Hurricane

[MK-84]

Are we talking about actual damage sustained from over-speeding an aircraft?  Or the damage model that our game is capable of to discourage such behavior?

[Krusty]

Mk84, it isn't just to "discourage behavior" -- instead it is wrongly implemented and historically inaccurate. We, however, were comparing real world to what AH has modeled. More likely an attempt to create an arbitrary "weakness" to a plane.


By the way, let's just get one thing straight here. I know flutter is an all-encompassing thing. All parts of a plane, building, bridge, or even telephone pole can experience violent flutter.

This topic is specific to the control surfaces themselves. Most combat fighter aircraft have proven they are strong enough to withstand metal-shattering levels of flutter*. Mace saying the flutter ripped off the elevators and ailerons is absurdly. Such an amount of flutter would shatter the entire airframe along with the control surfaces. Yet we have almost EVERY test flight in the history of WW2 aircraft to show us that flutter didn't do such things. Hence his claim that flutter rips control surfaces off of WW2 aircraft in dives is wrong.

*= poor phrasing, but meant to suggest weaker commercial or civilian planes would not withstand it.

P.S. Flutter is most definitely not limited to clotch-covered control surfaces. It has little to do with whether they are metal covered or fabric.

[SkyRock]

Krusty, I'll try and look up where I read that, I've read a ton of material so it may take some time... but I definitely remember reading where the hurri, TA152, C202, and seems like the early yak had aileron failures in dives.... sorry for not having the source on hand...

[Wmaker]

You're trying to imply flutter is lethal, when it is not. Flutter causes a flight surface to flip up and down rapidly. When the surface is fixed in place, these translate into vibrations along the mounting points and the control arms or cables. It makes it harder for a pilot to hold the stick steady, for example. In Leeward's case, the flutter on the trim tab induced vibrations into the control arm, which became detached because of poor maintenance on the point of attachment. Once detached, the trim tab flapped up and down wildly (like a limp flag being whipped back and forth in a massive wind). The trim tab then failed, because it is only held onto the elevator by a handful of screws.

Actually there are plenty of cases where control surfaces have been lost due to flutter and cases where the wings/airframes have come apart due to it.

For example, flutter became a problem during the development of VL Myrsky fighter. On November 19th 1943 MY-3 and test pilot Siltavuori were lost due to brake up of stabilizers and wings in high speed dive due to flutter. During diving tests on 23.6.1944 left elevator half departed from MY-6 due to flutter.

Source: Lentäjän Näkökulma I

You truly aren't understanding how much force is involved when air is moving around the control surface at speeds over 500mph. You need to actually read about the phenomenon before talking about it.

Examples of flutter: http://youtu.be/qpJBvQXQC2M

[Mace2004]

Thanks Ack-Ack, I was aware. His direct equation of flutter effect to ripping control surfaces off of HTCs variant of the Hurricane is so far off as to show he's making a poor joke or doesn't know much about WW2 aircraft. He may be a great F-14 pilot, and I won't dare impugne his service, but from his comments he doesn't know much about WW2 aerodynamics.

I was honestly trying to enlighten him, and not to pick on him (if that was the feeling).

Well, well, aren't we just a bit full of ourselves?    I've tried to be reasonable about this and explain the facts but you're really the proverbial horse who won't drink the water. What makes this really interesting is that you seem to be suffering from the delusion that you're doing the leading. I suggest you take a drink before you faint Mr Ed!

Let me quote the most illuminating comment you've made:

You imply flutter is lethal, which it is not

Maybe I'm just not being clear.  I'm not "implying" a thing, I'm stating flat out that flutter is lethal and a perfectly reasonable failure mode for HTC to emulate in their flight model.  I've also said I have no idea if the speeds this occurs at in AH are correct or if it's an established fact that the Hurricane's elevators came off, I've simply said that it's a fact that parts, including elevators and even wings can come off of any plane due to flutter therefore it's reasonable to model such issues in the game.  You, by the same token, cannot seriously argue that these failures never occured in Hurricanes as, if they did, there would be few pilots actually available to write a report about it.  You can debate all you want about whether a particular surface or another will fail but the simple fact is this exists, it's not "inconsequential" or a "myth" as you claim.  Flight control surfaces, stabilizers, and even wings have come off so what real difference does it make to argue that it's impossible for an elevator to come off, especially where you have no facts to back up that assertion?

But you say flutter can’t do this anyway.  Your one example of a P-40 is missing a key fact that I've explained before (and you seem to just ignore) that the amount of damage done by flutter is directly related to the speed at which it occurs.  This also is the reason that flutter, in a dive at excessive speeds, is extremely damaging.  F=MA and all that.  You have no idea what speed the P-40 was at but it's obvious he was below the speed at which enough energy would be added to the flutter to cause failure.  I’ll bet his return was as slow as possible and scary as all get out but if he dove the airplane in that condition he would, with absolute certainty, eventually reach a speed in which the rudder or tail would have failed.  You also ignore the fact that you're relying on the reports of survivors, what about those that couldn't write one?  I even gave you an example of the loss of a flight control of which I have direct personal knowledge but you're being kinda ignoring that.

Maybe you'll believe Georgia Tech:

The first recorded and documented case of flutter in an aircraft occurred in 1916.  The Handley Page O/400 bomber experienced violent tail oscillations...The incident involved a dynamic twisting of the fuselage to as much as 45 degrees in conjunction with an antisymmetric flapping of the elevators.  Catastrophic failure due to aircraft flutter became a major design concern during the First World War and remain so today."
http://catdir.loc.gov/catdir/samples/cam031/2001052552.pdf

Maybe you'll believe NASA: The pilot in this is Fred Haise who was later the Lunar Lander Pilot on Apollo 13 and did the flutter testing for the Space Shuttle while flying Enterprise.  The test was stopped before the plane lost its horizontal tail but after the flight Haise said "I'm fearless but that scares me."   http://www.youtube.com/watch?feature=player_detailpage&v=pEOmCkZyXzk&list=SPCCF3D4E62537914E

Remember that you said flutter can't rip off elevators and ailerons, that it's "absurd"?  Or that "most combat fighter aircraft have proven they are strong enough to withstand metal-shattering levels of flutter?" How about "flutter is there, but control surfaces are strong enough to survive with it?"  So, at the beginning you said flutter was little more than a vibration (I’d guess Haise would disagree) and you still deny that it's powerful enough to rip off elevators and ailerons, and that fighters (and their control surfaces) are too strong to be affected.  These are nothing more than blanket statements of unsupported opinion masquerading as facts.  Let’s check out an example to see how your "facts" stand up in the real world.  Here's a perfect video example of just how powerful flutter forces can be. http://www.bing.com/videos/search?q=f-117+crash+maryland&view=detail&mid=2BE0018CE1CE944C4D252BE0018CE1CE944C4D25&first=0&FORM=NVPFVR

Maybe, just maybe, you'll consider what I said rather than being simply argumentative.

[Stang]

I'd say that pretty well covered it, Mace.

Here's a link to how flutter affected the X15's tail surface and how far they had to go to overcome the disastrous results of it.

http://youtube.com/watch?v=aZdMTfKeIoQ

[Franz Von Werra]

Most planes have a Vne... Velocity (never exceed)... this is discovered by test pilots before the combat pilots get the planes. Bad things happen when reaching 'never exceed' speed.

Be glad that the whole plane doesnt just shatter and/or including the canopy, so all we have left is the chute.

Guessing that Vne for the pilot would be less than for the plane?

Maybe each plane should show this value on the speedometer - red shaded area? Wish list stuff?
What do the handbooks say about Vne? Might as well note Vcompression while were at it?

[Wmaker]

Pilot's Notes for Hurricane IIa/IIb/IIc/IId/IV give a Vne of 390mph IAS.

[nrshida]

strong enough to withstand metal-shattering levels of flutter*.

Metal-shattering, wowsers. I wish I had a copy of the Marvel Comic Book of Metallurgy.

[B3YT]

In a book called "set guns to fire" a hurricane wing commander and BoB ace says they often went over 450mph in a dive to evade 109's you just had to be careful. One pilot is 6 squadron (my grand fathers  squadron) was credited with a "kill" when he entered a dive with a 109 behind . he got up to 420mph pulled back hard and heard a very loud "crack". the next thing was laughter and cheers from his wingman who told him the 109 that was chasing him folded up trying to follow him  out of the dive . My grand dad spent 12 hours trying to fix that hurricane  . there was a crack running down the width of the wing where it joins the fuselage next to the wing tanks . he flew back with held together pretty much just by the control wires . when he did land the wing was level instead of an upward dihedral.  wooden wings were thought of as stronger by the ground crews as they  had less issues in a dive .