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XyZspineZyX
08-27-2003, 07:07 PM
Hi guys,

Do you know how many 360 degrees turns can a pilot endure at 3G and 5G? In my understanding a well trained pilot can make a single turn at 7G. Can he make more than 4 to 6 turns at 3G considering the fatigue caused by the fact that he weights 3 times more?
Thanks.


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XyZspineZyX
08-27-2003, 07:07 PM
Hi guys,

Do you know how many 360 degrees turns can a pilot endure at 3G and 5G? In my understanding a well trained pilot can make a single turn at 7G. Can he make more than 4 to 6 turns at 3G considering the fatigue caused by the fact that he weights 3 times more?
Thanks.


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XyZspineZyX
08-27-2003, 07:10 PM
Huckebein_FW wrote:
- Hi guys,
-
- Do you know how many 360 degrees turns can a pilot
- endure at 3G and 5G? In my understanding a well
- trained pilot can make a single turn at 7G. Can he
- make more than 4 to 6 turns at 3G considering the
- fatigue caused by the fact that he weights 3 times
- more?
- Thanks.


Depends on the pilot, but if you're used to the high loads, then you'll take it with a smile /i/smilies/16x16_smiley-wink.gif

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XyZspineZyX
08-28-2003, 02:29 AM
Well I do not know how feels 5G but if you do you first acceleration stall in Cessna and start to make this tide turn, first feeling is strange. Everything start to be small and tide, later you used to this but the first time is a very odd sensation.
BTW I wonder if there were any buffering in WW2 fighters which tell you stall is comming. I haven't seen in in Il2, so far, but I haven tried all planes yet after the patch.

XyZspineZyX
08-28-2003, 07:48 AM
The question that you asked cant be answered exactly unless you say what speed the aircraft is travelling at, as far as number of turns. There is a strong correlation between G load tolerance and the time that the load is acting on the pilot, and the rate at which the load is applied.

A typical pilot in good shape with proper G tolerance techniques can generally handle an impulse force of very high Gs, a force applied at a rate of 7G's/Second for about 1 second before blacking out, a force of about 1G/second for 5 seconds, and only .4G/second at 11 seconds. So 7-8 Gs is the practical limit. Extremely prepared aerobatic pilots may be able to pull more, but only for a VERY short time. Some aerobatic pilots will pull up to 12 positive G's for a very short time, and up to -6 G.

And I seriously doubt they are smiling then!

Edit:
If the above didnt make sense, then think of it this way. . most people can only tolerate a sustained G load of 4 G before they lose peripheral vision, and 5 before blackout. (G suits will extend this somewhat)


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Message Edited on 08/27/0311:02PM by TX-EcoDragon

XyZspineZyX
08-28-2003, 08:01 AM
USAF Flight Surgeon's Guide:

http://wwwsam.brooks.af.mil/af/files/fsguide/HTML/Chapter_04.html

Up to 4-5G pretty much indefinitely, once the cardiovascular system has caught up with what is going on. Just find a good spot to rest your head... and that is without a G suit, so crank it up a few if you are wearing one of those.

Even a prolonged moderate ~2Gs will be felt in your neck after a while, trying to move your head around to see other aircraft. That I know first-hand... but I don't think muscle fatigue is what you're going after?

Cheers,
Fred

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XyZspineZyX
08-28-2003, 08:59 AM
MiszaNC wrote:
- I wonder if there were any buffering in WW2
- fighters which tell you stall is comming. I haven't
- seen in in Il2, so far, but I haven tried all planes
- yet after the patch.


Well, there is a lot of buffering before stalling, but you can feel it much better if you have a Force Feedback joystick. This peripheral is almost a must if you want a worth gameplay in Il-2.

- Dux Corvan -

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XyZspineZyX
08-28-2003, 02:25 PM
I have a couple of further quesitons:
How many Gs were capable to pull the real WWII planes we have in FB?
And did something like an anti-G suit existed at that time?

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michapma
08-28-2003, 03:29 PM
I would venture to say that in most WWII aircraft and in most G maneuvers, the pilot represented the G limit. However, for short applications of very high G I am sure the G-limit of the airframe could be reached and the wings might be damaged or torn off.

I remember reading in Shaw that anti-G suits were first developed in the last couple of years of WWII. Advances in G-suits have added a G-tolerance of 1 to 2 Gs on those early designs, though.

Mike

<table width="100%" border="0" cellspacing="0" cellpadding="10"><tr valign="middle" bgcolor="#3e463b"><td height="40" colspan="3" align="center">The ongoing IL-2 User's Guide project (http://people.ee.ethz.ch/~chapman/il2guide/)</a></td></tr><tr bgcolor="#515e2f"><td width="40%">FB engine management:
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XyZspineZyX
08-28-2003, 04:18 PM
It depends on what you are used too. In the RV-4 I fly a steep turn at 60 degree of bank can generate 3 g's easily. You can sit up there and fly in circles till you run out of fuel.

You can withstand quite a bit of G loading if it is just for a second or two. Now if you get in an F-16 where it can sustain 10 g for a prolonged period of time you are in for a beating even with a G-suit. Another problem arose with the F-16 in its ability to load G-so fast that the pilot would black out even with a G-suit. Of course the onboard fly-by-wire can be set to disallow g-loadings over proscribed limits depending on mission parameters.

But yes the better shape you are in and if you are turnin and burnin all day long hey the more you can sustain up to a point of course.

We have friend now retired Navy Test Pilot out of China Lake. He flew an F4-Phantom, an F-86 Sabre and a Sabreliner down there. In fact he had them at his own disposal since he had to be current on all three. The tested his G-suit and found it to have failed. Well it really did not matter since he did not wear it anyway and he went up daily on joyrides turnin and burnin. He had a lot fun! In fact he blew out windows of a small town down in the desert when he went supersonic at tree level doing a buzz job.

Enjoy the G's


Happy hunting and check six!

Tony Ascaso, RN

XyZspineZyX
08-28-2003, 05:04 PM
I felt pretty good at 3G no matter for how long, but 5G is already something else.

Alex "Bloodhound" Voicu

XyZspineZyX
08-28-2003, 05:29 PM
tascaso wrote:
- It depends on what you are used too. In the RV-4 I
- fly a steep turn at 60 degree of bank can generate 3
- g's easily.

How is this possible?

A 60 degree bank, level (no altitude loss) turn will generate a load factor of 2g, and that's all. To generate 3g you'd need a bank angle of roughly 70 degrees.

4g would be about 77 degrees, 5g would be about 80, and strictly by the numbers, 90 degrees requires infinite g (neglecting lift from the fuselage and power).

Still, the point is taken that 4 or 5g should be fine for most people.

How's the RV-4, BTW? I'm hoping to get started on an 8 of my own within the next 12 months, finances permitting. /i/smilies/16x16_smiley-happy.gif

XyZspineZyX
08-28-2003, 05:46 PM
Another interesting thing That I'm pretty sure is not modelled...

In modern planes you have a pressure suit of course to keep all your blood from pooling at your feet - This enables you to take a lot more g's..

The FW190 you sat with your legs straight out in front of you which also enabled you to take more g's.

You should get the blackout effect later in the FW than other planes where you sit in more of a 'chair' like posture..

In my scale FW, its the same - legs straight out in front except to clear the main spar under your knees..

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XyZspineZyX
08-28-2003, 06:47 PM
Thanks effte, excellent link! I'll read it thoroughly.
Can you post a link to the table of contents of that report?


So from your posts I understand that you can actually turn at 3G for longer than 4 to 6 turns, more than 2 minutes, without a G-suit? How much longer?

I read somewhere that a pilot can sustain 5G (no G-suit) for 30-40 sec. Is this true?
Thanks


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XyZspineZyX
08-28-2003, 10:27 PM
Um. . .the average pilot could sustain 4G for a lot longer than 6 turns. You would need a powerful aircraft to sustain that or start with a very high entry speed. (as induced drag increases dramatically with G loading)


Also worth noting here, is that most jet flight teams do not wear G suits becasue the inflation and deflation of the suit makes it harder for them to be as precise as tehy need to be in such tight formation. The real G pullers though are usually the piston engine aerobatic pilots. With short term G loads of up to 12 positive.

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