Official Fulqrum Publishing forum - New structural G-limit feature

Official Fulqrum Publishing forum (http://forum.fulqrumpublishing.com/index.php)

- IL-2 Sturmovik (http://forum.fulqrumpublishing.com/forumdisplay.php?f=98)

- - New structural G-limit feature (http://forum.fulqrumpublishing.com/showthread.php?t=16362)

New structural G-limit feature

Hi,

Read about the new structural G-limit feature, or load factor, and immediately got curious as to how you determined the limits for each aircraft?

Also would it be possible with a G-limit pr. aircraft list?

Finally how does it work exactly, does damage occur when exceeding the std. safe load factor or when closing to design maximum?

Thanks.

As far as I'm aware, the only specific details given about this were in the initial TD announcement of the feature:

Quote:

At present all aircraft in IL2 have a single fixed Structural G limit of +13G. It only really becomes an issue with aircraft with exceptionally light elevators such as the P51. Pull more than +13G and you loose your wings. The real life situation is a little more complicated. Real aircraft are designed with an Ultimate load and In Service design load. Both are for a defined configuration and weight.

The in Service load is the typical G available to the pilot. As long as this the G is not exceeded then no aircraft damage will occur. Exceed the In service G limit then damage of varying degrees may occur .. like bent airframes etc. Exceed the Ultimate load then severe damage will occur typically resulting in structural failure ... like wings coming off etc.Typically a safety factor of 1.5 is used. So an Fighter aeroplane with a design In service G limit of say +8G will have an Ultimate load of +12G. As external stores and or weight is increased above the design weight both G limits reduce accordingly. Reduce weight (by dropping bombs or burning fuel etc) and your G limits increase. Bomber and Transport aircraft have G limits much lower than fighters.
So if you abuse the limits you damage the aircraft. Once damaged then its structural integrity is reduced so the ultimate load reduces as well. In other words keep bending the airframe and you will eventually weaken it to the point that very little extra G is required to induce structural failure. A bent airframe wont perform as well either.

The DT team have now simulated this for the first time in IL2. Each aircraft has been given a unique Structural G profile for Ultimate load, In service limit, and dynamic Weight based limits . In addition this is dynamically modified with its own G induced damage profile. The basic Design Ultimate load configuration and weight has been defined as Default load + 100% Fuel. The actual Ultimate design load has been based on Historical values where they are known and guesstimation where they are not known. In broad brush terms for fighters have an Ultimate design load of +12G with an In service limit of +8G. Lets abbreviate this to 8G/12G

How does this work in game ? You take your stock standard Fighter MK 1 with Default armament +100% Fuel your limits are +8G/+12G. You add 2 x 500lbs bombs. your limits now reduce to 5G/8G. So prior to the target you need to be a little more careful with your aeroplane. Lets say pre target you pull + 6G, you have exceeded the In service limit, you will hear a damage sound cue and suffer a slight aerodynamic penalty. In addition your G limits have now reduced to say 4G/6G. (Bust these again and further aerodynamic penalties and further reductions will apply). You progress to the target and release your bombs. Since the weight is reduced your limits will increase but since you already bent the airframe you wont get back your original limits. You might then get say +6G/+9G. As you can see if you keep abusing the limits you will end with a very weakened airframe.

In the case of heavy bombers G limits will prevent any real aerobatic manoeuvers. You will still be able to evade quite well but you wont be able to BFM with aeroplanes like the A20 anymore. Bombers will be just that: Bombers. G limits will be applicable to AI planes as well and they will fly in a more realistic way too.

Is G displayed? Unless the aircraft in game is equipped with a G meter then no. So you will need to re think how you fly. Random snatches particularly at high speeds are going to hurt .... just as they do in real life. You will need to be aware of Corner speeds because any time you are faster than Corner speed you run the risk of an Over G event. (We are yet to finalise the display side of things)

http://forum.1cpublishing.eu/showthr...ile#post136666

I suspect any further info about this will have to wait until the patch is released - hopefully not too long now.

This is probably my favorite feature of 4.10, I think it will change some of the extreme unrealistic maneuvers that occur both online and offline.

bad news for the spit crowd - or say some of them...

Quote:

Originally Posted by swiss (Post 181180)

bad news for the spit crowd - or say some of them...

I reckon it'll be worse for the P-51/190 crowd myself - high speed manoeuvrability more easily allows excessive G's than the spit's elevator.

Well if they use the real life limit load factors then it would be pretty bad for Spitfire pilots as the limit load factor for the Spitfire was some 5.33 G's compared to the std. German 8 G's and US 7.33 G's.

But then again, most pilots back then blacked out at around 4 G, so anything above 5 G is gonna entail flying in the blind anyway :P

Quote:

Originally Posted by AndyJWest (Post 181160)

As far as I'm aware, the only specific details given about this were in the initial TD announcement of the feature:

http://forum.1cpublishing.eu/showthr...ile#post136666

I suspect any further info about this will have to wait until the patch is released - hopefully not too long now.

I wasn't aware of this being a feature until now, I tend to simply wait for patches to arrive.
This is great news though. It's always been a gripe of mine, when He111's and B-17's perform impossible feats of aerobatics.
It might also reduce the prevalence of BandZ-ers online.
BandZ is so boring. Even when I do it myself!:grin:

Quote:

Originally Posted by Bellator (Post 181232)

5.33 g's for a spitfire max g-limit? Where does this information come from? For example the F8F Bearcat was restricted to 7.5 g's after failures of its wingtip ejection system, I highly doubt that a lighter and smaller fighter which saw exponentially more combat than the Bearcat, and with no history of chronic failures would have a limit of 5.33 g's. The g-limit would vary between aircraft, not between countries.

I'd be wary of comparing G-limits between aircraft without being sure that they were actually measured the same way. An operational G limit would presumably be based on the expected failure point, minus a safety factor. But would all safety factors be the same? Unless you know this, you can't make comparisons.

Quote:

Originally Posted by Tempest123 (Post 181273)

Now according to what I've read British aerospace std. requirement was a limit load factor of 5.33 G for their fighter aircraft, and the Spitfire was designed & built according to this. The German aerospace std. limit load factor was by comparison 8 G's and the US std. was 7.33 G's

The advantage of the lower British std. was the ability to build their aircraft somewhat lighter.

The ultimate design load factor is usually found by multiplying the design limit load factor by 1.5, at which point you arrive at the designs breaking point. So the Spitfire should be able to take 7.99 G's before breaking up, whilst aircraft such as the Bf-109, P-51 & Fw190 could take between 11 to 12 G's before breaking up.