Messerschmitt Me 309/509 Projects & Prototypes

[blackkite]

By the way - is the "Me 509" a real project or a postwar fake?

If only we have the original drawing of 509........

 

[hesham]

By the way - is the "Me 509" a real project or a postwar fake?

What ?.

 

[Grzesio]

A single wartime drawing, document, whatever...
I've just encountered information, the 509 was given birth in the 1970s by a certain book author angry that another authors just copied information from books or articles, without any archive research. And so his freshly invented story on the 509 was quickly multiplied in other publications...

 

[newsdeskdan]

A single wartime drawing, document, whatever...
I've just encountered information, the 509 was given birth in the 1970s by a certain book author angry that another authors just copied information from books or articles, without any archive research. And so his freshly invented story on the 509 was quickly multiplied in other publications...

There was definitely an Me 409 (what would become the Me 155) and an Me 609 (test-ready Me 262) but I've never seen a single mention of an Me 509 anywhere in period documents. It's not impossible that it briefly existed but it seems doubtful.

 

[blackkite]

I imagine that German engineers thought that which is better P-39 and P-51?

 

[Raa]

Re: Messerschmitt Me 309 versions

A very interesting article about the Messerschmitt Me 309 is published in the August 2017 issue of the German magazine Klassiker der Luftfahrt. IMHO some unseen new pictures of the the flight tests are featured in this article.
You can also buy and download the article at their website.
Link: http://www.klassiker-der-luftfahrt....tt-me-309-die-letzte-09/734200/paidattachment

I can't find that magazine. I am very curious, could you please give me some more details?

 

[Vahe Demirjian]

Re: Messerschmitt Me 309 versions

A very interesting article about the Messerschmitt Me 309 is published in the August 2017 issue of the German magazine Klassiker der Luftfahrt. IMHO some unseen new pictures of the the flight tests are featured in this article.
You can also buy and download the article at their website.
Link: http://www.klassiker-der-luftfahrt....tt-me-309-die-letzte-09/734200/paidattachment

I can't find that magazine. I am very curious, could you please give me some more details?

The magazine containing the Me 309 article you mention appears at this link:

Klassiker der Luftfahrt

www.flugrevue.de

 

[Raa]

Re: Messerschmitt Me 309 versions

A very interesting article about the Messerschmitt Me 309 is published in the August 2017 issue of the German magazine Klassiker der Luftfahrt. IMHO some unseen new pictures of the the flight tests are featured in this article.
You can also buy and download the article at their website.
Link: http://www.klassiker-der-luftfahrt....tt-me-309-die-letzte-09/734200/paidattachment

I can't find that magazine. I am very curious, could you please give me some more details?

The magazine containing the Me 309 article you mention appears at this link:

Klassiker der Luftfahrt

www.flugrevue.de

Thank you.

By the way, I don't know if there is a demand for it, but I think I'll compile the currently confirmed photos of Me 309 V1 here.

 

[Raa]

and Me 309 V2

Me 309 was also created V3 and V4, but unfortunately no photos of these two aircraft have been found. Of these, the V3 was considered for export to the Japanese ally.

 

[riggerrob]

Dear Raa,

So both GE+CU and GE+CV crashed?

re. photo Scan 2022-01-22-120105.jpg
Are those external balance weights bolted to the propeller blade hubs?

 

[Foo Fighter]

Were these aircraft flown by the allies post war?

 

[Raa]

So both GE+CU and GE+CV crashed?

Yes.
GE+CU (Me 309 V1) was repaired after the accident.
However, GE+CV (Me 309 V2) made its first flight with Karl Baur at the controls, but had an accident on landing, and ended up like the one in the photo. Mischievous Karl
After that, the Me 309 V2 was not repaired and probably scrapped.

Are those external balance weights bolted to the propeller blade hubs?

In the photo, the top propeller looks like that, but I'm not sure about the bottom two propellers.

Edit:
If you look closely again, you will see that the balance weight in the front does indeed appear to be attached with bolts. You can't see the base of the balance weight at the back, but it is probably bolted on as well.

Were these aircraft flown by the allies post war?

Nope.

Me 309 V1 (GE+CU) was abandoned in the field after it was rejected in 1943. It was later found by the US Army, but was probably scrapped. The third photo in my post #48 is the Me 309 V1 taken by the US Army.
Me 309 V2 (GE+CV) was not repaired and probably scrapped after it had an accident on its first flight.
Me 309 V3 (GE+CW) was destined for export. This aircraft was purchased by Lieutenant General Osamu Ohtani, a Japanese resident military officer who was interested in German technology at the time. He purchased the Me 309 V3 and a set of drawings for 1.2 million Reichsmark.
However, the Me 309 V3 was destroyed in a night bombing run that lasted from February 25 to 26, 1944.
Me 309 V4 (GE+CX) was also destroyed in an air raid.

As you can see, all of the prototype Me 309s were either scrapped or destroyed in air raids, and unfortunately were never flown by the Allies.

 

[Foo Fighter]

Thanks very much, appreciated.

 

[Raa]

I'll also post pictures of the Bf 109 V23, which were used as experimental aircraft for landing gear before the Me 309 prototype was built

 

[Raa]

And here is a picture of a Bf 109 V31 used to test the retractable radiator.

 

[hesham]

From Fly Past 1987/10,

the Messerschmitt Me.609.

 

[blackkite]

Hi!

View: https://www.youtube.com/watch?v=Roit4Odw3UY

 

[blackkite]

Hi!

Messerschmitt Me-309, Fighter

https://www.secretprojects.co.uk/attachments/94323942-s-jpg.672600/

https://www.secretprojects.co.uk/attachments/me309-v4-jpg.548053/

　↑　Nose gear cover is complicated and retractable radiator is impressive.

 

[blackkite]

Classic Resin 1/48 Me-309 by Scott Van Aken

 

[Luftwaffles]

I hope this is the right place for this, if not, please feel free to move it elsewhere.

The question about the Me 309 wing profile in the book-review thread piqued my curiosity.
https://www.secretprojects.co.uk/th...itics-by-dan-sharp-and-calum-e-douglas.41814/

So I put together a small comparison done in XFOIL (viscous mode). The data for the unmodified NACA 15014 are taken from Airfoiltools.com, just as the wing profiles of the P-51 D and H.

The modifications done to NACA 15014 in order to match the Me 309 airfoil designation which can be found in Dan's book, were done by me in XFOIL, I hope they are accurate. At least they look right. Thanks to Sienar for linking to the explanatory thead for reading german modifications to NACA profiles. Please also note the wonky quality of the P-51 D profile and pressure distribution resulting from the available profile-dataset.

For the comparison I chose Ma 0.5 since I wanted to steer clear of any transonic effects while being relevant to the speeds these planes flew at. Different Reynolds numbers are included, you might want to discard the Re 1,5000,000 results, since there seems to have been faulty user input causing some of them to run at 15,000,000 instead. I also limited the angle of attack range to maximum 6° since I wanted to avoid any separation issues.

The laminar to turbulent transition in these simulations was apparently triggered by a separation bubble (visible as a plateau in the total pressure distribution). Higher Reynolds numbers make this effect slowly disappear (as it should) so I feel relatively confident in the chosen Reynolds number range w.r.t. its capability to show the effect which I wanted to see.

What can you take from this?
The transition from laminar to turbulent flow indeed happens later for the Me 309 profile (so the modified NACA15014-0.825-37) compared to the unmodified NACA15014 (Re 1,000,000, AoA 0°, estimated 68% axial chord end of suction side transition bubble NACA15014-0.825-37 vs 51% axial chord end of suction side transition bubble NACA15014) . However, the P-51 H profile shows this only at roughly 76% axial chord. The P-51 D profile shows this phenomenon at 52% chord but since the surface is so wobbly this is most certainly not accurate and artificially shifted towards the leading edge.

Now can the NACA15014-0.825-37 be considered a laminar flow profile? Yes and no, I would say. It is more of a laminar flow profile than a typical NACA15014. But it does not reach the laminar flow lengths of the P-51 H profile. This is aggravated by the fact, that the Me 309 profile has a lower cl compared to the P-51 H Mustang profile at the same angle of attack and thus needs a higher AoA to generate the same lift as the latter profile. This in turn causes a forward shift in the transition point and shifts the scales even further in favor of the P-51 H profile. Just look at the large advantage in L/D the H Mustang profile has!

The attached document contains the plots on which I based my conclusions, please let me know if you think there is an error.

 

[wasp850]

A practical question : Would this wing give the Me 309 an advantage over other aircraft ?

 

[Foo Fighter]

At first glance, something which should/could be read as a whodunnit crime story.

 

[Luftwaffles]

A practical question : Would this wing give the Me 309 an advantage over other aircraft ?

I think this is a tough question to answer. The performance of the overall wing is certainly dependent on the profile for these aircraft, however it is also heavily influenced by the other wing design parameters, such as overall wing area, taper, aspect ratio, twist (geometric and aerodynamic), dihedral, wing tip design etc.
We would need to see the distribution of lift for the Me 309 wing to get an indication of the wing's performance and that requires a different set of simulations.

With these caveats out of the way, to me, the Me 309 profile alone indicates this:

1. It does not have a high cl, so it does not generate a lot of lift at low speeds
Discarding the other parameters, this indicates that we need a well designed flap system for takeoff and landing as well as low speed climb.
Contrast this with the Clark-YH profile of the Hurricane (as stand in for an older, very popular airfoil).
A much thicker profile with higher cl, so we can expect the lift provided at low speeds to be higher. This (again discarding all other influence factors) enables lower takeoff and landing speeds, as well as higher rate of climb at low speeds. This will also aid with low speed turning to a certain extent.

2. The Me 309 profile seems a bit more sensitive towards high AoA separation (compared to Clark-YH). This can indicate a lmitation in instantaneous turn rate compared to airfoils with a rounder leading edge. It might also necessitate the presence of slats for high AoA situations such as maneuvers or (to a certain extent) landing. And indeed the Me 309 was designed with slats.

3. However, and I suspect this to be the key design driver, at moderate AoA (I did a rough comparison at 2°) the lift over drag is significantly higher than for the Clark-YH. This indicates less profile drag and thus enables reaching higher speeds or attaining a longer cruising range. This effect is of course more pronounced for the P-51 H profile, which we know to have an even better range and higher max. speed compared to the 309. The critical Mach-number of the Me 309 profile is also lower than for the Mustang H profile (see the higher cp-max in my plots), so in a high speed dive, the wing might become a limitation at lower speeds compared to the P-51 H (assuming transonic drag rise from other regions of the aircraft does not prohibit reaching these speeds).

Putting everything in a nutshell: it might offer an advantage for high speed and cruise over some aircraft but has downsides that need to be mitigated via aides such as slats at lower speeds. Considering the fact, that the 109 already needed all of these aides anyways, I would dare say the Me 309 profile is designed well enough to not be considered a downside of the aircraft.

 

[sgeorges4]

Hello, do we have any original drawing showing the weapon configuration? I ask because I'mm not too sure how to do my RS model wing guns.

Thanks for your answers!

 

[wasp850]

I think this is a tough question to answer. The performance of the overall wing is certainly dependent on the profile for these aircraft, however it is also heavily influenced by the other wing design parameters, such as overall wing area, taper, aspect ratio, twist (geometric and aerodynamic), dihedral, wing tip design etc.
We would need to see the distribution of lift for the Me 309 wing to get an indication of the wing's performance and that requires a different set of simulations.

With these caveats out of the way, to me, the Me 309 profile alone indicates this:

1. It does not have a high cl, so it does not generate a lot of lift at low speeds
Discarding the other parameters, this indicates that we need a well designed flap system for takeoff and landing as well as low speed climb.
Contrast this with the Clark-YH profile of the Hurricane (as stand in for an older, very popular airfoil).
A much thicker profile with higher cl, so we can expect the lift provided at low speeds to be higher. This (again discarding all other influence factors) enables lower takeoff and landing speeds, as well as higher rate of climb at low speeds. This will also aid with low speed turning to a certain extent.

2. The Me 309 profile seems a bit more sensitive towards high AoA separation (compared to Clark-YH). This can indicate a lmitation in instantaneous turn rate compared to airfoils with a rounder leading edge. It might also necessitate the presence of slats for high AoA situations such as maneuvers or (to a certain extent) landing. And indeed the Me 309 was designed with slats.

3. However, and I suspect this to be the key design driver, at moderate AoA (I did a rough comparison at 2°) the lift over drag is significantly higher than for the Clark-YH. This indicates less profile drag and thus enables reaching higher speeds or attaining a longer cruising range. This effect is of course more pronounced for the P-51 H profile, which we know to have an even better range and higher max. speed compared to the 309. The critical Mach-number of the Me 309 profile is also lower than for the Mustang H profile (see the higher cp-max in my plots), so in a high speed dive, the wing might become a limitation at lower speeds compared to the P-51 H (assuming transonic drag rise from other regions of the aircraft does not prohibit reaching these speeds).

Putting everything in a nutshell: it might offer an advantage for high speed and cruise over some aircraft but has downsides that need to be mitigated via aides such as slats at lower speeds. Considering the fact, that the 109 already needed all of these aides anyways, I would dare say the Me 309 profile is designed well enough to not be considered a downside of the aircraft.

Just a question, why are you using the Mustang H profile ?

 

[Luftwaffles]

Because, as a NACA 6-series profile, it is an example of a very well designed and (at the time) modern profile. It is also often used as the posterchild of practical laminar flow profiles, since it worked so well. So in a way, this profile represents the gold standard of its time.

 

[wasp850]

Because, as a NACA 6-series profile, it is an example of a very well designed and (at the time) modern profile. It is also often used as the posterchild of practical laminar flow profiles, since it worked so well. So in a way, this profile represents the gold standard of its time.

I understand correctly that the Me 309 wing profile was "more laminar" than the P-51D profile ? I know I'm simplifying greatly, but purely from a wing profile perspective would that be the case ?

 

[PabloSniper]

It would have been interesting to have had a fighter with the DB-603