Structural Failure of Ordnance Attach Points During Loading or Speed

[Guppy35]

I have read of a Spitfire Mk IX's 500lb bomb failing to detach and the Spitfire's wings failing on the high G pull out.  The shackle didn't fail, the wing spar failed.

And boom, we got the E wing with two hard points and strengthened.

The key though was it failed because of the stress on the wing because the bomb didn't come off and the pilot was pulling out.  Can't imagine HTC is going to take the time to model in random bomb hang ups.

I suppose I could post the story of the 370th FG P38J pilot who got into the turn fight with the 109 on the deck and out turned him.  He RTB'd to find that his 500 pounders hadn't come off when he tried to jettison them and had fought the 109 and won despite that extra weight and stress on the wings

[Karnak]

Wasn't quite my point, Dan. 

I was mainly pointing out that the shackles were designed to very high tolerances.


I actually think Spit wings come off too easily in AH as I have never heard of a Spit shedding its wings except a) before the elevators had been given extra resistance to prevent massive G spikes, b) A 500lb bomb got hungup and stayed on for a high G pullout, and c) Spitfire Mk XIVs that were incorrectly reassembled in India.

[AquaShrimp]

In RL, a P-47 on a divebombing sortie had a 500lb bomb hang up on the wing during its attack dive.  The pilot pulled out, but it bent the wing and he had to RTB.

[MiloMorai]

What angle of dive was used? For example the Spit could be dived up to a 60* angle.

[Stoney]

I couldn't remember where I saw this before, but I went back and re-read the P-47N POH.  This is what I'm talking about:

[Yeager]

all good and well guys but when the simulation interferes with the game you are going to find much resistence from HTC.  They are most interested in the middle ground.  Realistic stress physics under maximum loading are performance characteristics outside the scope of good gameplay.  Imagine all the wings popping off of dive bombing lancasters and you will get my drift 

[Cthulhu]

My assumption as always been that ordnance hardpoints are always attached to the aircraft's spar, other than bomb bays on bombers. Anything else seemed untenable.

You're partially correct Karnak. It's really more critical that the ordinance rack attach to a rib (if wing-mounted) or to a longeron (if fuselage-mounted). This will allow you to shear the fore & aft loads into the skins. Typically the rack will also span between front and rear spars in order to "beam" the vertical loads and ordinance pitching moments to the main spars.

A rolling-pullout is typically the critical load case for wing-mounted stores. The combination of vertical forces, pitching moment, and side-loads on the store can produce some viscious loads on the attachment lugs and rack structure. Flight restrictions (limit g's) will be dictated by whatever part has the lowest margin of safety.

[Stoney]

all good and well guys but when the simulation interferes with the game you are going to find much resistence from HTC.  They are most interested in the middle ground.  Realistic stress physics under maximum loading are performance characteristics outside the scope of good gameplay.  Imagine all the wings popping off of dive bombing lancasters and you will get my drift 

First I want to find out about accuracy, then we'll deal with gameplay issues.