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luftw4ffles
05-06-2004, 10:14 AM
In as few words as possible, "is this accurate?"
The bf109 was regarded as a boom and zoom plane. Currently, the bf109g14 handles the best at high speeds. Why does the g14 handle better than the k4? Why do all bfs turn to concrete at speeds over 500kph? I could understand 650kph+ but 500kph?
Again, "is this accurate?"

"If I had a penny for every online victory, I'd have a lot of pennies."

luftw4ffles
05-06-2004, 10:14 AM
In as few words as possible, "is this accurate?"
The bf109 was regarded as a boom and zoom plane. Currently, the bf109g14 handles the best at high speeds. Why does the g14 handle better than the k4? Why do all bfs turn to concrete at speeds over 500kph? I could understand 650kph+ but 500kph?
Again, "is this accurate?"

"If I had a penny for every online victory, I'd have a lot of pennies."

butch2k
05-06-2004, 10:45 AM
Effect on stick force based on rudder deflection at speed and height on a Bf 109G-5.
400 km/h @ 5500m @ 2.5‚? deflection > 6kg
530 km/h @ 5500m @ 2‚? deflection > 20 kg
610 km/h @ 4000m @ 1.4‚? deflection > 28 kg

[This message was edited by butch2k on Thu May 06 2004 at 10:54 PM.]

Kurfurst__
05-06-2004, 01:47 PM
IAS, or TAS, what are the associated G-forces, butch ?

http://www.x-plane.org/users/isegrim/fat-furred%20tigerB.jpg

"We've got the finest tanks in the world. We just love to see the German Royal Tiger come up on the field".
- Lt. Gen. George S. Patton, Jr. Febuary 1945.

"One day a Tiger Royal got within 150 yards of my tanks and knocked me out. Five of our tanks opened up on him at ranges of 200 to 600 yards and got 5 or 6 hits on the front of the Tiger. They all just glanced off and the Tiger backed off and got away. If we had a tank like that Tiger, we would all be home today."
- Sgt. Clyde D. Brunson, US Army, Tank Commander, February 1945

butch2k
05-06-2004, 02:34 PM
No G-force given it seems, i have to read the whole test protocol and details but the goal was to compare Fw 190 and Bf 109 stick forces. Tailplane is set at +0.75‚?btw
And speed is taken from the speed gauge according to the protocol details.

Abbuzze
05-06-2004, 03:16 PM
Hi Butch2k, do you know the dive test
http://109lair.hobbyvista.com/techref/structures/tails/109.05e43_report/05e43-p1.htm
from http://109lair.hobbyvista.com/index1024.htm

In dives at an angle of 70-80‚? with 906km/h TAS at 5,8km altitude the pilot where not able to pull out of a dive, with Tailplane is set to 1‚?45' he had to use the trimwheel, with the result, that the nose came up so violant that he had to push the stick foreward to be not blacked out.
The tested more and with 1‚?15' it was possible to recover this dive just using the stick (and with the same flightpath so also close to a blackout).

Do you know this dokument and if yes how do you judge it?

I./JG53 PikAs Abbuzze
http://www.jg53-pikas.de/

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couldn‚¬īt restist http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

butch2k
05-06-2004, 03:37 PM
YEs this is a famous document, and i see no reason not to trust it, as far as i remember the events happening in this flight test have been reported in another book about test pilots.
The main problem is what could an over-trained test pilot do compared to a standard pilot. The test pilot usualy have more resistance to blackout because he is used to go to the extreme, he know own to handle dangerous situation, he is not unde rcombat stress etc...

Usualy the max recommanded divespeed was between 750 and 850 TAS (the later being for the K-4). A 5g pullout on a K-4 from a 45‚? dive at 800 kmh required about 400m in height to attain level flight once the pilot pulled the stick. That i think represent what an usual pilot could do in combat w/o too much risk to him and his aircraft. Airframe limit was 6.9 IIRC (from memory), but pilot resistance could be less.

DangerForward
05-06-2004, 07:17 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by butch2k:
No G-force given it seems, i have to read the whole test protocol and details but the goal was to compare Fw 190 and Bf 109 stick forces. Tailplane is set at +0.75‚?btw
And speed is taken from the speed gauge according to the protocol details.<HR></BLOCKQUOTE>

Do you have the numbers for a FW190? Just curious...

DangerForward

BlitzPig_DDT
05-06-2004, 08:43 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by butch2k:
Necessary force for achieving deflection at speed and alt on Bf 109G-5
400 km/h @ 5500m @ 2.5‚? deflection &gt; 6kg
530 km/h @ 5500m @ 2‚? deflection &gt; 20 kg
610 km/h @ 4000m @ 1.4‚? deflection &gt; 28 kg<HR></BLOCKQUOTE>

Would be nice if we had that. We get 20 kilos or more at 400 in AEP.

Luft, I think you should re-think the thread titles. "High speed" isn't the real issue here. It's moderate speeds that they become concrete.

==================================
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Come and spam on our front porch.

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RAF74_Buzzsaw
05-06-2004, 09:45 PM
Salute

According to British tests of the 109E, which had the same joystick and cockpit setup as all the other 109's, it was impossible to exert more than 40lbs force on the stick due the very cramped cockpit. So if you are making your calculations based on the assumption that you can get 50lbs stickforce in a 109, you'd be wrong. The 109 had a very short stick with a short throw. Very little leverage could be obtained.

All other tests of later models of the 109 also showed severe high speed handling problems.

The reason was simple: Turbulence over the wings, bringing on the early onset of compressibility, caused by the aerofoil design and particular the slats. If you check the other major aircraft with slats modelled in IL-2, namely the La-5/La-7 series, you will find they also have very poor high speed handling as well.

To Oleg's credit, ACES EDITION FORGOTTEN BATTLES has started to model the reality of high speed handling, after the inaccuracies of the early FM's of IL-2 and the first version of FB.

SkyChimp
05-06-2004, 09:59 PM
40lbs of lateral force IIRC. But I don't think the forward and backward range of motion was that restricted. And of course, it's the forward and backwards movement that operates the elevators.

Regards,
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RAF74_Buzzsaw
05-06-2004, 10:00 PM
Salute

AFDU tests showed poor elevator response too.

Or are you arguing that the 109 should maneuver at high speed as it did in IL-2 and FORGOTTEN BATTLES?

LeadSpitter_
05-06-2004, 11:00 PM
someone doesnt know the prop stop exploit then over reving http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

http://img14.photobucket.com/albums/v43/leadspitter/newsig.jpg

butch2k
05-06-2004, 11:37 PM
To make it clear the data i'm posting is from actual tests (actually 3 flight made on the same aircraft), it's not calculated data.

Bastables
05-06-2004, 11:50 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by butch2k:
To make it clear the data i'm posting is from actual tests (actually 3 flight made on the same aircraft), it's not calculated data.<HR></BLOCKQUOTE>
Hmmmm Buzzsaws partisan, misguided interpretations versus actual documented tests?..
I think I?ll believe the latter.

lrrp22
05-07-2004, 09:06 AM
Butch,

I'm not sure what to make of the numbers. Were the results considered satisfactory or excessive? How much pitch authority was achieved with 1.4 deg deflection? How did they compare to the 190's numbers? Good or bad?

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by butch2k:
To make it clear the data i'm posting is from actual tests (actually 3 flight made on the same aircraft), it's not calculated data.<HR></BLOCKQUOTE>

Kurfurst__
05-07-2004, 11:02 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by butch2k:

Usualy the max recommanded divespeed was between 750 and 850 TAS (the later being for the K-4). A 5g pullout on a K-4 from a 45‚? dive at 800 kmh required about 400m in height to attain level flight once the pilot pulled the stick. That i think represent what an usual pilot could do in combat w/o too much risk to him and his aircraft. Airframe limit was 6.9 IIRC (from memory), but pilot resistance could be less.<HR></BLOCKQUOTE>

Interesting, why is the higher limit for the 109K - I suppose it has to do with less external stuff like tailwhell and cleaner lines...? Did dive limits increased with the 109K, AFAIK they state the same 750 kph as with other versions in the manual...Interesting data BTW about dive recoveries.. Could you post this one?

Re, 109K elevator authority, according to turning ability docs for 109K, it is stated that at 180 m/sec = 648km/h TAS @ 6000m altitude, a complete 360 degree, 5G turn can be completed in 24 secs, and required a turn radius of 550m while maintaining alitude at a 78.5 degree bank using maximum power output. Rather good, IIRC it`s even better than La-7 at 5000m. So the 'concrete elavotor' story is rather overstated.

http://www.x-plane.org/users/isegrim/fat-furred%20tigerB.jpg

"We've got the finest tanks in the world. We just love to see the German Royal Tiger come up on the field".
- Lt. Gen. George S. Patton, Jr. Febuary 1945.

"One day a Tiger Royal got within 150 yards of my tanks and knocked me out. Five of our tanks opened up on him at ranges of 200 to 600 yards and got 5 or 6 hits on the front of the Tiger. They all just glanced off and the Tiger backed off and got away. If we had a tank like that Tiger, we would all be home today."
- Sgt. Clyde D. Brunson, US Army, Tank Commander, February 1945

butch2k
05-07-2004, 12:37 PM
Yes isegrim i know those documents.
The K-4 airframe was most probably re-inforced compared to the Gustav series indeed the K-4 could load a 500kg bombs while the G-10 couldn't even if equipped with an ETC503.

From a K-4 manual :
http://mapage.noos.fr/~olefebvre/109k4-limits.jpg

JG5_UnKle
05-07-2004, 12:54 PM
Just a bump - I'm still interested in this one after many threads http://ubbxforums.ubi.com/images/smiley/16x16_smiley-happy.gif

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Public Forum (http://www.alucinor.com/eismeer/forum)

Magister__Ludi
05-07-2004, 05:39 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by RAF74BuzzsawXO:
Salute

AFDU tests showed poor elevator response too.

Or are you arguing that the 109 should maneuver at high speed as it did in IL-2 and FORGOTTEN BATTLES?<HR></BLOCKQUOTE>

Late Bf-109s together with Fw-190s and Mustangs should have the best high speed maneuvrability of all planes, because they were designed for this speed regime. All others fighters had lighter controls at slower speeds, including cruising, this is why the 3 fighters mentioned above got the bad reputation of having heavy controls, since they had heavier controls in most regimes except high speed fighting (of course Fw-190 had exceptionally light ailerons at any speed).

In order to get something meaningful regarding the heaviness of controls we need data the way NACA tested the maneuvrability of American fighters: number of pounds force per G at a given speed. This can be easily be converted in turn rate. The numbers Butch posted cannot be used in any comparison unfortunatelly. 30 kg at 600km/h or 20 kg at 500km/h does not say anything. Which one gave better turn rate? From this values you cannot even compare the turn rate at different speeds for the very same plane.

NACA measured a 40kg stick force per G at 400mph for P-39 (this is from memory, I will check at home), this means that at this speed you cannot blackout no matter how hard you try to pull the stick, in fact you could barely turn (or pull out of dive). On the other hand at slightly higher speed a Bf-109 in proper trim would start a violent 6G pull-out without even touching the stick. This is of course not modelled in FB, and from the way things are going this sim there is little chance for realistic historical performance.

Magister__Ludi
05-07-2004, 05:46 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Kurfurst__:
[QUOTE]Originally posted by butch2k:

Re, 109K elevator authority, according to turning ability docs for 109K, it is stated that at 180 m/sec = 648km/h TAS @ 6000m altitude, a complete 360 degree, 5G turn can be completed in 24 secs, and required a turn radius of 550m while maintaining alitude at a 78.5 degree bank using maximum power output. Rather good, IIRC it`s even better than La-7 at 5000m. So the 'concrete elavotor' story is rather overstated.

<HR></BLOCKQUOTE>


According to Russian tests La-7 could complete a 360 deg turn in 30 sec at 5000m and 320 IAS. This means that K4 was much better in turn at least at this altitude. I did not try it, but I'll test to see if I can outturn La7 in a flat horizontal turn fight at 5000m. Though I'm pretty much certain what will be the result. I'll post the track.

DangerForward
05-07-2004, 06:17 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Magister__Ludi:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Kurfurst__:
[QUOTE]Originally posted by butch2k:

Re, 109K elevator authority, according to turning ability docs for 109K, it is stated that at 180 m/sec = 648km/h TAS @ 6000m altitude, a complete 360 degree, 5G turn can be completed in 24 secs, and required a turn radius of 550m while maintaining alitude at a 78.5 degree bank using maximum power output. Rather good, IIRC it`s even better than La-7 at 5000m. So the 'concrete elavotor' story is rather overstated.

<HR></BLOCKQUOTE>


According to Russian tests La-7 could complete a 360 deg turn in 30 sec at 5000m and 320 IAS. This means that K4 was much better in turn at least at this altitude. I did not try it, but I'll test to see if I can outturn La7 in a flat horizontal turn fight at 5000m. Though I'm pretty much certain what will be the result. I'll post the track.<HR></BLOCKQUOTE>

Where did you find the 30 second turn test? I'm always looking for more hard flight results.

DangerForward

Kurfurst__
05-08-2004, 04:27 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by butch2k:
Yes isegrim i know those documents.
The K-4 airframe was most probably re-inforced compared to the Gustav series indeed the K-4 could load a 500kg bombs while the G-10 couldn't even if equipped with an ETC503.<HR></BLOCKQUOTE>

Yep, it`s seems likely, especially with these dive limits in mind, ie. the fact they give the same limits even with considerable external load like Gondolas. I suppose the wings must have been reinforced in addition to the fusalage, too.., as per going from Friedrich to Gustav. I guess they choosed to do that since they were building new airframes anyway, it wasn`t problematic for production. Until now I was more inclined to believe the 500kg was allowed for K-4 only because long tailwheel were standard with them, G-10s were more mixed bunch (ie. ground clearance issues). IIRC also the u/c legs were reinforced, too...

As per the dive limits for the K, I suppose these are TAS? It`s a bit edgy, they only state it`s from the speed gauge, but corrected for altitude. Now, another guess, the Me 262 had such a speed gauge with dual arms IIRC, and the 109K`s cocpit panel ALSO took parts from the 262 cocpit... coincidence, or they used the same/similiar speed gauge?

BTW, I am not sure if you haven`t got that one, but I received a May44 605L development paper, and it basically states that a, it seems from text L-type supercharger is to be able to be fit on D engine b, states also 605L would fit into 109K (Db605D) cowling w/o modifications, engine bearer can be the same etc. Kinda fuel for thought, isn`t it? http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

http://www.x-plane.org/users/isegrim/fat-furred%20tigerB.jpg

"We've got the finest tanks in the world. We just love to see the German Royal Tiger come up on the field".
- Lt. Gen. George S. Patton, Jr. Febuary 1945.

"One day a Tiger Royal got within 150 yards of my tanks and knocked me out. Five of our tanks opened up on him at ranges of 200 to 600 yards and got 5 or 6 hits on the front of the Tiger. They all just glanced off and the Tiger backed off and got away. If we had a tank like that Tiger, we would all be home today."
- Sgt. Clyde D. Brunson, US Army, Tank Commander, February 1945

Marc-David
05-08-2004, 06:01 AM
Hi all,

this is a very informative thread, and the dive-test-links are very good.

One Observation to distinguish between test&real combat situation: The test plane was equiped with a sort of ejection-seat "Katapultsitz", wich might have greatly reduced the test-pilot's fear while diving. (And surly the testplane was in excellent condition, even with the new tail)

But all in all it shows, that a (real) test-Me109 G is able to pull out from a dive around 800km/h TAS, when the tim is set to +1''15'. Under frontline conditions it might be only 700-750 km/h TAS.

So: How many trimclicks is this in FB:AEP? Or how long must I press my trimknob? Could these tests be reproduced in a QMB-mission on Crimeamap starting @10000m? I think, Ill give it a try during the weekend....

Yours, Marc-David

05-08-2004, 10:47 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Magister__Ludi:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Kurfurst__:

Re, 109K elevator authority, according to turning ability docs for 109K, it is stated that at 180 m/sec = 648km/h TAS @ 6000m altitude, a complete 360 degree, 5G turn can be completed in 24 secs, and required a turn radius of 550m while maintaining alitude at a 78.5 degree bank using maximum power output. Rather good, IIRC it`s even better than La-7 at 5000m. So the 'concrete elavotor' story is rather overstated.
<HR></BLOCKQUOTE>


According to Russian tests La-7 could complete a 360 deg turn in 30 sec at 5000m and 320 IAS. This means that K4 was much better in turn at least at this altitude. <HR></BLOCKQUOTE>

This data cannot be compared because 30 sec at 5000 meters for La-7 is sustained turn time, and 24 seconds at 6000 meters for Bf.109K-4 - turn with loss of airspeed.

butch2k
05-08-2004, 11:22 AM
Isegrim, it's the same gauge as in the 262.

Kurfurst__
05-09-2004, 07:42 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by butch2k:
Isegrim, it's the same gauge as in the 262.<HR></BLOCKQUOTE>

Thanks... Not in Il-2 it seems.... K-4 has the same gauge as all the rest of the 109s http://ubbxforums.ubi.com/infopop/emoticons/icon_frown.gif

Was the the whole panel with the instruments, VSI indicator (+ 0-50 m/sec) etc the very same? I think Oleg should change it then some time in the future for the K...

All the Bf 109s would basically need a complete rework of 3D model, and higher quality textures in the cocpit model, ie. the VSI of the K-4 is next to useless, it`s so bad quality textures. And those inaccuracies, aligment the MG131s, baggage compartment doors, the bad model of the Erla Haube with remaisn of the 3-piece canopy on the top struts. BAH! http://ubbxforums.ubi.com/infopop/emoticons/icon_frown.gif

http://www.x-plane.org/users/isegrim/fat-furred%20tigerB.jpg

"We've got the finest tanks in the world. We just love to see the German Royal Tiger come up on the field".
- Lt. Gen. George S. Patton, Jr. Febuary 1945.

"One day a Tiger Royal got within 150 yards of my tanks and knocked me out. Five of our tanks opened up on him at ranges of 200 to 600 yards and got 5 or 6 hits on the front of the Tiger. They all just glanced off and the Tiger backed off and got away. If we had a tank like that Tiger, we would all be home today."
- Sgt. Clyde D. Brunson, US Army, Tank Commander, February 1945