Pilot G-limit compared to the Bf 109 and Fw 190

Hello there!

I found that the blackout limit (where the pilot starts to black out) is around 5 Gs for the P-51D, 6.5 for the Bf 109 and 7+ for the Fw 190.

I find this to be a bit unfair... If anything, they should be at the same level, considering they're still humans in the cockpit. Any probable reason as to this, or is it just overlooked?

The pilot sits lower in the Bf 109 with his legs more straight. This helps with higher G forces.

Don't know about the Fw 190, but the pilot sits more upright in the P51D.

Okay, but would it make a difference as big as 1.5 G?

Okay, but would it make a difference as big as 1.5 G?

Yep.

What about the Fw 190? Should you really be able to pull over 7Gs and not black out? It seems unreal.

The pilot sits lower in the Bf 109 with his legs more straight. This helps with higher G forces.

Don't know about the Fw 190, but the pilot sits more upright in the P51D.

I think the FW-190 pilot positioning is slightly better for handling acceleration than the Bf-109.

IIRC, a long pilot physiology discussion was held a while back. Yo-Yo related the model in DCS is the same basic principle used in acceleration tolerance research.

They calculate the pressure in a column of blood. When the pressure drops below a threshold, the brain does get oxygen and your pilot vision is effected.

The more the column is offset from the z-axis, the higher the G- tolerance. IIRC, the G suit pants of the USAAF are also modeled. Probably as a fixed amount of pressure modified by the angle of the legs to the z-axis, which is exactly what G-suits do.

What about the Fw 190? Should you really be able to pull over 7Gs and not black out? It seems unreal.

http://goflightmedicine.com/wp-content/uploads/2014/06/G-Tolerance1.jpg

The seat angle makes a huge difference in the G-tolerance of the pilot.

For example, the 30 degree incline of the F-16 allowed to have the edge over its competitors during trials and later service. Interestingly enough, that angle also led it to giving its pilots more neck injuries than other aircraft.

The trade off with seat angle is reduced rear quarter visibility and a sore neck!!

At least the USAAF has a G -suit.

Think of the Spitfire.....

Upright seating and NO G-protection at all for the pilot. :(

http://aerosociety.com/Assets/Docs/Publications/The%20Journal%20of%20Aeronautical%20History/2014-01_Rood_Aircrew_clothing.pdf

In P-51 Mustang vs Fw-190 on page 14 it states that VIII Fighter Command was using anti-g suits in P-51's starting just before D-Day.

Maybe there should be an option, with or without.

Crump... There is no way in the world that on average, P-51/47 pilot from 1944 is going to be less resistant to G forces than Bf109 or 190 pilot.

A quote about G suit used in the Mustang

" An air pressure outlet connection on the left side of the pilot's seat provides for attachment of the air pressure intake tube of the anti-G suit. Air pressure for the inflation of the anti G-suit bladders is supplied from the exhaust side of the engine-driven vacuum pump and is regulated by a Type M-2 valve, which also regulates pressure to the drop tanks. If drop tanks are installed on the airplane, the acceleration force (G-load) required to actuate the M-2 valve should be approximately 3 to 3.5 G because of the approximately 5 psi pressure exerted in the tanks. If drop tanks are not installed, the valve should open at 2 G. After the valve opens, pressure is passed through a regulator valve into the suit in proportion to the G-force imposed. For every 1 G acceleration force, a corresponding one psi pressure is exerted in the anti-G suit" Mustang Flight Handbook.

Spitfire pilots would use Franks Flying Suit Mark II,which was developed 1940, equiped later on.

https://books.google.pl/books?id=_6hymYAgC6MC&pg=PA94&lpg=PA94&dq=anti-g+suit+ww2&source=bl&ots=Nx3aRWFHYw&sig=DKOfF6_TYqq4NRoDh1TH4XzO9CQ&hl=pl&sa=X&ved=0CGAQ6AEwC2oVChMIoqum7ZaPyAIVAf1yCh32kwNr#v=onepage&q=anti-g%20suit%20ww2&f=false

States:

"A conventional anti G-Suit increases ROR and GOR tolerances by approximately 1 to 1.5G."

So, if an average person is capable of taking 4.5G, a trained fighter pilot can take 5G. That is giving 5.5/6G and 6/6.5G respectively.

109 cockpit is at an angle, but I've read a while ago that just over 5G was the max that the pilot could take. That would probably mean in aproximation that 5.5G for the fit pilot and 5.0 for an averge person giving 0.5G increase.

You have also remember that in 109 you are at speeds that high G occures you have to constantly fight with the stick and rudder because controls are very heavy. Now imagine pulling on that stick in that small cramped cockpit with both hands with all your might while G forces press you hard. Its just impossible that the 109 pilot would, from default, have a single advantage in that case.

5.0G pilot+3.0 from the modern suit + 1.0 or 1.5 from the F16 seat at 30deg=9.0+G possible if pilot can keep his breathing techniques.

In P-51 Mustang vs Fw-190 on page 14 it states that VIII Fighter Command was using anti-g suits in P-51's starting just before D-Day.

 

Maybe there should be an option, with or without.

It would be a good option, but I don't see need for it realy. As our fighting is not going to take place before November 1944 and thats 6 months after D-Day.

We have Fw190D9 and Bf109K4 which are both from around November or late November/December time period.

There is no way that both those planes were flying before D-Day(June 1944). If Germans get older planes, I am ok with limiting US pilots to flight without G suit, but for now it seems pointless to develop such option to a plane that won't fight in such environment.

The FW190's pilot seat doesn't look that angled to me:

And here's the P51D's pilot's seat, and it's adjustable:

Judging from the position on the ilustration the P-51's seat seems to match the 5.5G ilustration if not beeing a bit more angled. If we add anti G suit we get up to 7G of resistance, just at the actual needed G force for Max P-51D performance as the plane was rated for 7G with standard combat load.

And here's the P51D's pilot's seat, and it's adjustable:

which makes perfect sense if using a back-pack parachute.

At least the USAAF has a G -suit.

 

Think of the Spitfire.....

 

Upright seating and NO G-protection at all for the pilot.

I'm gonna start a petition for Bader-isation of all Fighter Command pilots to try and compensate for this design shortcoming of the human body!

It will be a simple field modification to the pilot. Chloroform and a hacksaw is all thats needed.

I actually love the idea of realistically different G limits for different aircraft. It adds another dynamic to combat.

which makes perfect sense if using a back-pack parachute.

Parachute in on your bum, not the back.

I'm gonna start a petition for Bader-isation of all Fighter Command pilots to try and compensate for this design shortcoming of the human body!

 

It will be a simple field modification to the pilot. Chloroform and a hacksaw is all thats needed.

 

I actually love the idea of realistically different G limits for different aircraft. It adds another dynamic to combat.

But Brits used Franks Flying Suit Mark II which is also a G-Suit present since 1940.

At least the USAAF has a G -suit.

 

Think of the Spitfire.....

 

Upright seating and NO G-protection at all for the pilot. :(

 

http://aerosociety.com/Assets/Docs/Publications/The%20Journal%20of%20Aeronautical%20History/2014-01_Rood_Aircrew_clothing.pdf

I thought the Spitfire rudder pedal design had a second set of higher bars above the standard bars for the feet. This raised the legs more when in combat to give better tolerance to G-forces.

Talisman

From reading the extract below, from this link, It would appear to be fair to model the G-suit for the Seafire. This G-suit apparently increased resistance up to plus 3g over what could normally be sustained.

http://aerosociety.com/Assets/Docs/Publications/The%20Journal%20of%20Aeronautical%20History/2014-01_Rood_Aircrew_clothing.pdf

In mid-1940 the RAF agreed to supply a Spitfire to Canada for further flight trials and in early 1941 Franks came to Britain to demonstrate and develop his suit. Considerable development took place and once experimental flight reports had been completed, two operational squadrons carried out preliminary service trials. These demonstrated the raising of black-out thresholds by up to 3g and reduction of the fatigue from high-g manoeuvres.

After some further refinements, the Franks Mk III suit was produced, issued for trial to the Fleet Air Arm, and was successfully used in 1942 by Seafire pilots of 807 Sqn at Oran in French North Africa. Later in the war, on D-day+1, Seafire pilots were still using the g-suits and Mike Crosley, flying the Seafire in combat against FW190s and Me109s notes:

"Thanks to my g-suit I remained conscious in the steep pull-out and regained altitude astern of their ar**-end Charlie after all ….." (Delve, 2007).

The suit was little used by the RAF, partly because of worry that with such g-protection pilots might exceed the structural limitations of the aircraft, and the security limitation that aircrew were forbidden to use this secret system over enemy territory, largely because there was no evidence of g suits in shot-down German aircraft.

Happy landings,

Talisman

And here's the P51D's pilot's seat, and it's adjustable:

It says, "The seat is adjustable vertically." That means that the seat can move up and down; it doesn't say anything about tilting forward and backward.

I think we are forgetting that that this is a sandbox... As far as what few when. Not a historical representation of the aircraft. I asked a question of VEAO if in the Bearcat they were adding anything additional in the way stimulating the G-suit and was told no. Without reading through the other forum, the G-limits are probably an "average" of were the "average" pilot might passout.

It says, "The seat is adjustable vertically." That means that the seat can move up and down; it doesn't say anything about tilting forward and backward.

 

 

 

Your text says, "The suit was little used by the RAF, partly because [...] aircrew were forbidden to use this secret system over enemy territory."

 

If so, then it makes more sense to model no G-suit in the Spitfire.

Yep its only up and down. But still the Fw190 seat doesn't look all that amazing. Its just a regular seat. Nothing fancy. It looks actually like an less comfy P-51 seat.

Maybe the MkIII suit was used on few ocassions, but what about MKII? Also, how is it that K4 and D9 can fight underdog Spit and P-51 and people still want to lower the fighting chances for the allies?:huh:

how is it that K4 and D9 can fight underdog Spit and P-51 and people still want to lower the fighting chances for the allies?

My opinion on WWII fighters in DCS has always been that historically-common, average examples should be chosen. That they haven't always been, was not my choice. Coincidentally, pushing everything toward historically-common & average would involve the P-51 being more powerful than it is now, not less. However, it would also mean the Spitfire wouldn't get the G-suit, because it wasn't historically-common for that aircraft (if the prior quoted text is accurate--I don't know if it is or not, as I am not very knowledgable about the Spitfire).

So, if I had things my way, the P-51 would be more powerful than it is now (by being given historically-common G-suit and historically-common higher WEP rating), while the Me 109 would be less powerful than it is now (by the more historically-common G model being chosen instead of the K). That should solve both problems (relative fighting ability, and historical significance) at once. The Spitfire, too, would be an ~average example of a Spitfire; I don't know what that means for how powerful it would be, but I can't imagine the Spitfire being the underdog in a dogfight against anything other than a Japanese turn-fighter, given the Spitfire's reputation for being a fantastic dogfighter. (In other words, I do not believe anyone need fear that a middle-of-the-road Spitfire will struggle to be competitive without a G-suit.)

In such a hypothetical situation, finer balance could then be achieved by further selecting better or worse examples accordingly (if the "average" Spitfire, for example, turned out to be dominant, then a slightly-below-average Spitfire could be chosen instead, and vice versa), but still each one remaining within the realm of common & average. Not that such a hypothetical situation really matters, as things will never be how you or I want it to be; I'm merely expounding on this to demonstrate that my preference is an accurate & fair representation of all of the fighters involved, rather than skewing the balance in favor of one side or the other.

As I've noted before, Allied "fanboys" accuse me of being anti-Allied/pro-Axis, and Axis fanboys accuse me of being pro-Allied/anti-Axis. I have angry messages in my PM inbox from each, accusing me of being one of the other. To an extremist, I guess, a moderate looks like an extremist of the opposing viewpoint. That I get heat from both sides, indicates to me that my stance isn't too far from the desired objectivity. ; )

(For the record, if you gave me the choice of flying a real-life P-51 or a real-life Me 109, it would be an agonizing decision and a coin-toss might be necessary to decide the matter. I have no great preference for either of the two fighters; they are both amazing, beautiful airplanes, and each was quite a threat to the other during the actual war.)

http://forum.keypublishing.com/attachment.php?attachmentid=66977&stc=1&d=1109148210

Orly? The angle for both Fw190D and P-51D is almost identical.

From reading the extract below, from this link, It would appear to be fair to model the G-suit for the Seafire.

 

Your text says, "The suit was little used by the RAF, partly because [...] aircrew were forbidden to use this secret system over enemy territory."

 

If so, then it makes more sense to model no G-suit in the Spitfire.

Whoops! My apologies; I had badly misread your post. Somehow, I missed that that the text was differentiating between (Royal Navy?) Seafires and RAF Spitfires. (That's what I get for checking the forum before I've had my coffee.)

So, an amendment would be, "If so, then it makes sense to model the G-suit for the Seafire but not for the regular Spitfire."