Author Topic: Hammerhead  (Read 1475 times)

Offline Benny Moore

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Hammerhead
« on: January 29, 2007, 11:01:51 PM »
I've always flown the P-38, so I've never had a problem doing an aerobatic hammerhead.  However, recently I've been expanding into the other two of the Big Three, and haven't been able to perform it nearly as consistently.  Now one of the regulars in my server has suggested that the stall modelling is bogus and that his Me-109 cannot hammerhead.  I immediately began defending the stall modelling, as it's by far the best I've seen in any aerial combat simulator.  However, upon actually trying to hammerhead the 109 I came to the conclusion that he is at least partially right; the Me-109 can't do a hammerhead.  I tried power off, I tried power on; I tried light, I tried heavy; I tried going with the propeller, I tried going against the propeller.  I'm stumped.

Can anyone do a true hammerhead in an Me-109?  If so, can you post a film with instructions?  And if it can't, is it intentional modelling based on the real Me-109's stalling characteristics or is it a bug?

Offline NHawk

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Hammerhead
« Reply #1 on: January 30, 2007, 06:21:12 AM »
Benny if you are able to do a true hammerhead in AH I'd like to see a film of it. I've never been able to do one in any plane in AH.

Even HT has trouble flying the vertical line in AH.

Are you sure you're not doing what amounts to a more vertical wing over?
« Last Edit: January 30, 2007, 06:45:53 AM by NHawk »
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Offline Benny Moore

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Hammerhead
« Reply #2 on: January 30, 2007, 07:35:28 AM »
http://users.adelphia.net/~j.r.engdahl/josh/P-38%20Hammerhead.ahf

It's not perfect, but I do think it counts as a proper hammerhead.  I think I can also occasionally do this in the P-47 and P-51, but nowhere nearly as neatly or consistently.  However, I simply cannot do it in the Me-109.

Offline NHawk

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Hammerhead
« Reply #3 on: January 30, 2007, 08:44:59 AM »
Sorry to say, that's a more vertical wingover with a stall at the top. :)

A hammerhead is straight vertical with rotation on the yaw axis and straight back down. The yaw rotation is done with full rudder and opposite aileron and stopped with opposite rudder.

Trust me it's not you or the coding, without the sensation from the seat of your pants and a good reference point you'll always roll over the top (as you do in the film) resulting in a high wingover or come up short with a true wingover when trying to do a hammerhead in AH.

The only way I can see a true hammerhead being done in AH is 1..pure luck or 2..If HT adds a vertical bubble guage on one side of the plane.
« Last Edit: January 30, 2007, 09:14:00 AM by NHawk »
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Offline Mace2004

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Hammerhead
« Reply #4 on: January 30, 2007, 09:17:35 AM »
I agree that a pure, aerobatic hammerhead is tough to do with the 109 but you can't blame stall as the wing never stalls in this maneuver.  Stall occurs when you reach critical AOA and in a true hammerhead you are looking for zero lift on the wing so have 0 or slightly negative AOA.  

As you decelerate in the vertical you actually have to feed in quite a bit of forward stick to keep from arcing over onto your back and stay pure vertical.  As you start the hammerhead with full rudder (lets say left) the stick needs to go forward and to the right.  Forward to maintain vertical and to the right to counter torque and dihedral affects.  Since you're pivoting the plane around the yaw axis as NHawk describes the right wing is moving faster than the left and will generate a slight amount of lift causing more of a wingover if you don't counter it with right stick.

The ability to do an aerobatic hammerhead depends quite a bit on your rudder power, i.e., it needs to be effective enough to generate enough yaw at slow speeds.  Torque and dihedral are also significant issues.  I have no idea if a real 109 has the ability to do a pure hammerhead.

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Offline HomeBoy

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Hammerhead
« Reply #5 on: January 30, 2007, 09:43:30 AM »
I used to fly RC aerobatic competition and the hammerhead was sort of my signature maneuver.  Obviously there is a bit of difference between an Extra 300 and a 109.  :D   However, here is how I do a hammer in an Extra 300:

From level flight pull straight up into a vertical and go full throttle.  About half way up the vertical line I pull back to idle and let the plane coast the rest of the way up the line using  very slight aileron and elevator inputs to keep things perfectly straight.  Now the tricky part:  just as the plane comes to a complete stop in the vertical (stalls), goose the throttle (full up and back down) and simultaneously kick in full rudder while making very fine corrections with aileron and elevator.  If timed just right, the tail will slide around so that the nose is pointed back down the direction it came while continuing to remain perfectly on the vertical line.  Ease back up on the throttle a bit on the down line just to keep it from wobbling too much.  The tail will give a little "wag" on the down line.  Judges love to see that little wag as proof that your plane actually stalled as the hammerhead is a true stall maneuver opposed to a wingover where there is no stall.

Hope that adds a little to the discussion.

BTW, I've never had any real luck doing this in Aces High in any plane.
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Offline Benny Moore

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Hammerhead
« Reply #6 on: January 30, 2007, 10:30:38 AM »
I'm fairly certain that I didn't roll in that clip.  Watch it from "fixed" view.  I rotate purely on my yaw axis (barring a few degrees of roll, as I said it's not a perfect hammerhead).  I'm still not sure what a wing-over is, as I've heard many conflicting descriptions.  But I do know what a hammerhead is, and I think I got in the P-38.

So, why is it that we can't do hammerheads (not counting the P-38, assuming that it was a hammerhead I did)?  Is it just that hammerheads are very hard to do in reality and since we don't have the feel, it's almost impossible to do them in the game?  Or is it that warbirds were a lot crankier in the hammerhead than modern aircraft?  Or is it a problem with the modelling?

Offline NHawk

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Hammerhead
« Reply #7 on: January 30, 2007, 11:18:43 AM »
The easy way to describe a hammerhead vs a wingover is this.

Take a piece of paper and draw an arrow on it. Hold the arrow pointing up. Rotate the paper so the arrow is pointing down. That's a hammerhead.

Now a basic wingover is like this.. Hold the arrow pointing up, as you turn it slowly to the down position move the paper either left or right of it's original vertical position coming horizontal off of the turn.

I don't know any better way to describe it.
Most of the people you meet in life are like slinkies. Pretty much useless, but still bring a smile to your face when you push them down the stairs.
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Offline HomeBoy

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Hammerhead
« Reply #8 on: January 30, 2007, 12:26:35 PM »
Speaking scrictly from an areobatic competition stand point (a wingover is not a competition maneuver BTW), a wingover is a hammerhead that doesn't stall.  Judges would often write "WO" (wingover) on your scorecard beside the hammerhead maneuver to indicate that you made your down turn too soon and there was no stall at the top.  Hammerheads are pretty much areobatic tricks and (as far as I know) have no usefullness in ACM.

A hammerhead is among a number of aerobatic maneuvers called 3D maneuvers which exploit stalls and prop torque allowing you to perform tricks such as flat spins, tumbles and torque rolls.  I never really got real good at this stuff but I could do basic flat spins, torque rolls and short prop hovers.   Out of all the flight sim games I've played (FS, AH, IL2), I can't do any of this stuff.  I think the physics is just beyond the ability to simulate.  The hammerhead is one in which I would score close to 100 in every competition I ever flew (I can do that one very well) and I can't come even close to doing one in any of these flight games.   I just don't think the simulation can recreate the 3D effects well enough.  

Just my opinion of course.  Maybe some of you guys can do this stuff.  My hat's off to you if so.  I feel pretty confident though that if you can do some of these then you are "gaming the game" rather than doing them as the REALLY are done.  I remember when I first got FS2004.  One of the very first things I did was take Patty Waggstaff's Extra 300 up for some hammerheads.  I was big time disappointed that I was unable to even come close to doing one.  I'm sure there is a "gamming trick" to doing it but I lost interest real quick as I realized that the physics just wasn't there.

I think the appropriate phrase may be "a game's gotta know its limitations."  As for me, I can live with that.

-hb
« Last Edit: January 30, 2007, 12:33:26 PM by HomeBoy »
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Offline Hawco

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Hammerhead
« Reply #9 on: January 30, 2007, 12:39:29 PM »
Forgive my ignorance here, But when would a hammerhead be good in AH? Is it more of a Aerobatic manouver? It looks like you go straight  up till you stall then fall back  down again? A rope manouver perhaps?

Offline Gumbeau

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Hammerhead
« Reply #10 on: January 30, 2007, 12:43:07 PM »
With trails on it is obvious that Benny's clip isnt a hammerhead. If it were there would be no seperation in the up and down trails.

But the larger question is why you want to do a hammerhead?

Offline HomeBoy

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Hammerhead
« Reply #11 on: January 30, 2007, 12:45:44 PM »
Quote
Originally posted by Gumbeau But the larger question is why you want to do a hammerhead? [/B]


Because it's fun?
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Offline Benny Moore

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Hammerhead
« Reply #12 on: January 30, 2007, 04:18:37 PM »
I wanted to do a hammerhead because someone complained that the vertical stall modelling was unrealistic, and I was trying to prove him wrong.  That, and it's fun.

Offline Mace2004

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Hammerhead
« Reply #13 on: January 30, 2007, 07:50:08 PM »
About the only real reason you might use one would be in a very competitive rope where the other guy has just slightly less e so you have to stretch your vertical move as far as possible.  In reality you're just doing a rudder reversal and some roll during the maneuver will pretty much give you the same result and it's easier.  

Regarding the modeling I'm not really sure.  I don't know for a fact that WWII fighters were really capable of a true aerobatic hammerhead but I do know that you don't seem to get the "kick" from the blast of power right at the top so you don't really seem to be able to generate a lot of yaw rate which is what you need.  Regarding the "stall" the hammerhead isn't a stall, it's a ballistic maneuver.  The airplane is too slow for aerodynamic control to have much effect, hence the blast of power to kick the tail around.  The reason it isn't technically a true stall is because when you're going pure vertical you're not getting (nor do you want) any lift from the wing at all so no lift, no AOA, no stall.  

As far as other aerobatic maneuvers in AH, it's also very hard but not impossible to get a true tail slide; however, I've tried numerous times to do a Lomcevak and have never successfully done it.  In another thread I've asked about both the prop wash for rudder reversals and whether or not moments are modeled around all three axis which is what's required, along with control power, for the Lomcevak.

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Offline Oleg

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Hammerhead
« Reply #14 on: January 31, 2007, 01:04:43 AM »
Hammerhead

Never can do it in AH2 as i did in WB time ago.
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