groaning and by and by she started recovering, she recovered more, I pulled and pulled, but the surface of the sea approached, I thought I was going to crash. I kept pulling until I saw that I had survived. The distance between me and the sea may have been five meters. I pulled up and found myself on the coast of Estonia.

If I in that situation had used the vertical trim the wings would have been broken off. A minimal trim movement has a strong effect on wings when the speed limit has been exceded. I had 100kmh overspeed! It was out of all limits.

The Messerschmitt's wings were fastened with two bolts. When I saw the construction I had thought that they are strong enough but in this case I was thinking, when are they going to break

- What about the phenomenon called "buffeting" or vibration, was there any?

No, I did not encounter it even in the 850kmh speed."

- Kyösti Karhila, Finnish fighter ace. 32 victories. Source: Interview by Finnish Virtual Pilots Association.

Very interesting read rel4y!

Thx for sharing!

Which, BTW, and together with what I've been reading, contributes even more to raise the level of accuracy reached by our K-4 in DCS !

I think it is great that we keep seeking more and more realism in the modules. I love the knowledge that's out there too.

You can learn an awful lot just reading through some of the more enlightened posts here. :thumbup:

I think it is great that we keep seeking more and more realism in the modules. I love the knowledge that's out there too.

 

You can learn an awful lot just reading through some of the more enlightened posts here. :thumbup:

I totally agree with you Neil (like usual), lots of enlightened and enlightening posts here. Just a shame that to get to them I have to wade past the few unenlightened posts that then occupy my very limited brain capacity....

I cannot imagine how fast his heart must have been beating with the sea coming up at 850 km/h, very lucky to be able to tell his tale.

Just one thing... The109 speedometer scale ends at 750kph... And one of those pilots said it ends at 900kph. Was there a 109 series that had different speedometer type? Or is it custom Finish one? Or just a memory of an old man playing tricks on him?

Just one thing... The109 speedometer scale ends at 750kph... And one of those pilots said it ends at 900kph. Was there a 109 series that had different speedometer type? Or is it custom Finish one? Or just a memory of an old man playing tricks on him?

There is an inner circle going beyond the 750 mark which indicated up to 900 km/h. It was used from G2 (G1) onwards, maybe not exclusively. The F4 still had the old type.

Interesting thread!...so these pilot reports, does DCS take any into consideration/use when trying to make these aircraft as RL

Hey I should try this. Go down in a negative G.

At least in the latest versions of the K-4, which is after all still in beta, the control stiffening with dynamic pressure has been modeled in what I believe to be a very plausible "replica" of the real thing.

We get rudder, aileron and elevator forces that create big problems if we get up to 700+ km/h, and even less, in agreement with pretty much everything I read IRL.

Salute to all!

In His Book Die Erste und die Lezte , Adolf Galand told about a escape He did in his Me 109(wich modell I dont know) purssued by Mustang´s He entered in a dive were he closes his radiators and reached 900kph smelling the glycol boiling and with some rivets flying of the wing skin, and also in dispair He fires his guns with the smoke of them living behind wehn the Mustang´s finally living His tale!

Martim!